It is analyzed that the impacts of vegetation type and soil moisture contenton shear strength of unsaturated soil through direct shearing tests for various vegetation types,different soil moisture contents and differe...It is analyzed that the impacts of vegetation type and soil moisture contenton shear strength of unsaturated soil through direct shearing tests for various vegetation types,different soil moisture contents and different-depth unsaturated soil. The results show that thecohesion of unsaturated soil changes greatly, and the friction angle changes a little with soilmoisture content. It is also shown that vegetation can improve shear strength of unsaturated soil,which therefore provides a basis thatvegetation can reinforce soil and protect slopes.展开更多
By making an evaluation index system and using Analytical Hierarchy Process(AHP) to determine the evaluation factor's weights, this paper builds the valuation model ofEco-environmental stability of Tibet and uses ...By making an evaluation index system and using Analytical Hierarchy Process(AHP) to determine the evaluation factor's weights, this paper builds the valuation model ofEco-environmental stability of Tibet and uses the overlay function of raster-GIS (geographicinformation systems) to make a result map and finds the distribution characteristics ofEco-environmental stability of Tibet based on the analysis of result map. The study shows that theEco-environmental stability of Tibet is almost good andthe unstable region which is only 9. 78% ofthe total area of Tibet is distributed in the middle and low reaches of Yarlung river. To protectthe Eco-environmental of the unstable area from farther degenerating, the government should pay moreattention on the Eco-environmental construction work on this area.展开更多
文摘It is analyzed that the impacts of vegetation type and soil moisture contenton shear strength of unsaturated soil through direct shearing tests for various vegetation types,different soil moisture contents and different-depth unsaturated soil. The results show that thecohesion of unsaturated soil changes greatly, and the friction angle changes a little with soilmoisture content. It is also shown that vegetation can improve shear strength of unsaturated soil,which therefore provides a basis thatvegetation can reinforce soil and protect slopes.
文摘By making an evaluation index system and using Analytical Hierarchy Process(AHP) to determine the evaluation factor's weights, this paper builds the valuation model ofEco-environmental stability of Tibet and uses the overlay function of raster-GIS (geographicinformation systems) to make a result map and finds the distribution characteristics ofEco-environmental stability of Tibet based on the analysis of result map. The study shows that theEco-environmental stability of Tibet is almost good andthe unstable region which is only 9. 78% ofthe total area of Tibet is distributed in the middle and low reaches of Yarlung river. To protectthe Eco-environmental of the unstable area from farther degenerating, the government should pay moreattention on the Eco-environmental construction work on this area.
