STUDY OF TEST METHOD OF GEOMECHANICAL MODEL AND TEMPERATURE ANALOGOUS MODEL MATERIAL

Study of new geomechanical model material is one of key problems for physical modeling stability of high dam,which has not only theoretical significances,but also has value for engineering application. A new model material for geomechanical model test,temperature analogous material,is introduced and computing formulas of stability margin for overloading method,strength reserve method and comprehensive method are derived. It is shown from test findings that shearing strength τm as well as cohesion cm and internal friction coefficient fm of temperature analogous material will decreases as the temperature increases. By reducing mechanical index of material with increasing material temperature in model test,both strength reserve method and comprehensive method can be realized in the same model. At the same time,studies show that temperature field has influence on deformation within 6% range and on stress within range from -6% to 9%;and the lower temperature slightly changes,the less influence degree is. Such material and its new testing technique have been successfully adopted in geomechanical model test for high arch dams such as Jinping I,Dagangshan,etc. and are significantly valuable to engineering application