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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 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.

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.

Ancient theatres and odea are one of the most significant and creative socio-cultural edutainment centres of human history that are still in use. They stood and served as huge multi-functional structures for social, religious, propaganda and political meeting space. Meanwhile, ancient theatres’ sites have an intrinsic value for all people, and as a vital basis for cultural diversity, social and economic development, they should continue to be a source of information for future generations. Though, all places with ancient theatre heritage should be assessed as to their potential risk from any anthropogenic or natural process. The paper aims to discuss these issues.

The main paper’s objective is to discuss mainly the anthropogenic and technical risks, vulnerability and impact issues on the ancient classical theatres. While elaborating on relevant recent studies, where the authors were involved in ERATO and ATHENA European projects for ancient theatres and odea, this paper provides a brief overview of the main aspects of the anthropogenic qualitative risks and related issues for selected classical antiquity theatres. Some relevant cases are critically presented and investigated in order to examine and clarify the main risk mitigation issues as an essential prerequisite for theatre heritage preservation and its interface with heritage reuse.

Theatre risk mitigation is an ongoing and challenging task. By preventive conservation, theatre anthropogenic qualitative risks’ management can provide a framework for decision making. The needed related guidelines and recommendations that provide a systematic approach for sustainable management and planning in relation mainly to “ancient theatre compatible use” and “theatre technical risks” are analysed and presented. This is based on identification, classification and assessment of the theatre risk causes and contributing factors and their mitigation.

The paper also suggests a new methodological approach for the theatre anthropogenic qualitative risk assessment and mitigation management, and develop some recommendations that provide a systematic approach for theatre site managers and heritage experts to understand, assess, and mitigate risks mainly due to anthropogenic and technical threats.

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.

Reuse of construction and demolition (C&D) waste as aggregates is becoming increasingly popular for a number of environmental and economic reasons. The purpose of this paper is to explore this topic.

In this study, structural‐ and pavement‐grade portland cement concrete (PCC) mixtures were developed using crushed recycled brick masonry from a demolition site as a replacement for conventional coarse aggregate. Prior to developing concrete mixtures, testing was performed to determine properties of whole clay brick and tile, as well as the crushed recycled brick masonry aggregate (RBMA), and a database of material properties was developed.

Concrete mixtures exhibiting acceptable workability and other fresh concrete properties were obtained, and tests were performed to assess mechanical properties and durability performance of the hardened concrete. Results indicated that recycled brick masonry aggregate concrete (RBMAC) mixtures can exhibit mechanical properties comparable to that of structural‐ and pavement‐grade PCC containing conventional coarse aggregates.

Results for durability performance were mixed, but additional testing to evaluate durability performance is recommended.

Although RBMAC has been untested in field applications, results of laboratory studies performed to date indicate that this material shows promise for use in pavement and structural applications. Future testing of RBMAC in both laboratory and field settings will allow stakeholders to gain a comfort level with its properties, identify specific potential uses, and establish guidelines that will assist in ensuring acceptable service life performance.

From the standpoint of sustainability, use of recycled materials as aggregates provides several advantages. Landfill space used for disposal is decreased, and existing natural aggregate sources are not as quickly depleted. Use of recycled aggregates in lieu of virgin quarried aggregates can potentially result in a lower embodied energy of the concrete, although this is often dependent on hauling costs. This particularly holds true if the methodology used to compute the embodied energy of a structure accounts for the “recovery” of energy at the end of its service life.

Reinforced concrete structural frames with masonry infills (infill-frames) are commonly used for construction worldwide. While the behavior of such frames has been studied extensively in the context of earthquake loading, studies related to their fire performance are limited. Therefore, this study aims to characterize the behavior of infill-frames under fire exposure by presenting a state-of-the-art literature review of the same.

Both experimental and computational studies have been included with a special emphasis on numerical modeling (simplified as well as advanced). The cold behavior of the infill-frame and its design requirements in case of fire exposure are first reviewed to set the context. Subsequently, the applicability of numerical modeling strategies developed for modeling cold infill-frames to simulate their behavior under fire is critically examined.

The major hurdles in developing generic numerical models for analyzing thermo-mechanical behavior of infill-frames are identified as: lack of temperature-dependent material properties, scarcity of experimental studies for validation and idealizations in coupling between thermal and structural analysis.

This study presents one of the most popular research problems connected with practical and reliable utilization of numerical models, as a good alternative to expensive traditional furnace testing, in assessing fire resistance of infill-frames. It highlights major challenges in thermo-mechanical modeling of infill-frames and critically reviews the available approaches for modeling infill-frames subjected to fire.

This paper aims to contribute to the discussion of the experimental campaigns on Cultural Heritage buildings. By adopting integrated procedures it is possible to limit the invasiveness of the destructive techniques leading to reliable results. The purpose is the proper definition of the structural system, which represents the starting point of the following analysis's phases, not treated in this work. A methodology based on normative references and acknowledged non-destructive and partial destructive strategies has been conceived. The latter aims to an accurate comprehension of the structural information.

An integrated approach for the structural assessment of cultural heritage buildings is presented. The methodology defines an interdisciplinary procedure based on normative references, non-destructive and minor-destructive techniques. A funnel-shaped workflow is developed to characterize the structural system of the buildings. The non-destructive campaigns are widely extended. Then, in-depth analysis concerning partial demolitions and minor-destructive tests are performed. The dynamic identification of the building is executed to detect its global response. The final validation of the assumed mechanical values is obtained by comparing the experimental modes coming from the ambient vibrations and the analytical modes of the structural modelling.

This research belongs to the Protocol signed between the Municipality of Florence and Department of Earth's Science and Department of Architecture of the University of Florence for the seismic vulnerability assessment of relevant and strategic buildings.

The descripted methodology is targeted for monuments and special buildings where the use of destructive techniques is not possible or unrecommended.

Social implications are related to the conservation of Heritage buildings. The latter deals with: (1) risk assessment of the targeted buildings towards different hazard sources (e.g. earthquakes, floods); (2) knowledge path developed through non-invasive diagnostic campaigns oriented to the conservation of the manufact. Furthermore, the paper encourages towards the recognition of non-destructive techniques and ambient vibration tests for the achievement of higher knowledge levels.

This paper defines a funnel-shaped procedure defining hierarchical roles between the different available strategies. The originality of this contribution is firstly related to the methodological flowchart. It is targeted to limit the invasive tests and consequently achieving accurate levels of knowledge. Secondly, some novelty can be found in the adoption of improvement parameters from a regional database adopting a Bayesian approach.

To contribute for a reliable estimation of the compressive strength of unreinforced masonry from the properties of the constituents (units and mortar).

Sophisticated non‐linear continuum models, based on damage, plasticity, cracking or other formulation, are today standard in several finite element programs. The adequacy of such models to provide reliable estimates of masonry compressive strength, from the properties of the constituents, remains unresolved. The authors have shown recently that continuum models might significantly overestimate the prediction of the compressive strength. Hence, an alternative phenomenological approach developed in a discrete framework is proposed, based on attributing to masonry components a fictitious micro‐structure composed of linear elastic particles separated by non‐linear interface elements. The model is discussed in detail and a comparison with experimental results and numerical results using a standard continuum model is provided.

Clear advantages in terms of compressive strength and peak strain prediction were found using the particle model when compared with standard continuum models. Moreover, compressive and tensile strength values provided by the model were found to be particle size‐ and particle distortion‐independent for practical purposes. It is also noted that size‐dependent responses were obtained and that shear parameters rather than tensile parameters were found to play a major role at the meso‐level of the phenomenological model.

This paper provides further insight into the compressive behaviour of quasi‐brittle materials, with an emphasis on the strength prediction of masonry composites. Reliable prediction of masonry strength is of great use in the civil engineering field, allowing one to reduce experimental testing in expensive wallets and to avoid the usage of conservative empirical formulae.

The purpose of this paper is to provide a method to predict the situation of a loaded element in the compressive stress curve to prevent failure of crucial elements in load-bearing masonry walls and to propose a material model to simulate a compressive element successfully in Abaqus software to study the structural safety by using non-linear finite element analysis.

A Weibull distribution function was rewritten to relate between failure probability function and axial strain during uniaxial compressive loading. Weibull distribution parameters (shape and scale parameters) were defined by detected acoustic emission (AE) events with a linear regression. It was shown that the shape parameter of Weibull distribution was able to illustrate the effects of the added fibers on increasing or decreasing the specimens’ brittleness. Since both Weibull function and compressive stress are functions of compressive strain, a relation between compressive stress and normalized cumulative AE hits was calculated when the compressive strain was available. By suggested procedures, it was possible to monitor pretested plain or random distributed short fibers reinforced adobe elements (with AE sensor and strain detector) in a masonry building under uniaxial compression loading to predict the situation of element in the compressive stress‒strain curve, hence predicting the time to element collapse by an AE sensor and a strain detector. In the predicted compressive stress‒strain curve, the peak stress and its corresponding strain, the stress and strain point with maximum elastic modulus and the maximum elastic modulus were predicted successfully. With a proposed material model, it was illustrated that the needed parameters for simulating a specimen in Abaqus software with concrete damage plasticity were peak stress and its corresponding strain, the stress and strain point with maximum elastic modulus and the maximum elastic modulus.

The AE cumulative hits versus strain plots corresponding to the stress‒strain curves can be divided into four stages: inactivity period, discontinuous growth period, continuous growth period and constant period, which can predict the densifying, linear, non-linear and residual stress part of the stress‒strain relationship. By supposing that the relation between cumulative AE hits and compressive strain complies with a Weibull distribution function, a linear analysis was conducted to calibrate the parameters of Weibull distribution by AE cumulative hits for predicting the failure probability as a function of compressive strain. Parameters of m and θ were able to predict the brittleness of the plain and tire fibers reinforced adobe elements successfully. The calibrated failure probability function showed sufficient representation of the cumulative AE hit curve. A mathematical model for the stress–strain relationship prediction of the specimens after detecting the first AE hit was developed by the relationship between compressive stress versus the Weibull failure probability function, which was validated against the experimental data and gave good predictions for both plain and short fibers reinforced adobe specimens. Then, the authors were able to monitor and predict the situation of an element in the compressive stress‒strain curve, hence predicting the time to its collapse for pretested plain or random distributed short fibers reinforced adobe (with AE sensor and strain detector) in a masonry building under uniaxial compression loading by an AE sensor and a strain detector. The proposed model was successfully able to predict the main mechanical properties of different adobe specimens which are necessary for material modeling with concrete damage plasticity in Abaqus. These properties include peak compressive strength and its corresponding axial strain, the compressive strength and its corresponding axial strain at the point with maximum compressive Young’s modulus and the maximum compressive Young’s modulus.

The authors were not able to decide about the effects of the specimens’ shape, as only cubic specimens were chosen; by testing different shape and different size specimens, the authors would be able to generalize the results.

The paper includes implications for monitoring techniques and predicting the time to the collapse of pretested elements (with AE sensor and strain detector) in a masonry structure.

This paper proposes a new method to monitor and predict the situation of a loaded element in the compressive stress‒strain curve, hence predicting the time to its collapse for pretested plain or random distributed short fibers reinforced adobe (with AE sensor and strain detector) in a masonry building under uniaxial compression load by an AE sensor and a strain detector.