Analysis Of Strong-column-weak-beam Of Joint Bearing Property Of Slot-cutting In Monolithic Slab

"Strong column and weak beam" is the main design criteria of realize the goal ofearthquake fortification of reinforced concrete frame structure so that no collapsing in thestrong earthquake. Due to the increasing of the bearing capacity of beam, the goal couldnot realize in the practical engineering. One of the main reasons is the influence ofmonolithic slab to the capacity of frame beam. The current seismic design standard of ourcountry has been proposed to consider the role of reinforcement in floor when theflexural capacity of frame beam end is calculated.Based on the previous researches, in this paper, we design a six storey framestructure application of PKPM, analyze the capacity of beam-column joints, and use theimprovement measures of slot-cutting in monolithic slab on beam-column joints in orderto achieve the effect of reducing the slab and improve the capacity of the frame beam endbending. Due to the plastic hinge commonly occur at the bottom joints of the framestructure, this thesis focuses on the destruction of the bottom beam-column joints. Weconclude the result according to using the basic principle of the normal section bearingcapacity of concrete members. The flexural capacity of beam end can be decreased19%at most when the beam-column joints of frame structure using the method of slot-cuttingin the floor. The capacity of column end changes a little, and reaches to the designrequirement of strong column and weak beam.At the same time, this paper considers the influence of the stability of frame columnafter open angle seam in floor. According to the stability principle of the compressionmember, the frame column is idealized as the axial compression member, which hingedwith a spring on the upper of column end and then concluded the result according to therelation of spring rate and critical pressure. The critical pressure of frame column isdecreased after slot-cutting in floor. The stiffness of frame column is decreased, thecritical pressure changes very small when spring rate is controlled within limits, and theinfluence of the stability of the frame column is just a little. So it is feasible to use theimprovement measures of slot-cutting in floor in order to realize the design requirementof strong column and weak beam, which can play an important role in the practicalengineering.