The Seismic Performance Of Daqing Ethylene Cracking Furnace

Ethylene as one of the most important basic raw material in petrochemical industry, once known as "food for the petrochemical industry. Ethylene production capacity, also become the sign of a country’s petrochemical industry development level. Ethylene cracking furnace is mainly used to crack raw material,and then fractionated to get ethylene. When the earthquake happened, it is worthy of our structure designers pay special attention to the destruction of cracking furnace structure.This paper uses the nonlinear static Pushover analysis principle to analysis the ethylene cracking furnace steel structure of daqing ethylene petrochemical plant, for resisting the earthquake. This paper first introduces the status of ethylene industry at home and abroad, and the thought of structure seismic performance design has been made detailed elaboration. Then the daqing ethylene project and the cracking furnace were introduced further. Deformation control was used in this paper for earthquake resistant design, and the capacity spectrum method in ATC-40was used to obtain target performance of the structure and then to analysis the cracking furnace structure. Under the given performance level I assume the target displacement of the structure, and then apply specific forms of lateral force distribution to the structure to calculate the seismic response of the structure. After the structure enters into the plastic state, I analysis the structure according to the structural plastic hinge appears number, location and order. Then discuss the rationality of structure design.We can easily draw the base shear-vertex displacement curve of the structure by analyzing the structure with pushover analysis principle. By comparing the two direction performance point of the base shear and displacement of the structure, we can easily draw the conclusion that the cracking furnace steel frame structure in this paper, the lengthways direction stiffness of the structure, significantly greater than crosswise direction stiffness. In this paper, the cracking furnace structure within the plane of the crosswise direction can very good protect against seven degrees rarely met earthquake. Lengthways direction structure to withstand the horizontal seismic force and seven degrees of structure under severe earthquake base shear some fairly. After loaded completely, the bottom of the structure was damaged most serious. Daqing area belongs to six degrees of earthquake area, considering the importance of ethylene cracking furnace for national production, living, we do the structure analysis with improving one degree for the design requirements of fortification structure analysis. Through analyzing we can draw a conclusion that the cracking furnace structure can withstand seven degrees rarely met earthquake.