Cellular Concrete Blocks Research Articles

Seismic Performance of Cellular Lightweight Concrete Block Panels as Infilled Wall in RC Frames Due to Cyclic Lateral Loading

Seismic Performance of Cellular Lightweight Concrete Block Panels as Infilled Wall in RC Frames Due to Cyclic Lateral Loading

Thermo-mechanical Stability Analysis of Hollow Cellular Concrete Block Air Convection Embankments for Cold Regions

Crushed-rock air convection embankment (ACE), as a highly open-graded porous medium, has been used to mitigate the thaw settlement of pavement structures in permafrost regions. Previous studies have revealed that cellular concrete has significant potential as a cost-effective material for ACE to solve the problem of crushed rock shortage in interior Alaska and improved the thermal stability of pavement structures in cold climates. The design configurations of the hollow cellular concrete block ACE were further designed to maximize the performance benefits and facilitate future implementation and field construction. However, the mechanical behaviors of the proposed structures and ice-rich subgrade were still unknown. In this study, a thermo-mechanical coupling model was developed to evaluate the thermal effect on the long-term mechanical stability of the selected pavement structures and subgrade soils. The results indicated that the thermal stability of the proposed hollow cellular concrete block ACEs was superior to that of the conventional crushed-rock ACE. The maximum thaw settlement of the proposed hollow cellular concrete block ACE was only 13.4% that of the conventional crushed-rock ACE. Thermal and mechanical analyses showed that the proposed cellular concrete ACEs have a significant advantage over conventional crushed-rock ACE.

Improving the lateral load resistance capacity of cellular lightweight concrete (CLC) block masonry walls through ferrocement overlay

Cellular lightweight concrete (CLC) block masonry is an eco-friendly building material gaining popularity in both developed and developing countries. Despite its increasing use, the material's behavior under seismic loading remains insufficiently understood. This research involved quasi-static testing of two full-scale CLC blocks masonry walls strengthened with ferrocement overlay. One of the strengthened walls was subjected to confinement, while the other was unconfined. The aim was to assess their seismic performance by comparing force deformation curves, damping, stiffness degradation, and structural performance levels with non-strengthened walls. The findings indicate that the strengthened masonry outperformed the unreinforced version, suggesting that CLC block masonry exhibits potential for effective performance in low to moderate seismic zones.

Lattice concrete: 3D printed periodic cellular structures through selective cement hydration

3D printing of concrete allows fabrication of complex shapes and structures. Among various 3D printing approaches, the particle bed 3D printing technique has gained attention in recent years, especially for its ability to generate complex topologies that are otherwise impossible to make using cement-paste extrusion-based techniques. In this work, we present our trials on 3D printing cellular lattice concrete structures using a powder bed technique by employing selective cement hydration. Specifically, we print two-types of cellular concrete blocks (i) with interconnected spherical voids and (ii) with gyroid structures, each block with uniform edge lengths of 15 cm. We use Ordinary Portland Cement, fine-grained sand, and normal water, without the use of any admixtures or additives. The printing technology used was custom-made and is quite simple and inexpensive involving a syringe based water jetting on to a powder bed of cement and sand mixture. We discuss the quality of the printed specimens obtained as well as their strength characteristics. An inadvertent observation was made, where a compressive strength gain by a factor of more than 2 was obtained in specimens that were exposed to open atmosphere for a long duration after a 28 day curing period compared to those that were tested immediately after curing. The current study demonstrates the feasibility of fabricating cellular lattice concrete structures that can potentially be useful as programmable metamaterials for civil engineering applications.

Қоршау құрылымдарындағы жылу өткізгіш қосындылары

In order to reduce the heat loss of a building and meet the requirements of regulations, multi-storey building envelopes have been widely used in construction in recent years, including the placement of a thermal insulation layer inside the structure. Under the influence of economic considerations, one of the main types of building floors was a masonry cellular concrete block faced with brick with effective insulation between floors. Considering the modernization of existing types of building envelopes and the appearance of a large number of new structures, the question arose about the correct determination of the thermal properties (mainly thermal protection) of such structures. Temperatures are evenly distributed because the heat dissipated over the surface of the structure helps to balance their values when looking at the room. However, the length of the temperature field distortion region increases (due to the presence of interference). On the contrary, the temperature decrease (which extends over a short length of the enclosure) becomes more prominent and noticeable due to inclusions and inclusions located on the warm surface of the structure. Such peculiarities of temperature distribution in the zone of heat conducting inclusions of different types are confirmed by the experience of operation of buildings with corresponding design solutions for panel walls. If the walls at the joints of panels are covered with a thermally conductive protective and finishing layer on the warm side, the temperature distribution over the inner surface of the wall will be uniform; if there is not enough thermal conductive inclusions and inclusions located on the warm surface of the wall, the temperature distribution will be uniform.

ОЦЕНКА МОРОЗОСТОЙКОСТИ КЛАДОЧНЫХ СТЕНОВЫХ ИЗДЕЛИЙ С УЧЕТОМ МЕТОДИКИ ВЛАГОНАСЫЩЕНИЯ В РОССИЙСКИХ НОРМАХ И СТАНДАРТАХ.

In order to improve the Russian codes in the field of brick and masonry structures, a comparative analysis of frost resistance assessment of masonry wall products of wide application in construction practice was carried out. The Russian codes revealed inconsistencies in the assessment of frost resistance of masonry products. In particular, in SP 15.13330.2020 [2] and GOST 7025-91 [4] one index F for determining the frost resistance of ceramic, silicate products, as well as the frost resistance of concrete, expanded clay and cellular concrete blocks, which misleads consumers and designers. In order to eliminate the noted inaccuracies, the article gives proposals for adjustments to SP 15.13330 and GOST 7025.

Formation of Cellular Concrete Structures Based on Waste Glass and Liquid Glass

The use of waste in the production of building materials is one of the possible ways to solve problems related to the sustainable management of non-degradable waste and difficult-to-recycle secondary resources. In this paper, a method is proposed for the non-autoclave production of an ultra-lightweight cellular concrete based on Portland cement, glass waste and liquid glass. A mixture of sodium hexafluorosilicate and hydroxide is used as a hardening activator, an aluminum powder serves as a gas-forming agent. The setting and hardening of raw mixtures occurs under the action of exothermal heat release due to a complex of chemical reactions occurring in the system, and the resulting material does not require additional heat treatment. It is optimal to use two fractions of glass waste to achieve acceptable material strength: coarse crushed (fineness modulus Fm = 0.945) and finely ground (specific surface Ssp = 450–550 m2/kg) glass. Glass particles of the fine fraction of glass, along with Portland cement, participate in hydrolytic and structure-forming processes, while glass particles of the coarse fraction play the role of reinforcing filler. The influence of the dispersion of glass and the density of liquid glass on the density, porosity, strength, water absorption and water resistance of the resulting cellular material was determined. At an average density of cellular concrete in the dry state of 150–320 kg/m3, the following characteristics can be achieved: a compressive strength up to 2.0 MPa, bending strength up to 0.38 MPa, thermal conductivity coefficient of the material in the range 0.05–0.09 W/(K·m), and a maximum operating temperature of 800 °C. The proposed ultra-lightweight cellular concrete can be used as a non-combustible heat and sound insulation material, as well as a repairing composition; the cellular concrete blocks can be used as filling masonry and for the construction of non-bearing internal walls.

Seismic performance evaluation of plastered cellular lightweight concrete (CLC) block masonry walls

The current research presents a novel and sustainable load-bearing system utilizing cellular lightweight concrete block masonry walls. These blocks, known for their eco-friendly properties and increasing popularity in the construction industry, have been studied extensively for their physical and mechanical characteristics. However, this study aims to expand upon previous research by examining the seismic performance of these walls in a seismically active region, where cellular lightweight concrete block usage is emerging. The study includes the construction and testing of multiple masonry prisms, wallets, and full-scale walls using a quasi-static reverse cyclic loading protocol. The behavior of the walls is analyzed and compared in terms of various parameters such as force–deformation curve, energy dissipation, stiffness degradation, deformation ductility factor, response modification factor, and seismic performance levels, as well as rocking, in-plane sliding, and out-of-plane movement. The results indicate that the use of confining elements significantly improves the lateral load capacity, elastic stiffness, and displacement ductility factor of the confined masonry wall in comparison to an unreinforced masonry wall by 102%, 66.67%, and 5.3%, respectively. Overall, the study concludes that the inclusion of confining elements enhances the seismic performance of the confined masonry wall under lateral loading.

The effect of polyurethane foam glue on the strength and deformability of aerated concrete masonry when using it as a masonry mortar

The article presents the results of experimental studies of masonry made of cellular concrete blocks of autoclave hardening YTONG produced by JSC «Kcell-Aeroblock-Center» on the adhesive composition (polyurethane glue) Dryfix (POLYPAG AG). The tests included comprehensive studies of the strength and deformability of masonry walls made of cellular concrete blocks, under various types of stress state of structures: central and off-center compression of masonry walls, axial tension on bandaged and unbound seams, tensile bending on bandaged and unbound seams, shear with an assessment of tangential adhesion. Tests have confirmed the inconsistency of the technology of laying blocks of cellular concrete on the adhesive composition of Dryfix with incomplete filling of seams. This technology has a significant impact on the strength of the masonry during bending: the adhesion of the blocks to each other with such an adhesive composition applied to the surface of the block is significantly lower than the value obtained when testing the blocks for axial tension. According to the results of the experiments, the value of the temporary resistance to axial stretching along the unbound section (normal adhesion) of the masonry, the values of the calculated resistance of the masonry to stretching during bending along the unbound and tied sections, as well as the value of the calculated resistance of the masonry under central compression were determined.

Influence of Reinforcing Composite Mesh on the Strength of Walls Made of Cellular Concrete Blocks under the Action of Static and Dynamic Loads

Influence of Reinforcing Composite Mesh on the Strength of Walls Made of Cellular Concrete Blocks under the Action of Static and Dynamic Loads

The influence of anhydrite III as cement replacement material in production of lightweight masonry blocks for unreinforced non-load bearing walls

Lightweight cellular hollow concrete (LCHC) block is a type of masonry unit that has excellent thermal and acoustic performance, fire resistance and high weathering resistance, and manufactured by precast technique. This work presents an experimental study, which investigates the effects of volumetric partial replacement of Portland cement by calcium sulfate anhydrite on precast properties, especially hardening time of the products, thermal insulation properties and mechanical properties of the blocks. LCHC block is produced by the mixing of Portland cement (PC), anhydrite III (ANH), expanded perlite (EP), pumice (PU) and calcite (CA) for building applications. The physical and mechanical properties of LCHC blocks having various replacement levels of ANH are studied. Experimental studies were carried out on both 10x10x10 cm3 cube specimens and 19x19x39 cm3 block specimens. In this research work, LCHC blocks with 16 different mixture batches were cast into a mould with vibro-compacting, de-moulded immediately and transferred to a storage area for curing up to 28 days in normal air condition. The unit weights and compressive strengths of the cube specimens decreased as the ANH replacement level increased, depending on the decrease in the cement ratio. However, it was observed that the compressive strength of the block specimens increased up to the volumetric replacement level of 1.86 %. As expected, the thermal conductivity values of the specimens decreased with the decrease in unit weight. The most notable change on the specimens occurred in the hardening time. The hardening process of the specimens can be completed up to 90 times faster than the control mixture. In addition, within the scope of the study, three formulations are presented in which the compressive strength and the elastic modulus of the wall sections made with LCHC blocks can be calculated, and thermal conductivity value of masonry block unit can be calculated.

Thermal performance analysis of hollow cellular concrete block air convection embankment for cold regions

Crushed-rock air convection embankment (ACE) is an excellent passive cooling technique that uses open-graded crushed rocks as a “thermal semi-conductor” to prevent roadbeds from thawing in summer and enhance the cooling effect in winter in permafrost regions. However, the desired crushed rocks needed for ACE are not readily available in interior Alaska, resulting in extremely high construction costs. Previous studies indicated that using the cost-effective cellular concrete for ACE could effectively enhance the cooling performance of ACE and mitigate moisture warping and temperature curling of the asphalt concrete layer. It is promising to be an alternative to crushed rocks for ACE to mitigate pavement distresses. However, the design of cellular concrete ACE needs to be further studied to maximize performance and facilitate future implementation. Hence, two design configurations of cellular concrete block ACEs were proposed in this study. The thermal performance of pavement structures with these two designs was investigated by comparing them with the other four. A total of six pavement structures were analyzed, including a typical flexible pavement in the Northern Region of Alaska and five pavement structures reinforced with different paving interlayers, i.e., silty sand/gravel, crushed rocks, cast-in-place cellular concrete (full insulation), and two types of precast cellular concrete blocks. The thermal profiles, air pressure gradients, and velocities were numerically analyzed in ANSYS Fluent. The numerical results indicated that the two proposed cellular concrete ACEs exhibited a significant heat insulation effect in summer and a desired cooling effect in winter, which raised the permafrost table significantly. The maximum thaw depth of the two proposed cellular concrete ACEs was only 15% of the thaw depth of traditional silty sand/gravel embankment.

Obtaining Portland Cement From Coal Ash Alay Deposit

In this article, the temperature regime and the amount of heat required for sintering a mixture obtained by burning coal with the addition of natural clay are investigated. The chemical composition of ash and natural clay, which are suitable for use as raw materials for the production of Portland cement and other building materials, has been studied. As a component for the manufacture of heavy, lightweight cellular concrete blocks, mortars and dry mortars. The chemical composition and quantitative content of substances was determined by the complexometric (volumetric) method.

The effect of silica fume admixture on the compressive strength of the cellular lightweight concrete

Foam concrete has practical and economic advantages in construction, including reducing the structure's weight by building foundations. The market demand for foam concrete such as Cellular Lightweight Concrete (CLC) block has increased recently. One way to reduce the density of CLC is to add air pores to the cement paste or mortar mixture. However, the addition of pores can reduce the strength of lightweight bricks. Therefore, there is a need for innovation to improve the quality of CLC block by replacing some of the cement with other added materials. This study aims to obtain a good quality CLC block using silica fume to replace partial cement in a mortar mixture. The specimens are a CLC block measuring 10 cm wide, 20 cm high and 60 cm long. Variation of mortar mixture using silica fume percentage of 0%, 0.5%, 1%, 5%, 10% and 15% of cement weight. The output data generated from this sample are compressive strength, displacement, stress, strain and the modulus of elasticity. The test results obtained the optimum CLC compressive strength of 1.03 MPa at 10% silica fume composition. This optimum compressive strength of CLC was simulated using the LUSAS finite element analysis to obtain the displacement and stress-strain patterns. Based on the LUSAS numerical analysis, the optimum compressive strength of the CLC block was 1.06 MPa. This study shows that adding 10% silica to the CLC mortar mixture can increase the compressive strength by 81.25% compared to mortar without silica fume.

EXPERIMENTAL INVESTIGATION ON CELLULAR LIGHT WEIGHT CONCRETE BLOCK USING IRONITE POWDER FOR REPLACEMENT OF CEMENT

In recent years, with expanding urbanization and increasing demand for construction materials, brick kilns have to grow to meet the demand. It has directly or indirectly caused a series of environmental and health problems. Cellular Light Weight Technology blocks can be used as an alternative to the red bricks, to reduce Environmental pollution and Global warming. CLC blocks are environment friendly. The energy consumed in the production of CLC blocks is only a fraction compared to the production of red bricks and emits no pollutants and creates no toxic products or by products. cellular concrete blocks are concrete blocks having homogeneous, uniformly distributed and stable void or air cells. The cell structure is attained with the addition of preformed stable foam in the concrete mix. These blocks are light weight, eco-friendly, economical and better alternative to conventional burnt clay bricks and cement concrete blocks in the modern building industry. This paper presents an experimental study carried out on bricks made from fly ash. The use of lightweight foamed concrete offer many benefits and advantageous particularly cost saving, fast completion and easy application compared to other materials such as steel and timber. Hence the present investigation was taken up with a view to verify the suitability, feasibility and potential use of ironite powder. The ironite powder has been taken for partial replacement with cement. This investigation also aims to use waste materials effectively since ironite is a waste obtained from metal wastes. The properties of the Cellular blocks are investigated by conducting various tests like Compressive strength test, water absorption test and flexural test. 0%,10%,20%,40% ironite powder, have been added for testing and validation of new form of brick

Variability of Mechanical Properties of Cellular Lightweight Concrete Infill and Its Effect on Seismic Safety

Cellular lightweight concrete (CLC) block masonry has gained popularity in the masonry market with the growing demand in the modern construction industry due to its various advantages, including a positive impact on the environment. Subsequently, the detailed characterization of its vital engineering properties should be studied for the development of the mathematical model, analysis, evaluation, and design of structures made of CLC block masonry. The present study investigates the variability in two important strength properties of CLC block masonry and proposes the most appropriate models for their statistical distribution to support probability-based structural analysis and design. This study shows that the assumption of a normal distribution in the absence of an appropriate uncertainty model can result in an inaccurate estimate of the seismic risk of an RC frame building infilled with CLC block masonry. The paper further assesses the seismic safety of a typical RC framed building infilled with CLC block masonry in relation to traditional brick masonry, considering the proposed uncertainty model. Although CLC block masonry results in a higher seismic risk compared with traditional brick masonry, it can be used as an infill material in high seismic areas because it results in a probability of failure within the acceptable limit.

Properties of polypropylene fiber reinforced cellular lightweight high calcium fly ash geopolymer mortar

In this study, fly ash (FA) was used as a starting material to develop an environmentally friendly polypropylene fiber (PPF) reinforced cellular lightweight high calcium fly ash geopolymer mortar (PPF-CLFAG). The high calcium FA, a by-product of coal based electrical power plant from Mae Moh, Thailand, was used as the starting material. The PPF contents of 0%, 0.5%, 1%, 1.5%, 2%, 2.5%, and 3% by weight of FA, NaOH at concentrations of 2, 4, 6, and 8 molars, and foam contents (Fc) of 0%, 1%, and 2% of total weight were tested. The unit weight, compressive strength, flexural strength, and scanning electron microscope imaging were tested at the age of 7 days. The dry unit weight was found to decrease with the increasing PPF content and Fc. Whereas, the dry unit weight decreased as NaOH concentrations decreased. The sample with 3%PPF, 2 M NaOH, and 2% Fc had the lowest dry unit weight of 541 kg/m3. The highest compressive strength was obtained with 0.5%PPF content, whereas the highest flexural strength was observed with 2.5%PPF content, regardless of the NaOH concentration and Fc. According to Thailand Industrial Standard (TIS), all mixtures in this study passed the TIS minimum strength requirement for cellular lightweight concrete blocks. The maximum flexural strength of 3.85 MPa and density of 1279 kg/m3 were obtained with the sample with 2.5%PPF and 8 M NaOH with no foam. Empirical equations to predict dry unit weight, compressive strength, and flexural strength of PPF-CLFAG for a given NaOH concentration, PPF content, and Fc were proposed.

Utilization of locally produced waste in the production of sustainable mortar

Environmental pollution due to CO2 emissions from the cement industry and the depletion of the natural resources of the aggregate used in the concrete industry call for the need to find alternatives to reduce these harmful effects. Some of these alternatives include the use of supplementary cementitious materials and the reuse of wastes from other industries as cement and aggregate replacement materials. Thus, this study was conducted to investigate the possibility of using autoclaved aerated (cellular) concrete blocks waste powder (CCP) that is locally produced as a partial substitute for cement or sand in mortar. Seven mixtures were cast. Three of them made by the substitution of the cement with CCP passed from 0.075 mm sieve (5%, 10 % and 15 % by weight), and other three mixtures comprised the replacement of natural sand with CCP of size 0.15−0.075 mm (5%, 10 % and 20 % by weight). A reference mixture (without replacement) was also performed for comparison purposes. The mechanical and water absorption properties were examined. Results indicated that among all tests examined, a sustainable mortar was produced by the substitution of the cement or sand with 10% CCP with an enhancement in the compressive strength without significantly affecting other properties of the mortar.

Lightweight Cellular Hollow Concrete Blocks Containing Volcanic Tuff Powder, Expanded Clay and Diatomite for Non-Load Bearing Walls

Lightweight cellular hollow concrete (LCHC) block is a type of masonry unit manufactured by precast technique. LCHC blocks are produced by the mixing of Portland cement, volcanic tuff, expanded clay and diatomite for building applications. LCHC blocks are lightweight, and the frequent cellular holes provide excellent thermal and acoustic performance, fire resistance and resistance to harsh environmental conditions. In this research work, LCHC blocks with 28 different mix proportions were cast into a mould with vibro-compacting, de-moulded immediately and transferred to a storage area for curing up to 120 days in standard air condition at room temperature. The blocks were designed with 21 cellular spaces of 10 mm width. For each mixture, twenty four block specimens were prepared and tested in the air dry condition for compressive strength and water absorption in accordance with BS 1881: Part 116. This paper initially examines how volcanic tuff powder affects the characteristics of lightweight concrete masonry mixtures and investigates the use of quaternary blends containing volcanic tuff, expanded clay, diatomite and Portland cement to produce LCHC blocks for partitioning walls.

Increasing the Solidity of Masonry Walls Made of Cellular Concrete Blocks of Autoclave Hardening by using Polyurethane Foam Adhesive Composition as a Masonry Solution

The article presents the results of experimental studies of determining the strength of normal adhesion (under axial tension) in the masonry of cellular concrete blocks of autoclave hardening classes for compressive strength B1.5 ÷ B3.5 on various cement solutions and polyurethane foam adhesives. Tests were carried out in the Laboratory of the Department of «Reinforced Concrete and Stone Structures» of Moscow State University of Civil Engineering on experimental samples representing two cubes of 150x150x150 mm in size, sawn out of cellular concrete blocks and bonded (glued) together using masonry (binding) compositions. The analysis of research results was performed and the value of the percentage of increase in normal adhesion in masonry when using polyurethane foam adhesives in masonry joints instead of cement masonry solutions was determined.