海砂再生混凝土受压力学性能试验研究与分析

Experim ental study and analysis on sea sand recycled concrete underaxialcom pression

以再生粗骨料取代率和海砂氯离子含量为试验参数,完成了海砂再生混凝土轴压性能试验,分析了再生粗骨料取代率、海砂氯离子含量对试件破坏特征和受力变形性能的影响。结果表明:海砂再生混凝土受力全过程与普通混凝土(河砂天然骨料混凝土)相似,主要破坏模式为剪切型破坏;但试件最终破坏状态略有差异。海砂再生混凝土抗压强度高于普通混凝土,其值随着再生粗骨料取代率的增大而降低,随着海砂氯离子含量的增大而增大。试件弹性模量随再生粗骨料取代率的增大而减小,而氯离子含量影响与之相反。海砂再生混凝土峰值应变略低于普通混凝土,其值随着再生骨料与海砂含量的变化而变化。海砂氯离子含量对混凝土性能的影响随着取代率的提高而不断下降。最后,通过对比发现,在海砂与再生粗骨料双因素耦合作用下,试件力学性能改变明显。所得试验结果为海砂再生混凝土在工程上的应用提供了基础。

It presents an axial compression test for the sea sand recycled concrete(SSRC).The main test parameters are recycled coarse aggregate(RCA)replacement percentage and sea sand chloride ion content(CIC).The effects of RCA replacement percentage and CIC on the failure pattern of specimens and the load-deformation behaviors were investigated.Test results show that the loading process of SSRC is similar to that of ordinary concrete(river sand natural coarse aggregate concrete).The main failure mode of specimen is shear failure,while the failure state of SSRC is slightly different from that of ordinary concrete.The prismatic compressive strength of SSRC is higher than that of ordinary concrete,and its value decreases with the increase of the RCA replacement percentage and the decrease of the sea sand CIC.The elastic modulus decreases with the increase of the RCA replacement percentage,while the effect of CIC on the elastic modulus is opposite to that of RCA content.The peak strain of SSRC is lower than that of ordinary concrete,and it changes with the variation of RCAand sea sand contents.The influence of sea sand CIC on the properties of SSRC decreases with increasing of RCAreplacement percentage.Finally,it is found that the mechanical properties of the concrete are obviously changed under the influence of the coupling factors of the sea sand and the recycled coarse aggregate.The analyses of experimental results provide a basis for the application of sea sand recycled concrete.