高致密高强橡胶混凝土的力学性能

Mechanical properties of high-density and high-strength concrete with rubber

考虑深部煤炭开采等深部地下工程的高渗透压以及剧烈扰动的工况需求,对地下混凝土材料韧性和致密性等性能提出更高要求。因此基于最紧密堆积模型,完成了高致密橡胶混凝土配合比设计,并在此基础上控制橡胶颗粒掺量和粒径,研究了橡胶掺量和橡胶粒径对其养护7、14、28 d后力学性能的影响。研究结果表明:高致密橡胶混凝土各项基础力学性能皆优于普通橡胶混凝土,橡胶掺量的增加会导致高致密橡胶混凝土抗压强度和弹性模量下降,抗折强度为先增后减,劈裂抗拉强度呈现波动下降趋势,且高致密的混凝土结构能够有效改善橡胶掺入带来的抗压强度和弹性模量下降。综合试验结果,20%橡胶粉掺量下的高致密橡胶混凝土表现出最佳的力学性能。

Considering the working conditions of high permeability and severe disturbance of deep underground projects such as deep coal mining,higher requirements are put forward for the toughness and compactness of underground concrete materials.Therefore,based on the most compact packing model,the mix proportion design of high-density rubber concrete was completed,the rubber particle content and particle size were controlled,and the effects of rubber content and particle size on the mechanical properties of the concrete after curing for 7 d,14 d,and 28 d were studied.The research results showed that the mechanical properties of each foundation of high-density rubber concrete were better than ordinary rubber concrete.The increase of rubber content would lead to the decrease of the compressive strength and elastic modulus of high-density rubber concrete.The flexural strength first increased and then decreased,and the splitting tensile strength presented a downward trend of fluctuation.The high-density concrete structure could effectively improve the decrease of compressive strength and elastic modulus caused by rubber content.Comprehensive test results showed that the high-density rubber concrete with 20%rubber powder has the best mechanical properties.