The nonlinear analysis of reinforced concrete rectangular slabs undermonotonic transverse loads is performed by finite element method.The layered rectangu-lar element with 4 nodes and 20 degrees of freedom is develope...The nonlinear analysis of reinforced concrete rectangular slabs undermonotonic transverse loads is performed by finite element method.The layered rectangu-lar element with 4 nodes and 20 degrees of freedom is developed,in whichbending-stretching coupling effect is taken into account.An orthotropic equivalentuniaxial stress-strain constitutive model of concrete is used.A program is worked out andused to calculate two reinforced concrete slabs.The results of calculation are in goodconformity with the corresponding test results.In addition,the influence of tension stif-fening effect of cracked concrete on the results of calculation is discussed.展开更多
Punching shear failure of flat concrete slabs is a complex phenomenon with brittle failure mode, meaning sudden structural failure and rapid decrease of load carrying capacity. Due to these reasons, the application of...Punching shear failure of flat concrete slabs is a complex phenomenon with brittle failure mode, meaning sudden structural failure and rapid decrease of load carrying capacity. Due to these reasons, the application of appropriate punching shear reinforcement in the slabs could be essential. To obtain the required structural strength and performance in slab-column junctions, the effect of the shear reinforcement type on the punching resistance must be known. For this purpose, numerous nonlinear finite element simulations were carried out to determine the behavior and punching shear strength of flat concrete slabs with different punching shear reinforcement types. The efficiency of different reinforcement types was also determined and compared. Accuracy of the numerical simulations was verified by experimental results. Based on the comparison of numerical results,?the partial factor for the design formula used in Eurocode 2 was calculated and was found to be higher than the actual one.展开更多
This paper uses the spectral stochastic finite element method(SSFEM)for analyzing reinforced concrete(RC)beam/slab problems.In doing so,it presents a new framework to study how the correlation length of a random field...This paper uses the spectral stochastic finite element method(SSFEM)for analyzing reinforced concrete(RC)beam/slab problems.In doing so,it presents a new framework to study how the correlation length of a random field(RF)with uncertain parameters will affect modeling uncertainties and reliability evaluations.It considers:1)different correlation lengths for uncertainty parameters,and 2)dead and live loads as well as the elasticity moduli of concrete and steel as a multi-dimensional RF in concrete structures.To show the SSFEM’s efficiency in the study of concrete structures and to evaluate the sensitivity of the correlation length effects in evaluating the reliability,two examples of RC beams and slabs have been investigated.According to the results,the RF correlation length is effective in modeling uncertainties and evaluating reliabilities;the longer the correlation length,the greater the dispersion range of the structure response and the higher the failure probability.展开更多
文摘The nonlinear analysis of reinforced concrete rectangular slabs undermonotonic transverse loads is performed by finite element method.The layered rectangu-lar element with 4 nodes and 20 degrees of freedom is developed,in whichbending-stretching coupling effect is taken into account.An orthotropic equivalentuniaxial stress-strain constitutive model of concrete is used.A program is worked out andused to calculate two reinforced concrete slabs.The results of calculation are in goodconformity with the corresponding test results.In addition,the influence of tension stif-fening effect of cracked concrete on the results of calculation is discussed.
文摘Punching shear failure of flat concrete slabs is a complex phenomenon with brittle failure mode, meaning sudden structural failure and rapid decrease of load carrying capacity. Due to these reasons, the application of appropriate punching shear reinforcement in the slabs could be essential. To obtain the required structural strength and performance in slab-column junctions, the effect of the shear reinforcement type on the punching resistance must be known. For this purpose, numerous nonlinear finite element simulations were carried out to determine the behavior and punching shear strength of flat concrete slabs with different punching shear reinforcement types. The efficiency of different reinforcement types was also determined and compared. Accuracy of the numerical simulations was verified by experimental results. Based on the comparison of numerical results,?the partial factor for the design formula used in Eurocode 2 was calculated and was found to be higher than the actual one.
文摘This paper uses the spectral stochastic finite element method(SSFEM)for analyzing reinforced concrete(RC)beam/slab problems.In doing so,it presents a new framework to study how the correlation length of a random field(RF)with uncertain parameters will affect modeling uncertainties and reliability evaluations.It considers:1)different correlation lengths for uncertainty parameters,and 2)dead and live loads as well as the elasticity moduli of concrete and steel as a multi-dimensional RF in concrete structures.To show the SSFEM’s efficiency in the study of concrete structures and to evaluate the sensitivity of the correlation length effects in evaluating the reliability,two examples of RC beams and slabs have been investigated.According to the results,the RF correlation length is effective in modeling uncertainties and evaluating reliabilities;the longer the correlation length,the greater the dispersion range of the structure response and the higher the failure probability.