Chen C.-F.,Hunan University |
Cheng X.-W.,Hunan University |
Cheng X.-W.,Zhongji Geotechnical Engineering Investigation and Design Institute
Yantu Lixue/Rock and Soil Mechanics | Year: 2012
Considering the multiple failure modes of anchor system such as pulling out of grouting mass from surrounding rock, the tensile failure of the pull rod and the shearing failure of interface between pull rod and grouting mass, etc., applying systematical reliability principle and limit equilibrium method, a direct solution of failure probability of anchor system of rock slope with double slide blocks is proposed based on Monte Carlo sample principle. Meanwhile, taking the time variation of shear strength indices of soft sliding surface c and φ and the erosion of anchor bars into account, a time-variation reliability model of anchor system of rock slope with double slide blocks in consideration of multiple failure modes of anchor is established. The calculation results of examples show that the time-variations of shear strength indices of soft sliding surface c, φ and the resistance between grouting body and surrounding rock have great impact on failure probability of anchor system, while erosion of anchor bars has less impact on it.
Wang H.-C.,Zhongji Geotechnical Engineering Investigation and Design Institute |
Wang B.,Sichuan Institute of Building Research |
Wang C.,University of Sichuan |
Qian J.-T.,Zhongji Geotechnical Engineering Investigation and Design Institute |
Wang D.-S.,Zhongji Geotechnical Engineering Investigation and Design Institute
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2010
A new model of composite subgrade which is composed of rigid and soft cushions between pile top and foundation is proposed to overcome the disadvantage of traditional composite subgrade with sand and gravel cushions in clay foundation. The mechanical behavior of the composite subgrade with two cushions under vertical load is similar to that of the composite pile foundation, and this new kind of subgrade helps to give full play to the bearing capacity of piles in subgrade and also reduce the settlement of foundation sharply. The soft cushion in this composite subgrade can protect plain concrete piles in subgrade under horizontal load. The design process of composite subgrade with two cushions is the same as that of the traditional composite subgrade, and the settlement of foundation can be determined by load test data and the equilibrium function between the load on subgrade and the resistance of pile and soil below.