Dynamic Respomse Study Of Buried Gas Pipeline Under The Action Of Blasting Vibration

As a safe, economical and efficient mode of transport, buried pipeline has been widely used in gas remote transport industry. With the implementation of the process of high-speed rail, vibration generated by blasting during tunnel construction inevitably affects the ground surrounding the buried pipeline. Threat to the safe operation of buried pipelines. Once the gas pipeline has an accident (rupture, burst pipes or leaking), in addition to the direct loss of pipeline damage caused by the system itself, it may also lead to serious secondary disasters. Cause a fire or explosion, and even casualties.The tunnel which located in Xi’an to Chengdu high-speed railway buried beneath the gas pipeline. Blasting vibration generated in the tunneling construction process is likely to endanger the safe operation of underground natural gas pipeline which above the tunnel. To ensure the safe operation of the gas pipeline, and analysis the degree of effect on the buried gas pipeline caused by blasting vibration. Based on monitor blasting vibration during tunnel construction in real time, this paper using numerical simulation method to study the dynamic response of gas pipeline under the effect of blasting vibration. The main purpose is to analyze the dynamic stress distribution and its variation of buried gas pipeline in different operating conditions.Using controlled blasting vibration damping technology to reduce the effect of blasting in the tunnel construction process. In 27 on-site blasting trials, peak vibration velocity observed on the surface of buried natural gas pipeline are substantially do not exceed the safe operation of the provisions of 2cm/s, which ensure the safety of natural gas pipelines running.By analyzing the parameters of vibration generated by controlled blasting during tunnel excavation, the vibration on the surface of buried natural gas pipeline with a high frequency, attenuation fast, and short duration characteristics have been found. Most of the vibration’s frequency within a distance of 40 to 60 meters to the blasting center greater than 20Hz.And their duration is generally less than 1 second.With blasting construction of fairy rock tunnel which buried a natural gas pipeline as background, referencing the code of a gas pipeline construction, a three dimensional finite element model of buried natural gas pipeline has been created. Comparing the simulation results with the monitoring vibration data, not only the accuracy of simulation results was tested, but also the model was improved.Taking the stress of pipeline as subjects, the study of dynamic response of buried natural gas pipeline in different running conditions was carried out. The conditions includes different pressure, different friction coefficient and different diameter. The stress of buried natural gas pipeline in different conditions was calculated. The stress distribution on the pipeline, and the laws of dynamic response of buried natural gas pipeline in different conditions were found. Studies have shown that, under the action of blasting, the maximum stress of buried pipelines appears at the top. With pipeline pressure grows, the maximum stress of buried pipelines grows too. With friction coefficient grows, the maximum stress of buried pipelines grows too. With the diameter of buried pipeline grows, the maximum of buried pipelines decrease.