Abstract:The oil-pipe from LANZHOU to CHONGQING was the only pipe that translates product oil to the Western areas. It supplied more than 70% product oil of SICHUAN and CHONGQING. It was an important artery to the western exploitation; therefore its running safety was especially significant. The earthquake of May 12 in WENCHUAN triggered a great many of slides and landslides to shape lots of large scale barrier lakes. The Tangjiashan Barrier Lake

located in the upper stream of Beichuan county

Mianyang of Sichuan province

is one of the largest scales of the barrier lakes. Once the dam breaks

it is not only threatening the safety of infrastructural facilities

cities

pathways

e.g.

and the residents

but also threatening the oil-pipe. To insure the safety of the oil-pipe during the sluice of Tangjiashan Barrier Lake

calculated the erosion depth of the FU river cross section under the three possible dam-break types. Based on the results

the erosion depth of groove is 6m and of beach is 4m under the 2/3 dam-break

while it’s 8m and 6m separately under the whole dam-break. Estimated the safety and then bring forward the corresponding lash-up measures so that guaranteed the safety of the pipe during the rapid flood of Tangjiashan Barrier Lake..