Lightweight Concrete Material Research Articles

Cost Effectiveness and SWOT Analysis of Using Conventional or Light-Weight Concrete Materials in Buildings Rested on Weak Soils

Cost Effectiveness and SWOT Analysis of Using Conventional or Light-Weight Concrete Materials in Buildings Rested on Weak Soils

A Assessment of stone ash as a lightweight concrete constituent material with the addition of bestmittel additives

Technological advances in the field of building construction have developed very rapidly, so we need a construction technology that can reduce exploitation of nature. Utilization of stone ash is one of the new material alternatives in concrete mixtures with the addition of the bestmittel additive to accelerate drying in concrete. The purpose of this study is to determine the aggregate characteristics, specific gravity and compressive strength of concrete. The method used is laboratory experimental research with variations in stone ash samples of 5%, 10% and 15% to the weight of sand with the addition of 0.6% bestmittell additive to the weight of cement. The results showed that stone ash and bestmittell additives affect the characteristics of the concrete. The value of specific gravity increases with increasing percentage of stone ash, namely 1898.77 kg/m3 in normal concrete, 1911.35 kg/m3 of 5% stone ash concrete, 1922.34 kg/m3 of 10% stone ash concrete and 1927.06 kg/m3 m3 on 10% stone ash concrete. The compressive strength value of characteristic for the compositions AB 5%, AB 10% and AB 15% are 10.08 Mpa, 10.35 Mpa and 10.88 Mpa respectively, an increase compared to normal AB 0% concrete, namely 9.03 Mpa at 28 days.

Utilization of Plant Waste Materials as a Partial Replacement of Cement and Fine Aggregates in Concrete Production

The research focused on possibility of producing high quality concrete by the way of adding plant waste materials like sugarcane bagasse ash (SBA), rice husk (RH) and cassava starch (CS) to concrete mixtures. Varying percentages of SBA (0, 5, 10, 15% - weight of the cement), rice husk (0, 5, 10, 15% - weight of the fine aggregates) and cassava starch (0, 1, 2, 3% - weight of the cement) were incorporated into the concrete mixtures design. Comprehensive laboratory investigations were done on the concrete’s workability (slump), density and mechanical strength, to establish the impact of these organic materials on the mechanical parameters of the concrete produced. The laboratory test results show that SBA and CS augmented the concrete slump rate whereas, the rice husk retarded the concrete’s workability. The result of the density indicated that the rice husk and SBA reduced the concrete’s density; however, the cassava starch caused substantial increment in the concrete’s density. On the concrete mechanical properties, it was noted from the results that the compressive strength was boosted by the incorporation of SBA and CS. The maximum compressive strength (23.7 N mm-2) was recorded through by substituting the cement with 10 and 2% of SBA and cassava starch respectively, in the presence of 10% RH as partial replacement of the sand. This study findings had revealed the potential of SBA, rice husk and cassava starch combinations in the right mixture design, to produce light-weight concrete material having sustainable high compressive strength.

Physical, Mechanical, and Microstructure Characteristics of Ultra-High-Performance Concrete Containing Lightweight Aggregates.

This study explores and enhances the resistance of an ultra-high-performance concrete (UHPC) to explosive spalling under elevated temperatures. This study investigates the impact of lightweight aggregates (LWAs) on the mechanical and microstructural properties of the UHPC. Various UHPC specimens were created by replacing silica sand with LWAs in percentages ranging from 0% to 30%. The evaluation of these specimens involved assessing their compressive and flexural strengths, density, mass loss, shrinkage, porosity, and microstructural characteristics using scanning electron microscopy (SEM). This study provides valuable insights by analyzing the influence of lightweight aggregates on the strength, durability, and microstructure of UHPC. The results reveal that incorporating LWAs in the UHPC improved its flowability while decreasing its density, as the percentage of LWAs increased from 5% to 30%. Including 30% LWA resulted in a mass loss of 4.8% at 300 °C, which reduced the compressive and flexural strengths across all curing durations. However, the UHPC samples subjected to higher temperatures displayed higher strength than those exposed to ambient conditions. The microstructure analysis demonstrated that the UHPC specimens with 30% LWA exhibited increased density due to continuous hydration from the water in the lightweight aggregate. The pore size distribution graph indicated that incorporating more of the LWA increased porosity, although the returns diminished beyond a certain point. Overall, these findings offer valuable insights into the influence of lightweight aggregates on the physical and strength characteristics of UHPC. This research holds significant implications for developing high-performance, lightweight concrete materials.

Optimization Algorithm of Reinforcement Point Location of New Lightweight Concrete Material for Building Exterior Wall

Abstract Current methods for predicting the location of reinforced concrete materials neglect the precise division of material damage areas, resulting in poor prediction accuracy of the location of reinforced concrete. Therefore, a new optimization algorithm for the location of reinforcing points of new lightweight concrete materials for building exterior walls is proposed. The damage area of lightweight concrete is divided into several zones by using the precise threshold method. Based on the least squares support vector machine, the crack location on the surface of the new lightweight concrete wall is predicted. By solving the coordinates of each point of the triangle, the active reinforcement of the surface cracks of the new lightweight concrete wall materials is realized. The experimental results show that the proposed method takes less time and the prediction accuracy of the reinforced point position of the new lightweight concrete material is higher.

Study on the performance of calcined spent waterglass foundry sand in alkali-activated foam concrete

The resource utilization of spent foundry sand (SFS) helps solve environmental problems and reduce construction costs. Using SFS as fine aggregate incorporated into concrete for practical application has recently become a research hotspot. However, researchers are rarely concerned about the application of SFS in alkali-activated foamed concrete (AAFC). AAFC is a lightweight concrete material with excellent thermal insulation and fire resistance while reducing CO2 emissions. In this paper, spent foundry waterglass sand (SwFS) calcined at 900 °C replaced fine aggregates (0%, 20%, 40%, 60%, 80%, 100%) to prepare AAFC. This paper studied the performance of calcined SwFS in alkali-activated foam concrete. The experimental results show that the SwFS suffered calcined at 900 °C release SiO32− at slow speeds in AAFC and can be an auxiliary activator for AAFC. In addition, the compressive strength of AAFC with SwFS added to 900 °C increased by 15% ∼ 29% and 15% ∼ 25% at 3 d and 7 d, respectively, and decreased slightly at 28 d.

Compressive strength of light-weight concrete material made from treated wood waste as a coarse aggregate

The effect of replacing the conventional coarse aggregate with wood shavings was evaluated relative to the 28-day compressive strength of the concrete. Six groups were studied: group-1 represented the normal concrete (NC-CTRL1), group-2 (TW-CTRL2) comprised the specimens that had the replacement of the coarse aggregate with raw wood shavings, group-3, group-4, group-5, and group 6 represented the specimens that had the coarse aggregate as coated (treated) wood shavings with cement paste (group-3 and -4) and with tile adhesive paste (group-5 and -6), with and without the effect of the emulsifier, respectively. The density of the TW-CTRL2 concrete was 31.4% lighter than NC-CTRL1. However, the compressive strength of TW-CTRL2 was 75% of the NC-CTRL1, but within the acceptable limits stated in ASTM standards. The findings of this study showed a potential to use the produced concrete as concrete masonry unit when compared with the values reported in previous studies. Compared with TW-CTRL2, the compressive strength increased 45% and 20% for the coated wood shavings with cement and tile adhesive pastes, respectively. The effect of using the emulsifier in the coating process of the wood shavings increased the compressive strength by 20%, and reduced the voids of the concrete by 3%.

Experimental and analytical behavior of one-way fiber foamed concrete slabs reinforced with/without glass fiber grid under 4-point flexural test

PurposeThe primary objective of this study is to produce one-way slabs made of LWFC with low density and sufficient compressive strength suitable for structural purpose then investigate their flexural behavior under various types of reinforcement and thickness of the slab and the influence of addition of PP fibers reinforcement on the mechanical behavior of reinforced concrete slabs. The specimens were tested using four-point loading. The results concerning load capacity, deflection and failure mode and crack pattern for each specimen were obtained. Also, an analytical investigation of PP fiber and GFG contribution on the flexural behavior of foamed concrete slabs is studied to investigate the significant role of PP fiber on the stress distribution in reinforced foam concrete and predict the flexural moment capacity.Design/methodology/approachThe materials used in this study are cement, fine aggregate (sand), water, PP fibers, foaming agent, chemical additives if required, steel reinforcing rebars and glass fiber grid. The combination of these constituent materials will be used to produce foamed concrete in this research Then this study will present the experimental program of one-way foamed concrete slabs including slabs reinforced with GFR grids and another with steel reinforcements. The slabs will be tested in the laboratory under static loading conditions to investigate their ultimate capacities. The flexural behavior is to the interest of the slabs reinforced with GFR grids reinforcements in comparison with that of one with steel reinforcing rebars. Three groups are considered. (1) Group I: two slabs of PP fiber foamed concrete with minimum required reinforcements. (2) Group II: two slabs of PP fiber foamed concrete with glass fiber grids. (3) Group III: two slabs of PP fiber foamed concrete with the minimum required reinforcements and glass fiber grids.FindingsThe experimental results proved the effectiveness and efficiency of this the new system in producing a low density of concrete below 1900 kg/m3 had a corresponding strength of about 17 MPa at least. Besides, the presence of PP fibers had a noticeable improvement on the flexural strength values for all the examined slabs. It was found that the specimens reinforced with steel reinforcement mesh carried higher flexural capacity compared to these reinforced with GFG only. The specimens reinforced with GFG exhibited the lowest flexural capacity due to GFG separation from the concrete substrate. Also, an analytical investigation to predict the flexural strength of all tested specimens was carried out. The analytical results were agreed with the experimental results. Therefore, LWFC can be used as a substitute lightweight concrete material for the production of structural concrete applications in the construction industries today.Research limitations/implicationsFoamed concrete is a wide field to discuss. To achieve the objectives of the project, the study is focused on the foamed concrete with the following limitations: (1) because the aim of this research is to produce foamed concrete suitable for structural purposes, it is decided to produce mixes within the density range 1300–1900 kg/m3. (2) Simply-supported slabs are of considered. (3) This study also looks out by using GFR and without it.Originality/valueThe main objectives of this study were producing structural foamed concrete slabs and investigate their flexural response for residential uses.

High value-added resource treatment of antimony tailings: preparation of high-strength lightweight foam concrete materials

The continuous exploitation of global mineral resources leaves ever increasing tailings, which leads to the accumulation of antimony tailings and causes antimony pollution accidents. The complex chemical composition and associated harmful elements of antimony tailings limit their large-scale consumption and high-value comprehensive utilization. To realize the solidification/stabilization of antimony tailings with heavy metals and achieve large-scale high-value utilization, in this paper, high-strength and lightweight concrete materials based on antimony tailing powder were prepared by using antimony tailing powder as the main raw material, and cement clinker, activator, coagulant and foaming agent as the supplements. In this manner, the performance of high-strength and lightweight concrete materials were investigated and optimized in terms of mechanical properties, waterproofing properties, micromorphology, etc. The experiment results show that the decrease of the compressive strength and apparent density of the specimen slurry is due to the increased amount of antimony tailing micronized powder. Additionally, the influence of different foaming agents on the material is significant. With the addition of antimony tailing of 50% and H2O2 of 0.6% into the cementitious material of PC42.5, the material presents optimal high-strength and lightweight performance. Moreover, the compressive strength at 28 d reaches up to 36.2 MPa, and the dry apparent density is as high as 1449.2188 kg/m3. In addition, the optimal system has been optimized in terms of waterproof performance. Softening coefficient of the composite with optimized composition was increased by 55.1%, reaching 0.86, which is sufficiently high for waterproof application.

Thermal Conductivity of Thermally Insulated Concretes in a Nuclear Safety Vessel of Reactor Vault: Experimental Interpretation

Thermally insulated concretes are a type of alternative building material that helps improve thermal efficiency in nuclear reactor vault safety vessel applications. The experimental results of thermal conductivity values of lightweight concrete materials at various temperatures are presented in this paper. To minimize heat conduction in concrete, different lightweight aggregates and vermiculite are employed as coarse aggregate alternatives.Both linear and plane heat source approaches are used to calculate the thermal conductivity values of the specimens. The findings emphasize that increasing the proportion of lightweight particles in concrete may dramatically lower the thermal conductivity, with the kind of lightweight aggregates having a vital role in thermal insulation. The inclusion of micron-sized vermiculite decreases heat conductivity even further; however, the effect is less obvious than that of lightweight particles.

Fire performance of lightweight concrete-filled LSF wall panels

Light Gauge Steel Frame (LSF) wall panels with cold-formed thin-walled steel-Lipped Channel Sections (LCS) and plasterboard linings are increasingly used in the construction industry due to their lightweight and constructability characteristics. However, due to the high thermal conductivity of the LCS, rapid heat transfer is observed in LSF walls, causing negative impacts to the fire performance of the LSF wall elements. Cavity insulation is one of the practical solutions used in the industry to improve the fire performance of LSF walls. Insulation materials such as rockwool, glass fibre, cellulose fibre, ceramic fibre are commonly used as cavity insulation materials in LSF walls. A novel approach in LSF walls is the introduction of lightweight concrete filling as a cavity filler. The effect of lightweight concrete filling on the fire performance of LSF walls was analysed with the numerical investigation in this study. Fire performance of conventional LSF walls with 12.5 mm and 15 mm single and double plasterboard with Autoclaved Aerated Concrete (AAC) with 600 kg/m3 density, Foam Concrete (FC) with 650 kg/m3 density and FC with 1000 kg/m3 density lightweight concrete fillings were compared with LSF walls without cavity insulation and rockwool insulation under standard and hydrocarbon fire conditions. It was observed promising improvement in insulation and load-bearing fire ratings in LSF walls with lightweight concrete filling. Among lightweight concrete materials considered, FC with 1000 kg/m3 density has exhibited the best fire performance. LSF walls performance could be enhanced with lightweight concrete fillings depending on the application with improved fire performance.

A numerical study of the comparison of normal concrete and light weight concrete exterior beamcolumn joints behavior to cyclic lateral loads

This paper presents a numerical analysis of the exterior Beam-Column Joints (BCJ) in resisting a combination of constant axial and lateral cyclic loads. The materials used in this study were Normal Concrete (NC) and Light Weight Concrete (LWC). Light Weight Concrete has been commonly used to reduce the mass of buildings and minimize the structural damages due to earthquakes. A numerical model of exterior BCJ using NC materials was verified using experimental data from the previous research. Then, these models of exterior BCJ using NC and LWC materials were analyzed to obtain the performance. This study aimed to elaborate on the LWC as materials of structures to resist earthquake loads. The performance of the exterior BCJ models was analyzed through hysteretic curves, ductility, stiffness degradation, and strength degradation. The analysis results showed that the NC-BCJ model achieved a higher maximum story drift of 5.3% than the LWC-BCJ model of 4.5%. NC-BCJ model reached higher maximum lateral forces of 40.58 kN and 40.51 kN under push and pull loads, compared with the LWC-BCJ model of 27.83 kN and 32.40 kN. The exterior NC-BCJ model satisfied the strength criteria in the ACI 374.1-19 with a ratio of 1.0 under push and pull loads. Despite the lower maximum lateral forces achieved by the LWC-BCJ model than NC-BCJ, it satisfied this criterion with ratios of 0.93 and 0.99 under push and pull loads, respectively. Both NC-BCJ and LWC-BCJ models performed moderate ductility of 2.70 and 2.52.

Lightweight concrete as covers on floating house platforms made from expanded polystyrene system (EPS) material

Floating houses can be utilized in coastal areas as they are equipped with platforms made from expanded polystyrene system (styrofoam) and lightweight concrete covers. A lightweight concrete cover on a floating house platform made from styrofoam can improve the feasibility of housing in terms of strength, comfort and cleanliness. This research aims to obtain mixture that meet the weight and compressive strength requirements of lightweight concrete and produce them as covers on floating houses platform. The compositions of lightweight concrete materials in this research use volume ratios of 1 Pc: 2 Sand: 3 Styrofoam, 1 Pc: 1.5 Sand: 2.5 Styrofoam and 1 Pc: 1.25 Sand: 2.75 Styrofoam. The research results show that the concrete made with styrofoam qualifies as lightweight concrete with average volume weight of concrete produced between 1000-1300 kg/m3. The lightest concrete weight (1097.88 kg/m3) could be obtained from variations of mixture of 1 Pc: 1.25 Sand: 2.75 Styrofoam, The highest concrete compressive strength results were obtained from the mixture of 1 Pc: 2 Sand: 3 Styrofoam (119.26 kg/cm2). The variations of concrete mixture of 1 Pc: 2 Sand: 3 Styrofoam can be considered as lightweight concrete (≤ 1900 kg/m3).

Experimental Study of Beeswax / Rice Husk Ash Phase Changes Material as Energy Storage in Concrete

Buildings with lightweight concrete are currently used as a solution for mass housing construction which is relatively cheaper, although it does not provide indoor thermal comfort due to the use of this building material. Lightweight concrete building materials are able to store heat for a long time, so that at night the heat is released indoors. The combination of building materials and PCM is an efficient way to increase the storage capacity of thermal energy in building components. The purpose of this study was to determine the compressive strength of the concrete if the coarse aggregate (gravel) was replaced by part of the gravel material using the Phase Change Material of beeswax (beeswax) according to the required percentage starting from 0%, 5%, 10%, 15% and if the aggregate was fine. (Sand) is partially replaced aby using Rice husk ash with various variations starting from 0%, 5%, 10%, 15%. In addition, this utilization is a good alternative, because there will be a process of utilizing rice husk ash which was previously wasted while these items can be used or processed into additives to the concrete mixture.

Experimental Study of Beeswax / Rice Husk Ash Phase Changes Material as Energy Storage in Concrete

Buildings with lightweight concrete are currently used as a solution for mass housing construction which is relatively cheaper, although it does not provide indoor thermal comfort due to the use of this building material. Lightweight concrete building materials are able to store heat for a long time, so that at night the heat is released indoors. The combination of building materials and PCM is an efficient way to increase the storage capacity of thermal energy in building components. The purpose of this study was to determine the compressive strength of the concrete if the coarse aggregate (gravel) was replaced by part of the gravel material using the Phase Change Material of beeswax (beeswax) according to the required percentage starting from 0%, 5%, 10%, 15% and if the aggregate was fine. (Sand) is partially replaced aby using Rice husk ash with various variations starting from 0%, 5%, 10%, 15%. In addition, this utilization is a good alternative, because there will be a process of utilizing rice husk ash which was previously wasted while these items can be used or processed into additives to the concrete mixture.

Simulation of ultrasonic propagation in porous cellular concrete materials

While nondestructive ultrasound-based methods are suitable for evaluating the physical and mechanical properties of lightweight cellular concrete (LCC) materials, the quantitative relation between porosity characteristics and acoustic parameters is not well understood. In this study, the micromechanics-based finite-element models are rebuilt using the real porous microstructure of LCC. Various roles of porosity characteristics are analyzed, including equivalent pore radius, pore sphericity value and fractal dimension of pore distribution with different mixture ratios. Effects of porosity characteristics are quantitatively demonstrated on the ultrasonic pulse velocity. It is shown that the ultrasonic pulse velocity is positively correlated with equivalent pore radius and fractal dimension of pore distribution, and negatively correlated with pore sphericity value and porosity. As the orientation of pores increases, the ultrasonic pulse velocity initially drops, followed by the increase. The quantitative understanding of porosity characteristics on ultrasonic responses helps improve the accuracy of ultrasonic detection on LCC properties. Comparisons between simulation results and experimental data of ultrasonic pulse velocities demonstrate good agreement. This study represents an effective quantitative method to explore the ultrasound propagation in LCC.

Influence of Lightweight Aggregate Concrete Materials on Building Energy Performance

Due to their porous nature, lightweight aggregates have been shown to exhibit thermal properties that are advantageous when used in building materials such as lightweight concrete, grout, mortar, and concrete masonry units. Limited data exist on the thermal properties of materials that incorporate lightweight aggregate where the pore system has not been altered, and very few studies have been performed to quantify the building energy performance of structures constructed using lightweight building materials in commonly utilized structural and building envelope components. In this study, several lightweight concrete and masonry building materials were tested to determine the thermal properties of the bulk materials, providing more accurate inputs to building energy simulation than have previously been used. These properties were used in EnergyPlus building energy simulation models for several types of commercial structures for which materials containing lightweight aggregates are an alternative commonly considered for economic and aesthetic reasons. In a simple model, use of sand lightweight concrete resulted in prediction of 15–17% heating energy savings and 10% cooling energy savings, while use of all lightweight concrete resulted in prediction of approximately 35–40% heating energy savings and 30% cooling energy savings. In more complex EnergyPlus reference models, results indicated superior thermal performance of lightweight aggregate building materials in 48 of 50 building energy simulations. Predicted energy savings for the five models ranged from 0.2% to 6.4%.

Testing of nutmeg shell as a lightweight concrete material in terms of volume weight and compressive strength value

Lightweight concrete can be defined as a type of concrete which includes an expanding agent in that it increases the volume of the mixture while giving additional qualities such as nailibility and lessened the dead weight. The nutmeg shell has the characteristics of light and hard skin testure so that it has the potential to be used as a material for lightweight concrete. The purpose of this study is to determine the aggregate characteristic value and the compressive strength value of concrete using the DOE (department of environment) method and referring to standards SNI. Variation of use nugmet shell toward the weight volume of concrete is 10%, 20%, 30%, 40% and 50%. This research is a sample-based laboratory research and analysis of aggregate characteristics and concrete compression test. The research result shows that the use of nutmeg skin as a coarse aggregate material in the concrete mixture affects the volume weight of the concrete. The weight of the concrete gets lighter along with the higher the percentage used. The average volume weight obtained was 1810.06 kg / m3. Based on the weight of the concrete sample, it is classified as light structure, includes concrete with low density and includes lightweight aggregate concrete. The compressive strength values for the characteristics of concrete at a composition of 10%, 20% and 30% were obtained at 28.42 kg/cm2, 31.65 kg/cm2 and 32.68 kg/cm2 which increased while the use of nutmeg shells at 40% and 50% compositions was obtained. values of 29.09 kg/cm2 and 27.38 kg/cm2 decreased at the age of 28 days. The increase in the value of the compressive strength of concrete (fck') occurred starting at the composition of 20% and 30% at 10.20% and 13.03% and begin to decrease at the composition of 50% by 3.65%. Lightweight concrete from nutmeg shells has an weight of 1810,06 kg/m3 and a maximum compressive strength value of 3,2 MPa so that the concrete is in the category lightweight structure.

Lightweight concrete in cement-treated subbase construction

Following the development of transportation technology, steady road infrastructure is needed. The choice of construction type is a crucial point for the expected quality. Road construction consists of flexible and rigid pavement construction. Rigid pavement has higher durability and is produced from concrete, a strong, flexible, and fire-resistant material. Lightweight concrete, containing high amounts of pores, can be produced by using lightweight aggregate or a mixture of lightweight-coarse aggregate fulfilling the requirements for compressive and flexural strength. This study evaluated the compressive and flexural strength of lightweight concrete without coarse aggregate as a rigid pavement material. This study used specimens from type I Portland cement for compressive and flexural strength test, in 0.5 water-cement ratios and the specific gravity of 1.0. The result revealed a compressive strength value of 38.91 kg/cm2 and a flexural strength value of 1.32 MPa. Based on the results obtained, it was concluded that lightweight concrete material fulfilled the general specification criteria for the compressive strength requirements of the cement-treated subbase (CTSB).

Long-Term Sustainability Approach in Road Traffic Noise Wall Design

Despite the long-term experience in the application of noise walls, the uncertainty in wall panel service life efficiency is almost equal between panels built from established and new materials, which are—because of the desire to increase the sustainability of noise walls—developing at an ever-faster pace. The presented meta-analysis of data collected during a systematic review of concrete, metal, and wood panels’ acoustic and non-acoustic characteristics, long term performance, and cradle-to-gate sustainability aims to reduce this uncertainty and support the process of noise wall design and management by shifting the emphasis in decision making from construction costs to the long-term sustainability of the road traffic noise mitigation project. The multi-criterial analysis showed that when choosing a panel, preference should be given to those using lightweight concrete materials. A further comprehensive cradle-to-grave assessment of lightweight concrete panels with expanded clay and recycled tire rubber aggregates, which was performed to fill a knowledge gap observed in the literature and identify opportunities for the improvement of lightweight concrete sustainability, showed that the main environmental impacts of these panels are due to their production processes and that the way to reduce such impacts is to use panels made with aggregates from secondary raw materials.