The Research On The Performance And Design Of Soil Nailing Bracing Technology In Deep Excavation

Along with the development of industry and city developments, the city ground space steps up more a piece, spatial development and use in underground have started suffering valuing. The quantity of excavation engineering increases increasingly. The excavation depth of pit develops from the shallow to the deep. Soil nailing construction is a new kind of construction, its application is more and more extensive because of its low price, the construction speed is quick. But domestic and international researches to soil nailing construction are not still thorough, it has the problem that fulfillment is run before in theoretical. At the base of analyzing and summarying the research results of the last, the author obtains some research results. I hope that it can provide the beneficial leading to the research and application of soil nailing structure.This author explains the structural characteristics, application scope, history and development. The author comprehensively analyzes the current failure mode of soil nailing construction structure, and put forward two-line modified failure mode. According to many engineering examples, it proofs the failure mode of the text is correct.Combining the soil nailing stalk dint measuring dataes of A-A section of a deep excavation construction in E2 District Pearl River New city, the author analysis the distribution regulation of soil nailing dint, it sets up the mechanics model of the anti- pulls out experiment of soil nailing.Currently, when designing the soil nailing structure, we still adopt traditional Coulomb soil pressure theories or Rankine soil pressure theories, it causes that the calculation result of soil pressure has bigger error margin. On the base of the two-line modified failure mode and the energy theory, the author deduces the energy active soil formulas of soil nailing construction. Using it to calculate soil pressure, the calculation result is accurate.Finally, joining together the two-line modified failure mode, energy active soil pressure calculation method and the distribution regulation ofsoil nailing stalk dint, the author puts forward the design method of energy safe coefficient.The research achievement will make a preferably direction to the research and application of the work function and design method of deep excavation soil nailing construction.