含裂缝沥青路面橡胶应力吸收层的最佳参数研究

Study on Optimal Parameters of the Rubber Stress Absorbing Layer with Asphalt Cracks

目的找出不同等级交通荷载作用下沥青路面橡胶应力吸收层的最佳参数,从而提高路面的使用寿命.方法应用ABAQUS有限元软件建立含裂缝沥青路面三维力学模型,通过层底各应力和裂缝尖端应力强度因子的比较分析,确定橡胶应力吸收层的防裂效果;通过应力吸收层的模量和厚度与裂缝尖端处面层层底各应力的关系,确定最佳模量和厚度.结果在标准荷载BZZ-100作用下,橡胶应力吸收层的最佳模量建议取600 MPa,最佳厚度取2.5 cm.橡胶应力吸收层能够顺利的延缓并控制反射裂缝.在重载交通作用下,应力吸收层的最佳模量建议取800 MPa,最佳厚度取3 cm.结论路面橡胶应力吸收层可以对路面裂缝的产生起到抑制作用,应力吸收层的弹性模量及厚度直接影响路面裂缝的产生.

Using ABAQUS finite element softw are,a three-dimensional mechanical model of asphalt pavement w ith cracks w as built. The stresses in bottom layer and the stress intensity factor by crack tip w ere calculated. Comparing these stress results,elastic moduli and thicknesses of the stress absorbing layer,the optimal elastic modulus and thickness of the layer for anti-cracking w ere obtained. Results show that under the standard load of BZZ-100,the optimal modulus value is 600 M Pa and the optimal thickness is 2. 5 cm of the rubber stress absorbing layer. In this case,the rubber stress absorbing layer can be able to restrain and control the reflective cracking smoothly. Under heavy traffic,the modulus of rubber stress absorbing layer should be 800 M Pa and the thick-ness should be 3 cm. It indicates that the elastic modulus and thickness of stress absorbing layer have significant impacts on pavement cracks. The rubber stress absorbing layer plays an inhibitory role for pavement crack occurrence.