Study On The Bioengineering Protection Technique To Urban Rock Slopes And Engineering Practice

With the increasing urban highways'development in our country, people's requirement to enviroment is increasing,too.In the regions of China south and area of western mountain and hill,some rock slopes will be come into being during the process of road construction.In order to meet people's requirement of enviroment,the objective of dealing with city-road rock slopes is not only to meet the stability of slopes,but also the demands of city's virescence and sighting and the satisfaction of people's living,and so on. Bioengineering protection have been one of crucial technicals to deal with rock slopes of urban highways.First,the research results of nation and overseas were synthesized comprehensively,while analysing the lacks of bioengineering protection techniques at present.Based on the above,the mechanism of antiseepage and antiscour and antishear of bioengineering protection were theoretically studied respectively in the paper,especially the mechanism of antishear of bioengineering protection,which including the micromodel design and the according formula deduced were studied in details.Second,the choice of grass seed and the techniques of bioengineering protection were analysed in details in the paper,in the same time,providing the bioengineering protection designs fitted for the rock slopes in Hunan province.Third,the choice of grass seed,which is a critical step for bioengineering protction,involves climate and the characteristics of soil and the types of slopes and the intention of protection.The general programs of fixed soil such as geocells and three-dimension vegetative net and external-soil spray seeding technique were discussed,pointing out that different choices of the program of fixed soil to various condition.In the end,the mechanism of reinforcement of grass root to the surface soil of slope were researched according to the result achieved from the tests such as shear strength and antitension strength and antierosion of water of grass roots.The engineering practice shows that to reinforce the rock slopes with bioengineering protection have attained to anticipated effect and bear nice economic and social effect.