Gao Wenhui, Lin Yuliang, Wang Xin, Zhou Tianya, Zheng Chaoxu
School of Civil Engineering, Central South University, Changsha 410075, China.
Shenzhen Municipal Group Co., Ltd., Shenzhen 518000, China.
Materials (Basel). 2023 Dec 28;17(1):164. doi: 10.3390/ma17010164.
The interface friction mechanics of reinforcement material with filler is an essential issue for the engineering design of reinforced soil structure. The interface friction mechanics is closely associated with the properties of filler and reinforcement material, which subsequently affects the overall stability. In order to investigate the interface mechanism of a double-twisted hexagonal gabion mesh with a coarse-grained filler derived from a weathered red sandstone, a large laboratory pullout test was carried out. The pullout force-displacement curve was obtained by fully mobilizing the gabion mesh to reach the peak shear stress at the interface between the gabion mesh and the coarse-grained filler. The change of force-displacement characteristics and the distribution of tensile stress in gabion mesh during the pullout process were obtained. A 3D numerical model was established based on the pullout test model, and the model for analyzing the interface characteristic between the gabion mesh and the coarse-grained filler was modeled using the FLAC3D 6.0 platform. The interface characteristics were further analyzed in terms of the displacement of soil, the displacement of reinforcement, and the shear stress of soil. The strength and deformation behaviors of the interface during the entire pullout process were well captured. The pullout force-displacement curve experiences a rapid growth stage, a development transition stage and a yielding stabilization stage. The critical displacement corresponding to peak pullout stress increases with the increase in normal stress. The normal stress determines the magnitude of shear stress at the reinforcement and soil interface, and the displacement distribution of a gabion mesh is not significantly affected by normal stress when the applied normal stress is within a range of 7-20 kPa. The findings are beneficial to engineering design and application of a gabion mesh-reinforced soil structure.
加筋材料与填料的界面摩擦力学是加筋土结构工程设计中的一个关键问题。界面摩擦力学与填料和加筋材料的特性密切相关，进而影响整体稳定性。为了研究双绞六边形石笼网与风化红砂岩粗粒填料的界面机理，进行了大型室内拉拔试验。通过充分调动石笼网使其达到石笼网与粗粒填料界面的峰值剪应力，得到了拉拔力-位移曲线。获得了拉拔过程中石笼网力-位移特性的变化及拉应力分布。基于拉拔试验模型建立了三维数值模型，并利用FLAC3D 6.0平台对石笼网与粗粒填料的界面特性分析模型进行了建模。从土体位移、加筋位移和土体剪应力方面进一步分析了界面特性。整个拉拔过程中界面的强度和变形行为得到了很好的捕捉。拉拔力-位移曲线经历快速增长阶段、发展过渡阶段和屈服稳定阶段。峰值拉拔应力对应的临界位移随法向应力的增加而增大。法向应力决定了加筋与土体界面的剪应力大小，当施加的法向应力在7-20 kPa范围内时，石笼网的位移分布受法向应力的影响不显著。研究结果对石笼网加筋土结构的工程设计与应用具有指导意义。
