Experimental Study on Non-Autoclaved PHC Pile Concrete Applying Polycarboxylate Superplasticizer

Traditional PHC pile production adopts two-step curing with the disadvantages of high energy consumption, considerable carbon emissions, and easy cracking during construction. In addition, non-autoclaved pipe pile studies involve problems such as adoption of naphthalene based superplasticizer and lengthy coated curing duration, thus leading to their few applications. In order to solve the problems, the study on non-autoclaved PHC pile was conducted to systematically study the impacts of curing system, water-binder ratio, and admixture composition on concrete strength, ratio of tensile and compressive strength, and chloride ion resistance at different ages. Study results show that through the use of a polycarboxylate superplasticizer, an optimal 8-hour curing system and concrete mix ratio, the strength of non-autoclaved concrete reached 93.2MPa within one day, with the ratio of tensile and compressive strength of 6.07%, the coulomb electric flux of 85C, and the chloride migration coefficient of 0.54×10-12m2/s.