冻结井壁纤维混杂与微膨胀高性能混凝土配制与抗裂试验

Preparation and Crack Resistance Test of High Performance Concrete with Fiber Hybrid and Micro Expansion Freezing Shaft Lining

为解决深厚表土层冻结井壁混凝土开裂渗漏水难题,提出采用纤维混杂与微膨胀高性能混凝土。以冻结井壁普通混凝土配合比为基础,采用正交试验法,考察了水胶比、膨胀剂掺量、聚乙烯醇纤维掺量及仿钢纤维掺量对纤维混杂与微膨胀高性能混凝土的抗压强度和劈裂抗拉强度的影响,综合平衡确定试验的最佳配合比为水:水泥:NF-F:膨胀剂:聚乙烯醇纤维:聚丙烯仿钢纤维:砂:玄武岩碎石=166.112:410:130:32.8:1.092:5:615.992:1095.096。抗裂试验结果表明,纤维混杂与膨胀剂复合混凝土具有优良的抗裂性能。

To solve the leakage problem of concrete cracking and seepage in the freezing shaft lining of deep topsoil,it is proposed to use hybrid fibers and micro expansion high-performance concrete.Based on the normal concrete mix ratio of the frozen shaft lining,the orthogonal test method was used to investigate the effect of the water-to-binder ratio,the amount of expansion agent,the amount of polyvinyl alcohol fiber and the amount of imitation steel fiber on the compressive strength and splitting tensile strength of fiber hybrid and micro expansion high performance concrete.Comprehensive balance determines that the best mix ratio of this test is water:cement:NF-F:expansion agent:polyvinyl alcohol fiber:polypropylene imitation steel fiber:sand:basalt gravel=166.112:410:130:32.8:1.092:5:615.992:1095.096.The crack resistance test results show that the fiber hybrid and expansion agent composite concrete has excellent crack resistance.