Research On Simulation Of Safety Monitoring To Deep Excavation Using Anchor-Pile Retaining Structure

Supported by National Nation Science Foundation"Measuring Points Selection of Structural Parameters Identification of Damage Stimulated by Environment and Its Validating System", coupled with the subsidiary item"the Study on Construction Technique of Foundation Pit Engineering of Low Environmental Damage"of"the Study on Modern Architectural Design and Key Construction Techniques"of the"Eleventh Five-year Plan"National Technological Supported Scheming Item , the study on the structural analysis extracted from the construction safety measuring information of the retaining structures of deep foundation pit is conducted. Considering the impact of the coaction of soil anchor and retaining pile together with the DIANA soil model, the constructing precession of foundation pit excavation is simulated, the deformation mechanism , the shaft displacement, pile tip displacement, shaft bending moment, anchor strain, and plastic deformation of soil body of retaining structures of deep foundation pit are studied in detail and numerically calculated, additionally, the numerical results are applied in the design of measuring procession of actual construction and the measuring scheme are emulationally analyzed as well as put forward .The followings are mainly studied in this paper:(1) The actuality of the monitoring technique for the retaining structures of deep foundation pit of the world is analyzed in detail, some key scientific problems of operation technology of construction monitoring of deep foundation pit are concluded, and the mainly studied contents are put forward.(2) Based on the computational theory of DIANA in-line soil body, the selection methods of key parameters of Finite Element Modeling for deep foundation pit and its theory basis are analyzed in detail.(3) DIANA FEM of the retaining structures of deep foundation pit is established, the force suffering and deformation for the retaining structures, the bottom heave, the surface settlement and the plastic deformation of the soil around the pit are calculated and analyzed detailedly, and the selection basis of the unsafe measuring point of the retaining construction of deep foundation pit is put forward. (4) The key problems of safe monitoring for deep foundation pit excavation in complex geological conditions are analyzed. Resorting to the DIANA analyzed results of anchor-pile retaining, according to the actual construction, the classic monitoring scheme for deep foundation pit is designed, and the judged standard for the stand or fall of the monitoring strategy is put forward.At last, the studies of this paper are summarized, and prospects are put forward for the future target and task.