Probabilistic numerical modeling of glued laminated timber beams — Experimental validation and insights into the potential of layup modification

Glued laminated timber (GLT) beams are engineered wood products composed of strength-graded timber boards bonded together and are widely used in structural applications. The variability of timber, as a naturally grown material, presents challenges in accurately assessing the mechanical properties of GLT beams. Therefore, it is crucial to develop and validate prediction models for estimating the mechanical properties of GLT beams to utilize the material’s full potential. The present study focuses on validating a previously developed numerical model for predicting the bending strength and stiffness of GLT beams using a new comprehensive dataset. The dataset consists of 62 GLT beams on a structural scale (approx. 5 to 6 m length) with well-known setups and a wide range of material quality, tested in four-point bending configurations. Additionally, the potential of layup modifications for enhancing the mechanical performance of GLT beams is explored. Monte Carlo simulations were performed for each GLT beam, and the results were compared with experimental datasets. The results show that the numerical model captures the mechanical behavior of GLT beams by reasonably predicting failure locations, estimating bending strength with a coefficient determination of R 2 ≈ 0 . 60 , and stiffness with R 2 ≈ 0 . 97 . Furthermore, layup modifications demonstrate the potential to enhance the mechanical properties of GLT beams, specifically showing a 10% increase in the mean value of bending strength. This research contributes to advancing predictive modeling for GLT beams and highlights the potential for optimizing layup configurations to improve structural efficiency. • Test data of 62 GLT beams with well-known setups are used for model validation. • Failure locations are predicted with suitable accuracy. • Bending strengths are predicted with reasonable accuracy ( R 2 =0.60). • Bending stiffnesses are predicted with high accuracy ( R 2 =0.97). • Layup modification has the potential to enhance the mechanical properties of beams.