半刚性基层抗变形能力弱、脆性大，半刚性基层沥青路面容易受到温度、湿度变化影响而产生反射裂缝病害。针对此问题，现有研究采用级配碎石基层作为中间过渡层来预防半刚性基层反射裂缝病害，虽然级配碎石基层可以有效缓解反射裂缝开裂，但其塑性变形大、承载力不足，导致沥青路面更加容易发生车辙和沉陷。为此，本研究提出在级配碎石基层上、下方设置土工布应力吸收层，组成土工布加筋级配碎石基层Geotextile Reinforced Graded Crushed Stone（GRGCS）沥青路面结构，该结构可以提高级配碎石基层抗变形能力，增强沥青路面抗裂性能。针对GRGCS结构沥青路面抗反射裂缝性能研究，主要包含以下几个内容：

（1）基于断裂力学分析了半刚性基层反射裂缝产生与发展原理，探究了GRGCS结构抵抗荷载型反射裂缝的作用机理，采用MATDEM离散元法建立了半刚性基层沥青路面、级配碎石基层沥青路面以及不同土工布层位的GRGCS结构沥青路面模型，对比分析了荷载作用下不同路面模型的变形破坏规律。研究结果表明：GRGCS结构可以抑制反射裂缝剪切变形，改善应力应变集中，具有良好的抗裂性能。在级配碎石基层上、下方同时设置土工布的结构抗剪切变形能力最强。

（2）基于改进的车辙试验设计了一种适用于级配碎石基层的抗裂疲劳试验，制作了级配碎石围压试模，对比了不同沥青路面结构的疲劳寿命与变形情况，分析了土工布层位对抗裂性能的影响，评价了GRGCS结构沥青路面抗裂性能。研究结果表明：在级配碎石基层上方设置土工布可以延缓初始裂缝产生，在级配碎石基层下方设置土工布可以改变裂缝开裂模式，从而减少剪切位移变形，在级配碎石基层上、下方同时设置土工布的结构疲劳寿命显著提高。

（3）依托安康市普通干线公路养护大中修工程开展了GRGCS结构沥青路面足尺试验路研究，对试验路结构层进行了设计验算，设置了应力、应变监测点。根据试验路情况，结合监测结果，GRGCS结构沥青路面抗反射裂缝性能良好且性价比高，并提出了土工布应用于级配碎石基层的施工技术工艺。

Semi-rigid grass-roots level is weak in deformation resistance and brittle, and semi-rigid grass-roots asphalt pavement is susceptible to reflective cracks caused by temperature and humidity changes. In order to solve this problem, the existing research adopts graded crushed stone base as the intermediate transition layer to prevent the semi-rigid grass-roots reflective cracking disease, although graded crushed stone base can effectively alleviate the reflective crack cracking, but its plastic deformation is large, the bearing capacity is insufficient, and the asphalt pavement is likely to rutting and subsidence disease. For this reason, this paper proposes to set up a geotextile stress absorption layer above and below the graded crushed stone base to form a Geotextile Reinforced Graded Crushed Stone(GRGCS) asphalt pavement structure, which can improve the deformation-resistant capacity of the graded crushed stone base, and enhance the crack-resistant performance of the asphalt pavement. The study on the anti-reflective cracking performance of asphalt pavements with GRGCS structure mainly contains the following contents:

(1) Based on fracture mechanics, we analyzed the principle of generation and development of reflection cracks in semi-rigid base layer, investigated the mechanism of GRGCS structure to resist load-type reflection cracks, and established the asphalt pavement models of semi-rigid base layer, graded aggregate base layer, and different geotextile layers of GRGCS structure by using the MATDEM discrete element method, and analyzed the deformation and damage patterns of different pavement models under loads in contrast. The deformation and damage laws of different pavement models under load were comparatively analyzed. The results of the study show that the GRGCS structure can inhibit the shear deformation of reflection cracks, improve the stress-strain concentration, and have good anti-cracking performance. The structure with geotextile fabrics installed simultaneously above and below the graded gravel base layer has the strongest ability to resist shear deformation.

(2) Based on the improved rutting test, a cracking fatigue test was designed for graded gravel subgrade, and a graded crushed stone perimeter compression test model was made to compare the fatigue life and deformation of different asphalt pavement structures, analyze the influence of geotextile layers on cracking resistance, and evaluate the cracking resistance of GRGCS structural asphalt pavements. The results of the study show that setting geotextile above the graded crushed stone layer can delay the initial crack generation, setting geotextile below the graded crushed stone layer can change the crack cracking pattern, thus reducing the shear displacement deformation, and the structural fatigue life of the structure with geotextile set up above and below the graded crushed stone layer at the same time is significantly increased.

(3) Relying on the Ankang City general trunk highway maintenance and repair project, a GRGCS structural asphalt pavement foot test road study was carried out, the structural layer of the test road was designed and calculated, and stress and strain monitoring points were set up. According to the test road, combined with the monitoring results, GRGCS structure asphalt pavement has good anti-reflective cracking performance and high performance-price ratio, and put forward the geotextile applied in the construction technology of graded crushed stone layer.