Study On Technology Of Gas Safety Control For Highway Tunnel Construction

The successful implementation of the western development strategy in China in the21st century mainly relies on the development of the highway engineering. Highway construction needs to apply tunnel technique because the western plateau in China is mountainous. Constructed underground, tunnels’constructing is a kind of concealed work. Tunnels pass through complex geologic condition which has many underlying and unpredicted geologic factors, especially the coal-bearing geologic area. The coal and the gas existence endanger the underground tunnel construction. Not handling gas properly in tunnel constructing always leads to workers’gas poisoning and suffocated, gas combustion explosion and gas outburst. Long highway tunnels have higher riskiness owing to their own disadvantages, such as the construction route is too long, the tunnel’s ventilation is difficult and so on.Combined with the monitoring technology subject about’Highway Fa’er Gas Tunnel in Liupanshui City in Guizhou province’, the general situation of Fa’er Gas Tunnel and the distribution characteristic of the coal seam were studied, and the underlying danger and risk in the course of the tunnel’s construction was analyzed in this paper, then a risk evaluation of the tunnel gas was used with the method of fuzzy overall evaluation model. On the basis of the evaluation, a comprehensive analysis on the safety construction technology was researched, such as advanced forecasting technology, real-time monitoring and outburst prevention techniques for gas and ventilation technology.The ventilation and distribution law of the gas in the tunnel were studied by analog simulation with the software of Fluent to gain the goal of safety construction. The main content and achievement of this thesis are as follows:(1) Risk factors in the highway gas tunnel construction were found, fuzzy hierarchical approach to risk analysis was introduced to assess the risk of Fa’er Gas tunnel, avoiding the subjectivity of a single evaluation method and one-sidedness; And important risk factors were identified laying the foundation for the following research.(2) Ahead forecast, forecasting mechanisms of coal and gas in the construction process of Highway gas tunnel were researched. Based on a variety of modern advanced forecasting technology, the distribution of coal seam gas in front of Fa’er Gas tunnel was forecasted and the gas content was predicted, providing useful information for the governance of seam and gas outburst.(3) Monitoring method to the tunnel gas was studied, and gas monitoring program to the Fa’er Gas tunnel was designed on the basis of project, getting the general rules of gas distribution to Fa’er Gas tunnel through the analysis of real-time gas monitoring data.(4) Dynamic simulation of gas in the tunnel was used by application of computer software, the distribution and characteristics of gas in the tunnel was also studied. Through analysis and real-time monitoring by contrast, the law of the gas flow distribution in a highway tunnel construction was obtained.(5) Valid information was integrated and extracted by a comprehensive analysis of the gas tunnel geological prospecting, geological forecasting and monitoring data; various negative factors was identified and safety control program model was established in the highway gas tunnel construction process.