Properties Of Lightweight Concrete Research Articles

Effect of Expanded Perlite Aggregate and Silica Fume on Some Properties of Lightweight Concrete

The lightweight concrete is manufactured from aggregates (expanded perlite) with a density of 145 kg/m3 and an absorption of 1.65%. This study has two aspects: a theoretical aspect that includes previous research on this concrete and a practical aspect that provides for conducting two groups of mixtures and preparing them according to ACI 211.2-98 design method. The first group includes cement, perlite, and water, and the second group consists of the addition of superplasticizer and silica fume, Each group included five series with three variables for each series. In the first series, the cement content was changed with a content of (275,300,350) kg/m3 with a volumetric mixing ratio (1:4), while in the second series, the aggregate content was changed only with a cement content of (275) kg/m3 with mixing ratios (1:4.1:5, 1:6) with a ratio of water to cement (0.4), and in the third series (superplasticizer) type (F) is added in different proportions, in the fourth series silica fume was added in three proportions (5%, 10%, 15% ) By replacing the weight of cement and the fifth series, the optimum contents were determined, which have acceptable workability, low density, and compressive strength commensurate with the density. Tests (flowability, dry density, and compressive strength) were carried out. It was observed that the workability, dry density, and compressive strength decreased with increasing perlite content but improved with the addition of superplasticizer and silica fume. The percentage of increase in density was (9% and 32%) at the optimum value of silica fume in 28.7 days, respectively. As for the compressive strength, the percentage of increase was (30% and 36%) in 7 and 28 days, respectively.

Effect of Expanded Polystyrene Beads on Mechanical, Thermal, and Acoustic Properties of Lightweight Concrete

Effect of Expanded Polystyrene Beads on Mechanical, Thermal, and Acoustic Properties of Lightweight Concrete

Impact of fine lightweight aggregates and coal waste on structural lightweight concrete: Experimental study and gene expression programming

Light Expanded Clay Aggregate (LECA) is one of the materials used to make lightweight concrete. In this study, two types of lightweight aggregates including LECA in both coarse and fine aggregate forms and pumice in fine aggregate form have been used to produce lightweight aggregate concrete. Coal waste is also used as partial replacement for cement. The results show that the usage of pumice as partial replacement for sand and LECA as coarse aggregate is applicable and can used for producing structural lightweight aggregate concrete. Furthermore, by using and increasing in the amount of LECA as fine aggregate, the slump of lightweight concrete in comparison to using sand, is also increased. The mixtures with LECA in both fine and coarse aggregate forms have the best results. Also, the results show that adding the coal waste improves the properties of lightweight concrete, and the optimal ratio is about 15% as partial replacement for cement by weight. In addition, gene expression programming is employed to establish empirical connections derived from experimental outcomes. In this regard, a relationship is proposed to determine the compressive strength of lightweight aggregate concrete based on the experimental data. The outcomes of gene expression programming demonstrate that the suggested formula exhibits good accuracy and efficiency in forecasting the specified parameter.

EXPERIMENTAL STUDY ON LIGHTWEIGHT CONCRETE USING LECA MATERIALS

This study investigates the feasibility of incorporating Lightweight Expanded Clay Aggregate (LECA) materials into concrete to produce lightweight concrete with improved mechanical properties. The experimental approach involves varying proportions of LECA aggregate in concrete mixes and assessing their compressive strength, density, workability, and durability. Additionally, the study examines the effect of LECA aggregate on the thermal and acoustic properties of lightweight concrete. Results from the experiments demonstrate the potential of LECA as a viable lightweight aggregate in concrete production, offering insights into optimizing mix designs for enhanced performance and sustainability in construction applications.

Mechanical and Durability Evaluation of Latex Modified Lightweight Concrete

Modified polymer concretes are popular materials in the construction industry due to their relatively high performance, versatility and stability compared to ordinary cement concrete. In this research, by adding three different latexes, including styrene butadiene rubber, ethylene vinyl acetate and acrylic latex, the mechanical and durability properties of Light weight concrete with Leca aggregates were measured. In this regard, 15 different mixtures are carried out in two laboratory programs. in the first stage, the effect of each latex with 5, 7.5 and 10% percentages with cement are investigated, and in the next stage, the simultaneous effect of latex with Microsilica. It was measured on the properties of lightweight concrete. The results showed that the addition of latex has a significant effect on increasing the durability factors of lightweight concrete several times. With the combination of 7.5% latex and 7% Microsilica, the best compressive strength has been recorded. By using latex, the flexural strength of concrete increased around 30%. Also, the passing charge of the lightweight concrete sample without latex is 4124 coulombs, while the sample containing 10% ethylene vinyl acetate passes 451 coulombs of charge.

A REVIEW OF THE EFFECT OF ADDITIVES ON THE MECHANICAL PROPERTIES OF LIGHTWEIGHT CONCRETE

Many organizations around the world have recognized lightweight, long-lasting, cost and environmentally-friendly construction materials as a future necessity. The lightweight concrete is manufactured mainly either by replacing the original aggregate with lightweight aggregate or addition foam production materials to concrete mixtures. These additions lead to a decrease in the lightweight concrete density and change mechanical properties such as compressive strength. Therefore, there is much experimental research has been conducted to add different material types that can improve lightweight concrete compressive strength while maintaining low density. In this review, the effect of various additions such as steel fiber, product waste materials, and nano-materials on the lightweight concrete compressive strength and density have been explained. The various effects of these additive materials on lightweight concrete properties, some additives lead to improving the properties of lightweight concrete, while other materials lead to a decrease in those properties, and this depends on the type and amount of material additive, the method lightweight concrete manufacturing, and their mixture composition.

Possibility to manufacture lightweight concrete from aluminum powder, mineral additives, and binders without cement

Lightweight concrete is an unburnt artificial stone with a dry density in the range of 500 kg/m3 to 1800 kg/m3. In addition, concrete with a dry density of less than 500 kg/m3 is considered to be particularly light concrete. This article presents some experimental results on the composition and properties of lightweight concrete using materials available in Vietnam. Materials used include fly ash, blast furnace slag, TOTO ceramic powder, aluminum powder, and activated alkaline solution. The experimental results show that there is a potential to be a good quality lightweight concrete, with a dry density of less than 1800 kg/m3 and a compressive strength at the age of 28 days ranging from 15–25 MPa. With an activated solution/total Alumino-sicate material content of 0.40, a ceramic powder of 20%, and an aluminum powder content of 0.35-0.40 kg per cubic meter, lightweight concrete of density 1600kg/m3 and compressive strength at the age of 28 days was the highest.

Research on some properties of lightweight concrete using recycled expanded polystyrene aggregates

This paper presents an experimental study to determine the effects of recycled expanded polystyrene aggregates (REPS) on workability, compressive strength, flexural tensile strength, and concrete density. REPS was used with four levels of content: 30%, 40%, 50%, and 60% by volume of concrete. The result shows that when increasing the REPS content, the workability of the concrete mix decreases, especially when the REPS content used is up to 50-60%. The density of recycled expanded polystyrene concrete (REPSC) can be adjusted to 800-1000 kg/m3 when the REPS content is up to 50%-60%. The compressive and flexural tensile strengths of the REPSC tended to decrease sharply with increasing REPS content. In addition, the influence of the REPS on the flexural tensile strength was lower than that on the compressive strength. The strength of the REPSC can be adjusted by changing the strength of the binder phase through factors such as the W/C ratio and binder content.

Investigation of the mechanical properties of lightweight concrete using expanded polystyrene reinforced with glass fibers

The use of lightweight concrete has gained popularity in the industrial construction sector owing to its ability to reduce dead weight and enable smaller cross-sections of beams. Adding expanded polystyrene to replace a portion of fine aggregate is a widely accepted solution to decrease the weight of concrete. However, lightweight expanded polystyrene concrete (EPSC) has poor mechanical properties and brittleness, limiting its application to non-bearing structures and thermal isolation. Glass fiber reinforcement is a promising solution to improve the mechanical properties of lightweight expanded polystyrene concrete. This study investigates the effect of glass fiber content on the mechanical properties of lightweight expanded polystyrene concrete. To investigate the impact of glass fiber on the mechanical properties of concrete, various volume percentages of glass fiber were incorporated into the mixture. The compressive and tensile strengths of the concrete were measured and compared for each percentage of glass fiber added. The results showed that the addition of glass fiber significantly reduced workability without causing a significant impact on volume density and compressive strength The study concludes that glass fiber reinforcement is a promising solution to improve the flexural strength of lightweight expanded polystyrene concrete and make it suitable for load-bearing applications in construction.

Experimental study of lightweight concrete prepared from super absorbent polymers (SAPs) and glass fibers (GF)

ABSTRACT This study investigates the effect of super absorbent polymers (SAPs) and glass fiber (GF) additions on the properties of lightweight concrete. The SAPs act as a pore-forming agent, with the addition of various GF contents (0.1–1.0% by weight of dry ingredients). The results indicate that the use of SAPs at 7% by weight of OPC produces a product with similar properties to conventional lightweight concretes which meet the ASTM C332–17 standard. The addition of GF to the mixture tends to reduce the dry density and compressive strength, but increases the porosity and flexural strength. The results indicate that the use of SAPs at 7% by weight of OPC produces a product with similar properties to conventional lightweight concretes which meet the ASTM C332–17 standard. The 28-day compressive strengths decreased from 7.04 ± 0.07 for control sample to 4.59 ± 0.11 MPa, while the flexural strengths increased from 3.89 ± 0.04 for control sample to 6.72 ± 0.06 MPa. High-porosity lightweight concrete prepared from SAPs and GF shows reduced thermal conductivity and an increased sorption rate. The initial rate of water absorption gradually increases from 2.48 × 10−1 mm/sec0.5 in the sample without GF up to 5.45 × 10−1 mm/sec0.5 in the sample containing 1.0 wt.% GF. Comparison with the literature indicates that the use of SAPs as pore-forming agents in conjunction with GF has the potential to produce fiber-reinforced lightweight concrete with improved properties.

Application of Stochastic Finite Element Modeling to Reinforced Lightweight Concrete Beams Containing Expanded Polystyrene Beads

Limited investigations have evaluated the effect of expanded polystyrene (EPS) beads on the structural lightweight concrete properties. EPS offers many features compared to natural or artificial lightweight aggregates including the elimination of aggregate saturation prior to concrete batching, ability to be fabricated on site, consistency in size and quality, and reduced cost. The main objective of this paper is to assess the suitability of finite element (FE) modeling based on deterministic and stochastic approaches to predict the shear strength behavior of reinforced concrete (RC) beams containing EPS additions. Test results showed that the experimental load-deflection properties recorded at failure can be well reproduced using both FE approaches. Nevertheless, the damaged-zone distribution and crack patterns that occur during the loading stages of RC beams cannot be approximated using the deterministic FE approach. In contrast, the stochastic method was quite suitable as it accounted for the concrete heterogeneity and altered spatial mechanical properties (such as compressive strength, splitting tensile strength, and Young’s modulus) due to EPS additions. Such data can be of interest to civil engineers seeking to predict the failure patterns and performance of structural lightweight members while reducing the time and resources needed to account for the concrete’s strength variability during experimental testing.

A state-of-the-art review - mechanical properties of light weight concrete by utilizing sintered fly ash aggregate

Utilization of concrete increases rapidly which led to depletion of natural resources. In order to resolve problem on scarcity of coarse aggregate, various artificial aggregate material can be partially replaced in coarse aggregate like sintered fly ash aggregate, palm kernel shell or coconut shell can reduce disposal problems. Harmful effect of concrete can be reduced by iterate structural efficiency and its performance characteristics of concrete. Present findings focuses on feasibility of making structural light weight concrete using sintered fly ash aggregate and researches on use of sintered fly ash aggregate and other material as partial replacement of coarse aggregate for producing light weight concrete. According to a literature review, these aggregates are 16–46% lighter and more capable of absorbing water than aggregates of similar weight. The concrete produced using sintered fly ash demonstrated strong mechanical and structural qualities. Sintered fly ash aggregate concrete has compressive strength between 22 and 43 MPa and densities between 1600 and 2000 kg/m3. Concrete made using fly ash aggregate appears to function well in structural applications. Concrete using sintered fly ash aggregate has been considered as a possible structural concrete material.

Effect of Pre-Soaking Treatment Method of Plant-Based Aggregate on the Properties of Lightweight Concrete—Preliminary Study

This research investigates the effect of pre-soaking treatment on plant-based aggregate using a wet grout binder to formulate a high-strength lightweight concrete (HSLWC). Surface modification utilising a novel grout soaking technique with various water-to-cement (w/c) ratios has indicated a new method of approach for the recent development of lightweight plant-based aggregate (LWPA). In this experiment, the fresh and hardened properties of modified LWPA lightweight concrete were assessed by verifying their workability, densities, compressive and split tensile strengths towards the modulus of elasticity. The results showed that pre-soaking plant-based lightweight aggregate (w/c: 0.6, 0.8, 1.0 and 1.2) slightly increased the density of the samples compared to untreated LWPA. The oven-dry density of treated and untreated LWPA is controlled in the range of HSLWC. The outcomes indicated that the workability of the surface-modified LWPA is significantly improved: up to 40% in 6 min for the (TDS)/0.6 sample compared to the original LWPA. The mechanical properties of the LWPA concrete with the surface modification method exhibit a substantial increment of compressive strength, split tensile strength and the modulus of elasticity; recorded at 22%, 26% and 34%, respectively. Significantly, the findings from this experiment reveal that the pre-soaking treatment method on LWPA is shown to be a highly recommended technique in improving interfacial bonding while maintaining its performance as one of the most promising solutions to improve the properties of lightweight concrete.

Recycling of Tire-Derived Fiber: The Contribution of Steel Cord on the Properties of Lightweight Concrete Based on Perlite Aggregate.

The increasing amount of waste from the vulcanization industry has become a serious environmental challenge. Even the partial reuse of the steel contained in tires as dispersed reinforcement in the production of new building materials may contribute to reducing the environmental impact of this industry while supporting the principle of sustainable development. In this study, the concrete samples were made of Portland cement, tap water, lightweight perlite aggregates, and steel cord fibers. Two different addition of steel cord fibers (1.3% and 2.6% wt. of concrete, respectively) were used. The samples of lightweight concrete based on perlite aggregate with steel cord fiber addition showed a significant increase in compressive (18-48%), tensile (25-52%), and flexural strength (26-41%). Moreover, higher thermal conductivity and thermal diffusivity were reported after incorporating steel cord fibers into the concrete matrix; however, the specific heat values decreased after these modifications. The highest values of thermal conductivity and thermal diffusivity were obtained for samples modified with a 2.6% addition of steel cord fibers and were equal to 0.912 ± 0.002 W/mK and 0.562 ± 0.002 µm2/s, respectively. Maximum specific heat, on the other hand, was reported for plain concrete (R)-1.678 ± 0.001 MJ/m3 K.

Effects of Kortta fibres and microsilica on the mechanical properties of lightweight concrete in oil product environments

Crude oil and its products are strategic and vital goods for most countries in the world. It is necessary to store these products in the production and transfer chain and send them to refineries, ports, and airports for military and national purposes. Lightweight concrete is propounded as a useful replacement for normal concrete due to its low specific weight and acceptable resistance property; however, compared to normal concrete, it is considered to be more permeable, less durable, and less resistant. Therefore, in this study, the reliability of this synthetic material in oil conditions has been investigated. In this regard, two groups of samples were investigated under normal and oil environmental conditions, polymer Kortta fibres with percentages of 0; 0,5; 1,0; 1,5; and 2,0 % and microsilica with percentages of 0 and 15 % by cement weight were incorporated alone and combined. Subsequently, tests were performed on the specimens after 90 days. The results showed that the combination of microsilica and Kortta fibres causes a significant increase in lightweight concrete strength and impermeability.

Optimization of the Mechanical and Physical Properties of Lightweight Concrete Reinforced with Date Palm and Sisal Fibers

This work investigates the influence of date palm and sisal fibers on the mechanical and physical behavior of lightweight concrete based on expanded clay aggregates. The choice of these fibers types is aimed at the recovery of agricultural waste in Tunisia. Their exploitation serves to improve the mechanical and physical properties of a new material dedicated to filling and insulation in buildings. In this context, series of tests were carried out using untreated short fibers in lightweight concrete. The evaluation of the mechanical and physical behavior of the material was obtained by determining the compressive strength, bending strength and thermal conductivity. The results obtained showed the influence of the fibers volume fraction. For mechanical behavior, the optimum of fibers volume fraction was estimated at 1% for lightweight concrete with date palm and sisal fibers. The thermal conductivity is inversely proportional to the fibers volume fraction, which justifies the use of this composite as a filling and insulation material.

Impact of fly ash and bagasse ash on durability performance of lightweight concrete with the experimental study

Lightweight concrete [LWC] is rapidly reaching its full potential for a broad range of applications in the construction of concrete structures. It is tailor-made material for specific applications having beneficial properties. Therefore, the paper is devoted to the experimental analysis and study of fly ash and bagasse ash on the durability properties of lightweight concrete. Durability can be defined as the ability of the material to withstand the effects of its environment which are influencing the deterioration of concrete. The saturated water absorption and sorptivity was studied through experimental investigations, by varying the percentage of fly ash and bagasse ash content. Both fly ash and bagasse ash shows that the increase in the percentage of replacement leads to the more absorption of lightweight concrete. The results are investigated and presented on the studies conducted as follows, showing that the increases in the percentage of replacement, strength also increased.

Central composite design application in the optimization of the effect of pumice stone on lightweight concrete properties using RSM

Among other lightweight aggregates, one choice is pumice stone (PS), which can replace coarse aggregates in concrete. In this study, the natural coarse aggregates are replaced by various percentages of PS in concrete to examine its physical and mechanical properties. Experiments are designed to prepare mixtures (by varying ratios of PS) using response surface methodology (RSM). Slump and compaction factor tests are used to investigate the fresh properties, such as the workability of concrete. In contrast, the hardened concrete properties are determined using compressive strength (CS), flexural strength (FS), and split tensile strength (STS). The experimental, optimization and validation of the model results show that up to 30% of the PS can be replaced in the lightweight aggregate concrete for 7 – 56 curing days in which the CS is greater than 15 MPa, STS is 7–12% of the CS, and FS is 9 – 11% of the CS. Therefore, the optimum CS for the current study ranges from 17 to 20 MPa, in which the STS is 9.39 – 10.54% of the CS, and FS ranges from 17.49% to 21.12% of the CS. The quadratic model was proposed, and the ANOVA and model fitness was produced through RSM, with the coefficient of determination (R2) above 0.99 (99%) for all three responses representing the high importance of the suggested model. Besides, the difference among the R2 and adjusted R2 was negligible, and the P-Value for CS, STS, and FS was below 0.05 (<0.0001), indicating the model's high relevance. RSM was used to improve the model, which was then verified in further lab trials.

Transport Properties of Lightweight Concrete Incorporated with Expanded Clay Aggregate in Marine Environment

Employing porous material such as expanded clay lightweight aggregate (EC LWA) as an internal curing agent in the production of mass concrete proof to mitigate early age cracks in resulting concrete. However, introducing EC LWA could increase the porosity of concrete, leading to concrete degradation due to water penetration. Thus, this research aims to investigate the suitable natural aggregate replacement rate with EC LWA in the production of concrete with acceptable mechanical and transport properties. Three replacement rates of 0, 50, and 100% were applied. The water-per-cement ratio of 0.6 was used to produce concrete. The workability of fresh concrete and the compressive strength were tested. The transport properties of concrete were assessed by monitoring the capillary water uptake of concrete. To mimic the marine environment, the concrete sample was immersed in sodium chloride and sodium sulphate for seven days. The result shows that the workability, bulk density, and compressive strength of concrete with 50% EC LWA have a similar value to the reference sample. Moreover, samples with 50% EC LWA also have a slower capillary rate in a sodium chloride environment than in fresh water.

Assessment of Different Properties of Lightweight Concrete using Expanded Polystyrene Beads Extracted from Thermocol Wastage

Nepal is facing the problem of thermocol wastage, especially in the damping site nearby the urban areas. The thermocol wastage were crushed by a hammer and the extracted expanded polystyrene (EPS) beads was used as aggregates to produce the lightweight concrete. The content of EPS beads was 0, 20, 30, 40, 50, and 60 % by the total volume. Mechanical properties like density, different strengths, and Young’s modulus were experimentally evaluated on ranging percentages of EPS. The 28-day compressive, flexural, splitting tensile strengths and Young’s modulus of the control mixture were 59.9 MPa, 5.21 MPa, 4.43 MPa, and 20898 MPa respectively. The decrease on compressive strength was by 62 %, 72 %, 81 %, 88 %, and 93 % respectively for 20 %, 30 %, 40 %, 50 %, and 60 % EPS content respectively. It was 26 %, 41 %, 51 %, 57 %, and 69 % for flexural strength, 46 %, 60 %, 70 %, 80 %, and 88 % for the splitting tensile strength and 45 %, 56 %, 61 %, 70 %, and 77 % for Young’s modulus respectively. Drying shrinkage, freezing and thawing, and water absorption tests were conducted to evaluate the durability of EPS concrete. All properties were compared with the auto-cleaved lightweight concrete (ALC). It revealed that the EPS beads extracted from the thermocol wastage can be re-used to produce the structural and non-structural concrete depending on its percentages. It can easily solve the never-decomposing problems of thermocol wastage. Moreover, ALC can be replaced by EPS concrete for the in-fill and partition walls of the buildings.