Volume Deformation Control of Concrete for Hydraulic Structures Using Polyurethane-Modified Polycarboxylate...

As a widely used building material, the performance of concrete has a far-reaching impact on the quality and durability of hydraulic engineering. Polycarboxylate superplasticizer (PCE) plays an increasingly important role in concrete engineering because of its unique high-efficiency water-reducing performance and the improvement effect on concrete performance. In this paper, the application and influence of polycarboxylate in concrete, including its chemical structure, action mechanism and application effect, are reviewed. It is found that polycarboxylate can greatly reduce the shrinkage of concrete and control its volume deformation. The objective of this review is to elucidate the mechanisms by which polyurethane-modified polycarboxylate (MPCE) reduces autogenous and drying shrinkage in concrete and to demonstrate its advantages over conventional PCE. On this basis, we focus on the core research object of MPCE and discuss in depth its effect on reducing the surface tension of concrete pore solution and the intrinsic mechanism of regulating volume deformation. The research clarifies the superior performance of MPCE over ordinary PCE in inhibiting autogenous shrinkage and drying shrinkage in concrete, which provides a targeted scientific basis for the practical application of MPCE in concrete volume deformation control.