Contents lists available at ScienceDirect Journal of Constructional Steel Research journal homepage: www.elsevier.com/locate/jcsr Normalized shear strength of trapezoidal corrugated steel webs Moussa Leblouba ⁎ , Samer Barakat, Salah Altoubat, Talha M. Junaid, Mohamed Maalej Department of Civil & Environmental Engineering, College of Engineering, University of Sharjah, United Arab Emirates ARTICLE INFO Keywords: Corrugated web steel beam Buckling Analytical model Shear strength ABSTRACT Steel corrugated webs are vertical and lightweight plates responsible for carrying large in-plane loads before buckling. Three modes of shear failure are typical for these elements: local, global, and interactive shear buckling. In this paper, previously published analytical models for the estimation of the shear strength of trapezoidal corrugated webs are summarized, and a new model is developed. The proposed model takes into account the interaction between the modes of shear buckling. Twelve shear-critical corrugated web steel beams (CWSBs) were manufactured and tested to failure. The results were added to update the existing database, resulting in 125 test results, which were then used to compare the performance of developed and existing models. The new model is shown to be more accurate than previously published models for estimating the shear strength of corrugated steel webs, allowing for more economic designs. 1. Introduction Corrugated web steel beams (CWSBs) are structural members with high load carrying capacity, thanks to the corrugated web plate. The corrugation of the web is generally trapezoidal, comprising longitudinal (flat) and diagonal (inclined) folds (corrugations). These folds enhance the web's strength against shear buckling, which can reach 1.5–2 times the strength of ordinary flat webs [1]. When subjected to external vertical loads, beams and girders with corrugated webs resist shear forces through the vertical folds that support each other until buckling takes place, and resist bending moment through the longitudinal flanges due to the accordion effect [2,3]. Failure of CWSBs may occur due to either yielding of steel or shear buckling. Shear buckling can be local, global, or interactive, depending on the geometry of the corrugated web plate. Local shear buckling occurs in the longitudinal flat folds, whereas the global shear buckling involves several corruga- tions, forming a wrinkle extending diagonally and covering the entire web. The interactive shear buckling, on the other hand, involves multiple corrugations, however, with wrinkles localized in a part of the web. The slenderness of individual folds controls local shear buckling while the slenderness of the web plate controls the global shear buckling of corrugated webs [4]. Several studies dealt with the shear behavior of CWSBs, either experimentally or theoretically. Elgaaly et al. [5] conducted an experi- mental study on beams with trapezoidal corrugated webs and con- cluded that failure of beams is due to shear buckling of the web and observed local buckling in coarse corrugations while global buckling was observed in dense corrugations. In addition, the authors demon- strated that buckling stress formulas based on flat isotropic and orthotropic plates give accurate estimation of shear strength of corrugated webs for local and global buckling, respectively. However, Luo and Edlund [6] compared the results obtained using nonlinear finite element analysis and concluded that formula based on the orthotropic plate theory agreed well in only four out of the fifteen analyzed beams. Of the four beams, two had dense corrugations and two had large overall dimensions. Based on the fact that available experimental studies were con- ducted on small-scale specimens, Driver et al. [7] conducted full-scale experiments and finite element analysis to assess the shear behavior of trapezoidal corrugated web girders. The authors demonstrated that previous models based on plate buckling theories overestimate, con- siderably, the shear strength of corrugated webs, and they proposed a new model that combines both local and global buckling into a single interaction equation. Sause and Braxtan [4] collected a database of 102 tests from eight previously published studies and developed an analytical model for the estimation of normalized shear strength. Most of the test results were not compatible with the theoretical basis of their model, hence, the size of the database was reduced to include 22 test results only. Conse- quently, their model is valid only for corrugated webs fulfilling the geometric criteria they set. The comparison between their proposed model and three other models [3,7,8] against test data showed that the new model is more accurate than the previous ones. However, a more recent investigation by Leblouba et al. [9] demonstrated that the EN- http://dx.doi.org/10.1016/j.jcsr.2017.05.007 Received 8 September 2016; Received in revised form 27 April 2017; Accepted 10 May 2017 ⁎ Corresponding author. E-mail address: mleblouba@sharjah.ac.ae (M. Leblouba). Journal of Constructional Steel Research 136 (2017) 75–90 0143-974X/ © 2017 Elsevier Ltd. All rights reserved. MARK