Influence of lateral impact on reinforced concrete piers under drying-wetting cycle and chloride ion corrosion environment

Abstract

In order to study the influence of lateral impact on reinforced concrete piers in marine environment, drop hammer impact tests were carried out on piers with different corrosion rates obtained from drying-wetting cycle and chloride ion corrosion experiment to study the crack propagation process and failure modes of piers. Then by numerical simulation, the influences of impact velocity, impact mass, compressive strength of concrete and impact number on the performance of corroded piers were studied. The results showed that the failure modes of piers with different corrosion rates under lateral impact were different. The non-corrosive and low corrosion rate piers were destroyed by the bending shear which was jointly controlled by the transverse bending crack and oblique shear crack. The medium corrosion rate pier was the bending shear failure caused by oblique shear crack. The high corrosion rate pier was the joint action of bending shear crack and rust expansion crack. The increase of impact velocity, impact mass and impact number will increase the maximum deflection and the damage of the corroded piers, but the increase degrees were different. The increase was largest when the impact number was increased. Increasing impact number from 1 to 5, the maximum deflection increased by 26.3 times and the number of damage element increased by 4.3 times. Increasing the compressive strength of concrete will decrease the damage of pier, but with less degree. Increasing the compressive strength from 25 to 45 MPa, the maximum deflection and number of damage element were decreased by 10.7% and 9.4% respectively.