Critical Points of Prefabricated Reinforced Concrete Wall Systems of Multi-storey Buildings

With respect to the dissipation of energy through plastic deformation of joints of prefabricated wall units, the paper points out the principal importance of efficient reinforcement of the prefabricated system at its joints. The method, quality and amount of reinforcement are essential for reaching the necessary degree of joint ductility. The paper presents partial results of experimental research of vertical joints of prefabricated units exposed to monotonously rising loading and repetitive shear force and formulates a conclusion that the limit state of the structure as a whole is preceded by the disintegration of joints, or that the structure tends to pass from linearly elastic behaviour to non-linearly elastic to plastic behaviour by exceeding the proportional elastic limit in joints.Experimental verification on a model of a 7-storey prefabricated structure revealed weak points in its load-bearing systems, mainly at places of critical points around openings situated in close proximity to vertical joints of mutually perpendicularly oriented walls.

Authors:

• J. Witzany
• T. Čejka
• R. Zigler

Keywords:

• dissipative energy
• dynamic and cycling load repetitive load
• working diagrams of joints

References:

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Systems", doctoral dissertation thesis, Prague, CTU
[2] Witzany, J. (1982). "Working Diagrams of Joints under Repetitive
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