Zhangmu Town in Tibet of China,which lies in the southern piedmont of the median Himalayas,is a small but strategically important port of trade exchange between China and Nepal.Many rockfall events have occurred in Zh...Zhangmu Town in Tibet of China,which lies in the southern piedmont of the median Himalayas,is a small but strategically important port of trade exchange between China and Nepal.Many rockfall events have occurred in Zhangmu since 1970,resulting in huge economic losses and serious influence on the bilateral trade.We conducted a detailed field investigation on the high and steep slope in Zhangmu Town,and analyzed the distribution features,stability,failure modes and evolution of dangerous rocks of potential rockfalls.Then we numerically simulated the movement path,velocity and accumulation forms of the rockfall with PFC^(3D) program.The results indicated that the dangerous rock belt could be divided into three sections,namely,unstable section,slightly stable section and basically stable section.It was estimated that the rock debris and single dangerous rock would be unstable in the case of earthquakes or rainstorms.Due to the terrain constraints,the fallen rocks would scatter near the mouth of the Zhangmu ditch and in the Buqu River through multiple times of rolling,collision-induced diversion and bouncing.Without reinforcement,the rockfall could cause serious damage to the car parks,gas stations and National Highway 318 along the line from Zhangmu Town to Zhangmu ditch.Based on the field survey and numerical simulation,we recommended rockfall removal and interception as the major prevention measures,and protective sheds as auxiliary measure.展开更多
Put geosynthetic clay liners around underground oil-gas pipelines can reduce the potential damage to environment but it will also affect the distribution of cathodic protection current. Geosynthetic clay liners can be...Put geosynthetic clay liners around underground oil-gas pipelines can reduce the potential damage to environment but it will also affect the distribution of cathodic protection current. Geosynthetic clay liners can be regarded as anisotropic soil structure and the potential distribution on the pipeline between two adjacent cathodic protection stations was calculated based on boundary element method (BEM). The calculation results indicate that potential distribution on the pipeline with geosynthetic clay liner is lower than before. A 1500 m built pipeline with geosynthetic clay liners was selected to be calculated and to perform field test, which shows that the calculation results tally well with the field test results and the validity of the arithmetic in this paper was verified.展开更多
基金Supported by the Natural Science Foundation of Liaoning Province, China （20052193） and Ph.D. Programs Foundation of Ministry of Education o f China （20070141045）.
基金the National Key Research and Development Program(Grant No.2019YFC1509704)National Natural Science Foundation of China(Grant No.U1704243)。
文摘Zhangmu Town in Tibet of China,which lies in the southern piedmont of the median Himalayas,is a small but strategically important port of trade exchange between China and Nepal.Many rockfall events have occurred in Zhangmu since 1970,resulting in huge economic losses and serious influence on the bilateral trade.We conducted a detailed field investigation on the high and steep slope in Zhangmu Town,and analyzed the distribution features,stability,failure modes and evolution of dangerous rocks of potential rockfalls.Then we numerically simulated the movement path,velocity and accumulation forms of the rockfall with PFC^(3D) program.The results indicated that the dangerous rock belt could be divided into three sections,namely,unstable section,slightly stable section and basically stable section.It was estimated that the rock debris and single dangerous rock would be unstable in the case of earthquakes or rainstorms.Due to the terrain constraints,the fallen rocks would scatter near the mouth of the Zhangmu ditch and in the Buqu River through multiple times of rolling,collision-induced diversion and bouncing.Without reinforcement,the rockfall could cause serious damage to the car parks,gas stations and National Highway 318 along the line from Zhangmu Town to Zhangmu ditch.Based on the field survey and numerical simulation,we recommended rockfall removal and interception as the major prevention measures,and protective sheds as auxiliary measure.
文摘Put geosynthetic clay liners around underground oil-gas pipelines can reduce the potential damage to environment but it will also affect the distribution of cathodic protection current. Geosynthetic clay liners can be regarded as anisotropic soil structure and the potential distribution on the pipeline between two adjacent cathodic protection stations was calculated based on boundary element method (BEM). The calculation results indicate that potential distribution on the pipeline with geosynthetic clay liner is lower than before. A 1500 m built pipeline with geosynthetic clay liners was selected to be calculated and to perform field test, which shows that the calculation results tally well with the field test results and the validity of the arithmetic in this paper was verified.
