The Monitoring And Numerical Simulating Of Construction In Underground Powerhouse Of Shiziping Hydropower Station

The underground powerhouse program has received immeasurable emphases in the construction of hydropower station in mountainous and hilly areas with the development of Water Resources and Hydropower Engineering work, especially the Western Development. The appearance of some high-span and complicated underground caverns is raising the difficulty in design as well as demand in security of implementation. The widely used New Austrian Tunneling Method in the current underground implementation possesses a distinctive feature in feeding back the implementation information through the monitoring program of the surrounding rock, so as to control over the surrounding rock stability and its support thus to ensure the implementation security.This text, sets in the background of Shiziping Hydropower Station in Li County of Sichuan Province, makes an initial judgment of the surrounding rock stability by relating it to the monitoring data of the underground powerhouse, and carry out a numerical simulation of the excavation support of the pressure pipeline in admit section on the basis of the analysis theory of the numerical value, analyzes the surrounding rock stability according to the monitoring data.The main targets of this essay are as follows:(1)To arrange the excavation support program of the Underground Powerhouse of Shiziping Hydropower Station, and to have a simple analysis of the emphases and difficulties of the relevant construction countermeasure during the implementation process.(2)To elaborate the Monitoring program of the Underground Powerhouse of Shiziping Hydropower Station and the implementation of the related work; to enumerate the recently 4 years'monitoring data of the typical cross section so as to make a initial analysis and judgment of the surrounding rock stability; to conclude the arch deformation of the underground cavern.(3)To elaborate the elastic-plastic constitutive of the geotechnical materials and to introduce MIDAS/GTS as well as the finite element analysis theory in the construction process. (4) To carry out a numerical simulation of the excavation support of the pressure pipeline in admit section by implying MIDAS/GTS, and to calculate the displacement of surrounding rock and other physical quantity such as bolt stress. Finally to make a judgment of the stability of the surrounding rock, and to give a guidance of the implementation of the pressure pipelines.The monitoring data and the numerical simulating calculation of Shiziping Hydropower Station demonstrates that the underground powerhouse works in good condition and the surrounding rock is in a stable situation and has sufficient safety reserve during the process of excavation support construction. which gives the guidance theory and reference data to the following implementation.