配合比参数对箱梁混凝土开裂性能的影响

Influence of Mix Proportion Parameters on Cracking Performance of Box Girder Concrete

摘要: 大量工程实例表明，塑性收缩与干燥收缩是导致箱梁混凝土裂缝产生的主要原因。本文研究了水胶比、砂率、单位用水量、外加剂掺量等配合比参数对箱梁混凝土开裂性能的影响，提出了提高抗塑性收缩和干燥收缩开裂性能配合比设计方法：适当减小水胶比、降低砂率、减少单位用水量和优化级配，并评估了各个配合比参数对混凝土开裂性的影响程度，排序为拌合物流动性、单位用水量、水胶比、砂率和骨料级配。

Abstract: A large number of engineering examples show that plastic shrinkage and drying shrinkage are the main reasons for the cracks of box girder concrete. This article studies the influence of mix proportion parameters on the cracking performance of box girder concrete, such as the water binder ratio, sand ratio, water unit content, the amount of admixture, etc., puts forward the mixture ratio design method of improving plastic shrinkage and dry shrinkage crack resistance: appropriately reducing the water cement ratio, the sand rate and the water consumption, and optimizing gradation and evaluates the influence degree of parameters on concrete cracking and its order is: the fluidity of the mixture, the water unit consumption, water binder ratio, sand ratio and aggregate gradation.