Multiscale computational first order homogenization of thick shells for the analysis of out-of-plane loaded masonry walls

This work presents a multiscale method based on computational homogenization for the analysis of general heterogeneous thick shell structures, with special focus on periodic brick-masonry walls. The proposed method is designed for the analysis of shells whose micro-structure is heterogeneous in the in-plane directions, but initially homogeneous in the shell-thickness direction, a structural topology that can be found in single-leaf brick masonry walls. Under this assumption, this work proposes an efficient homogenization scheme where both the macro-scale and the micro-scale are described by the same shell theory. The proposed method is then applied to the analysis of out-of-plane loaded brick-masonry walls, and compared to experimental and micro-modeling results.Peer ReviewedPostprint (author's final draft

Nonlinear analysis of earthquake fault rupture interaction with historic masonry buildings

The response of historic masonry buildings to tectonic ground displacements is studied through analysis of a simple yet representative soil-foundation-masonry wall system. A nonlinear 3D finite element method is developed and employed to reproduce the strong nonlinear response of the rupturing soil, as well as the masonry structure. Following a sensitivity analysis of the effect of the exact location of the structure with respect to the emerging fault, the paper discusses several characteristic mechanisms of soil-structure interaction and evaluates the associated structural distress. The observed failure pattern and the consequent structural damage are shown to depend strongly, varying from minimal to dramatic, on the exact position of the structure relative to the fault. Alleviation of tectonic risk through foundation enhancement/improvement is investigated by considering alternative foundation systems. Results highlight the advantageous performance of rigid embedded and continuous foundations as opposed to more flexible and isolated supports indicating that foundation strengthening may provide important shielding against settlement and structural drift

Analysis of stray current induced by cathodic protection on steel-framed masonry structures

Cathodic protection (CP) has been successfully employed to protect steel-framed masonry buildings from corrosion related damage. When a CP system is installed to protect the structural members, other metallic items which are within the fabric of the structure but are not in direct electrical continuity may suffer from stray current interactions, resulting in accelerated corrosion of the discontinuous items. Therefore, these must be considered when CP systems are designed prior to installation. This paper presents both experimental and numerical studies into the risk and extent of stray current corrosion in steel-framed masonry structures when subject to impressed current cathodic protection. The objective is to allow CP systems to be optimised so that interference is minimised without compromising the technical or cost benefits of this method of corrosion control

The effect of masonry infill walls on the reinforced concrete frames behavior under lateral load

The reinforced concrete structures with masonry infill walls are widely used to construct buildings in Algeria, as in many parts of the world. According to earthquake analysis, this type of construction can undergo serious damage under seismic load. The interaction between the infill wall and the surrounding reinforced concrete structure is considered a key parameter, which could trigger damage and even collapse in self-stable frame buildings. To study the behavior of this type of structures and the wall–frame interaction, four half-scale single-storey, single-bay reinforced concrete unfilled and unfilled frames were constructed and tested under in-plane lateral load. Furthermore, the experimental results were analyzed using the Digital Image Correlation (DIC) technique giving a detailed analysis of displacement and strain fields. The wall–frame interaction was evaluated in terms of displacement field evolution and interface slip in the contact contour. The masonry infill wall demonstrated a significant influence on the in-plane lateral response of this type of structure. The analysis of the results of the experiment are discussed in this paper

Non-linear approaches to the response of brick masonry wall to lateral loading

The response of brick masonry wall subjected to lateral loading is presented in this paper. Modelling and analysis of masonry seems to be complicated due to two-component material with different properties and dimensions. Out-of-plane loading adds another issue to be solved. Therefore, it is necessary to perform a calibration to evaluate the dynamic properties of the structure. The response of the finite element model is improved by predicting the parameter by performing a non-linear structural analysis. The deformations obtained numerically were compared to that of experimental observations. The experiments were carried out in one of the experimental galleries in the limestone pit. The study deals with the response of the masonry separating walls at various thicknesses, mechanical properties or loading. This contribution compares the effect of variability of particular parameters to the response of the walls. The results could be used for explosion prevention and protection; masonry buildings are taking into account considering the danger of explosion of natural gas or other items. For favourable design or assessment of masonry wall exposed to the out-of-plane load, which involves also explosion, it is possible to calculate the structure using some finite element model.Web of Science1442827

An Experimental Study on the Effect of Water on Historic Brickwork Masonry

Architectural heritage is deeply threatened by extreme weather events due to ongoing climatic change. Since these phenomena are becoming more and more serious, their effects cannot be neglected when a reliable assessment of a historic masonry structure is required. In this paper, the phenomenon of rising damp was studied, focusing on the influence of water on the unit weight of masonry walls made from fired clay bricks and lime mortar. This study consists of a basic experimental research on the variations in the unit weight of masonry undergoing an ageing treatment, which was simulated through some cycles of capillary water absorption and temperature changes. The experimental study proves that penetrating damp causes an increase in masonry unit weight of more than 20%. This basic result is significant in the structural assessment of historic masonry buildings. Subsequent papers will analyze the interaction with strengths parameters

An analytical and experimental assessment of flexible road ironwork support structures

This paper describes work undertaken to investigate the mechanical performance of road ironwork installations in highways, concentrating on the chamber construction. The principal aim was to provide the background research which would allow improved designs to be developed to reduce the incidence of failures through improvements to the structural continuity between the installation and the surrounding pavement. In doing this, recycled polymeric construction materials (Jig Brix) were studied with a view to including them in future designs and specifications. This paper concentrates on the Finite Element (FE) analysis of traditional (masonry) and flexible road ironwork structures incorporating Jig Brix. The global and local buckling capacity of the Jig Brix elements was investigated and results compared well with laboratory measurements. FE models have also been developed for full-scale traditional (masonry) and flexible installations in a surrounding flexible (asphalt) pavement structure. Predictions of response to wheel loading were compared with full-scale laboratory measurements. Good agreement was achieved with the traditional (masonry) construction but poorer agreement for the flexible construction. Predictions from the FE model indicated that the use of flexible elements significantly reduces the tensile horizontal strain on the surface of the surrounding asphaltic material which is likely to reduce the incidence of surface cracking

Research Report on a Study of Non-Modular Masonry Construction

In 1947, the Small Homes Council made a detailed study and comparison of construction methods used in residential building. Included in this study was an analysis of three houses in wich modular brick were used in the exterior cavity-type masonry wall. No comparison has been available between the data so obtained and the time required to construct the same wall using non-modular materials. To obtain such data, the Small Homes Council, under the sponsorship of the Structural Clay Products Institute, this summer built an exact duplicate of one of the houses constructed in the 1947 study, but used a non-modular brick instead of modular. An analysis of the time-study data taken during the construction period indicat es that the masons' time can be reduced approximately 10 per cent through the use of modular materials. Furthermore, an examination of the brick-work indicates that an improvement in workmanship is possible through the use of modular materials. This improvement in workship is obtained through the regularity achieved by the use of modular materials.Structural Clay Products Institut

Numerical model to account for the influence of infill masonry on the RC structures behaviour

It is a common misconception considers that masonry infill walls in structural RC buildings can only increase the overall lateral load capacity, and, therefore, must always be considered beneficial to seismic performance. Recent earthquakes have showed numerous examples of severe damages or collapses of buildings caused by structural response modification induced by the non-structural masonry partitions. From a state-of-the-art review of the available numerical models for the representation of the infill masonry behaviour in structural response, it was proposed an upgraded model. The proposed model is inspired on the equivalent bi-diagonal compression strut model, and considers the non-linear behaviour of the infill masonry subjected to cyclic loads. The model was implemented and calibrated in a non-linear dynamic computer code, VISUALANL. In this paper, it is presented the proposed model and the results of the calibration analyses are briefly introduced and discussed

Understanding and controlling the ingress of driven rain through exposed, solid wall masonry structures

Long term performance of historic buildings can be affected by many environmental factors, some of which become more apparent as the competence of the fabric deteriorates. Many tall historic buildings suffer from water ingress when exposed to driving rain conditions, particularly church towers in the south west of England. It is important to recognise that leakage can occur not only through flaws in the roof of a building but also through significant thicknesses of solid masonry. Identification of the most appropriate intervention requires an understanding of the way in which water might enter the structure and the assessment of potential repair options. While the full work schedule used an integrated assessment involving laboratory, field and archival work to assess the repairs which might be undertaken on these solid wall structures, this paper focuses on the laboratory work done to inform the writing of a Technical Advice Note on the effects of wind driven rain and moisture movement in historic structures (English Heritage, 2012). The laboratory work showed that grouting and rendering was effective at reducing water penetration without retarding drying rates, but that use of internal plastering also had a very beneficial effect