机制砂高强混凝土强度和弹性模量试验研究

Experimental study on strength and elastic modulus of high strength concrete with machine-made sand

为研究采用机制砂配制高强混凝土的力学性能,对机制砂替代率为30%~100%、强度等级C60以上混凝土进行了不同龄期的立方体和棱柱体抗压强度、劈裂抗拉强度和弹性模量试验。分析了机制砂替代率对混凝土强度、棱柱体与立方体抗压强度比值以及弹性模量的影响。结果表明,在其他材料和用水量相同条件下,用机制砂部分或全部替代天然砂的混凝土强度和弹性模量均有所提高;棱柱体与立方体抗压强度比值仍可按现行《混凝土结构设计规范》(GB 50010—2010)的相关公式计算。同时,通过试验数据的回归分析,提出了考虑机制砂替代率影响的弹性模量计算公式,该公式的计算结果与试验结果吻合良好。

In order to study the mechanical properties of high strength concrete with machine-made sand,tests for the cubic and prism compressive strength,the splitting tensile strength and elastic modulus of concrete with strength grade above C60 and the replacement ratio of machine-made sand from 30%to 100%were carried out.The influence of the replacement ratio of machine-made sand on the strength of concrete,the ratio of prism compressive strength to cubic compressive strength,and the elastic modulus was analyzed.The results show that the strength and elastic modulus of concrete,which natural sand was replaced with the machine-made sand partially or completely,are improved under the same conditions of other materials and water consumption.The ratio of prism compressive strength to cube compressive strength the can still be calculated according to the relevant formulas of the current Code for the design of concrete structures(GB 50010—2010).At the same time,through the regression analysis of the test data,elastic modulus calculation formula considering the influence of the replacement ratio of machine-made sand was proposed,The calculation results of the formula are in good agreement with the test results.