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This study aims to enhance the precision and efficiency of English Bond brick masonry by developing three unified templates: Tc, T1, and T2. These templates are designed to address the complexities in the placement of bricks, particularly queen closers and brickbats, in English Bond patterns.

The research introduces a unique numbering system integrated within each template to facilitate accurate brick placement. Template Tc is designed explicitly for corner masonry, while T1 and T2 are developed for linear masonry along the X and Y directions, respectively. The approach standardizes the bricklaying process, ensuring proper alignment and bricks overlap.

Applying these templates significantly improves the efficiency and pace of English bond brick masonry. They simplify the construction process, reduce errors, and enhance the overall quality of masonry work. The study demonstrates that using these templates results in consistent and high-quality brickwork, surpassing traditional speed, efficiency, and accuracy methods.

This study contributes a novel, systematic approach to bricklaying in English Bond masonry. The introduction of unified templates aids in skill acquisition for professionals and learners, ensuring flawless execution of masonry projects. This innovative approach holds great value in modern construction practices, promoting standardization and excellence in masonry work.

Recycled concrete is an economical and environmentally friendly green material. The shear performance of recycled concrete load-bearing masonry is studied, which is great of significance for its promotion and application and also has great significance for the sustainable development of energy materials.

In total, 30 new load-bearing block masonry samples of self-insulating recycled concrete are subjected to pure shear tests, and 42 samples are tested subjected to shear-compression composite shear tests. According to the axial design compression ratio, the test is separated into seven working conditions (0.1–0.8).

According to the test results, the recommended formula for the average shear strength along the joint section of recycled concrete block masonry is given, which can be used as a reference for engineering design. The measured shear-compression correlation curves of recycled concrete block masonry are drawn, and the proposed limits of three shear-compression failure characteristics are given. The recommended formula for the average shear strength of masonry under the theory of shear-friction with variable friction coefficient is given, providing a valuable reference for the formulation of relevant specifications and practical engineering design.

Simulated elastoplastic analysis and finite element modeling on the specimens are performed to verify the test results.

Material properties, such as shear and compressive strength of masonry, have a crucial impact on the seismic analysis results of masonry structures. Considering that most of the historical buildings are masonry structures, the damage caused by obtaining shear strengths with known methods exceeds acceptable limits. Instead of traditional shear strength index tests, this paper presents a test technique that has been developed which causes less damage to the structure, to obtain mechanical properties in masonry structures.

A new approach to shear testing and a test probe has been developed to minimize the destructive effects of mechanical in situ testing on masonry structures. The comparison of the results obtained with reduced destruction level using the novel shear strength index test probe with those obtained from the traditional method is addressed. Masonry specimens were tested in the laboratory and in situ tests were carried out on 12 historical buildings.

Test results obtained from the proposed probe shear strength index test were consistent with the results obtained from the conventional shear strength test both at the laboratory setting and in situ. Although a large number of data is needed for the validation of a method, satisfactory agreement with the conventional shear strength index test method was obtained.

The authors believe that the proposed method would give the opportunity to collect more mechanical strength data with much less destruction. The experimental work in the laboratory and in situ tests and their comparisons are the supportive and original values of this research.

The techniques available for the repair of historic masonry structures are extremely wide ranging. The advantages and disadvantages of each type of repair can be evaluated in terms of cost, time and quality as with modern projects. It is however, important to realise that when repairs to historic buildings are selected they must conform to building conservation philosophy, or an ethical and principle based evaluation. The purpose of this paper (part 2 of 2) is to establish what is meant by principles in this context and wherever possible apply practical examples to illustrate these concepts.

Evaluative literature review of the principles encapsulated within building conservation philosophy utilising them to stimulate discussion on practical repair interventions.

It has been shown that the principles of building conservation philosophy must be considered prior to making decisions relating to masonry repair. These repairs have varying degrees of defensibility, and will ultimately lead to good or bad conservation approaches. This paper briefly discusses the principles, highlighting some of the issues that may be initially confusing to the practitioner.

The evaluation of building conservation philosophy for masonry repair, and more specifically the “principles” have been little studied. The importance of this cannot however be over stated, as far from being an esoteric concept it affects every practical repair. This work brings together the study of the philosophical and practical, enabling practitioners to better understand the ramifications of building conservation philosophy for their projects. It must however be emphasised that as with any aspect of philosophy, there is not necessarily a right or wrong answer, only higher levels of defence for the selected repairs.

The infill masonry walls in recent worldwide earthquakes have shown that it is necessary to conduct further studies to characterize the behavior of existing buildings and, in particular, of infill masonry walls under seismic activity. The lack of characterization studies of infill walls made by concrete blocks justifies the investigation reported herein, which includes experimental tests on sample sets to evaluate the mechanical properties of masonry components (units and mortar) and assemblages (wallets) made with masonry units from Faial. For the later, normal compressive, diagonal tensile/shear and out-of-plane flexural strengths were obtained according to standard procedures, the results of which are presented in the manuscript. The paper aims to discuss these issues.

One experimental campaign was conducted with the aim to mechanically characterize concrete blocks masonry samples. Several experimental tests were carried out in full-scale masonry concrete wallets according to the constructive methodology used.

Based on the data obtained from the mechanical characterization tests of the concrete masonry blocks, it can be seen that under simple compression, the masonry specimens’ average resistance is about 6 times superior than the average resistance to diagonal shear/tension, while the stiffness is almost doubled. In simple compression tests, it was observed that the masonry specimens cracked in areas of higher drilling of the blocks. In the tensile tests by diagonal compression, it was found that the test specimens were mainly fissured by the block/mortar joint interfaces, following the delineation of settlement and top joints.

There are no experimental results available in the literature for this type of bricks that can contribute to the development of numerical studies.

Sustainability is well understood to encapsulate economic, environmental and societal parameters. The efficiency of maintenance interventions for historic buildings is no exception and also conforms to these broad factors. Recently, environmental considerations for masonry repair have become increasingly important and this work supports this growing area. The purpose of this paper is to give insight on how an option appraisal approach of “Green Maintenance” modelling for historic masonry buildings repair practically determine and ultimately substantiate the decision-making process using a calculation procedures of life cycle assessment, within delineated boundaries.

Calculation procedures of the model enables an assessment of embodied carbon that is expended from different stone masonry wall repair techniques and scenarios for historic masonry buildings during the maintenance phase.

It recognises the importance roles Green Maintenance model can play in reducing carbon emissions and underpins rational decision making for repair selection.

It must be emphasised that the calculation procedures presented here, is not confined to historic masonry buildings and can be applied to any repair types and building form. The decisions made as a result of the utilisation of this model practically support environmentally focused conservation decisions.

The implementation of the model highlights the efficacy of repairs that may be adopted.

The paper is a rigorous application and testing of the Green Maintenance model. The model relays the “true” carbon cost of repairs contextualised within the longevity of the materials and its embodied carbon that consequently allows rational appraisal of repair and maintenance options.

The purpose of this research is to highlight issues relating to binder migration in traditional lime mortars and the potential consequences of this phenomenon. The paper focuses on traditional mass masonry construction and will be of special interest to those surveying, maintaining and repairing historic ruinous structures and heavily exposed masonry bridges.

The paper draws on literature pertaining to the repair of traditional mass masonry structures and the somewhat limited science of binder dissolution and migration in saturated conditions. The paper also draws on the author's practical and academic knowledge of writing specifications for the repair of mass masonry structures and utilises examples of binder migration from several case study buildings.

The degree to which binder migration in traditional mortars occurs is little understood. It is, however, evident that migration of the binder occurs when saturated conditions are present and is exacerbated by prolonged moisture ingress. The effect of binder migration on the stability and performance of mass masonry structures is also little understood and requires greater attention. In addition, the nature of the repair mortars specified and the degree to which these materials have set will have a bearing on the potential for binder migration.

An assessment of binder migration in traditional lime mortars and its effect on the stability and performance of mass masonry structures has never previously been undertaken. This paper is the first to highlight the problem.

The analysis of ancient buildings presents professionals with important challenges, so it is necessary to have a rational methodology of analysis of these constructions. From the point of view of the technology of structures it is imperative to know the mechanical characteristics of the structural elements involved, as well as the existing stress levels. Currently the tendency is to obtain such knowledge in a non‐destructive way, producing minimal damage. The purpose of this paper is to provide a vision of some of the minor‐destructive techniques (MDT) applied to the diagnosis of historical rubble stone masonry structures.

The paper focuses attention on the employment of techniques based on mechanical stress aspects: flat jack, hole‐drilling and dilatometer, conducted on rubble stone masonry structures. Several computational models were made of parts of the building. These models were used to obtain experimental data (modulus of elasticity and Poisson's ratio). The accuracy of the models was contrasted through the comparison with compression stress levels obtained experimentally.

The paper provides a brief description of these MDT, and exposes the flat jack tests results obtained on several historical masonry walls in the Major Seminary of Comillas (Spain): Compression stress levels, modulus of elasticity and Poisson's ratio of several masonries of this building.

These techniques improve the computational models of constructions, because they can obtain a better knowledge of their mechanical properties, from experimental ways, and the calibration of models through experimental data.

This paper describes one of the first applications of these techniques in Spain.

The purpose of this study is to monitor the progress of construction activities in an automated way by using sensor-based technologies for tracking multiple resources that are used in building construction.

An automated on-site progress monitoring approach was proposed and a proof-of-concept prototype was developed, followed by a field experimentation study at a high-rise building construction site. The developed approach was used to integrate sensor data collected from multiple resources used in different steps of an activity. It incorporated the domain-specific heuristics that were related to the site layout conditions and method of activity.

The prototype estimated the overall progress with 95% accuracy. More accurate and up-to-date progress measurement was achieved compared to the manual approach, and the need for visual inspections and manual data collection from the field was eliminated. Overall, the field experiments demonstrated that low-cost implementation is possible, if readily available or embedded sensors on equipment are used.

Previous studies either monitored one particular piece of equipment or the developed approaches were only applicable to limited activity types. This study demonstrated that it is technically feasible to determine progress at the site by fusing sensor data that are collected from multiple resources during the construction of building superstructure. The rule-based reasoning algorithms, which were developed based on a typical work practice of cranes and hoists, can be adapted to other activities that involve transferring bulk materials and use cranes and/or hoists for material handling.

The assessment of a deteriorating masonry structure should lead to an objective evaluation of condition. This process is, however, inevitably subjective owing to human interpretation. The condition of the substrate and the required repairs cannot be guaranteed and may vary from building inspector to inspector. For conservation works the determination of repairs is a function of condition but also directly relates to the underpinning framework of building conservation philosophy. These are also fundamentally subjective. The combination of both condition survey subjectivity and building conservation philosophy's nebulous nature creates the potential for project aesthetic and technical divergence. This paper aims to examine this issue.

The paper presents a literature review and hypothetical case studies.

It has been shown by various researchers that a visual survey is subjective and is therefore prone to differences in reporting. In addition, the application of building conservation philosophy is seen through the perspective of the professional specifying the repairs. The combination of these two factors leads to the potential for significant project outcomes.

Subjectivity of evaluation of condition for traditional masonry structures has been little studied by academics and practitioners alike, and it is generally assumed that these yield objective, rational data. This is not necessarily the case. The application of building conservation philosophy to determine repair strategies is also a subjective process. The combination of both may lead to significant project divergence. These combined factors have never previously been discussed.