Research On Design Method Of Unbonded Prestressed Concrete

Unbonded prestressed concrete is currently widely used continuous girder structure, that technology is indispensable to engineering. It not only make the structure, good adaptability to superior performance,play the potential of materials, and has high economic benefit. Despite the continuous beam structure has tall, relatively small cross section, control section internal force significantly greater than the same specification of the characteristics of ordinary reinforced concrete continuous beam, using a certain amount of prestressed tendons, still cannot avoid bearing section of large dosage of control, lead to waste of steel, construction difficult problem. Currently widely used in plastic design method of prestressed concrete are based on the established bonded characteristic, its applicability has some limitations. Therefore, carry out unbonded prestressed concrete continuous beam structure cross section curvature ductility coefficient calculation method research, set up suitable for the structure of plastic design method, has the important practical significance.The commonly used method in this paper, the prestressed concrete structure design, selection of tension caused by secondary moment and external load bending moment design value, for the sum of the statically indeterminate structure bending moment amplitude modulation object,Application model test data and computer simulation technology, the construction of unbonded prestressed concrete flexural member cross section curvature ductility coefficient calculation function and unbonded prestressed concrete continuous beam bending moment amplitude modulation coefficient calculation model, calculation formula of equivalent plastic hinge length improved, Put forward the suitable for unbonded prestressed concrete continuous beam structure of the plastic design method. The research results on plastic design of unbonded prestressed concrete continuous beam provide strong theoretical basis and technical support...