Second-order analysis and design of imperfect composite beam–columns

A robust computer procedure for the reliable design of scaffolding systems is proposed. The design of scaffolding is not detailed in design codes and considered by many researchers and engineers as intractable. The proposed method is based on the classical stability function, which performs excellently in highly nonlinear problems. The method is employed to predict the ultimate design load capacities of four tested 3-storey steel scaffolding units, and for the design of a 30 m×20 m×1.3 m 3-dimensional scaffolding system. As the approach is based on the rigorous second-order analysis allowing for the P-δ and P-Δ effects and for notional disturbance forces, no assumption of effective length is required. It is superior to the conventional second-order analysis of plotting only the bending moment diagram with allowance for P-Δ effect since it considers both P-Δ and P-δ effects such that section capacity check is adequate for strength and stability checking. The proposed method can be applied to large deflection and stability analysis and design of practical scaffolding systems in place of the conventional and unreliable effective length method which carries the disadvantages of uncertain assumption of effective length factor (L e /L).

Download Full-text

Limitation of effective length method and codified second-order analysis and design

Steel and Composite Structures ◽

10.12989/scs.2005.5.2_3.181 ◽

2005 ◽

Vol 5 (2_3) ◽

pp. 181-192 ◽

Cited By ~ 4

Author(s):

S.L. Chan ◽

Y.P. Liu ◽

Z.H. Zhou

Keyword(s):

Second Order ◽

Effective Length ◽

Analysis And Design ◽

Order Analysis ◽

Effective Length Method

Download Full-text

ADVANCED ANALYSIS OF STEEL–CONCRETE COMPOSITE BEAM-COLUMNS BY REFINED PLASTIC HINGE METHOD

International Journal of Structural Stability and Dynamics ◽

10.1142/s0219455412500460 ◽

2012 ◽

Vol 12 (06) ◽

pp. 1250046 ◽

Cited By ~ 8

Author(s):

M. FONG ◽

S. L. CHAN

Keyword(s):

Cross Section ◽

Cross Sections ◽

Composite Beam ◽

Plastic Hinge ◽

Practical Method ◽

Second Order ◽

Beam Columns ◽

Inelastic Analysis ◽

Code Performance ◽

Advanced Analysis

Based on the second-order inelastic analysis, this paper presents a practical method of design for steel–concrete composite beam-columns that satisfies code performance requirements. The concept of second-order inelastic analysis for structures is to consider both geometric and material nonlinearities and their imperfections so that the real structural behavior can be captured and the assumption for effective lengths is not required. The refined plastic hinge approach proposed herein traces the gradual material yielding and simulates full plasticity of a cross-section. The definitions of the initial and full yield surfaces (which are used to initiate the yielding and to indicate the full plastic stage) for steel–concrete composite cross-sections, based on the cross-section analysis, are presented. The proposed method is verified in examples of isolated composite columns and frames.

Download Full-text

Comparative Analysis and Design of Bridge Pier for Various Geometries Along Height Comparing the Parameters Deflection and Bending Stresses

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.39315 ◽

2021 ◽

Vol 9 (12) ◽

pp. 571-580

Author(s):

Prof. G. C. Jawalkar

Keyword(s):

Bending Moment ◽

Moment Equation ◽

Second Order ◽

Bridge Pier ◽

Column Buckling ◽

Circular Section ◽

Analysis And Design ◽

Order Analysis ◽

Bending Stresses ◽

Slender Column

Abstract: Slender member is subjected to axial load and biaxial bending moment and fails due to buckling. This buckling is caused due to slenderness effect also known as ‘P∆’ effect. This buckling gives rise to excessive bending moment occurring at a point of maximum deflection. This additional bending moment is considered in second order analysis. The objective of the research reported in this paper is to formulate bending moment equation by using beam column theory and to study the behaviour of solid circular section and hollow circular section of bridge pier. The optimization in area of cross section is done by providing a combination of solid and hollow circular section in place of a solid circular section of pier within permissible limits. A comparative study on behaviour for all three conditions is been carried out. Keywords: slender column, buckling, ‘P∆’ effect, beam-column, second order analysis, bridge pier.

Download Full-text