EPS轻骨料混凝土工作性能改善与评价方法研究

Methods available for improving and evaluating the workability of EPS lightweight concrete

EPS轻骨料混凝土是一种具有质轻、隔热保温等特点的功能性水泥基材料,但由于EPS颗粒表面憎水和密度小,致使该种材料在搅拌和输送过程中存在骨料上浮分离等问题,严重影响了其工作性能和质量均匀性。在建立EPS轻骨料混凝土工作性能评价方法的基础上,从材料组成出发,探讨了改善EPS轻骨料混凝土工作性能的措施。研究结果表明,采用流动度、坍落度和分层度3个指标综合评判EPS轻骨料混凝土的工作性,简单易行,可操作性强;通过水灰比、EPS颗粒用量以及粉煤灰和纤维素醚掺量等参数的优化,可以制备工作性好、质量均匀的EPS轻骨料混凝土。

EPS lightweight concrete is functional cement based material with light weight and thermal insulation. However, during the mixing and transportation process, segregation exists due to water repellent and density of EPS particle surface that has a strong impact on its workability and homogeneity. Measures for improving the workability of EPS lightweight concrete were discussed based on the es- tablishment of EPS lightweight concrete workability evaluating method and from the view point of material composition. The results show that a combination of the test result of fluidity, slump and degree of segregation can well and easily evaluate the workability of EPS lightweight concrete. A homogeneous EPS lightweight concrete with good workability can be prepared by properly adjusting water to cement ratio, content of EPS particles and addition of fly ash and hydroxy, ethyl methyl cellulose.