基于土基反演模量一致性的刚性层设置方法

Setting Method of Rigid Layer Depth Based on Consistency of Subgrade Modulus

为了合理设置路面结构刚性层深度,提高模量反演结果的合理性,依托足尺环道试验路,利用落锤式弯沉仪(FWD),进行了路面各结构层逐层弯沉盆检测,分析了刚性层设置深度和荷载水平对逐层土基模量反演值的影响,建立了基于逐层土基反演模量一致性的刚性层深度设置模型.实例验证表明:与荷载水平相比,土基模量反演值受刚性层设置深度的影响较大;刚性层设置深度与路面等效厚度二者呈现指数相关性;与既有刚性层深度设置方法相比,该模型显著提高了土基反演模量一致性,逐层土基反演模量变异系数由12.9%以上降低为6.9%.

In order to reasonably set the rigid layer depth in pavement structure and improve the rationality of backcalculated modulus,the full-scale test track was used to measure the layer-by-layer deflection basins at each structural layer of pavement using falling weight deflectometer（FWD）,the influences of rigid layer depth and stress level on the layer-by-layer back-calculation modulus of subgrade were analyzed,and a setting method for the rigid layer depth based on the consistency of subgrade modulus was developed. The results of the case study show that,compared with the stress level,the effect of the rigid layer depth on the subgrade back-calculated modulus is significant.The relationship between the setting depth of the rigid layer and the pavement equivalent thickness is exponential.The comparison with other setting method of rigid layer depth show that the method developed in this paper can significantly improve the consistency of the layer-by-layer back-calculated modulus of subgrade and drastically reduce the coefficient of variation from more than 13% to 6.9%.