| With the speed of industrialization and urbanization increasing, the number of production and construction projects increased gradually, such as the power transmission engineering. This kind of production and construction projects had increased by22.5%during the "Eleventh Five-Year" period as compared with the "Tenth Five-Year", and electricity demand is expected to remain8.5%annual growth rate during the "Twelfth Five-Year" period, power transmission engineering will also be increases significantly. It would produce a large number of spoil soils, debris and caused soil erosion further during the processes of tower basement excavation, the site construction and the flat of tugging and taking-up site for the stringing. It was prone to slope slide, debris drain and pollute the surrounding ecological environment because of rainfall if not taking some timely preventive measures during the development and construction stage. Therefore, the study of the prevention and control of soil erosion was imminent for the power transmission engineering.By systematic investigation, the typical case analysis and model evaluation, this paper researched the soil erosion situation of typical power transmission engineering in Jiangsu Province during the past five years, the characteristics of soil erosion in various stages of construction, in different erosion control areas and in different type areas of soil and water conservation were discussed; and it also had studied the correlation between the length of power transmission engineering and the amount of soil and water loss. By analyzing the control effect of typical power transmission engineering in Jiangsu Province, the index system was built on the base of two factors, the basic situation of erosion and the protective efficiency of soil and water conservation, the index weights was determined by using AHP and entropy weight method, and the evaluation model was constructed by using combination the weighting method; and it also made a comparative analysis of the soil and water conservation benefits for the different types of water and soil conservation areas. Finally, according to the characteristics and control effect of soil erosion, the control measures of typical power transmission engineering in Jiangsu Province were targeted proposed. The main results as follows:(1) Soil erosion characteristicsThe distribution of soil erosion is differences. The difference mainly reflected in various stages of construction and in different erosion control areas. The construction period is the strongest construction stage of soil erosion (56.79%of the total), and the tower base construction area is the strongest area of soil erosion (51.04%of the total).The erosion intensity is imbalance. The difference mainly reflected in various stages of construction, in different erosion control areas and in different type areas of soil and water conservation.The construction period is the strongest construction stage of erosion intensity, tower base construction area is the strongest area of erosion intensity, meanwhile hilly area is the strongest type areas of erosion intensity, soil erosion modulus are5630.00t/km2-a,5920.00t/km2-a,6690.90t/km2-a respectively, erosion intensity are all strong.There is a significant positive correlation between the length of power transmission engineering and the amount of soil and water loss. As for the variance of soil erosion amount over the length of power transmission engineering, the hilly area was the greatest one, the sandy plain area was the second one, and the general plains area was the last one.The greatest mean value of soil erosion amount over unit line length of power transmission engineering was the hilly area, the sandy plain area was the second one, and the general plains area was the last one, the values are19.15t/km,14.28t/kmã€12.15t/km respectively.(2) Comprehensive evaluation of soil and water conservationThere are differences in soil and water conservation benefits. The hilly area had the greatest benefits for the soil and water conservation in power transmission engineering of Jiangsu Province, followed by the general plains area, and the sandy plain area was last one. As for the fluctuation of soil and water conservation benefits, the general plains area was the greatest, the hilly area was the second one, and the sandy plain area was the last one.(3) Soil erosion control measuresErosion control measures are divided into technical countermeasures and management strategies. The technical countermeasures include the soil erosion control measures arranged and control measures in engineering design; management strategies include soil and water conservation management measures of construction units and administrative departments. |
