Disintegration and expansion features of mudstone along a gas pipeline route in Guangxi

Swelling rocks spread in a vast range along a gas pipeline route in Guangxi, the disintegration characteristics and expansibility of the rocks lead to a series of geological disasters such as landslide, collapse, pipe ditch slump, washout of slope and exposion of pipeline that can do harm to pipeline operation safety. Through field investigation and laboratory tests, the distribution of swelling rocks along the gas pipeline and its engineering geological characteristics were checked, and the disintegration characteristics and expansibility of rocks were analyzed mainly from aspects of typical general influencing factors such as mineral composition, rock structure, initial water content, dry-wet cycle and so on. The results show that the two characteristics interact under the direct induction of water, and then affect the rock strength and structure stability. Based on analysis results and according to the pipeline engineering characteristics and local engineering experience, effective control measures were put forward, providing a reference to similar projects in the future.