The Study Of Reinforced Fill In Deep Foudation Excavation

Nowadays,the degree of our country's urbanization is more and more deep,with the development of urbanization,foundation engineering appears in large quantity.In order to effectively protect the environment around the construction site and avoid the deformation of foundation pit soil,protection of foundation excavation engineering is particularly important.Most of foundation engineering is involved in a depth of filling,the emphasis and difficulty in construction are concentrated in here.How to deal with the filled soil directly effects the total cost and construction time-limit of the project.This paper introduces reinforced filling in the practical application of deep foundation supporting,combining a protection of foundation excavation engineering of Dalian.It plans to build a ten-floor building up the ground and two-floor under the ground.The depth of this foundation excavation is about 10~14m.The pipeline outside the foundation excavation is5-14 m horizontal distance away from exterior line of purposed building.During the foundation excavation,it is important to remove the effect of pipeline and ensure normal using.The depth of fill stratum is 7-10 m.Considering with these reasons,decide to use sloping,reinforced fill,steel pipe pile to save cost effectively.Testing with Lizheng software 7.0,the result shows the shear strength parameter need to improve from c=10kPa??=10°to c=20kPa??=25°.Therefore,the emphasis and difficulty is how to reinforce the fill.The specific way is using high pressure jet grouting method in the fill stratum.So that the shear strength parameter cohesion c and internal friction angle ? is strengthened.Reinforced pillar is used drilling rig working with high bit of rotary jet grouting to form hole and pillar.It controls the pillar effect of reinforce pillar by adjusting the cement proportion,grouting pressure,grouting speed,rate and other factors.Test the cohesion c and internal friction angel ? of reinforced fill by FDST after having reinforced.Monitor the horizontal displacement and vertical settlement of the foundation in real time during the construction and comprehensively assess the whole affection of foundation excavation.The result shows reinforcing the upper fill stratum working with other protected structure play an important role in this foundation excavation.Above all things,it is feasibility to reinforce the fill for deep foundation excavation.Based on the actual application of reinforced fill,there will be a new opinion in the complex protection of foundation excavation of future urbanization.