Study on seismic performance of shield tunnels under combined effect of axial force and bending moment in the longitudinal direction

Taking a 62 m CFST bridge with a curved-string truss as the research object, according to its reinforcement scheme, the spatial finite element models of the bridge before and after reinforcement were established by using the general finite element software ANSYS. The natural frequencies of the bridge before and after reinforcement were calculated, and the seismic performance of the bridge was analyzed by using the response spectrum method. The results show that the frequencies of the reinforced bridges increase in varying degrees, especially the vertical and torsional frequencies. Before and after reinforcement, the maximum axial force in the upper chord of the bridge is the largest, and the shear force and bending moment are small. The maximum internal force appears at the two ends of the upper chord. This position should be regarded as the weak link of the bridge seismic resistance. Under the same conditions, the axial force of the bridge after reinforcement is reduced by about 30% compared with that before reinforcement, and the displacement of the bridge after reinforcement is reduced in varying degrees. The reinforcement measures can improve the lateral and vertical stiffness of the bridge, especially the stiffness of the deck system.

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Influence of strain hardening on bending moment–axial force interaction

International Journal of Mechanical Sciences ◽

10.1016/j.ijmecsci.2011.12.004 ◽

2012 ◽

Vol 55 (1) ◽

pp. 65-77 ◽

Cited By ~ 5

Author(s):

H. Abbas ◽

N. Jones

Keyword(s):

Strain Hardening ◽

Axial Force ◽

Bending Moment ◽

Force Interaction

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Closed-form moment-curvature relations for reinforced concrete cross sections under bending moment and axial force

Engineering Structures ◽

10.1016/j.engstruct.2016.09.033 ◽

2016 ◽

Vol 129 ◽

pp. 67-80 ◽

Cited By ~ 2

Author(s):

Pedro Dias Simão ◽

Helena Barros ◽

Carla Costa Ferreira ◽

Tatiana Marques

Keyword(s):

Reinforced Concrete ◽

Closed Form ◽

Axial Force ◽

Cross Sections ◽

Bending Moment

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Preliminary Parametric Assessment of a Bolted Endplate Joint under Combined Axial Force and Cyclic Bending Moment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.255-260.718 ◽

2011 ◽

Vol 255-260 ◽

pp. 718-721

Author(s):

Z.Y. Wang ◽

Q.Y. Wang

Keyword(s):

Finite Element Analysis ◽

Axial Force ◽

Seismic Design ◽

Axial Load ◽

Failure Modes ◽

Bending Moment ◽

Element Analysis ◽

Cyclic Behaviour ◽

Joint Behaviour ◽

Steel Joints

Problems regarding the combined axial force and bending moment for the behaviour of semi-rigid steel joints under service loading have been recognized in recent studies. As an extended research on the cyclic behaviour of a bolted endplate joint, this study is performed relating to the contribution of column axial force on the cyclic behaviour of the joint. Using finite element analysis, the deteriorations of the joint performance have been evaluated. The preliminary parametric study of the joint is conducted with the consideration of flexibility of the column flange. The column axial force was observed to significantly influence the joint behaviour when the bending of the column flange dominates the failure modes. The reductions of moment resistance predicted by numerical analysis have been compared with codified suggestions. Comments have been made for further consideration of the influence of column axial load in seismic design of bolted endplate joints.

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A Comparative Study of Axial Force—Bending Moment Interaction Curve for Reinforced Concrete Slender Shear Wall With Enlarged Boundary Element

Lecture Notes in Civil Engineering - Proceedings of SECON'19 ◽

10.1007/978-3-030-26365-2_46 ◽

2019 ◽

pp. 497-503

Author(s):

Soumi Rajbanshi ◽

Abhishek Kumar ◽

Kaustubh Dasgupta

Keyword(s):

Reinforced Concrete ◽

Comparative Study ◽

Boundary Element ◽

Axial Force ◽

Bending Moment ◽

Shear Wall ◽

Moment Interaction

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Load Regime Diagram of a Pipe With Cyclically Plastic Bending

10th International Conference on Nuclear Engineering, Volume 1 ◽

10.1115/icone10-22100 ◽

2002 ◽

Author(s):

Yanping Yao ◽

Ming-Wan Lu

Keyword(s):

Axial Force ◽

Bending Moment ◽

Boundary Curve ◽

Plastic Behavior ◽

Cyclic Bending ◽

Elastic Plastic ◽

Linear Elastic ◽

Load Regime ◽

Reversed Cyclic ◽

Cyclic Bending Moment

The criteria of piping seismic design based on linear elastic analysis has been proved to be conservative, which is mainly because the influence of plastic deformation on piping dynamic response is neglected. In the present paper, a pipe under seismic excitation is simplified as an beam with tubular cross section subjected to steady axial force and fully reversed cyclic bending moment, and the elastic-plastic behavior of the pipe is studied. Various behavior of the pipe under different combinations of axial force and cyclic bending moment is discussed and the boundary curve equations between them are obtained. Also the load regime diagram for a pipe which is formed by the boundary curve equations in the loading plane is given, from which the elastic-plastic behavior of the pipe can be determined directly.

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A Simple Approach for Including Weld Residual Stresses in the Calculation of Pipe Circumferential Through-Wall Crack Opening Displacements

Volume 3: Design and Analysis ◽

10.1115/pvp2016-63169 ◽

2016 ◽

Author(s):

Richard Olson

Keyword(s):

Residual Stresses ◽

Axial Force ◽

Analytic Solution ◽

Crack Opening ◽

Bending Moment ◽

Generalized Solution ◽

Finite Element Analyses ◽

Opening Displacement ◽

Crack Face ◽

Basic Equations

Current methodologies for predicting the crack opening displacement (COD) of circumferentially through-wall cracked pipe do not include the effect of weld residual stresses (WRS). Even the most advanced COD prediction methodology only includes the effect of applied axial force, bending moment, and crack face pressure. For some years, it has been known that weld residual stresses do alter the COD, but there has been no convenient way to include them in a COD prediction without doing case-specific finite element analyses. This paper documents a generalized solution for including WRS effects on COD. The model uses a closed-form analytic solution to approximate the crack face rotations that the WRS would induce which, subsequently, can be added to the typical axial force-bending-crack face pressure COD solution. The methodology is described and the basic equations for the solution are presented. Following this, application to cases to evaluate the efficacy of the approach are presented which show a mixture of results ranging from amazingly good to “of questionable value” with respect to the FEA results.

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