Impacts Of Foundation's Uneven Settlement On The Internal Force Of Prestressed Frame Structures

The accidents of uneven settlementation are common occurrence over the years,The damage to buildings are always very serious.On the one hand,it influence normal use of the buildings functions,and on the other,the additional stress is caused by uneven settlementation of ground foundation,and even cause damage or invalidating of superstructure and bring huge potential security problems to the life and poverty of the people.As modern buildings are developing forward the direction of large span and large space,the structural systems of load-bearing adopt prestressed structure increasingly normalized situation in the field of construction engineering.But our country the study on uneven settlementation of ground fou-ndation at present,is still on the masonry structure and the common frame structure.The study on prestressed concrete frame structure is mainly in terms of its seismic performance.Therefore it is very necessary to study on influence of uneven settlementation of ground foundation in the prestressed frame structure.Based on the finite element software SAP2000,in the engineering background of a three-layer of multi-span prestressed frame structure,this paper established a simulation model of the uneven settlementation of the prestressed frame structure references to the settlement discrepancy between adjacent foundations and the relevant literature on the simulation calculation of the method of uneven settlementation of ground foundation,studied the change of the internal force redistribution of prestressed frame supperstructure after uneven settlementation of ground foundation,the main contents are as follows:1)The current status of uneven settlement and prestressed concrete frame structure at home and abroad are reviewed in this paper,at the same time introducing the development of prestressed concrete and the case of typical domestic prestressed structure engineering,and pointing out the theoretical significance and engineering application value of the study of the internal force redistribution of prestressed frame supperstructure after uneven settlementation.2)This paper discussed the damages and causes of uneven settlementation of ground foundation in the frame structure,and put forward for the prevention and treatment strategies of uneven settlementation at each stage of the life cycle cost of building.3)This paper made a further research about the finite element modeling process of prestressed frame structure under three different the method of uneven settlementation,including the solution to the finite element method;The current status of selection and application of finite element software;The assumption of the model;The settlement of frame beam with prestressing;The settlement of boundary conditions and settlementation of ground foundation about frame column and so on.4)Based on specific settlementation curve,this paper studied the internal force redistri-bution of prestressed frame supperstructure after uneven settlementation of ground foundation in the three different settlement ways,by using the finite element software SAP2000 to establish a three-layer of multi-span prestressed frame model.Meanwhile,it carried out comparative analysis on the influence of the supperstructure.