Design of mold bag concrete protection for in-service oil pipelines in the low-lying areas

To meet the demands of economic development and water conservancy construction in a certain region of Hetao area, Inner Mongolia, a dam is constructed to form a flood-discharge reservoir area. Due to the accumulation of surface water caused by the rising of water level, one in-service oil pipeline which is located in the low-lying area near the newly constructed reservoir area is submerged under the water. In order to solve the risks of water scouring on the oil pipeline caused by the change of surface environment, this paper discussed the development status and common problems of the slope protection technique of mold bag concrete at home and abroad. After the application cases of mold bag concrete technique in the water conservancy engineering of rivers and ditches in the region where a pipeline laid were investigated, a design plan of protecting the pipeline in potential troubles by means of mold bag concrete technique was proposed based on the advantages of the slope protection technique of mold bag concrete, e.g. convenient construction, short construction cycle, erosion resistance, good integrity and low maintenance cost. That is to fill and cover the zone above the pipeline with soil to form a pipeline embankment, and then carry out the slope protection of mold bag concrete on both sides of the pipeline embankment and the construction of water flowing culvert. The characteristics and advantages of the slope protection of mold bag concrete can provide the reference for the treatment of similar potential troubles in oil and gas pipelines and the construction of river and ditch crossing engineering in the future.