The Distribution Of Geotemperature Field Of Sichuan-Tibet Highway&the Method To Simulate Ground Temperature Of Tunnel Site

Heat damage is an assignable damage in the tunnel.which worsen the construction environment, reduce the efficiency of the machine and the lifespan of the material.Tectonic activity is very strongin the west of china, especially in the east edge of Tibet Plateau, which always go with volcano and plate jams.Because of this.building railways from the east to LhaSa will be caught in heat damage.In order to avoid suffering the heat damage, this text has studyed the distribution of geotemperature field of Sichuan-Tibet highwayand carried out numerical simulation on the geothermal.By studying the case of domestic and foreign high ground temperature in tunnel and the mechanism of high ground temperature, the main research results are as follow:1、By studying the case of domestic and foreign high ground temperature in tunnel, we found that only under the diction of existinggroundwater and special heat source simultaneously will heat damage appear。In this area, cover depth will not become the controlling factor of the appearance of the heat damage.2、By carrying outnumerical simulation on the geothermal with different geological profile model which has only a single variable,we found that the main influencingfactorswhich have a larger effect on ground temperature are density of terrestrial heat flow rate, geologic structure and groundwater and other factors.3、By collecting and sorting data,we found out the distribution rule of geothermal anomalous area of Sichuan-Tibet highway.4、this text has come up with a new method to simulate ground temperature.We carried out numerical simulation on geothermal of the Queershan tunnel site area with the new method, the results matched measured value.5、this text arise a series of line selection strategy and engineering measures by studying the feature of the geothermal.The purpose of the strategy and measures is avoiding suffering heat damage and alleviating the influence of the heat damage. In view of geothermal anomalous area,the main engineering measures are bypassing the area, rising the position of the line, putting the line along the valley, constructing when the hot spring is supplying and building tunnel on valley line.The main cooling measures are sprinkle water, ventilation and air conditioning.