# Shear lag (related software)

From StructuralWiki

**SHLAG**- Legacy software from 1990 to analyze shear lag in simple and continuous T, I, and Box Beams. Source code in FORTRAN and related reports can be downloaded from the earthquake engineering online archive maintained by University of California Berkeley. SHLAG: Shear Lag Analysis of Simple and Continuous T, I, and Box Beams Song, Qi-Gen Department of Civil Engineering, Southeast University, Nanjing, China, 1990, Stress distribution in wide beam flanges and the related problems of effective width or stress ratio have been studied experimentally and theoretically by harmonic analysis and by finite element analysis. Based upon some rational assumptions for the behavior of the web of the beam, a simplified shear lag analysis for the stresses in the flanges, which is convenient for a wide range of problems is implemented in SHLAG. The report discusses the convergence of the solution for peak stresses, and an improved technique is developed. Theoretically, due to the shear lag effect, the longitudinal distribution of the bending moment in a continuous beam with wide flanges is differenct from that for a prismatic beam analysed by elementary beam theory. A general procedure for determining the stress resultants in a continuous beam considering the shear lag effect is also presented. The program requires only a minimum amount of input data for the calculation of the stress distribution and the stress ratios in the flanges of these beams for a variety of loading cases.