Study on Accuracy of CCFS Method for Calculating Seismic Response of Pipeline System Multiply Supported on Building

Abstract

Since 90s of last century, foreign scholars propose a floor response spectrum method for seismic analysis of pipeline system multiply supported on buildings, which is named as Cross-Oscillator Cross-Floor Response Spectrum (CCFS) method. The CCFS method is simple in calculation and its results are reliable. Firstly, basic assumptions in expression derivation of CCFS method are studied, such as not introducing support degrees of freedom of building, adopting displacement model and assuming white noise as earthquake excitation etc. All of these assumptions will lead to some shortcomings. Then, the defect root of CCFS method is explained by specific theoretical derivation process, and it is pointed out that utilizing CCFS method for calculating displacement of boundary degrees of freedom of pipeline system relative to building may lead to inaccuracy of results, and the white noise assumption for earthquake excitation will also certainly produce some errors. Finally, the defect of CCFS method is verified by numerical example. The conclusions can provide an important reference for reasonable application of CCFS method in seismic analysis of multiply supported pipeline system on buildings.