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Efflorescence formation is very common in cement-based materials. In the case of mortar, efflorescence is more studied when only Portland cement is used as a binder. However, the repair of historical heritage, as well as the construction system of some countries, usually uses mortars composed of hydrated lime and Portland cement. This study aims to determine the influence of the hydrated lime content on the incidence of efflorescence in mortars.

Mortars with 0%, 50%, and 100% lime/cement ratio were studied, using three different methods to accelerate efflorescence formation. The surface area of mortars affected by efflorescence was quantified by analysis using image software. Also, analysis of mercury intrusion porosity test, flexural tensile, compressive strength, absorption of water by capillarity, porosity, XRD and TGA was performed.

More efflorescence in mortars with a higher amount of lime in their composition was observed. The results show that the increase in the lime content reduces the flexural tensile and the compressive strength and increased the absorption of water by capillarity and the porosity of the mortars. The material formed by the efflorescence was calcium carbonate, proven by microstructural tests.

The results of greater efflorescence formation in mortars with lime are important to alert users who apply this type of material. Some type of protection must be done more rigorously for lime-cement mortars, especially concerning contact with water, since efflorescence tends to be faster for this type of material.

The purpose of this paper is to characterize the properties lightweight green air lime and marble waste mixtures, relating microstructural and chemical properties with physical development of the material, an effort has been made to simulate the structure of the different mortar reinforced by two main layers plants.

This paper presents an experimental design of response surface methodology, a model which predicts the mechanical strength and evaluate the effectiveness of bio-waste as a corrosion inhibitor to resist the steel corrosion in air lime mortars as a function of the proportion of the constituents of a new air lime mortar based on a combination of different percentages of marble waste (MRW), air lime and deferent type, layers of natural fiber reinforcement. Luffa sponge gourd and oakum hemp fiber residues capabilities in civil engineering are evaluated by combining numerical and experimental approaches for repair mortar based on air lime and marble waste. Several electrochemical techniques, mechanical strength tests and visual inspection of steel surface were performed.

The results revealed good mechanical strength and corrosion protection properties of air lime mortar containing the fiber naturel. These green wastes are considered economically feasible, as well having possessing good performance efficiency in protecting rebar reinforcement. These results were confirmed via polarization curves and electrochemical impedance spectroscopy measurements.

The prepared green air lime mortar provided good corrosion protection to the rebar. The significance of this study is to encourage the usage of solid white marble waste to prepare biomass-based repair mortar with good mechanical and anti-corrosion properties on the long term is still a big challenge.

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 purpose of this study is to fit an appropriate mathematical model to express response variables as functions of the proportions of the mixture components. One purpose of statistical modeling in a mixture experiment is to model the blending surface such that predictions of the response for any mixture component, singly or in combination, can be made empirically. Testing of the model adequacy will also be an important part of the statistical procedure.

A series of mortar using air lime, marble and ceramic sanitary waste aggregates were prepared for statistically designed combinations. The combinations were designed based on the mixture-design concept of design of experiments; this mortar is often used as a filler material in restoration projects. The aim of this work is to find an optimal composition of a paste for the manufacture of air lime mortar with ceramic and marble waste. This investigation aims to recommend mix design for air lime-based mortar, by optimizing the input combination for different properties, and to predict properties such as mechanical strength, thermogravimetric and x-ray diffraction analysis with a high degree of accuracy, based on a statistical analysis of experimental data.

This paper discusses those mortar properties that architects, contractors and owners consider important. For each of these properties, the influence of ceramic and marble waste in the air lime mortar is explored. The flexibility of lime-based mortars with waste materials to meet a wide range of needs in both new construction and restoration of masonry projects is demonstrated.

The objective of the present investigation is to recommend mixture design for air lime mortar with waste, by optimizing the input combination for different properties, and to predict properties such as compressive strength, flexural strength with a high degree of accuracy, based on the statistical analysis of experimental data. The authors conducted a mixture design study that takes into account dependent parameters such as the constituents of our air lime-based mortar where we have determined an experiment matrix to which we have connected the two responses, namely, compressive and flexural strength. By introducing the desirability criteria of these two responses, using JMP software, we were able to obtain a mixture optimal for air lime mortar with ceramic and marble waste.

The selection of lime mortars for masonry structures can be an important component of a repair or new build project. This selection is considered difficult due to the number of variables to consider during the decision‐making process and the perceived inherent complexity of the materials. The purpose of this paper is to discuss the selection process for determining suitable natural hydraulic lime repair mortars for masonry.

The paper presents a conceptual and practical framework for the determination of suitable lime mortars for repair and construction of masonry structures, drawing and building on relevant, literature and existing best practice guidance on specification.

The use of various relatively newly produced data sets pertaining to durability can aid in the appropriate selection of lime mortars. These determinants must however, be correlated with traditional evaluation of exposure levels, building detailing and moisture handling performance. Building condition survey of the existing fabric is essential to enable refinement of the selection process of these mortars. The adjustment of the initially identified mortars highlighted in the best practice guide may potentially benefit from modification based on the aforementioned factors.

Whilst data exist to help the practitioner select hydraulic lime mortars they have never been correlated with the tacit and expressed protocols for survey and the evaluation of the performance of structures.

The purpose of this paper is to address the issue of perceptions of suitability of different materials for a repair. The use of highly cementitious materials in the repair of historic masonry is causing great concern due to their incompatibility with adjacent stone and the associated accelerated deterioration which results from their use. The relatively recent development of so‐called “restoration mortars” based on a “mix and go” application, combined with the enhanced weathering of stone in a changing climate, may be contributing to the use of “plastic” repair materials on stone across Scotland.

Following a literature review, case studies of repairs are presented to highlight the advantages and disadvantages of using such materials, and comparisons are made with the alternative options.

The case studies presented highlight the use of a number of different stone repair materials, sometimes in combination with stone replacement, representing functional and philosophical approaches to masonry repair. However, the research has also highlighted the increasing use of plastic repairs for large‐scale repair including façade rendering, which fail to incorporate these systematic and informed approaches, and can ultimately lead to failure of repairs.

An evaluation of the current standing of the materials, methods and the extent of this type of repair, is vital for the substantiation of further research, and to enhance the empirical knowledge of in‐use performance, longevity and failure. The increasing emergence of restoration mortars, and their manufacture and supply on an international scale, highlights the global impact and relevance of this research.

The purpose of this paper is to investigate the performance of new and innovative crystallising materials, so-called moisture blockers, in protecting masonry structures from water ingress.

Two masonry wells were constructed: one with lime mortar and the other with cement-based mortar in order to hold water inside, and then a moisture blocking product was applied at dry and wet conditions to the negative hydrostatic pressure side. The moisture levels of both, the surfaces and the substrate, were then observed for 14 days.

Results demonstrated that moisture blocking materials are effective methods in reducing the levels of surface moisture for bricks, mortar-brick interface and mortar.

Moisture blockers use the available water in the masonry to block the passage of water to the surface of the masonry, filling pores, cracks and spaces at the interface between mortar and bricks. This approach will deliver a wider understanding of how water-based moisture blockers work and the scenarios in which they are best applied. The pursuit of possible environmentally friendly and sustainable materials for use in the construction industry is the key driver of this research.

Outlines a survey of site practice and of mortar compositions undertaken in the North East of England by the Construction Industry Division of the Department of the Environment and sponsored by the National House Building Council, designed to investigate the type of mortars specified for housing construction and the extent to which site‐mixed mortars achieved the specification. Discloses the results of the survey and indicates that a relatively large proportion of such mortars will contain somewhat less cement than specified.

This paper presents the outcomes of the international project “Protecting Landscape Heritage: a requalification project as an instrument for the re-birth of Quang Tri Old Citadel in Vietnam”, achieved with scientific cooperation between the Università Politecnica delle Marche (Italy) and Hue University of Sciences (Vietnam) funded by the Italian Ministry of Foreign Affairs and International Cooperation and Ministry of Science and Technology of Vietnam. The research focuses on the Quang Tri Citadel, founded in 1809 and now in an advanced state of degradation.

For the purpose of rehabilitation, the wide multidisciplinary project first examined the historical context of the military model, the architectural aspects of the structure, the characterization of the existing materials, the degradation levels of different parts, and, finally, a proposal of the suggested interventions.

The original structure and geometry were extrapolated and studied. Building materials were produced with nearby raw materials. Firing temperatures of bricks ranged from 800 to 1,000 °C, hydraulic lime was supposed the binder of the mortar with a calcination temperature lower than 1,000 °C. Damage assessment was provided and after these analyses a requalification project was proposed so the cultural heritage can play a role for the future in the dialog between different cultures.

The requalification project achieved by an integrated analytical approach defines aspects in relation to the restoration of the structures, enabling compliance with the geometry, techniques, building materials used in the original construction and allowing its guardianship and management to align with the historical context of the architectural heritage.