循环荷载作用下建筑垃圾土动力性能

Dynamic Performance of Construction Waste Soil under Cyclic Loading

国家基础设施建设不断推进,大量建筑垃圾随之产生。对建筑垃圾进行资源化利用,不仅经济环保,且可缓解环境压力。通过室内大型动三轴试验,对建筑垃圾土与砂土动力性能展开研究,包括动应力-动应变、时程曲线、动弹性模量、阻尼比和液化评估分析。试验结果表明:建筑垃圾土破坏动应力约为砂土的1.3倍,即建筑垃圾土的承载能力明显高于砂土。在循环荷载作用下,砂土超静孔隙水压力大约是建筑垃圾的2.5倍,因此建筑垃圾土发生液化可能性更小。建筑垃圾土动弹性模量远高于砂土,最高是砂土的1.3倍。建筑垃圾土动力性能均高于一般砂土,建筑垃圾土具有代替砂土用作道路工程填料的潜力。

The continuous development of national infrastructure gave rise to a large amount of construction and demolition waste.The utilization of construction and demolition waste as a resource is not only economical and environmental friendly,but also relieves environmental pressure.The dynamic properties of construction and demolition waste soil and sand were examined by large-scale indoor dynamic triaxial test.The stress-strain,time history curve,dynamic elastic modulus,and damping ratio were analyzed,and liquefaction was evaluated.Test results demonstrate that the damage dynamic stress of construction and demolition waste is about 1.3 times that of sand.In other words,the bearing capacity of construction waste soil is obviously higher than that of sand.Under cyclic loading,the excess pore water pressure of sand is about 2.5 times that of construction and demolition waste soil;therefore the liquefaction of construction and demolition waste soil is less possible.The dynamic elastic modulus of construction and demolition waste soil is much higher than that of sand,reaching 1.3 times that of sand.In conclusion,construction waste soil has better performance than sand,hence has the potential to replace sand as filling material for road engineering.