Pipeline slope protection by reinforced rammed-earth construction in loess areas

When oil and gas pipelines are constructed by means of large excavation, environment and vegetation at the slope surface are damaged seriously. So the oil and gas pipelines running through loess slopes are generally subject to soil erosion at the pipeline ditch and the slope surface instability. In order to reinforce the slope surface protection of pipelines in the area of loess, the adverse effects of loess slopes were analyzed with Shaanxi trunk line and Qingyang branch line of Lanzhou-Zhengzhou-Changsha Product Oil Pipeline as the examples. It was proposed to protect slopes by means of rammed-earth construction with lime soil (lime-to-soil ratio of 3:7) and grass stem. That is to set up parapets at the slope foot, add grass stems into the rammed lime soil for the slope surface, and arrange drainage ditches at the slope top and on both sides parallel to the pipelines. Finally, performance evaluation was performed on 35 water works of reinforced rammed-earth construction at pipeline slopes in typical loess areas. It is shown that the slope protection method based on reinforced rammed-earth construction guarantees long service life and good protection effects with better feasibility, economy and safety.