Study On Structure Designing Theory And Engineering Application Of Building Foundation Construction On The Hillside

There isn't special design theory system for the construction of large public building project on the complex geological conditions of hillside. In this paper, according to the practical engineering problems encountered in the design process, and starting from the stability of the ground, we research some problems surround the theory analysis of constructional pile foundation on the hillside, the capacity of quasi-elliptic section eccentric compressed pile in non-uniform reinforcement conditions, the predigested analytic method of pile foundation working together with the upper building structure and design research of new-style retaining wall- frame-beam pile foundation buttressed retaining wall. The cognition and production obtained in the research as following:1. In the ground stability analysis of construction on the hillside, the main force analysis include earth stress, building load effect, mechanical effect of groundwater and earthquake effect etc.. In all the forces, we can not ignore the role of building load effects. The stability analysis of hillside that is connected with the construction had its own characteristic. The paper analysis stability of hillside under the building loads and earthquake loads, it gives the simplification formula.2. The building pile foundation enduring composite load on hillside can be used both as a support structure and a foundation. In allusion to the pile foundation load, we analyze and combine the engineering characteristics of construction pile on hillside, to the introduction of two-parameter power function of the constitutional model and may consider the analytical method and the boundary conditions, we work out the construction composite pile force theoretical analytic solution on hillside. Comparison with the known experimental data and the practical application, we validate the theoretical calculation method.3. The research indicate the pile foundation on the hillside by the lateral force at the same time by the vertical force, its horizontal carrying capacity may increase 8-10%. 4. Using the basic assumptions of normal section stress calculation in rebar-concrete structure, we deduce the capacity formula of quasi-elliptic section's eccentric pile in the non-uniform reinforcement conditions. The formula is applied to the conditions of large eccentric compression in the form of random reinforcement bearing capacity calculation.5. In the bearing capacity calculation of the quasi-elliptic section's eccentric compressed pile, as when the large eccentric load, concrete strength grades can increase from C25 to C30, the largest increase rate in the capacity of not more than 3%. This shows that stabilizing pile's concrete strength has little influence in large eccentric compression capacity. In practice projects, when the intensity of stabilizing pile is controlled by flexural bearing capacity, the concrete strength need not too high, in order to avoid unnecessary wastage.6. When the Vertical forces reinforcement amount is the same, the extent of the increase rate in capacity of "uniform reinforcement in partial section" is bigger than the extent of the increase rate in capacity of "uniform reinforcement in whole section", and with the increase of rate of reinforcement. Attention to the text to: Although "uniform reinforcement in partial section" is more economically reasonable than "uniform reinforcement in whole section", but for the stabilizing-caisson pile used in project, the re-bar cage is in the right direction is of great importance. We must attach great importance to this point in the construction, and that effective measures should be taken to ensure that the direction of the pile re-bar cage meet the design requirements.7. Using numerical analysis method to simplify the interaction between piles and rock to the static thrust of rock on the piles. Then analyze the upper structure and the pile foundation together, and not separate these two, this calculation is closer to the actual hillside construction. The analysis can elicit that any tiny non-uniform horizontal displacement of construction foundation will cause internal force change of the upper structure. Horizontal displacement of construction pile foundation on the hillside is a factor Pile in the upper internal force calculation can not be ignored. 8. Under the hillside construction ground conditions, rock in building foundation is complex, the space occupied by Wall and the building foundation restrict the disposal and the choice of the form of retaining walls, and the use of construction equipment is limited. That the restrictions on the spot to come up with the improved frame-beam pile foundation buttressed retaining wall in this paper can be used to solve the space restrictions.