体外预应力简支加固技术鲁棒性分析

Robustness analysis of reinforcement technology with external prestress and simple support

以均匀设计法、正交设计法以及PKPM结构设计软件为依据,对多高层混凝土结构的梁柱应用体外预应力简支加固技术的影响因素进行排序,对主要因素的影响规律进行分析.研究表明,从梁、柱单独来看,其主要影响因素有差异.比如,原混凝土强度等级高、由不设防到6度设防时梁加固技术的鲁棒性好,而原混凝土强度等级低、由6度设防到7度设防时柱加固技术的鲁棒性好;从梁柱综合来看,其主要的影响因素为抗震设防烈度、场地类别、设计板厚、结构纵跨数、设计混凝土强度及结构层数等6类.对6类影响因素组合后的鲁棒性进行排序,其中,Ⅰ1类场地、结构纵跨数为11、设计板厚90 mm、结构层数为10、设计混凝土强度等级C30的建筑结构从7度抗震设防提高到8度时,体外预应力简支加固技术鲁棒性最好.该研究为体外预应力简支加固技术的应用决策提供了理论依据.

Taking the uniform design method, orthogonal design method, and structure design software PKPM as a basis, the influencing factors of reinforcement technology with external prestress and simple support applied to beams and columns of multi-storey high rise concrete structure are arranged in sequence and the influence rule of main factors are analyzed. The result shows that viewing individually, the main influencing factors of the beam and column are different from each other. For instance, the robustness of reinforcement technology with external prestress and simple support applied to beams will be fine when the condition of high strength grade of original concrete is from non-fortification to 6-degree fortification, while the robustness of this reinforcement technology applied to columns will be good when the condition of low strength grade of original concrete is from 6-degree fortification to 7-degree fortification. And viewing comprehensively, the main influencing factors on beams and columns will be as follows: seismic precautionary intensity of structure, site category, designed thickness of slab, number of longitudinal span of structure, designed strength of concrete, and number of structure storey-6 categories in total. Among the ranked robustness of the combined 6 kinds of influencing factors, the robustness of reinforcement technology with following influencing factors will be the best: site category being I1, type longitudinal span number — 11, designed slab thickness — 90 mm, structure storey — 10, and seismic precautionary intensity of building structure with C30 designed concrete strength grade — 7 to 8 degree. The study will provide a theoretical basis for decision of the application of reinforcement technology with external prestress and simple support.