Effect Of ECC overlay on the strength of burnt clay brick masonry

The construction industry has undergone significant technological transformations aimed at improving productivity, reducing costs, and increasing sustainability. Among these innovations, plasterboard (drywall) systems have emerged as an alternative to conventional brick masonry for vertical partitions. This review article presents a comprehensive comparative analysis between plasterboard systems and traditional brick masonry, focusing on structural performance, economic viability, construction speed, environmental impact, thermal and acoustic behavior, durability, and practical application in the Brazilian context. The study synthesizes technical literature, normative standards, and cost analyses to evaluate the advantages and limitations of both systems. Results indicate that while conventional masonry remains widely used due to its mechanical resistance and cultural acceptance, plasterboard systems offer significant benefits in terms of construction speed, reduced structural load, material efficiency, and design flexibility. The review concludes that the selection between systems should consider project-specific requirements, environmental conditions, and cost–benefit analysis, rather than relying solely on traditional practices.

ABSTRACT The expansion of global infrastructure is contributing to the depletion of natural resources and other environmental concerns, primarily owing to the generation of construction and demolition waste. Recycling and reuse of this waste offers a feasible approach to resource conservation and enhancement of sustainability. In this study, an attempt was made to explore the feasibility of crushed brick masonry debris (CBM) for the development of recycled masonry concrete blocks (RCB). CBM as fine aggregate in varying substitution levels were incorporated to develop RCB, which were assessed for physical, mechanical, and durability properties. The results revealed that the utilization of CBM in concrete blocks exhibits satisfactory performance across all parameters, with the 50–75% CBM substitution showing optimal results. RCBs displayed dimensional stability, appropriate densities, and water absorption within acceptable limits. Compressive strength of the blocks ranged between 4.68 and 6.14 MPa for various substitution levels, better than commercial blocks. Microstructural analysis revealed beneficial crystal formations supporting mechanical performance. Notably, RCBs showed significant reductions in embodied energy (47.65–64.59%) and embodied carbon (5.67–31.56%) compared to conventional blocks. Thus, utilizing recycled materials in the manufacturing of concrete blocks not only showcases viability but also enhances the progression toward sustainability.

In many existing brick buildings, severe dampness of the walls is often observed. One of the most common causes of severe dampness is a lack of adequate damp-proofing and frequent flooding. The strong capillary water absorption capacity causes that in some cases, brick masonry reaches the full water saturation state. Strong moisture has a negative impact on the mechanical parameters of brick masonry. However, the scale of this effect in brick buildings is an issue that is still largely unknown. In this paper, results of research conducted on brick, mortars, and masonry specimens are presented. The material specimens were cut out from a historic military building and tested in air-dry and wet conditions. Studies have shown that strong moisture significantly reduces compressive strength in all the tested materials. The reduction in compressive strength of the brick masonry ranged from 6% to 39%. Based on experimental results, this paper proposes a method for predicting the reduction in compressive strength of brick masonry caused by significant moisture. This method is based on testing specimens of brick and mortar taken from the structure and can be classified as a minor-destructive technique. Therefore, it can be particularly useful in assessing the sensitivity to the effects of significant moisture in historic structures, where the collection of larger masonry specimens for testing is not permitted due to conservation reasons.

Inappropriate bricklaying techniques can result in extruded mortar joints, which may partially fill the air gaps within brick veneer timber frame walls. This leads to an unintended connection or “bridge” between the brick masonry cladding and its adjacent layer (such as insulation or weather-resistant barriers). This bridging effect compromises the capillary break function of the air gap, allowing water to reach adjacent layers and intensifying the impact of water penetration, under wind-driven rain (WDR) conditions. This study employs a probabilistic analysis in combination with a machine learning metamodel to investigate the impact of extruded mortar joints on mould growth. The metamodel, developed using the random forests (RF) machine learning algorithm, is used to predict the maximum mould index (MMI). In addition, this study assesses the effects of two different water penetration criteria—ASHRAE and experimental study-based (ES)—on extruded mortar joints under climatic conditions in Gothenburg, Sweden. In order to figure out how different orientations affect the analysis; the study examines the case study from four different orientations. The findings showed that the ES and ASHRAE criteria were in agreement for orientations with substantial WDR loads (e.g. south). On the other hand, the ASHRAE criteria illustrated a higher MMI than the ES criteria in walls facing orientations with relatively small WDR loads (e.g. north). Furthermore, an increased extruded mortar depth and higher MMI were shown to be positively correlated by the linear and non-linear mould sensitivity analyses. However, depending on the WDR loads (or different orientations) and chosen water penetration criteria, this correlation’s strength can vary. The air change rate (negative correlation), the solar absorption coefficient (negative correlation), the WDR’s reduction/splash coefficient (positive correlation), and the thermal conductivity of the Rockwool insulation (positive correlation) were additional important variables influencing the MMI.

This paper investigates the domestic architecture of ancient Pundranagar through an ethno-archaeological reinterpretation of existing archaeological excavation data rather than new field excavation. Drawing on structural remains, material findings, and comparative vernacular traditions of northern Bengal, the study constructs a hypothesis on dwelling patterns during the Pāla period. While previous scholarship has largely focused on fortifications, monuments, and administrative structures, residential architecture remains poorly documented due to fragmentary evidence and limited household artifacts. By synthesizing secondary excavation data from the 1928–31 ASI investigations and the 1990s France–Bangladesh joint excavations, alongside living traditions of mud-and-brick construction, this paper proposes a more nuanced understanding of domestic spaces. The study argues that ordinary dwellings likely relied predominantly on unburnt clay walls and mixed-material construction, while burnt brick masonry was restricted to elite households and institutional structures. Roofing systems, semi-open porticos, and courtyard-based layouts are interpreted through both archaeological traces and continuing regional practices. This interdisciplinary approach offers a refined hypothesis of the socio-spatial fabric of Pundranagar and contributes to the broader discourse on ancient urbanism in Bengal. Journal of the Asiatic Society of Bangladesh (Hum.), Vol. 70(2), December 2025, pp. 171-191

Experimental study on shear behavior of brick masonry strengthened with CFRP flexible tendons embedded in mortar joints

ABSTRACT Uganda faces a substantial housing deficit, and escalating construction costs resulting from unsustainable extraction of construction materials and inadequate management of plastic and sawdust waste. This study evaluates the compressive strength and cost effectiveness of Plastic Bottle Brick (PBB) masonry walls as a potential substitute for conventional concrete block walls in Mbale City, Uganda. The work specifically addresses the limited empirical evidence concerning the behaviour of vertically oriented confined PBB units incorporating uncompressed air (EB), sawdust (SD) and pit sand (PS). Compressive strength testing showed that PS walls achieved a strength of 0.6 ± 0.02 MPa, comparable to hollow concrete block (HCB) walls (0.6 ± 0.06 MPa). SD and EB walls exhibited lower strengths of 0.3 ± 0.05 MPa and 0.3 ± 0.03 MPa, respectively, below the strength of solid concrete block (SCB) walls (0.8 ± 0.03 MPa). All PBB walls demonstrated higher failure strains (1.8–2.0%) than concrete block walls (1.0–1.2%). The cost-benefit analysis considering materials, labour, time utilisation and carbon emissions costs found that EB blocks were the most economical (USD 3.22/UGX 11,694), while SCB were the least economical (USD 7.97). PBB production was commercially feasible, with casting time only 17% slower than conventional block production.

This study presents the development and evaluation of a 3D-printable alkali-activated mortar formulated with brick masonry waste, utilized as both binder and aggregate to mitigate the environmental burden of Portland cement and reduce reliance on scarce industrial by-products. Mixtures with 50–80% recycled brick content were tested for fresh rheology, mechanical strength, thermal conductivity, and 3D-printability. Using the measured properties, finite-element thermal analyses were performed on five wall geometries with varying void configurations. The results indicate that increased void ratios substantially lower thermal transmittance, while the geometry and distribution of contact points critically influence heat transfer. The best-performing design achieved a U-value of ~4.1 W/m²K, corresponding to a 75% reduction compared to a solid wall of equal thickness. Complementary cradle-to-gate life-cycle assessment (LCA), confirmed reductions of 70–80% in embodied environmental impacts following geometric optimization. Collectively, these findings highlight the potential of integrating waste-derived geopolymer binders with optimized 3D-printed wall patterns to produce thermally efficient building envelopes. The outcomes support sustainable construction pathways and underscore the relevance of extending future research to explore multi-functional optimization (e.g., acoustic and structural performance), and the integration of passive insulation strategies to further enhance these 3D-printed systems.

A UHP-ECC surface layer combined with a wire mesh strengthening method for brick masonry walls: Experimental investigation on seismic behavior

Numerical Study on Load-Bearing Capacity of Brick Masonry Walls with Different Mortar Mix Ratios

Investigation on the mechanical and shrinkage performance of UHP-ECC for existing brick masonry wall reinforcement

Effectiveness of textile reinforced (TR) systems based on sustainable mortar for the confinement of clay brick masonry columns: a preliminary study

Wall structures are commonly seen in everyday life, with brick masonry and concrete being the most frequently used materials. However, in the face of natural disasters such as earthquakes, floods, or other extreme situations, these buildings may collapse, leading to serious casualties and significant property damage. This paper aims to discuss the research and development of new wall materials and explore the compressive strength and seismic performanceof modern wall materials in natural disasters. It is found that modern wall materials have witnessed significant improvement in seismic performance, making them especially suitable for meeting lighting needs during nighttime earthquakes. The research and development of self-luminous glass fibre-reinforced plastic (GFRP) composite materials can provide lighting during power outages, enhancing residents' sense of security. In addition, inspired by bioluminescence, specifically the light-emitting mechanism of fireflies, a new type of self-luminous material has been developed through the reaction between luciferin and luciferase. It offers an environmentally friendly and efficient lighting solution during blackouts.

This paper presents a comprehensive analysis of damage to buildings and infrastructure resulting from military actions, with a particular emphasis on modern conflicts and their devastating consequences. The primary focus is on a profound examination of various factors causing deformation and destruction: from the destructive effects of explosive shock waves and dynamic loads to mechanical impacts (shrapnel, direct hits) and intense thermal factors (fires, high-temperature exposures).The study encompasses a representative sample of over 150 structures of various types, located in active combat zones. This enabled a detailed examination of typical failure and degradation mechanisms in key structural systems, such as panel buildings, traditional brick masonry, monolithic and precast reinforced concrete structures, as well as lightweight frame and rapidly assembled constructions. Key findings confirm the empirically established pattern that the intensity of damage decreases exponentially with increased distance from the explosion's epicenter, which is crucial for hazard zoning. A significant correlation was also established between the nature of the consequences, the type of explosion (airburst, ground-level, subsurface), its power, and the structural features that determine a building's inherent resilience to external influences. To accurately assess the parameters of explosive waves, including their pressure, impulse, and duration, advanced methods were employed. These methods combine empirical formulas derived from field tests with high-precision numerical modeling using the finite element method (FEM). Based on the comprehensive analysis, a set of practical recommendations is proposed. They include the use of more durable, ductile, and energy-absorbing materials, the retrofitting and strengthening of existing buildings, and the optimization of urban planning solutions, considering principles of protective design and infrastructure dispersion. The objective of this work is not only to document and analyze damages but also to significantly improve existing methodologies for calculating structural responses to blast loads. Furthermore, the study investigated the impact of secondary factors such as collapses, ground deformations, and subsequent settlements, which often accompany primary destructions and exacerbate the overall condition of affected objects.

The authors analyzed the architectural and structural features of the “Dytiachyi Svit” department store in Kharkiv—a historic building and a creative legacy of architect O. Linetsky. The study focuses on the four-story “New Passage” building (original designation), recognized as an architectural monument and located at Constitution Square, 9, Kharkiv. The terrain of the building’s location is characterized by significant elevation changes, sloping toward the Kharkiv and Lopan rivers. Construction began in the early 20th century under architect M. Piskunov, with later work in the 1920s by O. Linetsky, who introduced a more expressive and modern interpretation of commercial architecture. Linetsky’s design emphasized vertical rhythm and stepped window framings, integrating the building into its urban context through horizontal elements at the plinth and third-floor levels. This modernist structure, one of Kharkiv’s finest trade complexes, housed various shops and became colloquially known as the “Indian Tomb” due to its grey-violet facade tones, which created a distinctive and memorable appearance for local residents and visitors. The study analyzes the building’s spatial organization, which follows the traditional passage layout—a central corridor flanked by shops, illuminated by a glass roof that ensured natural daylight throughout the interior. The department store comprises four characteristic blocks with distinct structural and functional features. These include a four-story framed building facing Constitution Square, a central hall, and additional wings connected by overhead walkways that optimized circulation and unified the composition. Detailed attention is given to the materials and structural elements, including brick masonry, monolithic reinforced concrete floors, and diverse roof designs that reflect both the technological capabilities and architectural preferences of the period. Restorations after World War II, notably by architect B. Miroshnichenko, altered the facade’s symmetry and introduced new architectural accents while preserving the overall character of the historic building. The research highlights the unique architectural and structural solutions of the “Dytiachyi Svit” building, emphasizing its significance in the urban and historical landscape of Kharkiv and its continued relevance as an example of early 20th-century commercial architecture.

ABSTRACT Masonry structures are traditional buildings made up of heterogeneous and anisotropic components, which create various challenges in design, construction and analysis. This study aims at investigating the out-of-plane behavior of walls constructed with low-strength mortar through both experimental and numerical approaches. In this context, the effects of wall slenderness, shape and openings on out-of-plane behavior were explored. Different wall slenderness ratios (height/length) and door/window openings were considered in the wall models. Masonry wall models were experimentally tested on a tilting table and further analyzed using ABAQUS software. Six wall models each of U, L and I shapes with two-side, one-side and no support respectively were constructed. Each model was tested at least twice and experimental and analysis results were compared. The results showed that increasing wall slenderness (from 1.33 to 2) led to 10–50% reductions in lateral load capacity, especially in U-shaped walls. More door and window openings further decreased capacity and enlarged failure zones. A single supporting wall increased capacity by 3.5 times, while two supports raised it 5.5 times. More ductile behavior was observed due to the supporting walls, which prevented early collapse. The findings emphasize the critical role of support walls in reducing capacity losses.

Experimental response of unreinforced brick masonry walls to moderate-velocity point-load and line-load impacts

The UK’s commitment to achieving net zero by 2050 stresses the necessity for highly energy-efficient building structures, emphasising a fabric-first approach. Inadequate design or execution can lead to unintended consequences, particularly condensation within the building envelope, posing risks of structural damage and mould growth. This paper delves into the intersection of precise design and a sustainable future, highlighting the crucial role of condensation risk analysis (CRA). CRA is vital for assessing moisture activity, predicting condensation and implementing measures to avoid or minimise associated risks. The study evaluates various moisture sources and mitigation strategies, focusing on rain ingress, construction moisture, rising damp, internal and external vapour pressure and moisture-laden warm internal air. Comparing two widely used CRA methods, the dewpoint method and hygrothermal numerical simulation (HNS), the paper emphasises their strengths and applications. Practical guidance on selecting the right CRA method based on project-specific scenarios, fabric types and moisture risks is provided. Case studies demonstrate the application of both methods in a conventional timber frame with a brick façade and internal wall insulation on solid brick masonry. Legal and regulatory considerations, including BS 5250:2021, are discussed, highlighting the importance of adherence to standards in effectively managing moisture-related challenges. The paper concludes by emphasising the significance of CRA in ensuring the longevity and efficiency of building envelopes, serving as a valuable resource for building surveying professionals.

Abstract To evaluate the seismic performance of masonry walls strengthened with a steel mesh-sprayed Engineered cementitious composite (ECC) layer, low reversed cyclic loading tests were conducted on walls strengthened with steel mesh-ECC and steel mesh-mortar overlays and compared with an unstrengthened specimen. Considering the superior mechanical properties of ECC and the importance of the wall-overlay bond, a novel strengthening method is proposed in which a steel mesh is embedded in the ECC layer and anchored to the wall through tie bars to enhance interfacial bonding and ensure composite action under lateral loading. The study focused on the shear load-bearing capacity, ductility, energy dissipation capacity, and failure patterns of the walls. The results indicated that the failure pattern of the unstrengthened masonry wall was shear failure, accompanied by diagonal cracks. The masonry wall strengthened by steel mesh-ECC layer underwent bending failure. Compared with the unstrengthened specimen, the peak load, ductility coefficient, and yield load of specimen strengthened with steel mesh-mortar layer increased by 25.38%, 27.81%, and 22.22%, respectively, while the peak load, ductility coefficient, and total cumulative energy dissipation of specimen strengthened with steel mesh-ECC layer improved by 60.17%, 48.34%, and 566%, respectively. The hysteresis curve of the strengthened masonry walls was more stable, the stiffness degradation curve was smoother, and the equivalent viscous damping coefficient and cumulative energy dissipation increased at each displacement level. The masonry wall strengthened with steel mesh-ECC layer exhibits enhanced seismic performance. This research provides a technical reference for the steel mesh-ECC strengthening in masonry walls.