Research On Impact Resistance Of New-style Steel-arch Dam Under Action Of Debris Flow

Debris flow is a kind of common natural disasters in our country, which commonly occurs in the mountains or other deep valleys, steep terrain areas. It has the characteristics of suddenness and flow fast, large discharge and physical capacity and strong destructive power, etc. With the rapid development of economy, the destruction of the natural environment by human beings is becoming more and more se rious, especially the deforestation to the vegetation resources. It destroyed the vegetation growth as well as the living environment of animals and plants, and eventually landslides and other geological disasters occurred frequently, which caused serious damage to the national economy and people’s life and property. Therefore, the effectively prevention of debris flow disasters is a problem which is worthy to discussion and research deeply.Based on the debris flow disaster management of Dangc hang county red river valley, the hitting of large stone is the main reason of damaging dam especially for the gravity dam. In recent years, it has gradually become a new trend of combining steel structure and reinforcing concrete structure material applied to the cons truction debris flow dam with the rapid development of steel industry. Based on this background, in order to effectively resist large stone’s impact, considering the advantages and disadvantages of the current mudslides resisting structure, according tothe geological conditions and characteristics of debris flow of Dangchang county red basin, and combining with the characteristics of the stress of the arch dam and conventional concrete grid permeability characteristics of dam, design a new grid resisting st ructure, namely the steel arch dam concrete grid, and the simulated research of the shock resistance of the structure was determined using displays dynamic finite element analysis software ANSYS/ls-dyna, the main work includes:(1) The steel arch dam concrete grid layout of three typical parts are analyzed in numerical simulation, and analyzing the dynamic response change of the Von Mises stress, displacement, force and energy of dam stru cture at different impact part under the impact of debris flow. Results analysis shows that the integral stiffness of grid steel arch concrete dam is bigger and better coordination, as well as thecapability of resisting deformation. It has the superior shock resistance on the impact of large stone during the resistance of debris flow.(2) In order to analysis dynamic response of steel arch dam concrete grid under the impact of debris flow more comprehensively, this paper discusses the effects of the parameters of wall thickness of steel column, yield stren gth of steel, impact height of steel ball, strength grade of concrete in column tube, impact velocity of steel ball, diameter size of steel ball to the biggest impact for the steel arch dam concrete grid point and the top point displacement, maximum impact force and impact p oint of maximum stress, maximum reaction, respectively and obtained the regularity of the change in these parameters to the resista nce of the dam structure change.(3) Three typical parts of the steel arch dam concrete grid layout with support which is the same model with the third chapter as different conditions are analyzed in numerical simulation, mainly analyzing the dynamic response change of the displacement, reacting force and acceleration of dam stru cture at different impact part under the impact of debris flow, Comparing with no support dam structure, It indicate that the steel arch dam concrete grid layout with support has the superior shock resistance on the impact of large stone during the resistance of debris flow.