| On the basis of a large number of field geology investigation, the theory on engineering stratification was applied to analyze and study systemically rock mass structural surface of dam abutment, and further throw light on overall character of rock mass structure. By setting up definite structural level model and statistical model, and analyzing further numerical simulation of finite element, the action of rock mass stress and shape distortion has been recognized and apprehended in depth. Hereby, at the beginning of geology research and theory analysis, the control effect of rock mass structure to rock mass shape distortion and failure of dam abutment has been threw light on. The research progressing as follows:(l)Basic developmental character and engineering control effect of continuous macrostructure plane( I and II level) of dam abutment has been systemically studied. And this kind of structural plane took important effect to appraise rock mass distortion and failure and stability.(2)Statistical character and engineering control effect of short and intermittent structural plane(IIIA and IIIB level) of dam abutment has been systemically studied. And this kind of structural plane took important effect to appraise whether latent discrete boundary of massif could be formed and rock mass quality.(3)Ensemble character of structural planes as follows: In left dam abutment, meta basalt schistosity is main, and the structure is clockwise. Low dip angle jointing didn't develop in rock mass; In right dam abutment, rupture and jointing structural plane is main, and the structure is reversed. The structure was of obvious macroscopical slaty character. Constructional soft rock mass belt with some thickness developed.(4)Rock mass of dam abutment had very complicated distortion in right bank of Xia Luo-yu damsite. Research result indicated that on the basis of all kinds of tensional fracture, intricate deformation phenomenon is controlled by three kind of fracturing failure, such as compression-plastic flowing fracture, career-fracturing and relief-fracturing and their organic assemblage in right dam abutment.(5)Rock mass stability analysis on dam abutment of Xia Luo-yu damsite as follows: In left dam abutment, sideslip control structure has been relatively integrate, and low dip angle jointing didn't develop, so integrate sliding deformation control structure couldn't been formed in three-dimensional space and rock mass stability couldn't been influenced badly; In right dam abutment, indicate rock mass distortion was caused by the rock mass mechanics condition, such as specific rock mass structure, compression stress concentrate with high strength and especial landform and so on. But at the present, because of chronic geomorphy disintegration, altitude and ascent of bank slope have been built down and palliated. Especial rock mass mechanics condition has not been existent, so all kinds of rock mass fracturing deformation was stopped to developing and steady.Based on study above, the deformation and failure character of rock mass of dam abutment has been analyzed by 2D finite element method. And the distinct recognition on stability of rock mass has been got.
|
PDF Full Text Request