Bram Vandoren

Efficiency of seismic isolation on industrial plants - Case study of a gas tank

The research leading to these results has received funding from the European Unions Research Fund for Coal and Steel (RFCS) research programme under grant agreement n° [RFSR-CT-2013-00019].

Efficient End-Zone Detailing of Pre-tensioned Concrete Elements

Throughout the literature concerning end-zone detailing of pre-tensioned concrete elements, different methods can be identified to determine the necessary passive reinforcement to account for the tensile stresses occurring in the anchorage zone. Moreover, some of these models provide ambiguous instructions concerning the exact placing of the reinforcement. When these models are evaluated for the same element, a range of possible end-zone reinforcement lay-outs is obtained. These different reinforcement lay-outs also lead to different performances concerning the end-zone crack control. This paper presents a new strut-and-tie model (STM) for the calculation of the necessary end-zone reinforcement area. The design of the STM is based on stress field vector plots obtained from a finite element model in which both the transfer of the prestress force from the tendons to the surrounding concrete and the non-linear material behaviour of concrete is modelled in detail. A comparison of end-zone detailing, obtained from commonly used design models and from the proposed STM, is presented and the efficiency of these reinforcement lay-outs is evaluated in terms of crack control. It is concluded that the newly presented STM provides a simple method to determine the necessary amount of reinforcement area, leading to efficient end-zone crack control of pre-tensioned concrete elements.

EXPERIMENTAL AND ANALYTICAL ASSESSMENT OF RACKING RESISTANCE OF PARTIALLY ANCHORED TIMBER FRAME WALLS

The resistance to horizontal loads provided by timber constructions is determined by the racking resistance of the timber frame walls within the structure. In Eurocode 5 (EN 1995-1-1), two methods are described to assess the racking resistance of these structural elements. Method A refers to a mechanical model while method B is empirically based and therefore less attractive. When using method A, full anchorage of the leading stud is needed. Moreover, contributions of wall panels with openings are neglected in the assessment of the racking resistance. In this paper, an experimental campaign studying the racking resistance of partially anchored walls with different wall and loading configurations is presented. The study shows that window and door openings lead to a reduction of the racking resistance of the wall depending on the size of the opening. Additionally, a comparison between the experimental data and several design methods for the assessment of the racking resistance of the wall panels is made.