沙漠砂再生骨料混凝土轴压应力-应变曲线研究  

Study on stress-strain curve of desert sand recycled aggregate concrete under axial compression

作　　者：陈育志[1,2] 陈晨 宣卫红[1] 严文龙 CHEN Yuzhi;CHEN Chen;XUAN Weihong;YAN Wenlong(College of Architectural Engineering,Jinling Institute of Technology,Nanjing 211169,China;College of Civil and Transportation Engineering,Hohai University,Nanjing 210098,China;College of Civil Engineering,Southeast University,Nanjing 211189,China)

机构地区：[1]金陵科技学院建筑工程学院,南京211169 [2]河海大学土木与交通学院,南京210098 [3]东南大学土木工程学院,南京211189

出　　处：《建筑结构》2023年第21期101-106,共6页Building Structure

基　　金：国家自然科学基金项目(51708265);江苏省产学研合作项目(BY2021059);金陵科技学院高层次人才科研项目(jit-b-202210)。

摘　　要：为研究沙漠砂对再生混凝土力学性能的影响,以再生骨料为粗骨料,分别采用0%、20%、40%和60%的沙漠砂取代普通河砂制备沙漠砂再生骨料混凝土圆柱体试件并开展轴心受压试验。采用试件表面粘贴应变片和外夹式LVDT位移传感器分别采集荷载峰前和峰后应变,消除试件开裂以及加载板间隙等因素对测量精度的影响,从而更准确地测得轴压应力-应变全曲线。研究结果表明:随着沙漠砂替代率的增加,沙漠砂再生骨料混凝土抗压强度、弹性模量和横向变形系数呈现先增大后降低的趋势,其中抗压强度和横向变形系数在沙漠砂掺量为20%时最大,弹性模量在沙漠砂掺量为40%时最大。沙漠砂再生骨料混凝土应力-应变全过程曲线的形状与普通混凝土相似,基于Carrerira D J模型和过镇海模型建立了沙漠砂再生骨料混凝土应力-应变本构方程,计算结果与试验结果吻合较好。To study the effect of desert sand on the mechanical properties of recycled concrete,axial compressive tests were conducted on cylindrical specimens of desert sand recycled aggregate concrete(DSRAC).The coarse aggregates in the specimens were made of recycled aggregates,and desert sand was used to replace river sand as fine aggregates at percentages of 0%,20%,40%,and 60%,respectively.Strain gauges affixed to the surface of the specimens and external clamp-type LVDTs were employed to collect strain data before and after the peak load.This approach mitigated the influence of factors such as specimen cracking and the gap between the loading plates on measurement accuracy,thereby enabling a more precise determination of the axial stress-strain full curve.The research results indicate that with an increasing substitution rate of desert sand,the compressive strength,modulus of elasticity,and lateral deformation coefficient of DSRAC initially increase and then decrease.The compressive strength and the lateral deformation coefficient reach their maximum values when the desert sand content is 20%,while the modulus of elasticity reaches its highest when the desert sand content is 40%.The shape of the stress-strain curves of DSRAC resembles that of ordinary concrete.Constitutive equations for the stress-strain of DSRAC were established based on the Carrerira D J model and the Guo Zhenhai model,and the calculated results are in good agreement with the experimental data.

关 键 词：沙漠砂 再生骨料混凝土 轴心受压 应力-应变曲线 本构模型 

分 类 号：TU528[建筑科学—建筑技术科学]