Concrete Block Wall Research Articles

Towards the use of natural thermal insulation on the exterior of vertical building walls in desert regions: A case study in the city of Bechar, Algeria

The use of natural-based exterior thermal insulation systems constitutes a significant challenge for achieving energy efficiency of construction. The purpose of this article is to propose new exterior thermal insulation solutions based on natural materials such as wood wool, cellulose wadding, expanded cork, hemp fiber, and sheep’s wool, in order to minimize energy consumption, address durability concerns, maintain thermal comfort, and promote the use of natural materials in thermal insulation system designs. The methodology followed consists of presenting a comparative numerical study of different exterior insulation techniques (ETI) using a dynamic thermal simulator for desert regions. The study evaluated ETI systems for vertical walls attached to a concrete block wall, including one EPS system with coating (wet process) and six systems with cladding (dry process). The results show that applying exterior insulation to walls using the two cladding systems based on hemp fiber and sheep wool resulted in a total reduction in building energy consumption of 42.21% and 42.81%, respectively. These results confirm the effectiveness of natural materials in improving the energy performance of buildings, particularly the system based on sheep wool.

Influence of Opening and Boundary Conditions on the Behavior of Concrete Hollow Block Walls: Experimental Results

The assembled pattern of concrete hollow building blocks contributes to the wall structure’s durability. This paper presents experimental research on the behavior of concrete hollow block walls. The experimental work included testing four concrete hollow block wall panels with different opening sizes. Constant vertical axial load was applied on top of the wall panels until failure, characterized by boundary conditions. The results showed that the presence of openings reduced the strength of the wall panels; it was possible to observe these differences since the opening area was between 20 and 40% of the gross wall panel area. It was also observed that while the opening percentage had a significant impact on the strength of the wall, the boundary conditions had a less substantial impact on the overall wall response. A high localized concentration of stress was observed at the top corners of the wall panels and a high stress concentration was also observed along the vertical sides of the openings. Variation in the number and the shape of the openings often changed the failure mechanism in the wall panels, even when the percentage area of the opening remained constant. The wall panels A1-B2 reached peak stress levels at 0.019 MPa, 0.036 MPa, 0.056 MPa, and 0.030 MPa. The equivalent peak strains were 0.018, 0.011, 0.012, and 0.010 respectively. This research established significant data and is expected to help in the design and analysis of axially loaded unreinforced masonry walls with openings.

Wall and air conditioner combination for the best energy and economic performance: Methodology demonstration for high-rise residential buildings

Enhancing energy efficiency of any system with affordable measures is always a ‘win-win’ option, specifically for systems consuming large amount of energy. With increasing population and economic growth, rapid urbanization is inevitable, more so in developing countries. Due to higher population density and scarcity of available land, high-rise residential and commercial buildings are now increasing in big cities. Building energy efficiency has eventually emerged as a critical issue for such high-rise buildings. Space cooling consumes a huge amount of energy for high-rise buildings in tropical countries. Selection of masonry materials for exterior walls with matching air conditioners should be optimized for the best energy efficiency vis-à-vis least cost for high-rise buildings. Such a study to determine the optimized solution is reported using data of ten typical high-rise residential buildings in the warm-humid climate of Kolkata, India. The methodology followed is an integrated iterative process involving whole building energy simulation to determine the optimum performance out of different possible combinations of building walls (i.e., passive measure) and selection of corresponding air conditioners (i.e., active measure) for simultaneous best energy efficiency and minimum costing. Results show that the combination of autoclaved aerated concrete block wall and 5-star split air conditioner emerges as the optimum, being 37.53% more energy efficient and 24.27% more cost effective than the typically practiced baseline option. The required 29.47% higher capital investment is well compensated for lower annual expenditure for operational energy when fifteen years’ cash flow is considered. The study shows an integrated methodology for deciding the optimum combination of passive and active measures for the possible best energy performance at a minimum cost at the early design stage of high-rise buildings.

Quasi-static experimental study on reinforcing aerated concrete block walls through steel wire Rope-Polymer mortar surface layer cross-strip method

A total of five aerated concrete block walls were subjected to quasi-static experiments to explore the seismic performance of aerated concrete block walls reinforced through the steel wire rope-polymer mortar surface layer cross-strip method. The failure process, hysteresis loop, skeleton curve, stiffness, and ductility of different specimens were comparatively analyzed based on low cyclic loading tests. The results revealed that the cross strip on the steel wire rope-polymer mortar surface layer could enhance the shear bearing capacity and stiffness of aerated concrete block walls but failed to significantly improve their ductility and energy-dissipating capacity. Moreover, a calculation method for the shear bearing capacity of aerated concrete block walls reinforced using the cross strip on the steel wire rope-polymer mortar surface layer was proposed, which exhibited favorable prediction accuracy.

Seismic Performance of Desert-sand Autoclaved Aerated Concrete Block Wall Constrained by Precast Integral Construction Column

Considering the structural types and construction techniques used in common residential buildings in Xinjiang, the paper proposes a novel masonry structure, i.e., desert-sand AAC blocks constrained by a precast integral construction column. In order to study the seismic performance of the structure, five wall specimens with different constraints are designed and fabricated and further compared and analyzed in terms of failure mode, hysteretic performance, energy dissipation capacity, ductility, stiffness degradation, and other performance indexes. It has been determined from the results that under horizontal low-cycle repeated loading, the main failure cracks of the desert-sand AAC block wall constrained by the precast integral construction column are intersecting oblique cracks, and the cracks in wall failure penetrate along concrete blocks. The stiffness degradation rate of the wall constrained by the water-resistant gypsum construction column gradually decreases with increasing vertical compressive stress. The wall constrained by the water-resistant gypsum construction column with arranged steel bars has a desirable ductility. Under the same vertical compressive stress, the wall constrained by the water-resistant gypsum precast construction column with arranged steel bars has a significant energy dissipation capacity from cracking to the ultimate state. (4) A restoring force model is built for desert-sand AAC block walls constrained by the precast integral construction column using a three-fold line model, offering technical support for the elastoplastic seismic analysis of structures.

Exploring energy-efficient building solutions in hot regions: A study on bio-phase change materials and cool roof coatings

Creating low-energy buildings in arid, hot desert climates like Kuwait poses significant challenges. This research examines the potential of Bio-PCMs and cool roof coatings as energy-saving methods in three hot climate locations, using both experimental and computational approaches. Two identical portable cabins were meticulously constructed, and their thermal properties were analysed under two different cooling conditions. These cabins offer a unique testing ground for various energy-saving techniques, as their thermal similarity has been experimentally confirmed. A six-zone model was developed in TRNSYS software to study Bio-PCM integrated walls. The findings for the desert climate of Kuwait and subtropical climate of Rockhampton, Australia, demonstrated the best performance with autoclaved aerated concrete block walls, achieving energy performance indices of 761.7 and 496.3 kWh/m2/year, respectively. Bio-PCMs integration in three positions within walls and roof were examined, which were yielded energy savings of 22%, 23%, and 53% in Kuwait, Australia, and India, respectively, while experimental results on two cool roof methods, cool roof paint and aluminium foil roof, indicated that energy savings proved to be negligible. Incorporating insulation materials via sandwich panels in buildings can substantially enhance energy efficiency in Kuwait and Australia, with observed reductions of 35.7% and 43.8% compared to autoclaved aerated concrete blocks from simulation results. However, in tropical climate of Kodaikanal, India, energy consumption were increased dramatically by 126.2% when sandwich panels were used. This study offers valuable insights into optimal wall materials and energy-saving strategies, such as cool roof methods, insulation and Bio-PCM, for use in various hot climates.

Evaluation of the thermal conductivity and transmittance coefficient of earthen constructive elements

The aim of this work is to determine the thermal conductivity of different earthen constructive elements produced with materials typical of the central-eastern part of the Province of Santa Fe (Argentina), and to evaluate their suitability to be used in the construction of envelopes that comply with the thermal insulation requirements of the corresponding National Regulations. For this purpose, test specimens were made following the different earth construction techniques used in the region (compressed earth block, adobe, rammed earth (tapia), wattle and daub (quincha), and plaster), and their thermal conductivity coefficient was measured, with which the thermal transmittance of different earth construction packages was calculated. The results obtained indicate that the earth construction techniques evaluated show, in all cases, a better thermal performance than traditional solid ceramic brick or concrete block walls, with wattle and daub being the technique with the highest thermal insulation capacity.

THERMAL PERFORMANCE OF DIFFERENT BUILDING TYPOLOGIES IN THIMPHU

The building sector in Bhutan is responsible for 42% of total energy and consumes 242,916 TOE of thermal energy. The maximum thermal energy was used for space heating. As per the studies conducted on the energy efficiency of the buildings in Bhutan, the buildings are found to be the worst performance in terms of thermal and airtightness. Without the proper insulation, lack of choice of the building materials as per the climatic conditions and lacks of awareness in the society about the green building practices has led to poor indoor quality of life. Buildings located inthe high region are found to be uncomfortably cold during winter months.This research focuses on studying the thermal performance of different building typologies. The main findings of this research were on enhancing indoor thermal comfort and reducing heating energy demand by the incorporation of passive measures. The results were achieved by simulating the buildings in EnergyPlus software using the data collected from questionnaires and field surveys. The simulation results showed that among the investigated buildings, a concrete hollow block wall located at Kabesa has the less comfort hour of 15% at the existing condition. When passive interventions were incorporated into the building, the thermal comfort hours were achievable up to 32% with the load reduction potential of 65%.As for the traditional house with the adobe brick wall and timber wall at Changdagang, had more comfort hours than the building located at Kabesa. With the different set of passive intervention, it was found that comfort hour of 38% to 41% and load reduction of 25.9% can be achieved for the building with adobe brick wall and timber wall respectively. Whereas for stone masonry with cement mortar and RCC framed structure located at Begana and Langdru had a thermal comfort hour of more that 30%. However, RCC framed structure was reported to have huge demand for heating energy compared to stone masonry with cement mortar. The passive intervention prepared for RCC and stone masonry had the potential to achieve 41%-57% of thermal comfort hours. The results from all the investigated buildings revealed that the inclusion of passive design could improve indoor thermal comfort and can achieve a reduction in heating energy demand.

Experimental investigation on performance of sandwich wall infill in framed structure

The sandwich wall infill in framed structures is a layered structural system made of thermally insulated core material (EPS layer) with concrete layers on either side reinforced to act monolithically. It is the best replacement for concrete, brick, and hollow block walls because of its low self-weight, few connection joints, and easy and fast installation on site. It also has good thermal and noise insulation properties, a better load-carrying capacity, and was found to be cost-effective. This layered system is resistant to alternate cycles of heat and cold, with less penetration from destructive rays and external forces. For this experimental study, sandwich wall panel specimens (0.75 × 0.75 × 0.1 m) are cast with an external layer of concrete and an Expanded Polystyrene layer as a core, varying its thickness (25 mm, 50 mm, 75 mm), and these layers are bonded together by adequate steel reinforcement. A wall is tested to evaluate its structural performance in the context of ultimate strength capacity, load–deflection profiles, cracking patterns, and failure modalities compared with the conventional wall system. The wall specimen with a minimum core thickness of 25 mm has a maximum load carrying capacity of 504 kN, which attains 98.6% of the ultimate load of a conventional wall specimen, and it also possesses very little deflection of 0.37 mm in the front side of the panel. The maximum strains observed in the concrete layer and reinforced steel bar are 0.0012 and 0.0024, respectively. The current study demonstrates that lightweight sandwich wall panels are a superior replacement for traditional wall systems.

Computational modelling in a high rise building with different building envelope materials for sustainable living

This research focuses on identifying a sustainable material for building envelope for energy efficacy in naturally ventilated high rise residential buildings through CFD. Convective heat transfer is observed in three levels of the 14 storied highrise naturally ventilated building using three different building envelope materials ? burnt clay bricks, solid concrete block, and hollow concrete block. To artificially create the environment with CFD the different temperatures and velocities are used. The boundary conditions - initial outdoor temperatures 30 ?C and 23 ?C, respectively, were kept constant and the initial outdoor velocities 1 m/s to 10 m/s, were varied and simulated at 12 noon condition. Simulation results reveal, higher indoor temperatures in the roof exposed floor. At 30?C it is observed that there is a 0.2-0.3?C temperature difference between the burnt clay brick wall and the hollow concrete block wall through the varied velocities. In all cases of air velocities, the air temperature in the indoor spaces of the solid concrete block wall was found to be highest. This proves that solid concrete block wall has the highest conductivity and least resistivity over the other two materials. In the hollow concrete block, the process of conduction is slow and apparently the temperature in the indoor spaces is reduced. Thus, the results clearly indicate that the temperature in the indoor spaces of the hollow block building envelope was comparatively low when compared to the other two building materials.

Improving thermal comfort of residential building based on Recycling materials in arid and hot regions. Case studies of South of Algeria

the building envelope can reduce heating and cooling consumption, if it is well thermally insulated from the outside. To do this, it is necessary to use eco-friendly materials, such as recycled materials, which could control the environmental impact. The objective of this work is not only to design sustainable designs for hot and arid climates, but also to have new thermal insulation systems based on recycled materials and fibers. In this regard, the systems studied were fixed to a simple concrete block wall, under cladding (dry process). The results showed the important role of insulation with recycled materials such as wood fiber from the outside. These results make it possible to evaluate the potential impact of ETIs based on recycled and natural materials in extreme conditions, highlighting the interest in maintaining summer comfort. It�s concluded that the use of recycled material can be enable to improving consumption energy. Also, the technical-economic analysis can be revealed, the technical feasibility of the systems studied and the economic impact of natural and recycled insulating materials compared to conventional polystyrene insulation.

Energy Conservation and Thermal Insulation Performance of Concrete Block Walls Incorporating Expanded Polystyrene Panels: Experimental and Simulation Study

Energy Conservation and Thermal Insulation Performance of Concrete Block Walls Incorporating Expanded Polystyrene Panels: Experimental and Simulation Study

Grassholme Reservoir: northern embankment stabilisation works

Grassholme Reservoir is a large impounding reservoir commissioned in 1914 in the Lunedale Valley of County Durham. The most recent statutory inspection in 2016 resulted in a ‘Measures in the Interests of Safety’ (MIOS) recommendation to investigate and rectify a suspected unstable embankment slope between the reservoir and an adjacent watercourse. In November 2021, the stability works were completed to the satisfaction of the qualified civil engineer and the MIOS recommendation discharged. A total of around 20 000 m3 of selected clay fill was used to construct a reinforced earth slope with an interlocking concrete block wall at the toe. As a consequence of stabilising the northern embankment, the adjacent Carl Beck has been diverted through a buried pipe until realignment in spring 2022. The aim of this paper is to summarise and illustrate the various complexities associated with stabilising the northern embankment and realigning the existing watercourse, such as mitigating the loss of ancient woodland, managing complex ecological constraints and mitigating land access delays from the offset.

Feasibility experiments of seismic concrete block walls without joint mortar

The authors developed two types of block systems consisting only of main block and key block without joint mortar in consideration of seismic performance and workability. Two types of block systems have different key block shapes: One is the peanuts shape and the other is the dumbbell shape. In this study, the proposed two types of block walls as well as a typical block wall were experimentally investigated to evaluate the seismic performance. In the tests, full-scale, single-story specimens were tested under static cyclic in-plane loading, and failure patterns and cracks were carefully observed. In this paper, the loading bearing capacity, energy dissipation capacity and reuse ratio of block walls are discussed in detail. As a result, the deformability, energy absorption capacity and reuse ratio of the proposed block systems were considerably higher than those of typical block system.

COLLABORATIVE INITIATIVES IMPROVING TSUNAMI EVACUATION ROUTE SAFETY WITH CONCRETE BLOCK WALLS

地域の安全な津波避難路確保を目的に，南海トラフ巨大地震により最大震度7，最大津波高10mが想定されている徳島県南沿岸の2地区で，行政，地域住民，教育機関，専門家，非営利団体等が協働でブロック塀対策に取り組んだ．ブロック塀の点検調査と併せて，塀所有者に意識調査と啓発活動を行うことで，塀の撤去・改修に必要な課題把握に加え，2件のブロック塀の撤去・改修をすることができた．また，ブロック塀の倒壊を考慮した津波避難地図の作成と併せて，ブロック塀の撤去・改修に向けたケースマネジメントの検討を行うことで，個々の課題と対策の方向性を明らかにすることができた．

Thermal insulation of mud bricks made with walnut shells: Characterization and simulation study

This work aims to study the thermal performance of a new bio-composite (clay-walnut shell). Firstly, a geotechnical analysis was carried out on the soil. Different percentage additions: 0, 10, and 20% by weight (wt.%) of walnut shells were adopted to evaluate the thermal impact of WS on unfired clay bricks. Then, the thermophysical properties of produced bio-composites were compared with those of clay alone. The thermal transport properties were measured using the hot disk method. Geotechnical analysis showed that the base material (soil extracted from Nador city; eastern Morocco) has a high clay fraction of 51.8 % and moderate plasticity. Thermal analysis showed that WS improves the thermal insulation of mud bricks while reducing the density. Introducing 20 wt% WS decreased the thermal conductivity of clay by 45.22%, resulting in an increase in thermal resistance. Finally, a comparative study on the dynamic thermal behavior of two types of walls (concrete block wall and clay brick wall − 20 % by weight of walnut shells).The numerical findings revealed that the use of the developed composites increased the energy performance of residential buildings allowing respective savings (10.8% − 7.94%) of energy for heating and cooling needs, motivating the proposal to use WS as a new aggregate for construction.

Experimental studies on blast performance of unreinforced masonry walls of clay bricks and concrete blocks: a state-of-the-art review

Experimental studies on blast performance of unreinforced masonry walls of clay bricks and concrete blocks: a state-of-the-art review

Exploring the thermal behaviour of building materials: Terracotta, concrete hollow block and hollow brick, under the arid climate, case study of Biskra-Algeria

Over time, the need for acceptable indoor thermal environment is inevitable, this need become more alluded in spaces that staying indoor is remarkably more than others (e.g. residential buildings). Also, saving natural resources through adapting the appropriate materials in buildings’ envelopes is an important up-to-date issue. The purpose of this paper is to explore the thermal behaviour of different houses’ envelopes of several materials (terracotta, hollow concrete block and hollow brick walls). In order to understand their performance, three different cases study in Biskra (South of Algeria) have been analysed through in-situ measurements of: outdoor air temperature, external and internal wall radiant temperature. The results show that the terracotta wall has a good thermal behaviour compared to the other walls in term of providing constant and reduced values between external and internal surfaces. This study can be useful for further investigations of classifying materials according to their thermal behaviour and encouraging the use of local materials in hot-dry regions.

Study on seismic performance of red brick walls vs. Autoclaved Aerated concrete block walls

Bricks are usually the building blocks of a structure’s wall. In India, the construction of buildings using red bricks is commonly practised, which causes a heavy load on the structure, leading to seismic failure. The popularity of red bricks is because of its durability, low-cost, convenience and feasibility, however, due to the growing needs, the demand for red bricks has been increased rapidly. To match this demand, Fertile lands are to be sacrificed which it cannot be done on large scales. To add on, the demand for skilled labour and the cost of fuel for klin also increases, these all factors together makes the red bricks costlier. Alternatives for bricks were researched, which This lead to Autoclaved Aerated Concrete (AAC),The lightweight rigid materials present in the AAC blocks reduce the self-weight of the building structure. AAC blocks are eco-friendly, lightweight, and all-weather construction materials that are designed to offer superior performance and durability. They are almost equivalent to, nine times the size of traditional red brick and also these provide better compressive strength. Out of all the labour demand is very minimal and workability is very high. so here we compare the analysis of the seismic performance of Red brick walls VS Autoclaved Aerated Concrete block walls. Here we considered an apartment building of G + 5 storeys in seismic zone III (Chennai). The impact of AAC blocks on seismic responses of RC framed structures is analysed by using the ETABS software. The primary goal is to compare the results of Storey displacement in both axis, Maximum base shear and storey drift under the seismic conditions and how AAC blocks are adequate when compared to conventional red bricks.

The RC samples with infill walls strengthened with steel truss wires

Infilled walls are frequently used to create interior spaces in the reinforced concrete (RC) buildings and to provide heat and sound insulation. However, under earthquake loads, the infill walls resist the load and displacement demands that occur in and out-of-plane. Severe damages of masonry infill walls in many the reinforced concrete frames have been observed after the 2011 Turkey/Van-Ercis earthquake. It is aimed to strengthen the horizontal and vertical joints of the infill walls in order to increase the contribution of the infill wall to RC frame and to restrict the out-of-plane movement of the walls caused by the earthquake in the buildings. In this study, five RC frames used in the experimental works have been produced with various structural defects, 1/5 scale, two-story and one-bay. Two of these RC frames were filled with autoclaved aerated concrete blocks and brick wall. Other two samples were strengthened by adding truss elements to horizontal joints of infill walls. In order to determine the seismic contribution of these strengthening works, reference sample was tested as bare frame. All test samples were tested under reverse cyclic lateral loading and constant vertical loading. For the strengthened and non-strengthened samples with infill walls, the main damage occurred in the infill walls of the 1st storey at the experimental study. As a result, the sample with strengthened infill brick wall, and autoclaved aerated concrete block wall showed a significant increase in the lateral load-carrying capacities, initial stiffness, and the cumulative energy consumption capacity at the end of test.