Development of a new test for determination of tensile strength of concrete blocks

An accurate experimental, numerical and analytical analysis of masonry structures is only possible if detailed information on the mechanical properties of masonry materials is known. In general, tensile strength of fragile brittle materials is a property difficult to measure in direct tensile tests. In this paper a new indirect tensile test method is proposed for determination of tensile strength of concrete blocks based on compression tests of blocks in the direction parallel to bed joints. Results of the proposed test are compared with direct tensile tests of small specimens cut from the concrete blocks. The compression test seems to be an alternative method of measuring the tensile strength of the units since it is easier to carry out and avoids problems like rotation of the specimen and debonding of the specimens from the plates

Experimental analysis of reinforced concrete block masonry walls subjected to in-plane cyclic loading

An innovative system for reinforced concrete masonry walls based on the combination of vertical and horizontal trussed reinforcement is proposed. The mechanical characterization of the seismic behavior of such reinforced masonry walls is based on static cyclic tests carried out on panels with appropriate geometry. The influence of the factors influencing the in-plane cyclic behavior of concrete masonry walls, such as the horizontal reinforcement, precompression, and masonry bond pattern, is discussed. The results are analyzed in terms of failure modes and force versus displacement diagrams, from which the seismic performance is assessed based on the ductility and energy capacity dissipation. The results stressed that the increase on the precompression level leads to a stiffer and more brittle lateral behavior of the masonry walls. The presence of horizontal reinforcement ensures better control and better distribution of cracking, even if only a marginal increase of lateral strength was found in the particular testing program.This work was partly supported by contract DISWALL – “Development of innovative systems for reinforced masonry walls” – COOP-CT-2005-018120 from the European Commission. The first author was supported by the Programme Alβan, the European Union Programme of High Level Scholarships for Latin America, Scholarship nº E06D100148BR