Numerical and experimental evaluation of masonry prisms by finite element method

Abstract

Numerical and experimental evaluation of masonry prisms by finite element methodAvaliação numérico-experimental de prismas de alvenaria estrutural pelo método dos elementos finitos Abstract ResumoThis work developed experimental tests and numerical models able to represent the mechanical behavior of prisms made of ordinary and high strength concrete blocks. Experimental tests of prisms were performed and a detailed micro-modeling strategy was adopted for numerical analysis. In this modeling technique, each material (block and mortar) was represented by its own mechanical properties. The validation of numerical models was based on experimental results. It was found that the obtained numerical values of compressive strength and modulus of elasticity differ by 5% from the experimentally observed values. Moreover, mechanisms responsible for the rupture of the prisms were evaluated and compared to the behaviors observed in the tests and those described in the literature. Through experimental results it is possible to conclude that the numerical models have been able to represent both the mechanical properties and the failure mechanisms.Keywords: numerical simulation, concrete prisms, prisms failure modes.No presente trabalho desenvolveram-se ensaios experimentais e modelos numéricos capazes de representar o comportamento mecânico de prismas confeccionados com blocos de concreto comuns e de alta resistência. Foram realizados ensaios experimentais de prismas e, para a análise numérica, adotou-se como estratégia de modelagem, a micromodelagem detalhada, onde cada material (bloco e argamassa) foi representado por suas propriedades mecânicas. A validação dos modelos numéricos foi realizada com base em resultados experimentais realizados. Verificou-se que os valores obtidos numericamente de resistência à compressão e módulo de elasticidade diferem 5% em relação aos valores observados experimentalmente. Ainda foram avaliados quais os mecanismos responsáveis pela ruptura dos prismas, comparando-se tanto com o comportamento verificado nos ensaios, quanto com os descritos na literatura. Por meio dos resultados experimentais conclui-se que os modelos numéricos foram capazes de representar tanto as propriedades mecânicas quanto os mecanismos responsáveis pela ruptura.Palavras-chave: simulação numérica, prismas de concreto, modos de ruptura prismas.

Analysis of deformability modulus by linear and nonlinear elastic methods in ceramic structural masonry and mortars

“…It is worth noting that in the last years several studies have been carried out regarding the compressive strength of the structural blocks, considered the main parameter for the design of this type of masonry, lacking studies about the deformation properties that these blocks present [3,4]. As an example of studies in structural masonry, we can mention: i) Santiago and Beck [5] performed quality control of several concrete structural block factories in different regions of Brazil, taking as parameters the compressive strength, dimensional analysis, and water absorption; ii) Mata et al [6] verified the flexural and shear behavior in structural masonry panels using the procedures of standards ABNT NBR 15961-1:2011 [7], EN 1996-1-1:2005 [8], and ACI TMS 530:2013 [9], not checking the other properties; iii) Fortes et al [10] studied the compressive strength of structural masonry with high strength concrete blocks; and iv) Santos et al [11] carried out modeling by the finite element method in structural masonry intending to study the compressive strength of ceramic prisms.…”

An investigation of South African low-income housing roof anchor systems

“…Fourie (2017) only focused on the material parameters of the masonry units, therefore reasonable values for the Young's Modulus, Poisson's Ratio and density of the mortar were assumed for material group "G1". The second material group (G2) consisted of hollow concrete blocks obtained from a study by Santos et al (2017). The density and the Poisson's Ratio of the masonry units and mortar were not reported by Santos et al (2017) and were therefore assumed.…”

“…The second material group (G2) consisted of hollow concrete blocks obtained from a study by Santos et al (2017). The density and the Poisson's Ratio of the masonry units and mortar were not reported by Santos et al (2017) and were therefore assumed. The parameters of the third and fourth material groups, designated as "G3" and "G4", respectively, were obtained from Agüera et al (2016) and the masonry units consist of soil-cement blocks.…”

“…For the simulation of material hardening and softening in the masonry FE model, the behaviour (stress-strain relationship) beyond the elastic range of the masonry units and mortar is required. Whilst the non-linear behaviour of the masonry units and mortar of the material groups "G1" and "G2" was not reported in their respective sources, Santos et al (2017) explained that the complete stress-strain curves for the masonry constituents of material group "G2" were determined for tension and compression from methods for estimating the stressstrain curves of plain concrete as proposed by Zhenhai (2014). These methods were used in their study to simulate testing of masonry prisms through FE modelling.…”

Performance of Roof Anchor Systems for Low-Income Housing in South Africa

“…The parameters of the first group, designated as "G1", were obtained from a study by [7] that covers an experimental investigation of the mechanical properties of masonry materials widely used to construct South African LIH and were therefore used as the benchmark material group for this study. The properties of the second group, designated as "G2", were obtained from [8], while the third and fourth group, designated as "G3" and "G4", respectively, where obtained from [9].…”