重复荷载作用下低合金钢筋力学性能

主要通过建立低合金构件有限元模型,以割线弹性模量、荷载挠度、裂缝特征、残余变形为指标,研究重复荷载作用下低合金构件的力学性能。测试结果表明,在25、35 kN工况重复荷载作用下,随着荷载次数不断增加,低合金钢筋构件的割线弹性模量因构件中存在残余应变而不断衰减,荷载挠度由0.5 mm逐渐增大至2.0 mm。当重复荷载75万次数、重复荷载值在25～35 kN内逐渐增加时,低合金钢筋构件的裂缝逐渐增加,平均裂缝宽度由0.09 mm增加至0.23 mm并呈现整体逐渐增加、局部不稳定波动的发展趋势。

Study on Mechanical Properties of Low Alloy Steel Bars Under Repeated Loading

In this study, the mechanical properties of low-alloy components under repeated loads were studied by establishing finite element models of low-alloy components, taking secant modulus of elasticity, load deflection and crack characteristics as indicators. The test results show that the secant modulus of elasticity of low-alloy steel members decreases with the increase of loading times under the repeated loading conditions of 25 kN and 35 kN, and the load deflection increases from 0.5 mm to 2.0 mm. When the number of repeated loads is 750,000 and the value of repeated loads is gradually increased in the range of 25 kN-35 kN, the cracks of low alloy reinforced concrete members increase gradually, and the average crack width increases from 0.09 mm to 0.23 mm, showing a trend of overall increase and local instability fluctuation.