约束作用下箍筋锈蚀对再生混凝土抗压强度的影响研究

Research on the influence of hoop corrosion under constraint on the compressive strength of recycled concrete

通过加速锈蚀箍筋约束再生混凝土试件的单轴受压试验,研究了配箍形式、箍筋锈蚀率等因素对抗压强度和破坏形态的影响。并结合再生混凝土的极限强度面和破坏准则,建立了锈蚀箍筋约束再生混凝土的抗压强度模型,验证了模型的有效性。结果表明:随着箍筋锈蚀率的增加,试件的抗压强度减小;当配箍形式相同时,箍筋间距越大,箍筋锈蚀率对抗压强度的影响越显著;当箍筋间距相同时,箍筋锈蚀率对配置方形箍试件的抗压强度影响程度比配置棱形箍试件的影响大;在锈蚀箍筋试件的轴压破坏位置处,箍筋是否发生断裂与配箍形式和箍筋锈蚀率有关;所建立的锈蚀箍筋约束再生混凝土的抗压强度模型考虑了配箍形式、箍筋间距、箍筋锈蚀率等重要因素的影响,适用于各种截面,经试验验证,具有良好的计算精度和适用性。

By accelerating the uniaxial compression test of recycled concrete specimens under the constraint of corroded hoops,the influence of factors such as hoop form and hoop corrosion rate on compressive strength and failure mode was studied.Based on the ultimate strength surface and failure criteria of recycled concrete,a compressive strength model of recycled concrete with corroded hoops was established,and the effectiveness of the model was verified.The results show that as the hoop corrosion rate increases,the compressive strength of the specimen decreases.When the form of hoop is the same,the larger the spacing between hoops,the more significant the effect of hoop corrosion rate on compressive strength.When the spacing between hoops is the same,the hoop corrosion rate has a greater impact on the compressive strength of specimens with square hoops than those with prismatic hoops.At the axial compression failure location of specimens constrained by corroded hoops,whether the hoop fractures is related to the form of hoop and the hoop corrosion rate.The established compressive strength model for recycled concrete constrained by corroded hoop takes into account important factors such as hoop form,hoop spacing,and hoop corrosion rate.It is suitable for various cross-sections and was verified by experiments to have good calculation accuracy and applicability.