This paper presents a series of large-scale laboratory experiments conducted on pavement sections to evaluate the performance of geogrid-reinforced base layer overlying various subgrade conditions (resilient modulus ranging between 10 MPa and 72 MPa). Four types of geogrids with different tensile strengths, aperture sizes, and polymer types were used to investigate the influence of geogrids on the structural coefficients in terms of modulus improvement factor (MIF) and base layer coefficient ratios (LCRs). Further, a thorough analysis was performed on a three-layer flexible pavement system to propose firstly new models for base layer coefficients (a_2u) for control (unreinforced) sections; and secondly, LCR equations and layer coefficient models for geogrid-reinforced base layers (a_2r). The experimental results indicate that the stiffness of the subgrade significantly influences the performance of the pavement system. The optimum reinforcement depth was found to be one-third of the base layer thickness measured from the top surface. For an optimum geogrid configuration on a weak subgrade, a maximum LCR value obtained was about 1.8. As-built pavement section of Interstate Highway-8, Arizona, was evaluated to validate the proposed models. Based on the study, limiting values for MIF and LCR for geogrid-reinforced bases were proposed. Finally, a set of design charts were provided to determine the granular layer (base and subbase) thickness for a given subgrade and traffic conditions and a practical range of base layer resilient modulus values (200–400 MPa).

本文介绍了在人行道上进行的一系列大型实验室实验，以评估土工格栅加固的基层在各种路基条件（弹性模量介于10 MPa和72 MPa之间）下的性能。使用四种具有不同拉伸强度，孔径大小和聚合物类型的土工格栅，以模量改进因子（MIF）和基础层系数比（LCR s）来研究土工格栅对结构系数的影响。另外，三层柔性路面系统上进行是提出一种用于基础层系数（首先新型号的透彻分析一个_2U用于控制（未强化）部分）; 其次，LCR方程和系数层模型土工格栅增强基材层（一个_2R）。实验结果表明，路基的刚度显着影响路面系统的性能。发现最佳增强深度为从顶表面测量的基础层厚度的三分之一。对于在弱路基上的最佳土工格栅配置，获得的最大LCR值约为1.8。对亚利桑那州8号州际公路的建成人行道进行了评估，以验证所提出的模型。根据研究，MIF和LCR的极限值提出了土工格栅加筋的基础。最后，提供了一组设计图来确定给定路基和交通条件下的颗粒层（基础层和基础层）厚度以及基础层弹性模量值的实际范围（200-400 MPa）。