Study on Sensitivity of Geological Parameters of Soft Rock Dam Foundation in Wide Fault Zone
A 23 m wide fault fragmentation zone is developed at the foundation of a medium-sized reservoir gravity dam in Southwest China,and the mechanical properties of the rock body in the fragmentation zone are weak,which will have an important impact on the stability of the dam foundation during the construction,impoundment and operation of the dam.Based on the engineering geological conditions and rock me-chanical parameters,a micro-arch concrete plug replacement foundation scheme for dam foundation treatment is proposed,and three-di-mensional finite element calculations and sensitivity analyses of rock mechanical parameters of the F1 fault at the dam foundation are carried out.It is concluded that in the case of soft bedrock body with wide fracture zone,the difference of deformation modulus and the weak bearing capacity of the fault zone lead to the uneven deformation phenomenon of the dam foundation.After the replacement of the concrete plugs by micro-arch,the load carrying capacity of the dam foundation and the stress deformation of the gravity dam during the impoundment process meet the requirements.As the concrete plugs can work well,the influence of the variation of fault fracture zone parameters on the stress and deformation of the dam and dam foundation is weakened.The study provides an important reference value for the foundation treatment of grav-ity dams across wide faults.
gravity damfault zonedam foundation treatmentdeformation stabilitysensitivity analysis
万方数据
维普
