Study On The Design Ground Motion Parameters Zonation Of The Gas And Oil Transmission Pipeline Project

Since the year of 1999 that the great “Western Development strategy” was proposed in China, the oil and gas pipeline engineering constructions have achieved remarkable fruits. These great projects are across the west to east of China,extending to the Yangtze River delta and the southeast coastal areas. The gas and oil transmission pipelines are the vital part of the lifeline projects, which are spanned with tens or even thousands of kilometers. For determining the ground motion parameters zonation of the oil and gas pipelines, the effect of site condition should be researched specifically. In the paper, one gas pipeline project in North China is the research object. Based on the probabilistic seismic hazard analysis method and 1D soil seismic response calculation principle, the research area is zonal studied, the fit function of site coefficient Ks is determined and the statistical distribution of characteristics periods is studied. The ground motion parameters zonation map of the area along the pipeline nearby 10 km under 10% and 5% probability in 50 years are calculated. The results are comparative studied between the site coefficients ruled by the 4th and 5th generation ground motion parameters microzoning map of China. The main research contents are following:1. According to the examples of the historical earthquake disasters to the pipelines in China and foreign countries, analyzes the seismic damage factors and the main disaster types.2. According to the seismic design codes of different types of buildings, analyzes the site design ground motion parameters, which are applicable to the seismic requirement of the pipelines. And summarize the common type of site in gas-oil transmission stations, the pipeline site and pipeline crossing project.3. In this paper, the Zhongyuan-Kaifeng gas pipeline project is studied.The seismic activity records, seismogeology background and 21 borehole records in the research area are also supplied. According to Code for seismic design of buildings, the type of site is type III. Based on the probabilistic seismic hazard analysis method and 1D soil seismic response calculation principle, 6 main building sites( Zhongkai beginning station, Puyang relay station, Pu-Fan highway crossing project, Jinzhongnan railway crossing project, Pu-tai railway and Industry road crossing project and Jindi River crossing project) are studied. The seismic hazard results and site design ground motion parameters and earthquake response spectrum under 10% and 5% probability in 50 years are calculated.4. Using the linear fitting method, the function relationship of site coefficient Ks and the rock PGA under 10% and 5% probability in 50 years is determined; the statistical distribution of characteristics periods is studied. Based on the Arc GIS spatial analysis by Kriging interpolation method, the zonation map of peak ground acceleration(PGA) and characteristics periods of the research area under 10% and 5% probability in 50 years are given.5. Using three site coefficients( the linear fitting result, the suggested values by the 4th and 5th generation ground motion parameters microzoning map of China), the zonation map of PGA of the research area under 10% and 5% probability in 50 years are calculated. The comparison results show that, the actual calculation result is higher than the results by 4th and 5th generation China microzoning map. It is indicated that the site coefficients have important influence on the results of PGA zonation map. The results could provide the reference to the seismic design of oil and gas pipeline projects in the North China.