Experimental Study On Soil Erosion And Prediction Model Of Mountainous Highway Fill Subgrade Slope

Soil erosion has been listed as primary problems around the world, it exsists in most countries to a certain degree, including developed countries and developing countries. According to FAO experts, estimate, the amount of erosion area totals to 25 million square kilometers, accounting for 16.7 percent of the total land area. Loss of soil adds up to 26 billion tons per year. In recent years, with population growth and economic development, a sharp increase in construction and resource development activities results in a large number of excavation activities, especially for the expressway project in the mountain area, destroys the exsisting vegetation, disturbs the original soil, damages the environment seriously without effective protective measures, exacerbates the development of soil erosion.Therefore, during the highway constrction, the measures taken to protect the environment and prevent soil erosion and realize sustainable development, should be paid great attention. In recent years, a number of legislation explicitly has been introduced, aimed to composed essencial soil and water conservation reports and carry out soil and water conservation work. In a word, the research on prediction of soil erosion of mountainous expressway appears vital in particular.The soil used for the mountainous highway fill subgrade is different from the mountain original slope soil, which contains a lot of building slag stone, leading to different properties. This paper focus on the soil used for the mountainous expressway fill subgrade, conducts artificial simulation of rainfall tests, studies the process of soil erosion, analyses kinds of soil erosion factors, builds the prediction model of soil erosion. According to the the observation of hillslope runoff experimental field, the prediction model is validated.(1)Based on the exsisting artificial simulation of rainfall devices, a improved and applicable devices is designed and processed, which is used in the following test;(2)Based on artificial simulation of rainfall tests on the soil, this paper studies the process of soil erosion, including infiltration, runoff and sediment yield, on different rainfall intensities and slope gradients, builds the prediction model of soil erosion.(3)After the representative area was selected from the Liang-Zhong highway fill subgrade district, the hillslope runoff experimental field is built, according to the observation data, the prediction model is validated.(4)According to the fieldwork the Liang-Zhong highway fill subgrade district, the loss of soil erosion and soil erosion modulus are calculated and compared with other similar projects for the degree analysis of the soil erosion.