The maximum bending moment resistance of plate girders

The maximum bending moment resistance of plate girders

Abspoel, R.

Civil Engineering and Geosciences

Structural Engineering

2014-09-10

In many steel structures like buildings, industrial halls and bridges, standard hot-rolled sections like IPE, HEA, HEB, HEM, HED and UNP in Europe and similar profiles in other regions of the world are used. The range of hot-rolled sections is limited and therefore fabricated plate girders are used when the requirements for stiffness, strength, stability and economy are not fulfilled. Such a plate girder is built up with steel plates for the top and bottom flange and for the web, weld-ed together to an I-shape cross section, single or double symmetric. Using this type of plate girders, a high degree of optimization of material use is possible by using different plate thicknesses and widths for the flanges and thickness and height for the web over the span of the girder adapted to the distribution of bending moments and the shear forces. Optimizations can be carried out for many aspects, but in this paper the bending moment resistance of a plate girder, given a certain weight per unit length, is the main topic for optimization. For a long time, this was not or hardly of interest in Western countries at all, especially because the costs of structures were mainly determined by labour cost and hardly by material cost. For nowadays structures life cycle costs and the environmental impact of structures become of more influence on the design, next to the increasing cost of steel by expanding demand by booming economies like China, Brazil, India and other upcoming economies. So, optimization for minimal use of materials has become highly important. Using higher steel grades, applying most material in the flanges and increasing the lever arm be-tween both flanges are the main possibilities to maximize the bending moment resistance of a plate girder under pure bending of a certain amount of steel. In many cases when using hot-rolled sec-tions the deflection is the decisive design criterion and therefore using high steel grades seems not useful. For plate girders with a very slender web the stiffness is not decisive and the strengths of the material can be better exploited, so using higher steel grades can be very useful.

http://resolver.tudelft.nl/uuid:b6f1e6d0-3c18-4244-af85-09a6c1f7c611

ECCS

978-92-9147-121-8

Eurosteel 2014: 7th European Conference on Steel and Composite Structures, Napoli, Italy, 10-12 September 2014

Institutional Repository

conference paper

(c) 2014 The Author(s)