There is a problem that accelerator make the early compressive strength of mortar develop slowly. This study to utilize thickening agent and developed accelerator to improve the early compressive strength. The research findings demonstrated that with the addition of accelerator, a large amount of hydration products is formed in the paste. The dosage of PAH was 2%, the strength of the mortar reached 13.96 MPa at 1 d. The primary cause is that the PAH formed a granule-particle bridge structure, which made the structure of hydration products denser, thus improving the early compressive strength. It provides the value for the application of accelerator and thickener in the shotcrete field.
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