Upheaval buckling of small diameter gas pipeline occurred due to strong seismic excitation during the 2007 Niigata-ken Chuetsu-Oki earthquake whose diameters were 4″ and smaller. This paper deals with investigation of the upheaval buckling of gas pipes conducted by Ministry of Economy, Trade and Industry of Japan to establish seismic design guidelines to mitigate upheaval buckling.
Sand box and field tests were conducted using small diameter pipes to simulate the upheaval buckling behaviors and construct a simple finite element model. The results clarified that the tensile properties of pipe material and pipe-soil interaction were the most effective parameters to explain the buckling behaviors.
Interaction curve of pipes can be found in the relationship between compression and bending moment in the combined loading tests. The deformation behaviors of the buried pipe tests followed the interaction curve and local buckling of buried pipes occurred in lower bending moment than that of pipes not buried.