沥青路面中双层半刚性基层的倒装效应

发布时间：2018-03-18 07:27

本文选题：道路工程　切入点：倒装结构　出处：《公路交通科技》2017年11期 　论文类型：期刊论文

【摘要】：为探讨具有2层半刚性基层的沥青路面中半刚性基层的结构组合与材料选择原则,采用BISAR3.0对常用的具有2层半刚性基层的沥青路面结构及其基层倒装后的沥青路面结构进行了荷载效应分析;并成型了由2层不同半刚性材料构成的复合梁式试件,通过进行四点弯曲强度试验和四点弯曲疲劳试验对比了这两种结构的强度和疲劳寿命。结果表明:常用结构的下半刚性层所受拉应力、拉应变大于上半刚性层,路面结构的疲劳寿命取决于下基层;通常将性能稍差的材料用于下层,而性能较好的材料用于上层的结构组合原则与结构的水平应力状态不吻合;将其倒装后,性能较好的材料承受较大的拉应力,而性能较差的材料承受较小的拉应力,特别是当下层的模量大于上层模量的3倍时,上半刚性层会处于受压状态,这样就可以充分发挥各层材料的性能,且提高整个结构的抗裂性能;结构分析和试验均表明倒装结构的承载能力和抗疲劳性能均有显著提高;在进行半刚性基层的结构组合与材料设计时,应该根据结构层的水平拉应力状态进行结构组合与材料设计。
[Abstract]:In order to discuss the structure combination and material selection principle of semi-rigid base in asphalt pavement with two-layer semi-rigid base, BISAR3.0 is used to analyze the load effect of asphalt pavement structure with two layers of semi-rigid base and the inverted asphalt pavement structure of base course, and the composite beam specimen made up of two different semi-rigid materials is formed. The strength and fatigue life of the two structures are compared by four point bending strength test and four point bending fatigue test. The results show that the tensile stress and strain of the lower half rigid layer of the common structure are greater than that of the upper half rigid layer. The fatigue life of pavement structure depends on the lower base; the material with lower performance is usually used in the lower layer, while the better material used in the upper layer does not agree with the horizontal stress state of the structure. When the modulus of the lower layer is 3 times greater than that of the upper layer, the upper half rigid layer will be under compression, while the material with better performance will bear larger tensile stress, while the material with poor performance will bear less tensile stress, especially when the modulus of the lower layer is 3 times of that of the upper layer. In this way, the properties of all layers can be brought into full play, and the crack resistance of the whole structure can be improved, and the structural analysis and tests show that the load-carrying capacity and fatigue resistance of the inverted structure are significantly improved. The structural combination and material design should be carried out according to the horizontal tensile stress state of the structure layer in the course of structural combination and material design of semi-rigid base.
【作者单位】：长沙理工大学交通运输工程学院;广州市高速公路有限公司;
【基金】：国家自然科学基金项目(50408007;50878032) 广东省交通运输厅项目(2013-02-013)
【分类号】：U416.217

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