Physical model test on working mechanisms of an anchor group system with four wood bolts in rammed earthen sites#br#
LI Jinfeng1，2，ZHANG Jingke1，2，WANG Nan1，2，ZHAO Linyi3，GUO Qinglin3
（1. College of Civil Engineering and Mechanics，Lanzhou University，Lanzhou，Gansu 730000，China；2. Key Laboratory of Mechanics on Disaster and Environment in Western China，The Ministry of Education of China，Lanzhou University，Lanzhou，Gansu 730000，China；3. National Research Center for Conservation of Ancient Wall Paintings and Earthen Sites，Dunhuang Academy，Dunhuang，Gansu 736200，China)
Abstract：A model test of a four-anchor system applied in the earthen site with a size of 2 m×2 m×0.5 m was carried out through a self-developed pull-out system，and the failure mode and load-displacement relationship were studied. Based on the three-dimensional finite difference method，the displacement and stress fields of rammed soil，the axial stress of a single bolt and the stress distribution of the anchor-slurry interface were analyzed. The results show that the load-displacement curve shows elastic first and then plastic. The crack radius of the soil around an anchor is about 26 cm，and the cracks among anchors are connected with each other. The failure mode of the four-anchor anchorage system is a typical composite cone failure. The numerical simulation test reveals that the load-displacement distributions of the three selected measuring lines of the four anchor system including diagonal L1，sideline L2 and center line L3 are all symmetric parabola. The stress area of the four-anchor anchorage system is concentrated in the middle soil layer of the sample. With increasing the load，the shear stress of the bolt- slurry interface will transfer from the top to the bottom of the bolt，and the upper interface will debond. Under the influence of the ramming construction technology，the anchor group may separate along the soil layer. The research results have high reference value for the design of the anchor group system with wood bolts in earthen sites.
李金峰1，2，张景科1，2，王 南1，2，赵林毅3，郭青林3. 夯筑土遗址木锚杆四锚系统锚固机制物理模型试验研究[J]. 岩石力学与工程学报, 2019, 38(11): 2321-2331.
LI Jinfeng1，2，ZHANG Jingke1，2，WANG Nan1，2，ZHAO Linyi3，GUO Qinglin3. Physical model test on working mechanisms of an anchor group system with four wood bolts in rammed earthen sites#br#. , 2019, 38(11): 2321-2331.
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2019, Vol. 38 
