The evaluation of semi-rigid base cracking condition is one of the most important elements of project-level pavement evaluation, and has been a key challenge facing pavement engineers for many years. This is because that the semi-rigid base cracking condition cannot be obtained through visual surveys unless the asphalt course is milled off, therefore the nondestructive detection and evaluation method is a better choice. This paper develops a nondestructive FWD-based evaluation model to evaluate the semi-rigid base cracking condition. It was found that the normalized base modulus (ratio between back-calculated and initial modulus) and the semi-rigid base cracking condition had good relationship on log-log scales, therefore the normalized base modulus was considered to be a reasonable indicator for the evaluation of semi-rigid base damage (cracking) condition. Based on the comparison of measured data and back-calculated modulus in freeway pavements, the evaluation criterion is established.

半刚性基层开裂条件的评估是项目级路面评估的最重要要素之一，并且多年来一直是路面工程师面临的主要挑战。这是因为除非铣削沥青层，否则无法通过目测获得半刚性基层开裂条件，因此无损检测和评估方法是更好的选择。本文开发了一种基于FWD的非破坏性评估模型来评估半刚性基层开裂状况。发现归一化基础模量（反算与初始模量之比）和半刚性基础开裂条件与对数-对数尺度有良好的关系，因此，归一化的基础模量被认为是评估半刚性基础损伤（开裂）状况的合理指标。基于高速公路路面实测数据与反算模量的比较，建立了评价标准。