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Assuming given corrosion states this paper studies the effect of interference of corrosion pits on adjacent rebars on the probability of bending failure of a corroded reinforced concrete beam. Spatial distribution of localised corrosion along a beam is considered in the analyses. The probability of failure is estimated using Monte Carlo simulation. Uncertainties in material properties, geometry, loads, and corrosion damage are taken into account. Statistical data for the extent and location of corrosion is taken from literature and utilized in order to calibrate parameters of corresponding probability distribution functions. Results show that considering possible interference of localised corrosion has substantial influence on the estimated probability of failure. The results are compared with results from two practical methods which appeared not always to be conservative.

In this paper, a probabilistic approach for modelling the load-bearing capacity of glued laminated timber is presented. The specific characteristic of this approach is that, at first, timber boards are simulated according the natural growth characteristic of timber. Subsequent, glued laminated timber beams are virtually composed out of the simulated timber boards. Thereby, every kind of fabrication procedure, such as the length of the timber boards or the beam dimensions, can be recreated. Afterwards, a numerical model is used to estimate the load-bearing capacity, the bending stiffness and the type of failure of the simulated GLT beams. To ensure the quality of the numerical model it is validated with 24 GLT beams with a precisely-known beam setup; a wide agreement between the measured and the estimated material properties is identified. For a probabilistic investigation of different input parameters a Monte Carlo simulation is performed. The application of the presented approach is illustrated on selected examples (size effect, the quality of finger joint connections and grading criteria).

The paper presents a probabilistic model characterising tensile strength parallel to grain of Central European spruce boards without longitudinal joints. The effect of length of members on strength is considered explicitly by considering a member by a serial arrangement of weak sections triggered by major knots of knot clusters. In order to demonstrate the applicability of the proposed model the model parameters are calibrated based on the analysis of three samples of spruce of Switzerland (Mischler-Schrepfer, 2000 [25] ) and Austria (Schickhofer and Augustin, 2001 [28] ), in total 460 boards tested in full size. This model might serve as basis for studies concerning the length effect of boards relevant for solid timber structures as well as basis for judging the length effect of finger jointed construction timber and glulam, and as starting point for modelling the process of proof loading.

For the future development of a safe and efficient building infrastructure, it is of utmost importance to learn from past experience. In this paper, a scheme for the evaluation of experience gained from failures and malfunctions in timber structures is developed. It is highlighted that the main motivation to analyse structural failures is to learn from them. It is therefore stated that the description of the circumstances that led to structural failures is of highest importance. This is a somewhat different perspective compared to the structuring of information that can be found in existing studies on failed and malfunctioning structures in the literature. There, the focus is on the thorough description of the physical parameters related to the failures. The result of this paper is a proposed template for failure assessment that, in its complete extension, can be downloaded from the World Wide Web. The failure template is “ready to use”; however, it should mainly facilitate further discussions on the formulation on a broadly agreed format for how the structural engineering profession might standardise failure reporting.

Reliability analysis of structures for the purpose of code calibration or reliability verification of specific structures requires that the relevant failure modes are represented and analyzed. For structural timber, sustaining a life load, two failure cases for each failure mode have to be considered. These two cases are maximum load level exceeding load-carrying capacity and damage accumulation (caused by the load and its duration) leading to failure. The effect of both load intensity and load duration on the capacity of timber has been an area of large interest over the last decades; the effect of load duration is in general referred as duration of load (DOL) effect. Several research projects did address the DOL effect in the past and a number of different damage models, based on experimental evidence, have been formulated to describe the phenomenon. In the present paper, three different models for the representation of damage accumulation in timber are considered. The parameters of these models are calibrated by the use of test data whereas uncertainties associated with the model formulation and limited sample size are considered. The DOL effect is usually taken into account in code-based design of timber structures in terms of a modification factor k mod which is multiplied on the short-term resistance of the timber material. The scenario of a beam subject to office space life loads is analyzed and the modification factor k mod is calibrated by using the three different damage models.