Hybrid Procedure for Cracking and Time-Dependent Effects in Composite Frames at Service Load

Rapid prediction of moments in highrise composite frames considering cracking and time-effects

“…A hybrid analyticalnumerical procedure has therefore been adopted which takes into account the nonlinear effects of concrete cracking near interior joints and time-dependent effects of creep and shrinkage in composite frames [3]. The procedure is analytical at the elemental level and numerical at the structural level.…”

“…The time effects of creep and shrinkage in the concrete may lead to further progressive cracking and aging moment redistribution. Creep and shrinkage result in increase in elastic moments at joints [1][2][3]. The increase in moments at joints is primarily due to shrinkage, the contribution of creep being much smaller [1][2][3].…”

“…Creep and shrinkage result in increase in elastic moments at joints [1][2][3]. The increase in moments at joints is primarily due to shrinkage, the contribution of creep being much smaller [1][2][3]. However, cracking in concrete results in lesser increase in moments as the portion of the concrete undergoing creep and shrinkage reduces [4][5][6].…”

“…Type 1 methods are numerical in nature and require large computational effort [6][7][8][9] and Type 2 methods are analytical in nature and are computationally efficient but these methods do not take into account all the aspects [4][5]10]. A hybrid analytical-numerical procedure has been developed by the authors to take into account the nonlinear effects of concrete cracking and time-dependent effects of creep and shrinkage in composite frames [3]. The procedure is efficient but the computational effort may again become considerable for large composite building frames.…”

“…M e can be obtained from any of the readily available software and requires little computational effort. The training, validating, and testing data sets are generated using an analytical-numerical hybrid procedure of analysis [3]. The expressions also take into account the sagging moments developed in beams due to the substantial differential shortening of adjacent columns in high-rise frames.…”