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Abstract

The paper represents the “state of the art” on sustainability in construction materials. In Part 1 of the paper, issues related to production, microstructures, chemical nature, engineering properties, and durability of mixtures based on binders alternative to Portland cement were presented. This second part of the paper concerns the use of traditional and innovative Portland-free lime-based mortars in the conservation of cultural heritage, and the recycling and management of wastes to reduce consumption of natural resources in the production of construction materials. The latter is one of the main concerns in terms of sustainability since nowadays more than 75% of wastes are disposed of in landfills.

Keywords

Sustainability waste management traditional binders Portland-free binders construction materials

Introduction

In Part 1 of this paper, issues related to the production, microstructures, chemical nature, engineering properties, and durability of mixtures based on binders that are an alternative to Portland cement were presented. This second part of the paper concerns the use of traditional and innovative Portland-free lime-based mortars in the conservation of cultural heritage and recycling, and the management of wastes to reduce consumption of natural resources in the production of construction materials. The latter is one of the main concerns in terms of sustainability since nowadays more than 75% of wastes are disposed of in landfills.

Traditional and innovative Portland-free lime-based mortar for conservation of historical heritage

Traditional historic mortars

The addition of natural or artificial pozzolans to lime mortars was practiced since the dawn of civilization. Volcanic eruptions occurred worldwide, and provided ancient populations with natural pozzolanic materials.¹ In the absence of volcanic materials, man learned to use crushed bricks or pottery fragments (cocciopesto when mixed with lime). Earlier use of pozzolans has been proven for Galilean archaeological sites dating back to the Neolithic period.² Further evidence has been found in Crete and Greece.^2–5 Nevertheless, it is only in Ancient Rome that pozzolanic materials have undergone systematic exploitation. It is probably during the century II BC that the Romans discovered the hydraulic properties of the volcanic ash in the area near Puteoli.⁶ Hence, the name pulvis puteolanus was given to the material, from which the modern term pozzolan is derived. Natural aggregate was used as a pozzolanic agent during the Roman Empire.^7–12 The number of ancient buildings surviving time and natural injury testifies well to the extraordinary properties of such Roman mortars.¹³ Since ancient times, knowledge and expertise have been summarized by various authors. Vitruvius points out the ability of harena fossicia^14,15 to impart solidity to structures even in water.^16,17 Pliny the Elder (Naturalis Historia) confirms the extraordinary property of pozzolanic materials in consolidating marine structures.¹⁸

Natural pozzolans were also a main component of opus caementicium, regarded as the precursor of modern concrete.^7,10,19–24 The opus caementicium was used both to fill the void between outer brick or stone wall edges and for hydraulic structures.^{7,19,21,25–27} During the Imperial Age, it became the construction material for most public works.^28–32

Starting from E. B. van Deman’s³³ pioneering work published in 1912, ancient Roman mortars have been attracting increasing interest from the scientific community. Despite this, the complex physical and chemical transformations involved in mortars’ hardening have not yet been fully understood. Significant progress, based on microscopic analysis, has recently been made.^34–40 Specifically, studies demonstrate that the monuments built in Rome throughout the first four centuries AD²⁹ contain Pozzolane Rosse, scoriae erupted by the Alban Hills volcano during the mid-Pleistocene pyroclastic flow.³⁰ Studies carried out on mortars manufactured using the same materials as in the Trajan Markets in Rome have shown³⁴ a crystalline phase, strätlingite, growing at interfacial regions as a consequence of the pozzolanic reaction, thus providing significant mechanical improvement.³⁴ The capability of strätlingite for the distribution of force at interfaces positively influences the mechanical properties of mortar, contributing to blocking the propagation of cracks and microfractures.^34,41 The observed behavior opens up new perspectives not only for a deeper understanding of the relationship between structure and properties in ancient Roman mortars, but also for designing new materials solutions for the restoration and formulation of novel Portland-free sustainable mortars with superior performance in terms of durability and toughness.⁴²

Nanolime in conservation of cultural heritage

European cultural heritage (ECH) is of paramount importance. For this reason, ECH has to be protected following the main “Restoration Principles” outlined in international charts (compatibility, recognition, and little invasive). Materials’ deterioration can be prevented or slowed down by conservative repairs, consisting of restoration and preventive treatments.⁴³ So far, conservation science has focused on polymer-based conservation materials. Organic protectives are, however, generally physically/chemically incompatible with an inorganic substrate.⁴⁴ For this reason, nowadays, the application of inorganic nanomaterials such as calcium hydroxide nanoparticles in hydro-alcoholic dispersion (nanolime) has been successfully introduced in CH for the consolidation of calcareous substrates, in order to reach a compromise between compatibility and efficacy of the intervention.⁴⁵ Actually, nanolime presents the ability to penetrate deep into damaged zones, high reactivity, and fast reactions in the carbonation process.

The procedure adopted to prepare nanolime particles mainly consists of chemical methods, carried out at high temperature and/or high pressure, in aqueous, alcoholic, or organic solvents.^45–49 An recent innovative single-step process, based on an anion-exchange process, to produce nanolime in water at room temperature, has been patented.⁵⁰ The nanolime, dispersed in ethanol, iso-propanol, or water–alcohol mixtures, is composed of pure, crystalline, and thin hexagonal lamellas (Figure 1). Recent studies reveal that the lamellas can be composed of nanoparticles <10 nm in length and 6 nm in thickness.^51,52 Nanolime dispersions are successfully employed on wall paintings, stuccoes, and frescoes, and in the refurbishment of architectonic surfaces.^53–62 In particular, both in wall paintings and in frescoes, the nanolime guarantees a re-adhesion of detached paint layers on the wall substrate.^45,53,54 Promising results are also obtained on stones and mortars, in terms of superficial consolidation as well as reduction of water absorbed by capillarity (up to 70%).^56–62 Nanolime is able to penetrate up to some millimeters from the stone surface, filling the pores without occluding them. Moreover, when applied in diluted dispersions (<5 g/l), nanolime does not produce any relevant chromatic alteration on the stone surface.

Figure 1.

Transmission electron microscopy image of commercial nanolime.

From the results obtained in the different cases, nanolime can represent a promising material for the restoration and preservation of historic works of art, perfectly combining consolidation efficacy with its physico-chemical compatibility with the original historic lime-based material.

Waste management and recycling

Recycled glass

According to the United Nations, glass waste represents about 7% of the total solid waste available. Moreover, glass waste occupies extensive volumes of landfill due to its non-biodegradable nature.^63,64 In addition, the glass industry uses a large amount of natural resources and energy, and it produces high CO₂ emissions. Theoretically, glass can be recycled many times. Mixing different colored glass waste, however, makes the recycling process unfeasible and highly expensive. Thus, the concrete industry can represent a possible solution for an environmentally friendly management of glass waste. Furthermore, the use of glass waste in construction appears among the most sustainable options, since its use could reduce the environmental costs of concrete production.

Firstly, subject to its chemical composition, glass waste should be suitable as a raw material for cement production.⁶⁵ Moreover, being amorphous⁶⁶ and containing large quantities of silicon and calcium, glass is, in theory, pozzolanic if finely ground.^66–71 Many studies^72–75 have confirmed that ground-glass powder exhibits a good pozzolanic reactivity.^72,73 An increase of finely ground-glass content, however, reduces the strength of concrete during the early stages due to a slower pozzolanic reaction compared to cement hydration and a lower cement content.^75,76 Thus, different studies have investigated the optimum percentage of glass powder (5–30%) to replace cement, as well as the optimum particle size (0.1–100 μm). Based on the studies by Shi et al.⁷² and Shao et al.,⁷³ concrete with glass particles passing a 38 µm sieve replacing 30% of the cement exhibited a higher strength than a mixture with fly ash. Mechanical properties are more related to the physical characteristics of glass than to differences in terms of color or chemical composition.⁷⁷ Glass powder can contribute, after proper curing, to a beneficial refinement of the pores,^66,76 and delays the penetration of ionic species.^78–80 The only concern regarding the use of glass powder in cementitious materials is the potential alkali–silica reaction (ASR). Most of the expansion tests that have been carried out in studies^72–79 have shown that ASR expansion decreased with an increase in the percentage of glass powder due to its pozzolanic behavior.

Glass waste⁸¹ is of interest for replacing natural aggregates in concrete. Due to its low absorption capacity, recycled glass aggregate is able to improve freeze–thaw resistance, drying shrinkage, and abrasion.⁸² Topçu and Canbaz,⁸² Idir et al.,⁸³ Corinaldesi et al.,⁸⁴ Jin et al.,⁸⁵ Poutos et al.⁸⁶ and Mladenovič et al.⁸⁷ found that a particle size less than 0.9–1 mm did not induce any harmful effects of ASR with 20% partial replacement of glass aggregate; with a lower particle size a higher percentage could be used safely.⁷⁶ To avoid an ASR reaction in concrete with glass aggregates, is necessary to reduce the size of glass particles and the glass content, and use porous lightweight aggregate^87–92 or supplementary cementitious materials, including finely ground glass.⁸³

Several authors^74,93 studied the combined use of waste glass as a partial replacement for cement and aggregate in the same mixture. Shayan and Xu⁷⁴ demonstrated that after increasing the amount of glass powder (up to 30%) no ASR effects were evident in a mixture with 50% replacement of natural aggregate with waste glass. Recently, processes for the production of expanded glass particles have been developed, and the use of this lightweight aggregate for concrete has been proposed by several authors.^88–92 Carsana and Bertolini.⁸⁸ demonstrated that the combination of expanded glass and silica fume led to a structural lightweight concrete showing a high resistance to the penetration of aggressive agents. Based on the results obtained by Ducman et al.,⁸⁹ in a recent study Bertolini et al.,⁹⁴ have also verified the possibility of manufacturing lightweight mortars with expanded glass aggregates and glass powder replacing 30% of the cement. Preliminary results confirmed the beneficial effects of glass waste in terms of decreasing ASR expansion with respect to standard mortars (Figure 2).

Figure 2.

Expansion in time of mortar specimens with different combination of expanded glass (EG), ordinary sand (OS), glass powder (GP), and ordinary cement (CE).

Aggregates from automotive shredder residues

Every year in the world more than 50 Mt of end-of-life vehicles (ELV) are produced;⁹⁵ as a consequence yielding about 9 Mt of wastes. According to European Directive (2000/53/EC) more than 95% (by mass) of ELV produced after 1979 shall be reused and recovered and more than 85% must be recycled. Nowadays, about 80–95% of ELV are subjected to the disassembling of glasses, transmission components, tires, seats, and liquids drainage. At the shredding plant, an heterogeneous mix – “automotive shredder residue” (ASHR) – is produced,⁹⁶ made up of 75% fine combustible materials with a calorific value >13 MJ/kg.⁹⁷ (Table 1) This waste is highly contaminated with heavy metals,^98,99 however, and it often contains mineral oils and fluids.^100–105 In Europe, ASHR is classified as hazardous waste (Decision 2000-532-EC).

Table 1.

Composition of automotive shredder residue (ASHR).

Component		% (wt)	PPM
Polypropylene (PP)		25
Polyethylene (PE)		5
Polyvinyl chloride (PVC)		10
Acrylonitrile butadiene styrene (ABS)		8
Polyurethane (PU)		8
Polyamide (PA)		6
Rubbers		9
Cables/wires		2
Metals		2
Glass		24
Other		1
Element
	C
	H
	Cl
	N
	S
Heavy metal
	Cd		69
	Cr		826
	Cu		4800
	Pb		2740
	Zn		6900

Regarding the inorganic fraction, excellent results have been obtained transforming the finest particles of ASHR (<4 mm) into aggregates after chemical treatment with calcium sulfoaluminate or Portland cement.^106–108 Rossetti^106,107 pointed out an efficient process for aggregate production from ASHR, consisting of a preliminary separation step, where a fraction containing mainly inert and nonmetallic materials was sieved to obtain the required grading, followed by the mixing of this fraction with binding materials and a superplasticizer agent, to produce granules of up to 2000 kg/m³ specific weight. These aggregates were employed to manufacture concrete with a 28-day compressive strength in the range 25–32 MPa^106,107,109 and noticeable freeze–thaw resistance.¹⁰⁹

Recycled aggregates in concrete

Concrete is one of the most widely used construction material in the world. In most cases, concrete elements are demolished at the end of their life, generating construction and demolition waste (CDW). Pure concrete waste can be obtained if all non-mineral dry building materials (plasterboards, wood, metals, plastics, glass) are removed before the demolition. All these extra materials can be recycled to produce eco-friendly plaster and mortars using wood chips,¹¹⁰ waste glass,^84,111 waste plastics particles,^112,113 and bricks.¹¹⁴

Concerning structural concrete, several papers showed the suitability of reusing up to 30% coarse recycled aggregate particles for concrete strength classes up to 40 MPa.^115–120 Moreover, a correlation between the elastic modulus and compressive strength of recycled-aggregate concrete (RAC) was found by Corinaldesi,¹¹⁶ showing that 15% lower elastic modulus is achieved by using 30% recycled aggregates, while tensile strength is reduced by 10% if the same concrete strength class is achieved by replacing 30% virgin aggregates with recycled concrete particles.^{115–119,120}

In terms of drying shrinkage, lower strains are detected, especially for earlier curing times.^115,116,121 Concerning time-dependent characteristics, creep behavior is more influenced by the presence of recycled aggregates than shrinkage.^118,123

Even if 100% replacement of virgin aggregate is carried out using particles coming from the treatment of CDW, structural concrete can be prepared due to the positive effect on compressive strength achieved by adding fly ash/silica fume and an acrylic-based superplasticizer.¹¹⁵ Moreover, if fly ash is added to RAC, the volume of macro pores is reduced, causing benefits in terms of mechanical performance such as compressive, tensile, and bond strengths.^115,119 In addition, fly ash proved to be very effective in reducing carbonation and chloride ion penetration depths in concrete, even in RAC.¹¹⁵

Finally, on the basis of the results obtained through cyclic loading tests of beam–column joints, those made of RAC showed adequate structural behavior.^124,125 Pprevious encouraging results were obtained by using only coarse recycled aggregate, while many authors found that with RAC the fine fraction is particularly detrimental to both the mechanical performance and durability of concrete. For these reasons a more recent approach is to recycle for concrete production only the coarse recycled fraction. In several works^{114,126–131} the possibility of reusing the fine fraction waste as aggregate for bedding mortars was evaluated.^127,128 Mortars containing recycled fine aggregates develop lower mechanical strength with respect to the reference mixture, particularly when recycled bricks are used. Nevertheless, the bond strength^128–131 at the interface between the mortar and the brick turns out to be higher for mortars prepared with recycled aggregates.

A further opportunity can be the reuse of the very fine fraction (Figure 3) coming from the recycling of CDW as a filler for concrete, especially self-compacting concrete (SCC) mixtures.^132–134 In particular, the rubble powder proved to be more promising with respect to limestone powder and fly ash as a mineral addition for SCC. In conclusion, an optimization of the self-compacting concrete mixture seems to be achievable by the simultaneous use of rubble powder and coarse recycled aggregate.

Figure 3.

Scanning electron microscopy (SEM) image of construction and demolition waste powder at a magnification of about ×800.

Artificial aggregates in concrete

Industrial solid wastes (ISW) represent a widespread threat around the world due to the effects of pollution to human health and the environment. The specific treatment of ISW plays an important role in maximizing the efficiency of recycling processes.^135,136 Among the different techniques, cold-bonding pelletization is often proposed in low-cost building materials production.⁹⁵ In particular, one of the most interesting solutions for waste recovery is the manufacture of recycled artificial aggregates.^{137–143,144} The cement-based cold-bonding pelletization process has recently gained attention.^{107–109,144–148} The stabilization/solidification process uses a rotary plate pelletization pilot-scale apparatus with binding mixes. A double-step pelletization is performed in order to obtain a final product with improved properties.¹⁴⁹ Such a process has been employed incorporating the waste content in the binding matrix from a minimum of 50% (wt.%) up to a maximum of 70%.

After this step, a second one is carried out with pure binder to encapsulate the aggregates (Figure 4) coming from the one step within an outer shell. This further step has proved to be very effective to improve the technological and leaching properties.

Figure 4.

Artificial aggregate obtained by double-step pelletization.

Such an approach has economic and environmental advantages due to the reduced energy requirement (the process carried out at room temperature) with respect to the industrial alternatives such as sintering,^150,151 which is an energy-intensive process. More recently, alternative cement-free binding matrices with reduced embedded CO₂ have been proposed for stabilization/solidification^152,153 such as geopolymer- and alkali-activated materials. These systems have gained an increasing interest from researchers thanks to promising results in terms of their mechanical, physical, and durability properties, and the possibility of synthesis starting from natural/industrial wastes^130,154 for a wide range of applications.^155–159 A further reason for interest in cold-bonding pelletization is a significant reduction of quarrying activities.^160–165

Colangelo et al.¹⁶⁶ and Shi et al.¹⁶⁷ used municipal solid waste incinerator (MSWI) fly ash as a raw material with cement, lime, and coal fly as binders. According to Colangelo et al.¹⁶⁶ and Shi et al.,¹⁶⁷ a pre-washing treatment is been carried out to reduce the chloride and sulfate content in MSWI fly ash since the cementitious matrix has a reduced capability for immobilizing chlorides and other soluble salts. The MSWI fly ash examined has been submitted to a two-step washing pre-treatment with a liquid/solid ratio equal to 2:1¹⁶⁶ in order to reduce the soluble salts content and the production of liquid waste. To obtain the granules the MSWI fly ash samples, after washing pre-treatments, are introduced in a pilot-scale granulator apparatus having a rotating and tilting plate with a diameter of 80 cm. The granules are cured in a climatic chamber for 12 h at 50° C and a relative humidity of 95%. This phase gives the granules the necessary hardening for the handling phase, so it is very effective. The granules are then cured for 14 days at room temperature and humidity. The aggregates produced satisfied all of the tests used in the concrete industry.

Recycled tires in concrete production

The increasing number of vehicles on the roads generates about 1.4 billion end-of-life tires (ELT) worldwide every year. The inadequate disposal of tires may in some cases be a potential threat to human health (fire risk, haven for rodents or other pests) and a cause of environmental risks. The limited space available and their potential for reuse has led many countries to impose a ban on the practice of landfilling. The estimated EU annual cost for the management of ELTs is €600 million.^168,169

The tire is a complex and high-technology product representing a century of innovation, which is still on-going. Tires are made up of: (i) an elastomeric compound; (ii) fabric; and (iii) steel. The fabric and steel form the structural skeleton of the tire with the elastomer forming the “flesh” of the tire in the tread, side wall, apexes, liner, and shoulder wedge. The elastomer is vulcanized and combined to chemicals and reinforcing fillers (e.g. carbon black) to further increase hardness.¹⁷⁰

Tire rubber is resistant to mould, heat, humidity, bacterial development, ultraviolet rays, some oils, and chemicals. Moreover, these materials are not toxic for humans and are very elastic. Many of these characteristics, however, which are advantageous qualities during on-road life, are disadvantageous in post-consumer life and become a problem during the transformation phase.

Recovery includes different options: i) “energy recovery,” where ELTs, having a calorific value equivalent to that of good-quality coal, are used as an alternative to fossil fuels; ii) “chemical processing,” such as pyrolysis, thermolysis, and gasification; and iii) “mass recovery.” The latter, when not applied in the form of whole tires (such as for crash barriers) consists of a “granulate recovery,” which involves tire shredding and chipping, by which tires are cut into small pieces of different sizes (shreds: 25–460 mm; chips: 13–76 mm; crumb rubber: 0.1–5 mm).¹⁶⁸ After the removal of the steel and fabric, the recycled tire rubber (RTR) can be used for a variety of civil engineering projects such as soft flooring for playgrounds and sports stadiums, modifiers in asphalt paving mixtures, or additive/aggregate to Portland cement concrete. Among these, the addition (as crumb rubber) to asphalt mixtures is highly diffused due to the good chemical interaction, even leading to a partial dissolution.¹⁷¹ The recovery of RTR as an aggregate in cement concrete has been discouraged so far by the unfavorable interactions with the matrix and the loss of compression strength. These composites present many advantages and there is much for future research to address, however, as discussed below.

RTR used in cement concrete ranges from crumb rubber powders to rubber chips, and is added to the cement paste by partial (or eventually total) replacement of the coarse or fine aggregates.¹⁷¹ The cement paste is mainly characterized by hydrated metal/semi-metal oxides, which explains the hydrophilic nature (high surface energy). Rubber, instead, is made of organic polymers, which is characterized by a low surface energy, and therefore a hydrophobic character. The hydrophilic–hydrophobic interaction is very unfavorable, resulting in a poor adhesion between the rubber particles and the cement matrix. Figure 5(a) shows scanning electron microscopy (SEM) images of a typical sand-based cement mortar and of a mortar with RTR added (Figure 5(b)): while a perfect adhesion can be appreciated between the sand grains and the cement paste, a significant separation exists between the paste and the rubbery sites.¹⁷² For this reason, various rubber chemical treatments have recently been tested with the purpose of improving adhesion. Treatments with NaOH,^173–175 HNO₃ and cellulosic derivatives,¹⁷⁶ and silane coupling agents¹⁷⁷ have been reported.

Figure 5.

Cement matrices with: (a) sand grains; and (b) rubber particles.

The significant loss of strength (reduction of 45% upon addition of 15% RTR^178,179) is mainly due to the fact that rubber sites are significantly softer than their surrounding media, acting like “holes” inside the concrete. This critical property has so far limited the use of cement concrete with RTR added to non-structural applications such as exterior wall materials, pedestrian blocks, lightweight aggregate in flowable fill for cement concrete, highway sound walls, residential drive ways, and garage floors.¹⁷¹

An enhancement of toughness and the ability to absorb impact energy has been observed with respect to conventional cement concrete (explained and modeled elsewhere), in addition to an increased flexural strength.^171,179

The lightweight character of the rubberized concrete (due to the low specific weight of rubber), should be considered an advantage for its use as a construction material since structural efficiency is currently more important than the absolute level of strength. Specifically, a decreased density for the same strength reduces the dead load, foundation size, and construction costs. Furthermore, the low density enhances sound and thermal insulation, further properties that are relevant to construction applications.¹¹²

The hydrophobic character of the rubber particles, although responsible for difficult adhesion with the cement paste, has recently been proved (Figure 6) to strongly inhibit the absorption of water in rubberized mortars, which is instantaneous in normal (i.e., sand containing) mortars.¹⁷² This fact, which means higher freeze and thaw resistance, represents a further important feature for future developments.

Figure 6.

Water drops (a) absorbed in a normal mortar; and (b) standing on a recycled tire rubber mortar.

Recycled polymers in cementitious mixtures

Plastics products are used in almost every field, particularly in packaging, building and construction, automotives and electronics. The massive use of polymer products, however, involves several environmental issues related to plastics waste management and the possibility of reusing them. In recent decades, several studies investigated the use of plastics waste in the field of construction.¹⁸⁰ The use of recycled polymers in cementitious mixtures can be summarised in three different applications: i) polymeric fibers; ii) plastics aggregates; and iii) polymer-modified concrete.¹⁸¹

The use of polymeric fibers in cementitious materials is able to overcome their brittle nature and cracking resistance. The properties of fiber-reinforced cementitious composites (FRCC) depend on several fiber parameters such as: the amount of fiber (volume fraction); geometry (aspect ratio, surface texture, etc.); and mechanical properties (depending on their nature). Moreover, the fibers’ durability in the alkaline environment and fiber/matrix bond also play an important role in the fiber-reinforced composite’s behavior. A large number of studies have focused their attention on the use of fibers derived from recycled polyethylene terephthalate (PET), polyvinyl chloride (PVC), nylon, and polyolefin.^181–191 PET fibers present some durability issues in an alkaline environment^182,187 while the other common polymeric fibers (polypropylene (PP), polyethylene (PE), PVC, etc.) are not chemically degraded in such an environment. Considering the compressive strength of FRCC, some authors reported a slight increase^183,189 while in other cases a decrease^184,186 of this property in comparison to unreinforced cementitious composites. The different results are explained by considering the ability of fibers to, in the former cases, exert a confinement action; or, in the latter cases, the weak bond between fibers and the cementitious matrix. On the other hand, the splitting tensile strength and flexural strength of FRCC increases with the fibers’ volume fraction.^{183,184,186,192} FRCC properties are greatly affected by the addition of fiber, depending on the fibers’ volume fraction and geometry. Generally, an increase in the quantity of fiber gives a decrease in workability.^184,189,192 Several studies focused their attention on the investigation of the interfacial transition zone (ITZ) between fibers and the cementitious matrix because synthetic fibers, have, in general, no chemical interactions with the cementitious matrix. Moreover, due to the smooth surface of traditional polymeric fibers, very poor adhesion exists between the reinforcing phase and the matrix. To improve adhesion and/or interactions between fibers and the cementitious matrix, two main approaches have been investigated: fiber mechanical deformation or surface chemical treatments, and ITZ densification. In the first case the aim is to increase surface contact area using crimped, twisted, fibrillated, or embossed fibers.^185,186 Mechanical deformation of fiber increases friction during pull-out, delaying fiber/matrix debonding under load. ITZ densification provides a more uniform and continuous interphase between the two components while fibers chemical treatments, like graft copolymerization of acrylic acid, alkaline hydrolysis, nano-silica deposition, and oxygen plasma allow chemical interactions between the fiber surface and cement paste.^193–194 Finally, many authors investigated the use of recycled polymeric fibers to contrast shrinkage cracking phenomena in cementitious materials. Crack number and area decrease with an increase of the fiber volume fraction, also depending on the fibers’ geometry and morphology.^185,186,188

Another viable strategy for polymeric waste recycling is their use as aggregates in mortars or concrete. For this purpose, aggregates of different sizes (coarse and fine), geometry (pellets, flakes, etc.) and polymeric nature (PET, PP, polystyrene (PS), high-density polyethylene (HDPE), PVC, etc.) have been investigated.^{112,113,160,196–204} On one side, using plastics aggregates it is possible to obtain lightweight materials with a lower thermal conductivity, compared to traditional cementitious materials.^{112,113,196–198,203,205} Moreover, several authors have reported an improvement of acoustic isolation and impact resistance.^181,196,197 The addition of plastics aggregates also leads to a compressive strength decrease.^{112,113,160,196–203} In this case, however, the aggregate/matrix affinity plays a fundamental role and different strategies have been proposed in the literature: the improvement of aggregates’ surface roughness, the densification of the ITZ, or using expanded aggregates.^{112,160,197,199,200} In this particular case, aggregates’ open porosity is able to offer interlocking positions for the cementitious paste, thus enhancing the adhesion and the homogeneity of the ITZ.^112,160 Several studies, however, report a reduction of workability of such composites, resulting in poor compaction and thus an increase in porosity.^160,195 Durability problems are strictly related to composites’ porosity and for this reason several authors describe an increase in water absorption, a decrease of freeze–thaw resistance, and permeability to detrimental substances (CO₂, chlorides ions, salts, etc.).^113,197,200 Some authors, however, obtained good results in terms of abrasion and shrinkage resistance.^197,201,202 Finally, attention must also be paid to compaction and segregation of plastics aggregates due to their low specific weight.²⁰⁴ As reported in the literature, a viable strategy to avoid these phenomena is the use of fly ash or silica fume,^205,206 but also using some admixtures^{208–211,212} (superplasticizers, air entraining agents, etc.).

In addition to polymeric fibers and aggregates, recycled polymers are also used as a binder to produce polymer-modified concrete (PMC). The combination of conventional concrete and polymeric resins is able to overcome traditional drawbacks of cementitious materials like durability-related issues, weak adhesion to substrates, and low tensile strength.^213,214 Several authors investigated the possibility of recycling PET by a glycolysis process to produce an unsaturated polyester resin to be used as a binder in concrete or mortar preparation.^215–217 Some interesting and promising results were obtained, such as a sharp decrease in water absorption with increasing PET content, but also an increase in compressive strength with increasing resin content.²¹⁶ Good effects were also reported in terms of porosity reduction, correlating such results to the porosity to water and porosity by N₂ absorption.²¹⁷ More recently, a cement-less polymer concrete was investigated, using only recycled PP and recycled HDPE as binders.²²⁰

Footnotes

Declaration of Conflicting Interests

The authors declare that there is no conflict of interest.

Funding

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

References

Cas

RAF

Wright

. Volcanic successions, modern and ancient: A geological approach to processes, products, and successions. London: Allen & Unwin; 1987.

Walker

Pavía

. Physical properties and reactivity of pozzolans, and their influence on the properties of lime–pozzolan pastes. Mater Struct 2011; 44(6): 1139–1150.

Shi

. Studies on several factors affecting hydration and properties of lime–pozzolan cements. J Mater Civ Eng 2001 Dec; 13(6): 441–445.

Carr

. An investigation on the effect of brick dust on lime-based mortars. MS Thesis, University of Pennsylvania, USA, 1995.

Moropoulou

Cakmak

Labropoulos

et al . Accelerated microstructural evolution of a calcium-silicate-hydrate (C-S-H) phase in pozzolanic pastes using fine siliceous sources: Comparison with historic pozzolanic mortars. Cem Concr Res 2004; 34(1): 1–6.

Ward-Perkins

. Architettura romana. Storia universale dell’architettura. [Roman architecture. Universal history of architecture] Milan: Mondadori Electa. 2003.

Pecchioni

Fratini

Cantisani

. Le malte antiche e moderne: tra tradizione e innovazione. [Ancient and modern mortars: Between tradition and innovation] Bologna: Pàtron; 2008.

Collepardi

. La lezione dei romani: durabilità e sostenibilità delle opere architettoniche e strutturali. [The lesson of the Romans: Durability and sustainability of the architectural and structural works] In: Proceedings of III Convegno AIMAT “Restauro e Conservazione dei Beni Culturali: Materiali e Tecniche Cassino” [Restoration and conservation of cultural heritage: Cassino materials and techniques] Italy, 3–4 October. Cassino, Italy; 2003.

Cagnana

. I leganti, gli intonaci, gli stucchi. [The binders, the plasters, the stuccos] In: Crogiolo

Olcese

(eds) Archeologia dei materiali da costruzione. Manuali per l’Archeologia [Archeology of building materials. Manuals for Archeology] Mantova: S.A.P, 2000. p. 123–154.

10.

Lugli

. La tecnica edilizia romana con particolare riguardo a Roma e Lazio. [The Roman building technique with particular regard to Rome and Lazio] Rome: Scienze e. Roma; 2016.

11.

Giuliani

. L’edilizia nell’antichità. [Construction in antiquity] Rome, Nis; 1990.

12.

Adam

. L’arte di costruire presso i romani. Materiali e techiche. [The art of building of the Romans. Materials and techniques] Milan: Longanesi, 2008.

13.

Procopius Caesariensis. La guerra gotica. Traduzione di Comparetti D [The Gothic war. Translation by Comparetti D] 2nd ed. Milan: Garzanti Libri; 2007.

14.

Jackson

Marra

Deocampo

et al . Geological observations of excavated sand (harenae fossiciae) used as fine aggregate in Roman pozzolanic mortars. J Rom Archaeol 2007; 20: 25–53.

15.

D’Ambrosio

Marra

Cavallo

et al . Provenance materials for Vitruvius’ harenae fossiciae and pulvis puteolanis: Geochemical signature and historical–archaeological implications. J Archaeol Sci Reports 2015; 2: 186–203.

16.

Marcus Vitruvius Pollio. De Architectura. a cura di P.Gros, traduzione e commento di Corso A.[De Architectura. edited by Gros

, translation and commentary by Corso

] Turin: Romano E. Einaudi, 1997.

17.

Greco

. Virtutes materiae: il contributo delle fonti latine nello studio di malte, intonaci e rivestimenti nel mondo romano [Virtutes materiae: The contribution of Latin sources in the study of mortars, plasters and coatings in the Roman world] Cagliari: Sandhi; 2011.

18.

Gaius Plinius Secundus. Naturalis Historia, traduzione e commento di Corso A [Naturalis Historia, translation and commentary of Course A]. In: Muggellesi

Rosati

, Mineralogia e storia dell’arte [Mineralogy and art history] vol.V. Turin: Einaudi; 1988, pp. 33–37.

19.

Collepardi

. Dal calcestruzzo antico a quello moderno. Parte II – Il calcestruzzo romano [From ancient to modern concrete. Part II – Roman concrete]. Enco Journal, anno XIII. 2008; (43).

20.

Moropoulou

Bakolas

Anagnostopoulou

. Composite materials in ancient structures. Cem Concr Compos 2005; 27(2): 295–300.

21.

Giavarini

Ferretti

Santarelli

. Mechanical behaviour and properties. In: Fracture and failure of natural building stones. Dordrecht: Springer Netherlands; 2006. p. 107–120.

22.

Falchi

Müller

Fontana

et al . Influence and effectiveness of water-repellent admixtures on pozzolana–lime mortars for restoration application. Constr Build Mater 2013; 49: 272–280.

23.

Maria

. Use of natural pozzolans with lime for producing repair mortars. Environ Earth Sci 2016; 75(9): 1–8.

24.

Columbu

Sitzia

Ennas

. The ancient pozzolanic mortars and concretes of Heliocaminus baths in Hadrian’s Villa (Tivoli, Italy). Archaeol Anthropol Sci 2017; 9: 523–553.

25.

Gotti

Oleson

Bottalico

et al . A comparison of the chemical and engineering characteristics of ancient roman hydraulic concrete with a modern reproduction of Vitruvian hydraulic concrete. Archaeometry 2008; 50(4): 576–590.

26.

Oleson

Bottalico

Brandon

et al . Reproducing a Roman maritime structure with Vitruvian pozzolanic concrete. J Rom Archaeol 2006; 19: 29–52.

27.

Stanislao

Rispoli

Vola

et al . Contribution to the knowledge of ancient Roman seawater concretes: Phlegrean pozzolan adopted in the construction of the harbour at Soli-Pompeiopolis (Mersin, Turkey). Period di Mineral 2011; 80(3): 471–488.

28.

Jackson

Logan

Scheetz

et al . Assessment of material characteristics of ancient concretes, Grande Aula, Markets of Trajan, Rome. J Archaeol Sci 2009; 36(11): 2481–2492.

29.

Jackson

Ciancio Rossetto

Kosso

et al . Building materials of the theatre of Marcellus, Rome. Archaeometry 2011; 53(4): 728–742.

30.

Jackson

Deocampo

Marra

et al . Mid-Pleistocene pozzolanic volcanic ash in ancient Roman concretes. Geoarchaeology 2010; 25(1): 36–74.

31.

Jackson

Logan

Marra

et al . Composizione e caratteristiche meccaniche dei calcestruzzi della Grande Aula [Composition and mechanical characteristics of the concretes of the Great Hall]. In: Ungaro

Del Moro

Vitti

(eds) I Mercanti di Traiano restituiti: Studi e restauri 2005–2007 [The merchants of Trajan returned: Studies and restorations 2005–2007]. Rome: Palombi Editori. 2010. pp. 145–153.

32.

Izzo

Arizzi

Cappelletti

et al . The art of building in the Roman period (89 B.C.–79 A.D.): Mortars, plasters and mosaic floors from ancient Stabiae (Naples, Italy). Constr Build Mater 2016; 117: 129–143.

33.

Van Deman

. Methods of determining the date of Roman concrete monuments. Am J Archaeol 1912; 16(2): 230–251, http://www.jstor.org/stable/497281

34.

Jackson

Landis

Brune

et al . Mechanical resilience and cementitious processes in Imperial Roman architectural mortar. Proc Natl Acad Sci 2014; 111(52): 18484–18489.

35.

Miriello

Barca

Bloise

et al . Characterisation of archaeological mortars from Pompeii (Campania, Italy) and identification of construction phases by compositional data analysis. J Archaeol Sci 2010; 37(9): 2207–2223.

36.

Silva

Wenk

Monteiro

PJM

. Comparative investigation of mortars from Roman Colosseum and cistern. Thermochim Acta 2005; 438(1–2): 35–40.

37.

Farci

Floris

Meloni

. Water permeability vs. porosity in samples of Roman mortars. J Cult Herit 2005; 6(1): 55–69.

38.

Morricone

Macchia

Campanella

et al . Archeometrical analysis for the characterization of mortars from Ostia Antica. Procedia Chem 2013; 8: 231–238.

39.

Leone

De Vita

Magnani

et al . Characterization of archaeological mortars from Herculaneum. Thermochim Acta 2016; 624: 86–94.

40.

Pavía

Caro

. An investigation of Roman mortar technology through the petrographic analysis of archaeological material. Constr Build Mater 2008; 22(8):1807–1811.

41.

Cocco

Relazioni tra struttura e proprietà delle malte storiche romane. Una lezione dal passato e un tentativo di proiezione nella moderna scienza dei materiali. [Relations between structure and property of Roman historical mortars. A lesson from the past and an attempt to project into modern material science] PhD Thesis. University of Cagliari, Italy, 2007.

42.

Coppola

Coffetti

Crotti

. Use of tartaric acid for the production of sustainable Portland-free CSA-based mortars. Constr Build Mater 2018; 171: 243–249.

43.

Coppola L. Repair and conservation of reinforced concrete tent-church by Pino Pizzigoni at Longuelo-Bergamo (Italy). Int J Archit Herit 2018: 1–9.

44.

Hansen

Doehne

Fidler

et al . A review of selected inorganic consolidants and protective treatments for porous calcareous materials. Stud Conserv 2003; 48(sup1): 13–25.

45.

Salvadori

Dei

. Synthesis of Ca(OH)₂ nanoparticles from diols. Langmuir 2001; 17(8): 2371–2374.

46.

Roy

Bhattacharya

. Synthesis of Ca(OH)₂ nanoparticles by wet chemical method. Micro Nano Lett 2010; 5(2):131–134.

47.

Daniele

Taglieri

. Synthesis of Ca(OH)₂ nanoparticles with the addition of Triton X-100. Protective treatments on natural stones: Preliminary results. J Cult Herit 2012; 13(1): 40–46.

48.

Samanta

Chanda

Das

et al . Synthesis of nano calcium hydroxide in aqueous medium. J Am Ceram Soc 2016; 99(3): 787–795.

49.

Poggi

Toccafondi

Chelazzi

et al . Calcium hydroxide nanoparticles from solvothermal reaction for the deacidification of degraded waterlogged wood. J Colloid Interface Sci 2016; 473: 1–8.

50.

Volpe

Taglieri

Daniele

et al . A process for the synthesis of Ca(OH)₂ nanoparticles by means of ionic exchange resins. EP2880101, 2016.

51.

Taglieri

Felice

Daniele

et al . Analysis of the carbonatation process of nanosized Ca(OH)₂ particles synthesized by exchange ion process. Proc Inst Mech Eng Part N J Nanoeng Nanosyst 2016; 230(1): 25–31.

52.

Taglieri

Daniele

Macera

et al . Nano Ca(OH)₂ synthesis using a cost-effective and innovative method: Reactivity study. J Am Chem Soc 2017; 100(12): 1–13, 5766–5778.

53.

Dei

Salvadori

. Nanotechnology in cultural heritage conservation: Nanometric slaked lime saves architectonic and artistic surfaces from decay. J Cult Herit 2006; 7(2): 110–115.

54.

Natali

Saladino

Andriulo

et al . Consolidation and protection by nanolime: Recent advances for the conservation of the graffiti, Carceri dello Steri Palermo and of the 18th century lunettes, SS. Giuda e Simone Cloister, Corniola (Empoli). J Cult Herit 2014; 15(2): 151–158.

55.

Tortora

Sfarra

Chiarini

et al . Non-destructive and micro-invasive testing techniques for characterizing materials, structures and restoration problems in mural paintings. Appl Surf Sci 2016; 387: 971–985.

56.

Daniele

Taglieri

. Ca(OH)₂ nanoparticle characterization: Microscopic investigation of their application on natural stone. WIT Trans Eng Sci 2011; 72: 55–66.

57.

Daniele

Taglieri

. Nanolime suspensions applied on natural lithotypes: The influence of concentration and residual water content on carbonatation process and on treatment effectiveness. J Cult Herit 2010; 11(1):102–106.

58.

Daniele

Taglieri

Quaresima

. The nanolimes in cultural heritage conservation: Characterisation and analysis of the carbonatation process. J Cult Herit 2008; 9(3): 294–301.

59.

Pesce

Morgan

Odgers

et al . Consolidation of weathered limestone using nanolime. Proc ICE – Constr Mater 2013; 166(4): 213–228.

60.

Rodriguez-Navarro

Suzuki

Ruiz-Agudo

. Alcohol dispersions of calcium hydroxide nanoparticles for stone conservation. Langmuir 2013; 29(36): 11457–11470.

61.

Arizzi

Gomez-Villalba

Lopez-Arce

et al . Lime mortar consolidation with nanostructured calcium hydroxide dispersions: the efficacy of different consolidating products for heritage conservation. Eur J Mineral 2015; 27(3): 311–323.

62.

Taglieri

Daniele

Rosatelli

et al . Eco-compatible protective treatments on an Italian historic mortar (XIV century). J Cult Herit 2017; 25: 135–141.

63.

Meyer

. The greening of the concrete industry. Cem Concr Compos 2009; 31(8): 601–605.

64.

Naik

. Greener concrete using recycled materials. Concr Int 2002; 24(7): 45–49.

65.

Chen

Lee

Young

et al . Glass recycling in cement production – An innovative approach. Waste Manag 2002; 22(7): 747–753.

66.

Carsana

Frassoni

Bertolini

. Pozzolanic performance of recycled glass powder used as a supplementary cementitious material. Cem Concr Compos 2014; (45): 39–45.

67.

Lollini

Redaelli

Bertolini

. Effects of portland cement replacement with limestone on the properties of hardened concrete. Cem Concr Compos 2014; 46: 32–40.

68.

Isfahani

Redaelli

Lollini

et al . Effects of nanosilica on compressive strength and durability properties of concrete with different water to binder ratios. Adv Mater Sci Eng 2016; 2016: 8453567.

69.

Carsana

Gastaldi

Lollini

et al . Improving durability of reinforced concrete structures by recycling wet-ground MSWI bottom ash. Mater Corros 2016; 67(6): 573–582.

70.

Lollini

Redaelli

Bertolini

. A study on the applicability of the efficiency factor of supplementary cementitious materials to durability properties. Constr Build Mater 2016; 120: 284–292.

71.

Lollini

Redaelli

Bertolini

. Investigation on the effect of supplementary cementitious materials on the critical chloride threshold of steel in concrete. Mater Struct 2016; 49(10): 4147–4165.

72.

Shi

Riefler

et al . Characteristics and pozzolanic reactivity of glass powders. Cem Concr Res 2005; 35(5): 987–993.

73.

Shao

Lefort

Moras

et al . Studies on concrete containing ground waste glass. Cem Concr Res 2000; 30(1): 91–100.

74.

Shayan

. Value-added utilisation of waste glass in concrete. Cem Concr Res 2004; 34(1): 81–89.

75.

Shayan

. Performance of glass powder as a pozzolanic material in concrete: A field trial on concrete slabs. Cem Concr Res 2006; 36(3): 457–468.

76.

Coppola

Coffetti

Crotti

. Plain and ultrafine fly ashes mortars for environmentally friendly construction materials. Sustainability 10(3): 874, 1–15.

77.

Idir

Cyr

Tagnit-Hamou

. Pozzolanic properties of fine and coarse color-mixed glass cullet. Cem Concr Compos 2011; 33(1): 19–29.

78.

Schwarz

Cam

Neithalath

. Influence of a fine glass powder on the durability characteristics of concrete and its comparison to fly ash. Cem Concr Compos 2008; 30(6): 486–496.

79.

Nassar

RUD

Soroushian

. Strength and durability of recycled aggregate concrete containing milled glass as partial replacement for cement. Constr Build Mater 2012; 29: 368–377.

80.

De Weerdt

Colombo

Coppola

et al . Impact of the associated cation on chloride binding of Portland cement paste. Cem Concr Res 2015; 68: 196–202.

81.

Ismail

Al-Hashmi

. Recycling of waste glass as a partial replacement for fine aggregate in concrete. Waste Manag 2009; 29(2): 655–659.

82.

Topçu

İB

Canbaz

. Properties of concrete containing waste glass. Cem Concr Res 2004; 34(2): 267–274.

83.

Idir

Cyr

Tagnit-Hamou

. Use of fine glass as ASR inhibitor in glass aggregate mortars. Constr Build Mater 2010; 24(7): 1309–1312.

84.

Corinaldesi

Gnappi

Moriconi

et al . Reuse of ground waste glass as aggregate for mortars. Waste Manag 2005; 25(2). 197–201.

85.

Jin

Meyer

Baxter

. “Glascrete”—Concrete with glass aggregate. ACI Mater J 2000; 97(2): 208–213.

86.

Poutos

Alani

Walden

et al . Relative temperature changes within concrete made with recycled glass aggregate. Constr Build Mater 2008; 22(4): 557–565.

87.

Mladenovič

Šuput

Ducman

et al . Alkali-silica reactivity of some frequently used lightweight aggregates. Cem Concr Res 2004; 34(10): 1809–1816.

88.

Carsana

Bertolini

. Durability of a LWC concrete with expanded glass and silica fume. ACI Mater J 2017; 114(2): 207–213.

89.

Ducman

Mladenovič

Šuput

. Lightweight aggregate based on waste glass and its alkali-silica reactivity. Cem Concr Res 2002; 32(2): 223–226.

90.

Mueller

Sokolova

Vereshagin

. Characteristics of lightweight aggregates from primary and recycled raw materials. Constr Build Mater 2008; 22(4): 703–712.

91.

Nemes

Józsa

. Strength of lightweight glass aggregate concrete. J Mater Civ Eng 2006; 18(5): 710–714.

92.

Kourti

Cheeseman

. Properties and microstructure of lightweight aggregate produced from lignite coal fly ash and recycled glass. Resour Conserv Recycl 2010; 54(11): 769–775.

93.

Taha

Nounu

. Properties of concrete contains mixed colour waste recycled glass as sand and cement replacement. Constr Build Mater 2008; 22(5): 713–720.

94.

Bertolini

Carsana

Yang

. Riciclo del vetro nella produzione del calcestruzzo. [Glass recycling in the production of concrete.] In: Coppola

(ed) Nuovi orizzonti della ricerca. Leganti, calcestruzzi e materiali innovativi per costruire sostenibile: In onore di Giuseppe Frigione. [New horizons of research. Binders, concretes and innovative materials for sustainable construction: In honor of Giuseppe Frigione] Cosenza: Imready, 2015.

95.

Colangelo

Messina

Di Palma

et al . Recycling of non-metallic automotive shredder residues and coal fly-ash in cold-bonded aggregates for sustainable concrete. Compos Part B Eng 2017; 116: 46–52.

96.

Morselli

Santini

Passarini

et al . Automotive shredder residue (ASR) characterization for a valuable management. Waste Manag 2010; 30(11): 2228–2234.

97.

Van Caneghem

Block

Vermeulen

et al . Mass balance for POPs in a real scale fluidized bed combustor co-incinerating automotive shredder residue. J Hazard Mater 2010; 181(1–3): 827–835.

98.

Lin

Chowdhury

Wang

. Catalytic gasification of automotive shredder residues with hydrogen generation. J Power Sources 2010; 195(18): 6016–6023.

99.

Singh

Lingamdinne

Yang

et al . Effect of pH values on recovery of nano particles (NPs) from the fine fraction of automobile shredder residue (ASR): An application of NPs for phenol removal from the water. Process Saf Environ Prot 2017 Jan 1; 105: 51–59.

100.

Belardi

Lavecchia

Ippolito

et al . Recovery of metals from zinc–carbon and alkaline spent batteries by using automotive shredder residues. J Solid Waste Technol Manag 2015; 41(3): 270–274.

101.

Vilardi

Di Palma

. Kinetic study of nitrate removal from aqueous solutions using copper-coated iron nanoparticles. Bull Environ Contam Toxicol 2017; 98(3): 359–365.

102.

Vilardi

Stoller

Verdone

et al . Production of nano zero valent iron particles by means of a spinning disk reactor. Chem Eng Trans 2017; 57: 751–756.

103.

Vilardi

Verdone

Di Palma

. The influence of nitrate on the reduction of hexavalent chromium by zero-valent iron nanoparticles in polluted wastewater. Desalin Water Treat 2017; 1–7.

104.

Marsili

Beyenal

Di Palma

et al . Uranium immobilization by sulfate-reducing biofilms grown on hematite, dolomite, and calcite. Environ Sci Technol 2007; 41(24): 8349–8354.

105.

Marsili

Beyenal

Di Palma

et al . Uranium removal by sulfate reducing biofilms in the presence of carbonates. Water Sci Technol 2005; 52(7): 49–55.

106.

Rossetti

Di Palma

Medici

. Production of aggregate from non-metallic automotive shredder residues. J Hazard Mater 2006 Sep 21; 137(2): 1089–1095.

107.

Rossetti

Di Palma

Ferraro

. Production and characterization of aggregate from nonmetallic automotive shredder residues. J Mater Civ Eng 2011; 23(6): 747–751.

108.

Di Palma

Mancini

Medici

. Lab scale granulation tests of artificial aggregate production from marine sediments and industrial wastes. Chem Eng Trans 2012; 28: 199–204.

109.

Di Palma

Medici

Vilardi

. Artificial aggregate from non metallic automotive shredder residue. Chem Eng Trans 2015; 43: 1723–1728.

110.

Corinaldesi

Mazzoli

Siddique

. Characterization of lightweight mortars containing wood processing by-products waste. Constr Build Mater 2016; 123: 281–289.

111.

Corinaldesi

Nardinocchi

Donnini

. Reuse of recycled glass in mortar manufacturing. Eur J Environ Civ Eng 2016; 20: 140–151.

112.

Corinaldesi

Mazzoli

Moriconi

. Mechanical behaviour and thermal conductivity of mortars containing waste rubber particles. Mater Des 2011; 32(3). 1646–1650.

113.

Corinaldesi

Donnini

Nardinocchi

. Lightweight plasters containing plastic waste for sustainable and energy-efficient building. Constr Build Mater 2015; 94.337–345.

114.

Corinaldesi

Moriconi

. Behaviour of cementitious mortars containing different kinds of recycled aggregate. Constr Build Mater 2009; 23(1): 289–294.

115.

Corinaldesi

Moriconi

. Influence of mineral additions on the performance of 100% recycled aggregate concrete. Constr Build Mater 2009; 23(8): 289–294.

116.

Corinaldesi

. Mechanical and elastic behaviour of concretes made of recycled-concrete coarse aggregates. Constr Build Mater 2010; 24(9): 1616–1620.

117.

Corinaldesi

. Structural concrete prepared with coarse recycled concrete aggregate: From investigation to design. Adv Civ Eng 2011; 2011: 6.

118.

Manzi

Mazzotti

Bignozzi

. Short and long-term behavior of structural concrete with recycled concrete aggregate. Cem Concr Compos 2013; 37(1): 312–318.

119.

Seara-Paz

Corinaldesi

González-Fonteboa

et al . Influence of recycled coarse aggregates characteristics on mechanical properties of structural concrete. Eur J Environ Civ Eng 2016; 20: 123–139.

120.

Coppola

Belz

Dinelli

et al . Prefabricated building elements based on FGD gypsum and ashes from coal-fired electric generating plants. Materials and Structures/Materiaux et Constructions 1996; 29(189): 305–311.

121.

Sani

Moriconi

Fava

et al . Leaching and mechanical behaviour of concrete manufactured with recycled aggregates. Waste Manag 2005; 25(2): 177–82.

122.

Corinaldesi

Moriconi

. Recycling of rubble from building demolition for low-shrinkage concretes. Waste Manag 2010; 30(4): 655–659.

123.

Manzi

Mazzotti

Bignozzi

. Self-compacting concrete with recycled concrete aggregate: Study of the long-term properties. Constr Build Mater 2017; 157: 582–590.

124.

Corinaldesi

Moriconi

. Behavior of beam-column joints made of sustainable concrete under cyclic loading. J Mater Civ Eng 2006; 18(5): 650–658.

125.

Corinaldesi

Letelier

Moriconi

. Behaviour of beam-column joints made of recycled-aggregate concrete under cyclic loading. Constr Build Mater 2011; 25(4): 1877–1882.

126.

Corinaldesi

Giuggiolini

Moriconi

. Use of rubble from building demolition in mortars. Waste Manag 2002; 22(8): 893–899.

127.

Moriconi

Corinaldesi

Antonucci

. Environmentally-friendly mortars: A way to improve bond between mortar and brick. Mater Struct Constr 2003; 36(264): 702–708.

128.

Corinaldesi

. Environmentally-friendly bedding mortars for repair of historical buildings. Constr Build Mater 2012; 35: 778–784.

129.

Fernández-Ledesma

Jiménez

Ayuso

et al . A proposal for the maximum use of recycled concrete sand in masonry mortar design. Mater Constr 2016; 66(321): 75–90.

130.

Colangelo

Cioffi

. Mechanical properties and durability of mortar containing fine fraction of demolition wastes produced by selective demolition in South Italy. Compos Part B Eng 2017; 115: 43–50.

131.

Corinaldesi

. Mechanical behavior of masonry assemblages manufactured with recycled-aggregate mortars. Cem Concr Compos 2009; 31(7): 505–510.

132.

Corinaldesi

Moriconi

. The role of industrial by-products in self-compacting concrete. Constr Build Mater 2011; 25(8): 3181–3186.

133.

Corinaldesi

Moriconi

. Characterization of self-compacting concretes prepared with different fibers and mineral additions. Cem Concr Compos 2011; 33(5): 596–601.

134.

Corinaldesi

Moriconi

. Use of synthetic fibers in self-compacting lightweight aggregate concretes. J Build Eng 2015; 4: 247–254.

135.

Singh

Hui

Singh

et al . Recycling of plastic solid waste: A state of art review and future applications. Compos Part B Eng 2017; 115: 409–422.

136.

Coppola

Lorenzi

Pellegrini

. Rheological and mechanical performances of concrete manufactured by using washing water of concrete mixing transport trucks. American Concrete Institute, ACI Special Publication. 2015; 305: 32.1–32.12.

137.

Baykal

Doven

. Utilization of fly ash by pelletization process; theory, application areas and research results. Resour Conserv Recycl 2000; 30(1): 59–77.

138.

Cioffi

Colangelo

Montagnaro

et al . Manufacture of artificial aggregate using MSWI bottom ash. Waste Manag 2011; 31(2): 281–288.

139.

Colangelo

Cioffi

. Use of cement kiln dust, blast furnace slag and marble sludge in the manufacture of sustainable artificial aggregates by means of cold bonding pelletization. Materials (Basel) 2013; 6(8): 3139–3159.

140.

Coppola

Kara

Lorenzi

. Concrete manufactured with crushed asphalt as partial replacement of natural aggregates. Mater Constr 2016; 66(324): 101–108.

141.

Coppola

Buoso

Coffetti

et al . Electric arc furnace granulated slag for sustainable concrete. Constr Build Mater 2016; 123: 115–119.

142.

Coppola

Lorenzi

Buoso

. Electric arc furnace granulated slag as a partial replacement of natural aggregates for concrete production. In: 2nd international conference on sustainable construction materials and technologies. 2010. June 28–June 30 2010, Università Politecnica delle Marche, Ancona, Italy.

143.

Coppola

Lorenzi

Marcassoli

et al . Impiego di sottoprodotti dell’industria siderurgica nel confezionamento di calcestruzzo per opere in c.a. e c.a.p. [Concrete production by using cast iron industry by-products] Industria Italiana del Cemento 2007; 77(836): 1–10.

144.

Coppola

Coffetti

Crotti

. Pre-packed alkali activated cement-free mortars for repair of existing masonry buildings and conctre structures. Constr Build Mater 2018; 171: 817–828.

145.

Margallo

Aldaco

Irabien

. A case study for environmental impact assessment in the process industry: Municipal Solid Waste Incineration (MSWI). Chem Eng Trans 2014; 39: 613–618.

146.

Gesoğlu

Güneyisi

Öz

HÖ

. Properties of lightweight aggregates produced with cold-bonding pelletization of fly ash and ground granulated blast furnace slag. Mater Struct 2012; 45(10): 1535–1546.

147.

Gomathi

Sivakumar

. Accelerated curing effects on the mechanical performance of cold bonded and sintered fly ash aggregate concrete. Constr Build Mater 2015; 77: 276–287.

148.

Vasugi

Ramamurthy

. Identification of design parameters influencing manufacture and properties of cold-bonded pond ash aggregate. Mater Des 2014; 54: 264–278.

149.

Colangelo

Messina

Cioffi

. Recycling of MSWI fly ash by means of cementitious double step cold bonding pelletization: Technological assessment for the production of lightweight artificial aggregates. J Hazard Mater 2015; 299: 181–191.

150.

Ferone

Colangelo

Messina

et al . Recycling of pre-washed municipal solid waste incinerator fly ash in the manufacturing of low temperature setting geopolymer materials. Materials (Basel) 2013; 6(8): 3420–3437.

151.

Luna Galiano

Fernández Pereira

Vale

. Stabilization/solidification of a municipal solid waste incineration residue using fly ash-based geopolymers. J Hazard Mater 2011; 185(1): 373–381.

152.

Zheng

Wang

et al . Immobilization of MSWI fly ash through geopolymerization: Effects of water-wash. Waste Manag 2011; 31(2): 311–317.

153.

Zhou

et al . Reductive solidification/stabilization of chromate in municipal solid waste incineration fly ash by ascorbic acid and blast furnace slag. Chemosphere 2017; 182: 76–84.

154.

Kourti

Rani

Deegan

et al . Production of geopolymers using glass produced from DC plasma treatment of air pollution control (APC) residues. J Hazard Mater 2010; 176(1–3): 704–709.

155.

Lampris

Lupo

Cheeseman

. Geopolymerisation of silt generated from construction and demolition waste washing plants. Waste Manag 2009; 29(1): 368–373.

156.

Messina

Ferone

Colangelo

et al . Low temperature alkaline activation of weathered fly ash: Influence of mineral admixtures on early age performance. Constr Build Mater 2015; 86: 169–177.

157.

Molino

De Vincenzo

Ferone

et al . Recycling of clay sediments for geopolymer binder production. A new perspective for reservoir management in the framework of Italian legislation: The Occhito reservoir case study. Materials (Basel) 2014; 7(8): 5603–5616.

158.

Migliaccio

Ferrara

Gifuni

et al . Shielding effectiveness tests of low-cost civil engineering materials. Prog Electromagn Res B 2013; 54: 227–243.

159.

Ferone

Liguori

Capasso

et al . Thermally treated clay sediments as geopolymer source material. Appl Clay Sci 2015; 107: 195–204.

160.

Coppola

Courard

Michel

et al . Investigation on the use of foamed plastic waste as natural aggregates replacement in lightweight mortar. Compos Part B Eng 2016; 99: 75–83.

161.

Dehdezi

Erdem

Blankson

. Physico-mechanical, microstructural and dynamic properties of newly developed artificial fly ash based lightweight aggregate – Rubber concrete composite. Compos Part B Eng 2015; 79: 451–455.

162.

La Rosa

Banatao

Pastine

et al . Recycling treatment of carbon fibre/epoxy composites: Materials recovery and characterization and environmental impacts through life cycle assessment. Compos Part B Eng 2016; 104: 17–25.

163.

Kumar

Smith

Fowler

et al . Challenges and opportunities associated with waste management in India. R Soc Open Sci 2017; 4(3): 1–11.

164.

Coppola

Cerulli

Salvioni

. Sustainable development and durability of self-compacting concretes. In: 11th International Conference on Fracture 2005, ICF11 Volume 3, 2005, pp. 2226–2241. Turin; Italy; 20–25 March 2005; Code 93990.

165.

Tang

Brouwers

HJH

. Integral recycling of municipal solid waste incineration (MSWI) bottom ash fines (0–2 mm) and industrial powder wastes by cold-bonding pelletization. Waste Manag 2017; 62: 125–138.

166.

Colangelo

Cioffi

Montagnaro

et al . Soluble salt removal from MSWI fly ash and its stabilization for safer disposal and recovery as road basement material. Waste Manag 2012; 32(6): 1179–1185.

167.

Shi

Zhang

et al . Silicon–aluminum additives assisted hydrothermal process for stabilization of heavy metals in fly ash from MSW incineration. Fuel Process Technol 2017; 165: 44–53.

168.

Lo Presti

. Recycled tyre rubber modified bitumens for road asphalt mixtures: A literature review. Constr Build Mater 2013; 49: 863–881.

169.

European Tyre and Rubber Manufacturers’ Association. End of life tyres – A valuable resource with growing potential. Report, ETRMA, Brussels, Belgium, 2011.

170.

Miskolczi

Nagy

Bartha

et al . Application of energy dispersive X-ray fluorescence spectrometry as multielemental analysis to determine the elemental composition of crumb rubber samples. Microchem J 2008; 88(1): 14–20.

171.

Shu

Huang

. Recycling of waste tire rubber in asphalt and portland cement concrete: An overview. Constr Build Mater 2013; 67: 217–224.

172.

Di Mundo

Petrella

Notarnicola

. Surface and bulk hydrophobic cement composites by tyre rubber addition. Constr Build Mater 2018; 172: 217–224.

173.

Segre

Joekes

. Use of tire rubber particles as addition to cement paste. Cem Concr Res 2000; 30(9): 1421–1425.

174.

Stubblefield

Garrick

et al . Development of waste tire modified concrete. Cem Concr Res 2004; 34(12): 2283–2289.

175.

Garrick

Eggers

et al . Waste tire fiber modified concrete. Compos Part B Eng 2004; 35(4): 305–312.

176.

Lee

Burnett

Miller

et al . Tyre rubber/cement matrix composites. J Mater Sci Lett 1993; 12(13): 967–968.

177.

Wang

Leung

CKY

et al . Properties of rubberized concrete modified by using silane coupling agent and carboxylated SBR. J Clean Prod 2016; 112: 797–807.

178.

Huang

Pang

S-S

et al . Investigation into waste tire rubber-filled concrete. J Mater Civ Eng 2004; 16(3): 187–194.

179.

Eldin

Senouci

. Rubber-tire particles as concrete aggregate. J Mater Civ Eng 1993; 5(4): 478–496.

180.

Batayneh

Marie

Asi

. Use of selected waste materials in concrete mixes. Waste Manag 2007; 27(12): 1870–186.

181.

Siddique

Khatib

Kaur

. Use of recycled plastic in concrete: A review. Waste Manag 2008; 28(10): 1835–1852.

182.

Silva

Betioli

Gleize

PJP

et al . Degradation of recycled PET fibers in Portland cement-based materials. Cem Concr Res 2005; 35(9): 1741–1746.

183.

Pereira

de Oliveira

Jr AL

Fineza

. Optimization of mechanical properties in concrete reinforced with fibers from solid urban wastes (PET bottles) for the production of ecological concrete. Constr Build Mater 2017; 149: 837–848.

184.

Orasutthikul

Unno

Yokota

. Effectiveness of recycled nylon fiber from waste fishing net with respect to fiber reinforced mortar. Constr Build Mater 2017; 146: 594–602.

185.

Kim

JHJ

Park

Lee

et al . Effects of the geometry of recycled PET fiber reinforcement on shrinkage cracking of cement-based composites. Compos Part B Eng 2008; 39(3): 442–450.

186.

Borg

Baldacchino

Ferrara

. Early age performance and mechanical characteristics of recycled PET fibre reinforced concrete. Constr Build Mater 2016; 108: 29–47.

187.

Fernández

Payá

Borrachero

et al . Degradation process of postconsumer waste bottle fibers used in Portland cement–based composites. J Mater Civ Eng 2017 29(10): 4017183.

188.

Pešić

Živanović

Garcia

et al . Mechanical properties of concrete reinforced with recycled HDPE plastic fibres. Constr Build Mater 2016; 115: 362–370.

189.

Kurup

Kumar

. Novel fibrous concrete mixture made from recycled PVC fibers from electronic waste. J Hazardous, Toxic, Radioact Waste 2017; (2): 4016020.

190.

Kurup

Senthil Kumar

. Effect of recycled PVC fibers from electronic waste and silica powder on shear strength of concrete. J Hazardous, Toxic, Radioact Waste 2017; (3): 6017001.

191.

Coppola

Cadoni

Forni

et al . Mechanical characterization of cement composites reinforced with fiberglass, carbon nanotubes or glass reinforced plastic (GRP) at high strain rates. Appl Mech Mater 2011; 82: 190–195.

192.

Coppola

Scarfato

Incarnato

et al . Durability and mechanical properties of nanocomposite fiber reinforced concrete. CSE J City Safety Energy 2013; 127–36.

193.

Pacheco-Torgal

Jalali

. Nanotechnology: Advantages and drawbacks in the field of construction and building materials. Constr Build Mater 2011; 25(2): 582–590.

194.

Coppola

Di Maio

Scarfato

et al . Use of polypropylene fibers coated with nano-silica particles into a cementitious mortar. AIP Conf Proc 2015; 1695(20056): 4937334.

195.

López-Buendía

Romero-Sánchez

Climent

et al . Surface treated polypropylene (PP) fibres for reinforced concrete. Cem Concr Res 2013; 54: 29–35.

196.

Herrero

Mayor

Hernández-Olivares

. Influence of proportion and particle size gradation of rubber from end-of-life tires on mechanical, thermal and acoustic properties of plaster–rubber mortars. Mater Des 2013; 47: 633–642.

197.

Saikia

De Brito

. Use of plastic waste as aggregate in cement mortar and concrete preparation: A review. Constr Build Mater 2012; 34: 385–401.

198.

Choi

Moon

Kim

et al . Characteristics of mortar and concrete containing fine aggregate manufactured from recycled waste polyethylene terephthalate bottles. Constr Build Mater 2009; 23(8): 2829–2835.

199.

Choi

Moon

Chung

et al . Effects of waste PET bottles aggregate on the properties of concrete. Cem Concr Res 2005; 35(4): 776–781.

200.

Senhadji

Escadeillas

Benosman

et al . Effect of incorporating PVC waste as aggregate on the physical, mechanical, and chloride ion penetration behavior of concrete. J Adhes Sci Technol 2015; 29(7): 625–640.

201.

Turatsinze

Bonnet

Granju

. Potential of rubber aggregates to modify properties of cement based-mortars: Improvement in cracking shrinkage resistance. Constr Build Mater 2007; 21(1): 176–181.

202.

Turatsinze

Hameed

et al . Effects of rubber aggregates from grinded used tyres on the concrete resistance to cracking. J Clean Prod 2012; 23(1): 209–215.

203.

Wang

Meyer

. Performance of cement mortar made with recycled high impact polystyrene. Cem Concr Compos 2012; 34(9): 975–981.

204.

Albano

Camacho

Hernández

et al . Influence of content and particle size of waste pet bottles on concrete behavior at different w/c ratios. Waste Manag 2009; 29(10): 2707–2716.

205.

Monosi

Troli

Coppola

et al . Water reducers for the high alumina cement-silica fume system. Materials and Structures/ Materiaux et Constructions 1996; 29(194): 639–644.

206.

Coppola

Troli

Collepardi

et al . Innovative cementitious materials from HPC to RPC - Part II. The effect of cement and silica fume type on the compressive strength of reactive powder concrete | [Materiali cementizi innovativi: Dagli HPC verso gli RPC - Parte II. L’influenza del cemento e del fumo di silice sulla resistenza meccanica del reactive powder concrete]. Industria Italiana del Cemento 1996; 66(707): 112–125.

207.

Coppola

Coffetti

Lorenzi

. Cement-based renders manufactured with phase-change materials: Applications and feasibility. Adv Mater Sci Eng 2016.

208.

Coppola

Lorenzi

Kara

et al . Performance and compatibility of phosphonate-based superplasticizers for concrete. Buildings 2017; 7(3): 62–72.

209.

Coppola

Lorenzi

Garlati

et al . The rheological and mechanical performances of concrete manufactured with blended admixtures based on phosphonates. Key Eng Mat 2016; 674: 159–164.

210.

Coppola

Buoso

Lorenzi

. Compatibility issues of NSF-PCE superplasticizers with several lots of different cement types (long-term results). Kuei Suan Jen Hsueh Pao/ J Chinese Ceram Soc] 2010; 38(9): 1631–1637.

211.

Zhang

Collepardi

Coppola

et al . Ottimizzazione del calcestruzzo ad alta resistenza meccanica con superfluidificante per la diga delle Tre Gole in Cina. [Optimization of the high-strength superplasticized concrete of the Three-Gorge dam in China] Industria Italiana del Cemento 2003; 73: 58–69.

212.

Coppola

Coffetti

Crotti

. Innovative carboxylic acid waterproofing admixture for self-sealing watertight concretes. Constr Build Mater 2018; 171: 817–824.

213.

Bedi

Chandra

Singh

. Mechanical properties of polymer concrete. 2013; 2013(390): 12.

214.

Tukimat

NNA

Sarbini

Ibrahim

et al . Fresh and hardened state of polymer modified concrete and mortars – A review. In: International symposium on civil and environmental engineering 2016. MATEC web Conf. Volume 103, 2017. Article Number 01025, pages 10, Section: Sustainable and Advanced Construction Materials, Published online: 5 April 2017.

215.

Mahdi

Abbas

Khan

. Strength characteristics of polymer mortar and concrete using different compositions of resins derived from post-consumer PET bottles. Constr Build Mater 2010; 24(1): 25–36.

216.

Miranda Vidales

Narvez Hernendez

Tapia Lopez

et al . Polymer mortars prepared using a polymeric resin and particles obtained from waste PET bottle. Constr Build Mater 2014; 65: 376–383.

217.

Mendivil-Escalante

Gómez-Soberón

Almaral-Sánchez

et al . Metamorphosis in the porosity of recycled concretes through the use of a recycled polyethylene terephthalate (PET) additive. Correlations between the porous network and concrete properties. Materials (Basel) 2017; 10(2): 176–195.

218.

Dalhat

Al-Abdul Wahhab

. Cement-less and asphalt-less concrete bounded by recycled plastic. Constr Build Mater 2016; 119: 206–214.

Binders alternative to Portland cement and waste management for sustainable construction – Part 2

Abstract

Keywords

Introduction

Traditional and innovative Portland-free lime-based mortar for conservation of historical heritage

Traditional historic mortars

Nanolime in conservation of cultural heritage

Waste management and recycling

Recycled glass

Aggregates from automotive shredder residues

Recycled aggregates in concrete

Artificial aggregates in concrete

Recycled tires in concrete production

Recycled polymers in cementitious mixtures

Footnotes

Declaration of Conflicting Interests

Funding

References