摘要
为了研究石粉含量对机制砂混凝土力学性能的影响,以广西大石山区机制砂为研究对象,开展了机制砂混凝土和天然砂混凝土的力学性能对比试验,研究了石粉含量(质量分数)分别为0%,3%,6%,9%,12%时对机制砂混凝土立方体抗压强度、轴心抗压强度、劈裂抗拉强度、弹性模量和抗折强度的影响,并与天然砂混凝土进行对比。结果表明:机制砂混凝土的力学性能数值随石粉含量增加先变大再变小,石粉含量为3%时机制砂混凝土力学性能数值最大,石粉含量超过3%时会削弱混凝土的密实度、骨架作用和水泥砂浆强度,利用不同地域、不同石材制作机制砂混凝土时,应通过试验确定最佳石粉含量;石粉含量大于6%时,机制砂混凝土力学性能数值小于天然砂混凝土,实际工程中应控制石粉含量上限;建议广西大石山区石灰岩机制砂混凝土换算系数取为0.68;提出的机制砂混凝土立方体抗压强度与弹性模量之间换算公式的理论值与实测值的平均比值为0.982,理论值与实测值相对偏差的平均值为1.88%;所得结论可为机制砂混凝土的研究与推广应用提供借鉴和参考。
In order to study the influence of stone powder content on mechanical properties of manufactured sand concrete, manufactured sand from Dashi mountain area in Guangxi was taken as research object. Comparison experiments for mechanical properties of natural sand concrete and manufactured sand concrete were carried out. The influences of stone powder contents(mass fraction) 0%, 3%, 6%, 9% and 12% on cubic compression strength, axial compression strength, splitting tensile strength, elasticity modulus and flexural strength were studied and compared with natural sand concrete. The results show that, with increase of stone powder content, mechanical properties’ value of manufactured sand concrete first increases and then decreases, and mechanical properties’ value reaches peak when stone powder content is 3%. When stone powder content exceeds 3%, compactness, skeleton effect and cement mortar strength of concrete are weakened. When manufactured sand concrete is made by different stone materials in different regions, the optimum stone powder content should be determined through experiments. When stone powder content is more than 6%, mechanical properties’ value of manufactured sand concrete is less than that of natural sand concrete, in practical engineering, upper limit of stone powder content should be controlled. It is suggested that conversion coefficient of limestone manufactured sand concrete from Dashi mountain area in Guangxi is 0.68.Conversion formula of manufactured sand concrete between cubic compression strength and elastic modulus is proposed. The average ratio of theoretical values to measured values is 0.982, and average relative deviation between theoretical values and measured values is 1.88%. The conclusion can provide reference for research and application of manufactured sand concrete.
作者
谢开仲
王红伟
肖杰
杨丹
XIE Kai-zhong;WANG Hong-wei;XIAO Jie;YANG Dan(College of Civil Engineering and Architecture,Guangxi University,Nanning 530004,Guangxi,China;Key Laboratory of Engineering Disaster Prevention and Structural Safety of Ministry Education,Guangxi University,Nanning 530004,Guangxi,China;Guangxi Key Laboratory of Engineering Disaster Prevention and Structural Safety,Guangxi University,Nanning 530004,Guangxi,China)
出处
《建筑科学与工程学报》
CAS
北大核心
2019年第5期31-38,共8页
Journal of Architecture and Civil Engineering
基金
国家自然科学基金重点项目(51738004)
国家自然科学基金项目(51868007,51368005,51878186)
广西科技计划项目(桂科AD17195096)
四川省科技计划项目(2018GZ0052)
广西大学科学研究基金项目(XBZ100762)
关键词
机制砂混凝土
天然砂混凝土
石粉
力学性能
manufactured sand concrete
natural sand concrete
stone powder
mechanical property
