混凝土早龄期力学性能的影响因素  

Influential factors on mechanical property of concrete at early-age

作　　者：周勇[1] 高杰[1] 屈文俊[1] 

机构地区：[1]同济大学建筑工程系,上海200092

出　　处：《铁道科学与工程学报》2015年第6期1323-1330,共8页Journal of Railway Science and Engineering

基　　金：国家自然科学基金青年科学基金资助项目(51208373);上海市自然科学基金资助项目(14ZR1443300)

摘　　要：混凝土在龄期12 h^2 d表现出明显的塑性,为了避免受力后引起较大的侧向位移,采用一种无损检测方法——冲击共振法,可以快速准确地测出混凝土早龄期动态弹性模量,并通过它与静力受压弹性模量的线性关系推算出静力受压弹性模量。试验研究骨料体积含量、粗骨料级配、粗骨料种类、水灰比和养护温度对混凝土轴心抗压强度和弹性模量的影响,进一步分析在相同龄期时,哪些因素是重要因素。研究得出水灰比是轴心抗压强度的重要影响因素,骨料体积含量是弹性模量的重要影响因素。同时,采用多元回归分析建立上述影响因素与强度和弹性模量相关关系的数学表达式。The concrete at the age of 12 h 2 d presents obvious plasticity. In order to avoid large lateral deformation,a nondestructive method—impact resonance method was applied,which can give the dynamic modulus of concrete at early age directly. The relationship between the modulus of elasticity of concrete and the dynamic modulus of concrete is linear. Therefore the modulus of elasticity of concrete can be calculated from the dynamic modulus of concrete. Meanwhile,the influences of the volume contents of aggregate,the grade and type of coarse aggregate,the water- cement ratio and the curing temperature on the prismatic compressive strength and the modulus of elasticity of concrete at early age were investigated. Furthermore,the importance of each influential factors were researched at the same age. It is proved that the water- cement ratio is the most important on the prismatic compressive strength and the volume content of aggregate is the most important on modulus of elasticity of concrete. The relationship between the influential factors and the prismatic compressive strength or modulus of elasticity of concrete is established by multivariate regression analysis.

关 键 词：早龄期 冲击共振法 影响因素 重要性分析 多元回归分析 

分 类 号：TU502.6[建筑科学—建筑技术科学]