Tangshan Sanyou Group Thermal Power Plant Workshop Pit Support Engineering Design

"Tangshan Sanyou Group Thermal power plant Workshop Hole excavated for building foundation supports and protections engineering design" originates from the Tangshan Sanyou Group Thermal power plant Workshop hole excavated for building foundation supports and protections actual project.Has originally intended to construct the project located at south side the Tangshan NaPu economic development zone factory district,the structure excavation depth is 15.1m,the hole excavated for building foundation shape is the rectangle,the perimeter is 495 m,excavates floor space near 3110.9m2.According to the project actual situation and the domestic and foreign supports and protections present situation,have drawn up three kind of hole excavated for building foundation supports and protections plan initially: The stake anchor supports and protections,the earth nail adds the stake anchor union supports and protections(upside earth nail wall,lower part stake anchor),the SMW labor law supports and protections structure;Then has carried on the preliminary design and the parameter to these three kind of plans optimizes,and has carried on the project budget;Through carries on the analysis,the contrast and the proof to three kind of supports and protections plans,from the technical feasibility,the project reliability,the economical rational these three aspect overall evaluation,has designated a most superior hole excavated for building foundation supports and protections plan finally: Stake anchor supports and protections.Then has carried on the optimization design to this optimal plan,its optimization design's parameter is: Drills a hole filling pile long 22.85 m,the being buried depth is 8.5m;The arrangement angle of tilt is 22 degrees three anchor rods,three anchor rod lengths are 25 m,23m,21 m in turn,the first anchor rod non-anchor section chief is 13 m,the anchor section is 12m;The second anchor rod non-anchor section chief is 10 m,the anchor section chief is 13m;The third anchor rod non-anchor section chief is 7m,the anchor section chief is 14m;Three anchor rod perpendicular separate from ground from,but under is 3.1m,5.5m,5.5m,1.0m in turn;The horizontal spacing is 2m.Simultaneously also carries on the construction organization and the construction technique project design after optimization design's plan,as well as project quality monitor project design.The innovation of this design: The first is to use Fellenius method to determine the soil nail wall supporting one of the most dangerous slip surface and the determination of stability safety coefficients for the smallest slip crack surface,the N.Janbu method itself cannot solve,Fellenius method can quickly determine the most dangerous arc sliding surface.The second is stratified calculation method is adopted to improve the pile anchor supporting design,adopt a layered method,well finished the design of the pile anchor supporting scheme,namely,in counting to the first layer of design and stability checking,various aspects requirements after meet,and then on to the next layer of design and calculation.The third is the primary scheme for parameter optimization,and in the optimization design of supporting structure in the piles of soil depth and pile length do not modify the design,the main of pile buckling resistance is too large,the stability of the anchor rod excessive coefficient on the optimized design.After scheme comparison,determine the pile anchor bracing as after support scheme,the project and the scheme optimization design was carried out.Through optimizing design,in the case of ensure project safety,reduce the project cost,improve the economic benefit.After the optimal design project total cost is 62.33514 billion yuan.