橡胶沥青应力吸收层力学与疲劳性能研究

防治反射裂缝是半刚性基层沥青路面新建或改建工程中的难题之一.橡胶沥青应力吸收层是一种较好的反射裂缝防治结构.本文设计了包含应力吸收层复合试件的剪切与疲劳试验,通过室内和现场取芯试件,研究了橡胶沥青应力吸收层及其他封层的力学和疲劳性能.聚酯玻纤布应力吸收层疲劳性能最好,但在较高橡胶沥青洒布量下,橡胶沥青与聚酯玻纤布应力吸收层疲劳性能接近;橡胶沥青应力吸收层的抗剪切变形能力最大,且其抗剪强度也比较高;橡胶沥青洒布量对橡胶沥青应力吸收层的抗剪强度、疲劳能力影响较大.当橡胶沥青洒布量在1.8～3.0kg/m2间增加时,橡胶沥青应力吸收层的抗剪强度、疲劳能力均增加,但不是线性关系增加.

Study of Mechanical and Fatigue Properties for Stress Absorbing Membrane Interlayer in Asphalt Rubber

Reflection cracks prevention of semi-rigid base asphalt pavement is one of the unsettled issues in new construction and reconstruction highway projects. Stress Absorbing Membrane Interlayer-Asphalt Rubber (SAMI-AR) is the one of excellent layer structures to prevent reflection cracks. Specimens including SAMI-AR and other three seals were designed, the shearing and fatigue tests were implemented. Mechanical and fatigue properties of SAMI-AR and the other seal coats were studied for specimens and site core samples. Results show that the fatigue property of Stress Absorbing Membrane Interlayer- Fiberglass Polyester Paving Mat (SAMI-FPPM) is the best in the four kinds of seals, and the fatigue properties of SAMI-AR and SAMI-FPPM are considerable with the high use of asphalt rubber. The shearing deformation of SAMI-AR is the best in the four kinds of seals and its shearing strength is better. The shearing strength and fatigue capability of SAMI- AR is affected greatly by the amount of asphalt rubber and increased gradually with the increment of used asphalt rubber from 1.8 kg/m2 to 3.0 kg/m2, but this relationship is not linear.