考虑箍筋锈蚀影响的约束混凝土抗压强度模型

Compressive strength model for confined concrete considering influence of hoop corrosion

基于加速锈蚀箍筋约束混凝土试件的单轴受压试验,获取了36组不同锈蚀程度条件下箍筋约束混凝土的抗压强度试验数据,分析了配箍形式和箍筋质量锈蚀率等因素对抗压强度和破坏形态的影响规律,结合混凝土材料的极限强度面和破坏准则,建立了锈蚀箍筋约束混凝土的抗压强度模型,并验证了模型的有效性。分析表明:随着箍筋质量锈蚀率的增大,约束混凝土的抗压强度逐渐减小;当配箍形式相同时,箍筋间距越大,箍筋质量锈蚀率对抗压强度的影响越显著;当箍筋间距相同时,箍筋质量锈蚀率对配置方形箍试件的抗压强度影响程度大于配置棱形箍试件;当箍筋质量锈蚀率分别约为16.7%、10.0%和30.0%时,大部分方形箍、棱形箍和螺旋箍在试件轴压破坏位置处发生断裂。

Uniaxial compression test of concrete specimens confined by accelerated corroded hoops was carried out and 36 sets of test data of compressive strength for confined concrete with different corrosion levels were obtained.The influences of factors such as the configuration of hoops and hoop mass corrosion rate on the compressive strength and failure mode of specimens were analyzed.Meanwhile,a computational model for compressive strength of concrete confined by corroded hoops was developed by combining the ultimate strength surface and failure criterion of concrete material.Finally,the applicability of the proposed model was validated based on experimental data.The analysis results show that the compressive strength of confined concrete decreases with the increase of hoop mass corrosion rate.When the configuration of hoops is the same,the influence of hoop mass corrosion rate on the compressive strength exhibits more significantly when the space of hoops is larger.When the space of hoops is the same,the hoop mass corrosion rate will affect the compressive strength of the specimens with square hoops larger than that of the specimens with prismatic hoops.When the hoop mass corrosion rate is about 16.7%,10.0%and 30.0%,most of the square,prismatic and spiral hoops are broken at the axial compression failure position of specimens respectively.