Probabilistic Analysis of Plastic Collapse of Plane Frame Structure under Combined Effect of Bending Moment, Shearing Force and Axial Force

In this paper, the effect of the non-uniformity settlement of ground foundation on the upper frame structure is studied. It takes a four-story space frame structure with two spans as an example. The different pedestals are installed at the joint of column footing, which respectively form the fixed supported model and the elastic supported model. Basin shaped settlement is applied in each model. The result shows that the beams are principally suffered with the bending moment and the columns principally suffered with axial force, shear force and bending moment, and that the elastic support model has certain economy.

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Study on Numerical Simulation for Failure Process of Girder Bridge under Seismic Influence

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.530.122 ◽

2012 ◽

Vol 530 ◽

pp. 122-129

Author(s):

Hong Kai Chen ◽

Hong Mei Tang ◽

Ting Hu ◽

Yi Hu ◽

Xiao Ying He

Keyword(s):

Seismic Response ◽

Axial Force ◽

Response Spectrum ◽

Failure Process ◽

Bending Moment ◽

Shearing Force ◽

Element Analysis ◽

Seismic Force ◽

Plane Bending ◽

Girder Bridge

Based on the finite element analysis software Midas, it takes response spectrum analysis, and posts the failure mechanism and characteristics of Girder Bridge under intense earthquake. Through the seismic response spectrum displacement maps of Girder Bridge, it finds out that the abutment and foundation deformation is in evidence, especially the top of abutment foundation. Through the study of seismic internal force variation on girder and pier, it indicates that the longitudinal earthquake controls axial force, vertical shearing force and in-plane bending moment, transversal earthquake dominates transversal shearing force and out-planes bending moment. And it shows that the pier and mid-span section are seismic response sensitivity parts. The three parts, axial force, longitudinal shearing force and in-plane bending moment, becomes the controlling index of pier intensity. According to the seismic response spectrum displacement for pier and abutment, the transversal anti-seismic stiffness of pier is smaller than longitudinal one, longitudinal seismic force shows no effect on transversal displacement, and the transversal seismic force can augments longitudinal displacement. At the same condition, longitudinal seismic force changes the longitudinal distributing form of abutment and concaves it deeply, and the transversal seismic force can not change its shape, but augment its value.

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Prediction for Plastic Collapse Stresses for Pipes With Inner and Outer Circumferential Flaws

Volume 1A: Codes and Standards ◽

10.1115/pvp2018-84951 ◽

2018 ◽

Author(s):

Kunio Hasegawa ◽

Yinsheng Li ◽

Vratislav Mares ◽

Valery Lacroix

Keyword(s):

Axial Force ◽

Outer Surface ◽

Bending Moment ◽

Thick Wall ◽

Plastic Collapse ◽

Bending Stress ◽

Surface Flaws ◽

Bending Stresses

Bending stresses at incipient plastic collapse for pipes with circumferential surface flaws are predicted by net-section stress approach. Appendix C-5320 of ASME B&PV Code Section XI provides a formula of bending stress at the plastic collapse, where the formula is applicable for both inner and outer surface flaws. That is, the collapse stresses for pipes with inner and outer surface flaws are the same, because of the pipe mean radius at the flawed section being entirely the same. Authors considered the separated pipe mean radii at the flawed ligament and at the un-flawed ligament. Based on the balances of axial force and bending moment, formulas of plastic collapse stresses for each inner and outer flawed pipe were obtained. It is found that, when the flaw angle and depth are the same, the collapse stress for inner flawed pipe is slightly higher than that calculated by Appendix C-5320 formula, and the collapse stress for outer flawed pipe is slightly lower than that by Appendix C-5320 formula, as can be expected. The collapse stresses derived from the three formulas are almost the same in most instances. For less common case where the flaw angle and depth are very large for thick wall pipes, the differences amongst the three collapse stresses become large.

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