| Increasing tensions in the urban land situation, often encountered in the existing buildings surrounding the deep excavation, and the facilities to do the supporting structure. Slope soil stress state by the state of earth pressure at rest and gradually turned to the active earth pressure state, leading to the supporting structure inside the pit displacement, horizontal displacement of the larger sphere of influence leading to pit the ground subsidence. In addition to this settlement the size of the excavation depth and scope, but also relate to the type of foundation pit, surrounded by geological conditions and the deformation size of the supporting structure. Although the excavation have been carefully designed in advance, but because of the pit there are many uncertain factors in the soil and the theory for excavation is not enough perfect, so the city started construction of the tunnel near the building ultra-deep foundation pit research is necessary. So, this paper is combined whit the National Natural Science Foundation of "Gradual Dissipation of Energy Based on Solid-fluid Interaction under A Mixture of Earth and Rock Slide Mechanism of Evolution, relying on the tunnel construction near Chongqing Nanping city building ultra-deep excavation, whit the excavation monitoring, by the use of limit analysis, basing on Nonlinear Finite Element and Random Medium Theory, settling about tunnel construction near the city building ultra-deep excavation research and safety assessment, a complete evaluation system to ensure that the tunnel construction near the building ultra-deep excavation safety and the stability of adjacent structures. Main tasks are:(1) On the base of fuzzy and neutral net, the selection model of pit-reinforcement is set up, the optimum design and selection of pit reinforcement will be realized.(2) Using Limit equilibrium analysis, stochastic medium theory and nonlinear finite element techniques for urban tunnel construction near the building ultra-deep excavation for a comprehensive study of technical and safety evaluation for Nanping station cut to provide ultra-deep excavation technical guidance and security guarantees. (3) Retaining wall for the piles, anchor piles pull the board rib bolting, gravity retaining wall supporting four kinds of support form had been gone about limit balance analysis and deformation analysis under gradually excavation disturbed. Analysis considered a variety of conditions and the surrounding complex environment. Studies have shown that the higher pit stability factor, better stability, the smaller supporting structure of the internal forces and deformation. A reasonable foundation pit form, protecting surrounding buildings during construction and after the completion of the stability and security.(4) Nanping station cut for ultra-deep pit in Anchor piles, sheet, plate bolt type three supporting rib form of dynamic simulation, and compared with the actual monitoring analysis, comparison indicates that the model accurately. Anchor pulling piles, piles board two kinds of support form in the excavation process, the supporting structure deformation, mainly in the upper part of the deformation, a small settlement around the pit, a small impact on the surrounding buildings. Rib bolting plate form in the excavation process, the supporting structure deformation, the upper bolt by force, the lower anchor force is small, a small settlement around the pit, a small impact on the surrounding buildings.(5) Combined with blasting monitor,and wavelet packet theory is applied in peak vibrating velocity,compared with numerical simulation results,and got the point peak vibrating velocity is simulated in this paper. Urban tunnel construction near the ultra-deep foundation pit support in building technology research and safety evaluation on the basis of the complexity of the surrounding environment deep foundation excavation disturbance effect under construction program construction process optimization, and ultimately to guide the construction purpose.
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