Abstract

The use of light steel frame and wood frame in Brazil is still recent, hence there is little information about the durability of these technologies applied in Brazilian climate conditions. The wood-based boards are used as a part of the light steel or wood frame walls and are designed to contribute to the wall structural behavior (horizontal reinforcement and resistance to suspended loads). Once the information if such boards meet the DL (design life) set in the Brazilian code of residential building performance is still unknown, this paper analyses the technical characteristics of two woodbased boards - OSB and marine plywood - aiming to gather more information concerning durability under liquid water action. Thus, tests were carried out on samples of these two boards to evaluate their behavior against liquid water and after accelerated ageing test. In all cases, OSB showed to be more sensitive to early degradation than plywood.

Abstract

Retrofit of unreinforced masonry (URM) structures is incessantly attracting interests of masonry professionals. Because there are enormous URM structure stocks in different parts of the world that have shown vulnerability to damage against out-of-plane actions due to having limited flexural strength and deformation capacity [1]. As such, there is a global trend of promoting the development of sustainable retrofit techniques for URM structures. The authors' previous study [2] has introduced the application of oriented strand board type 3 (OSB/3) as a prospective sustainable retrofit material for URM wall with evidence of improving the flexural performances. This paper presents, for the first time,experimental works on 1115 x 1115 x 215 mm double wythe single leaf URM walls. Specifically, quasi-static out-of-plane loading tests were carried out on two plain specimens, two single-sided retrofitted walls and two double-sided retrofitted walls. The flexural and displacement capacities were evaluated in both plain and retrofitted specimens, and the results substantiated that OSB/3 application improves the flexural capacity of masonry wall. Therefore, the application of OSB/3 for retrofitting URM buildings can be considered as an inexpensive, efficient and sustainable retrofit technique.

Abstract

The present study addresses the retrofitting of running-bond masonry walls through the application of oriented strand board (OSB) timber panels aiming to increase the masonry flexural strength and deformation capacity under out-of-plane actions. This paper presents the numerical analysis of masonry prisms to complement the information provided by the experimental campaign developed on flexural performances of timber retrofitted masonries. The numerical model represents the masonry components (brick and mortar) as a three-dimensional volume via volumetric finite elements, i.e. hexahedral 8-node linear brick elements with reduced integration and hourglass control. The nonlinear properties of the mortar joints and the brick units have been calibrated through information that resorts from experimental characterization tests. The numerical damage pattern and load-displacement capacity curve are compared with the experimental observations. A good agreement has been found and, therefore, the calibrated model can be employed in parametric studies, to further analyse the efficiency of the proposed timber masonry retrofit technique, and to more complex structural study cases.