Role of shear span-to-depth ratio on shear capacity of transfer beams in high-rise buildings

摘要

Presently, Transfer structures are widely used for both low -rise and high-rise buildings, to provide flexibility in different architectural arrangements above and below the transfer structures. The various forms of transfer structures are introduced in high and low-rise buildings, examples being transfer plates and transfer girders (beams) employed for high-rise residential and commercial buildings, whilst transfer beams are commonly used in for low or medium-rise buildings. It is however well known by engineers that under heavy gravity load, concentrated stresses of high magnitude are developed, which are to be transferred through the beams. To fulfill these requirements, the depth of such a beam has to be kept much higher than the conventional beams, ranging from 1.5 m to 4.5 m. As a result, the load transfer mechanism through this beam becomes altogether different than the conventional mechanism of flexure. The experimental studies have been carried out to ascertain the range of shear span- to- depth ratio so as to achieve an efficient load transfer system with appropriate level of ductility. The present paper attempts to present the role of the shear span -to-depth -ratio in transferring heavy gravity loads through transfer beam in high rise buildings, ensuring the failure of beam in ductile mode. It has been observed that the shear span-to-depth ratio is highly influencing parameter to generate the shear capacity of transfer beams as well as its failure modes.