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As almost half of the world's population now lives in the urban areas, the raise in temperature in these areas has necessitated the development of thermal insulating material. Conventional concrete absorbs solar radiation during the daytime while releasing it at night causing raise in temperature in urban areas. The thermal conductivity of 2200 kg/...
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There is an experimental study of samples of monolithic foam concrete “SOVBI” with a density of 205 kg /m ³ (grade D200) for combustibility. The evaluation criteria are the following values of combustion characteristics: temperature increment in the furnace, duration of the stable flame burning, sample mass loss. The experimental results show the f...
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... Therefore, foam concrete has lower density and strength compared to normalweight concrete. Short fibres have been found to be beneficial in improving the mechanical properties of foam concrete [4][5][6][7][8][9]. It was reported that the addition of 0.4% (by volume) polypropylene (PP) fibres enhanced the compressive strength of foam concrete by 35% [10]. ...
Fibre reinforcement is beneficial to control crack behaviour and the energy absorption ability of foam concrete. Several studies have investigated the flexural tensile behaviour of fibre-reinforced foam concrete to determine its ultimate peak strength gain. However, there remains a knowledge gap regarding the underlying mechanism of fibre influence on its tensile behaviour, as well as the impact of fibres on the pre and post-crack behaviour of foam concrete. This paper analysed and compared the flexural tensile behaviour and splitting tensile strength of PVA fibre-reinforced foam concrete. In addition, machine learning technology was used to develop regression models that described the importance of design parameters (foam concrete density, fibre length, diameter, and content), fibre distribution, and pore structure on foam concrete's tensile behaviour. The results show that the mechanism of fibre influence on pre-crack and post-crack flexural behaviour in foam concrete differs from that in normalweight concrete. In particular, contrary to the behaviour observed in normalweight concrete, PVA fibres noticeably enhanced the pre-crack flexural performance and splitting tensile strength of foam concrete. This paper found that this improvement is related to the effect of fibres on the pore structure in foam concrete, which in turn had a substantial impact on both pre-crack flexural behaviour and splitting tensile strength. Different from pre-crack behaviour (mainly influenced by pore structure), fibre content and size dominated post-crack behaviour of foam concrete. Optimising fibre size and content resulted in substantial improvements in splitting tensile strength (up to 75.3% for high-density foam concrete and 49.9% for low-density foam concrete) and flexural strength (up to 44.4% for high-density foam concrete and 117.9% for low-density foam concrete).
... The findings show that the highest TS was deter-mined to be 1.95 N/mm 2 (M3) for B1, 2.04 N/mm 2 (M5) for B2, 2.43 N/mm 2 (M9) for B3, 2.33 N/mm 2 (M10) for B4, 2.45 N/mm 2 (M15) for B5, 2.43 N/mm 2 (M16) for B6, and 2.81 N/mm 2 (M17) for B7. According to the results, the TS of FC increased with the addition of coarse aggregate [50,51]. It is also observed that the CS of FC is higher for mixes with a low foam volume. ...
The usage of foam concrete (FC) was extended from being used as a filler material to an alternative concrete due to the effect of conventional concrete on global warming. The diversified perspective on FC as an alternative to conventional concrete is due to its low density (400–1800 kg/m3) and good thermal conductivity, which also results in the reduction of costs in production, labor, and transportation. Generally, FC is produced by adding a pre-made foam to the cement slurry consisting of cement and aggregates. Here, the study was carried out by the addition of a coarse aggregate and foaming agent (i.e., 12%, 6%, 3%, 2%, 1%) at varying percentages in FC to improve the strength characteristics. FC was tested for its physical and mechanical properties. From the experimental results, an Artificial Neural Network (ANN) was developed to predict the strength of FC. The results from training and testing of the Polynomial Regression Analysis model (PRA) through ANN have shown great potential in predicting compression, split tensile, and flexural strength of FC. It was found that the strength of FC is increased with the reduction of foam volume and increase in coarse aggregate volume. However, a strength of 25.6 N/mm2 is achieved when 1% foam and 50% coarse aggregate is used.
... In addition to the low density, foamed concrete has demonstrated superior thermal insulation in contrast to other building materials over the years. Nowadays, with the increasing effects of global warming and urban heat island (UHI), the use of foamed concrete panels for thermal insulation is not only a revolutionary idea, but it has become a necessity [8]. ...
... The influence of UHI is observed in metropolitan urban areas, as seen in Fig. 1, with an average city temperature being warmer than the nearby rural areas [8,10]. In metropolitan cities today, high thermal energy in buildings and paving materials is the core factor in the production of UHI, which consequently raises the near-surface temperature due to its elevated thermal energy content. ...
The need for thermal insulating building material due to increase in Urban Heat Island effect and the carbon footprint associated with concrete due to its binder, cement, has caused increase in utilization of waste by-products as supplementary cementitious materials (SCMs). Vast number of waste materials are available which could be potential substitutes of cement and help in developing eco-friendly concrete, however, conducting various tests on these would be costly and time-consuming. Therefore, computational simulation is a cost-effective and time-saving alternative for thorough time-consuming and expensive experimental studies. The aim of current work was to conduct the finite element simulation to assess the performance of eco-friendly lightweight foamed concrete incorporating two such waste products, Eggshell Powder (ESP) and Palm Oil Fuel Ash (POFA) being subject to thermal stress, heat transfer and parametric analysis and comparing the simulated results with data obtained from experimental work. Based on the results, it can be concluded that the surface temperature of the eco-friendly lightweight concrete panels decreased as the thickness of the panels increased. The finite element model by using ABAQUS software was validated with experimental results, and it was determined that the simulated results were within an acceptable range of 10% which could reduce to 2% if all panels with a set thickness of 50 mm. Therefore, computational model could help predict thermal stresses and heat transfer and provide fast-track thermal performance analysis of eco-friendly lightweight concrete incorporating various waste materials.
... On the other hand, fibres not only improve the mechanical properties, but they can also contribute to lowering thermal conductivity of concrete too. Several authors have studied this effect, showing that that addition of Polypropylene fibres reduce it for densities lower than 1800 kg/m 3 , having the opposite effect with bigger densities [17,18]. ...
This research analyses the strain behaviour of fibre-reinforced concrete (FRC) in the event of a creep episode. The analysis of creep experienced by FRC specimens during the test reflects better performance than that predicted by the EHE-08 standard. The authors propose a formulation for the evaluation of creep strain undergone by FRC. During the research, the evolution of the modulus of elasticity of FRC after a creep episode is analysed. After the test campaign, it can be concluded that FRC loaded at an earlier age stiffens after a creep episode. After the creep test is completed, the delayed elastic strain undergone by FRC is analysed and it is observed that FRC loaded at an earlier age undergoes less deformation. The authors propose a formulation for the evaluation of the delayed elastic strain undergone by FRC after a creep episode.
... Foamed concrete is a type of lightweight concrete with different physical and mechanical properties compares to normal concrete. Foamed concrete can be designed ranging from 300 -1850 kg/m 3 as compared to normal concrete at 2400 kg/m 3 [1]. The foamed concrete which also known as cellular concrete without coarse aggregates was created by void in form of small bubble that utilize air molecules [2]. ...
Concept of sustainable construction has gradually become one of the concern issues in our construction industry in recent years. Concrete which acts as an important construction material has contributed to excessive consumption of natural resources. Simultaneously, tonnes of waste materials were produced from agricultural activity in form of palm oil fuel ash (POFA) while mussel shell from marine hatchery. Utilization of agricultural waste as cement replacement is an option to reduce the environmental impact from the construction industry. In this study, these waste materials were used as partial cement replacement to produce foamed concrete in wet density of 1800 kg/m ³ . The main purpose of this research is to study the workability and mechanical properties of foamed concrete which contain uniform 20% of POFA combined with 5% to 10% of mussel shell powder (MSP) and mussel shell ash (MSA) respectively. The cube specimens were cast in dimension 100 mm x 100 mm x100 mm to test the compressive strength at 7th and 28th. The cylinder specimens were cast in 100 mm diameter x 200 mm diameter for split tensile test to determine the tensile strength and compression test to determine modulus of elasticity at 28th day. The result showed workability of foamed concrete decreased as more cement was replaced by POFA combined with MSP and MSA. Foamed concrete mixture with 20% POFA and 5% MSP was selected as optimum percentage of cement replacement due to reduction less than 5% compromised performance in compressive strength at 16.52MPa while tensile strength at 1.83MPa.
... It shows that lower density mixtures absorb significantly higher percentages of water compared to those with higher densities. According to Jhatial et al. (2017), water absorption can be expressed as either an increase in mass per unit of dry mass or an increase per unit volume. In normal concrete, water absorption results are most likely to be relatively similar, no matter how they are expressed. ...
Worldwide, the construction industry has acknowledged the future demand for lightweight construction materials, with high workability, self-compacting, and environmentally friendly. Given this demand, recent innovative material namely foamed concrete (FC), has been found to reduce normal concrete’s weight potentially. However, while FC made with Ordinary Portland Cement has good compressive strength, other characteristics such as tension are relatively weak given the number of micro-cracks. Therefore, the study focused on the potential use of oil palm fibres in FC regarding their durability and mechanical properties. Notably, one of the major issues faced in the construction of reinforced FC is the corrosion of reinforcing steel which affects the behaviour and durability of concrete structures. Hence, in this study, oil palm fibres were added to improve strength and effectively reduce corrosion. Five types of fibre generated from oil palm waste were considered: oil palm trunk, oil palm frond, oil palm mesocarp and empty fruit bunch consisting of the stalk and spikelets. Specimens with a density of 1800 kg/m3 were prepared in which the weight fraction of the fibre content was kept constant at 0.45% for each mixture. Testing ages differed in testing and evaluating the parameters such as compressive strength, flexural strength, tensile strength, porosity, water absorption, drying shrinkage and ultrasonic pulse velocity. The results showed that the incorporation of oil palm fibre in FC helped reduce water absorption, porosity and shrinkage while enhancing the compressive, flexural and tensile strength of FC.
... Many researcher study foamed concrete in every aspect such as [3] regarding natural and synthetic foaming agent, and reference [1,2] observe the silica fume incorporation and their durability respectively. Reference [4] also describe FC generally, and [5] determine the polypropylene finer influence on their tensile strength, while [6] study the high volume but low density fly ash FC. Reference [5] conclude that the splitting tensile strength of foamed concrete increases as the amount of pore and voids decreases. ...
... Reference [4] also describe FC generally, and [5] determine the polypropylene finer influence on their tensile strength, while [6] study the high volume but low density fly ash FC. Reference [5] conclude that the splitting tensile strength of foamed concrete increases as the amount of pore and voids decreases. They also noted that the influence of PP fibers rises with decreasing foamed concrete density, as seen by the splitting tensile and thermal conductivity of all three foamed concrete densities [5]. Figure 1 depicted the bubble analysis image of high volume fly ash foamed concrete [6] Observation of the microstructure and mixture proportioning of FC with silica fume also done by [7] which explore the findings of an experimental investigation into the microstructure and proportioning of non-structural foamed concrete with silica fume (SF). ...
... Reference [5] conclude that the splitting tensile strength of foamed concrete increases as the amount of pore and voids decreases. They also noted that the influence of PP fibers rises with decreasing foamed concrete density, as seen by the splitting tensile and thermal conductivity of all three foamed concrete densities [5]. Figure 1 depicted the bubble analysis image of high volume fly ash foamed concrete [6] Observation of the microstructure and mixture proportioning of FC with silica fume also done by [7] which explore the findings of an experimental investigation into the microstructure and proportioning of non-structural foamed concrete with silica fume (SF). ...
A flexural behaviour of hat section lightweight fiberglass reinforced concrete beam was proposed. A rigid lightweight concrete beam is a structural component intended to sustain the bending or flexural load. The objective of this paper was to examined hat section lightweight concrete, to assess the STAAD.Pro software used to simulate hat section lightweight concrete beams, and to compare the deflection results. The needed data included a mix design for a change in fiberglass mixture and the dimensions of a hat section lightweight concrete beam. Laboratory tests, software modeling of a hat section lightweight concrete beam, and visual analysis of deflection, stress, and strain were used to evaluate the results. According to the study findings, the optimal fiberglass variation mixture included 1% and had a compressive strength of 2.85 MPa and a density of 1037.981 kg/m3. The deflection of a lightweight concrete beam with a hat section was 12.3 mm and 10.8 mm. Whereas the modeled deflection was 6,550 mm and 7,064 mm. As a consequence, the laboratory test results were consistent with the modeling results obtained using the STAAD.Pro software, with a difference of 5,750 mm and 3,736 mm.
... On the other hand, fibres not only improve the mechanical properties, but they can also contribute to lowering thermal conductivity of concrete too. Several authors have studied this effect, showing that that addition of Polypropylene fibres reduce it for densities lower than 1800 kg/m 3 , having the opposite effect with bigger densities [17,18]. ...
One of the biggest challenges in facilitating the installation of concrete is the development of fibre-reinforced concrete. Although nowadays fibre reinforced concrete is relatively common, it is still necessary to deepen in the study on its behaviour, especially regarding its fatigue behaviour. This paper proposes a new methodology to analyse the bending fatigue behaviour of notched test specimens. From these tests, it was possible to verify that, despite carrying out the tests with load control, the presence of fibres extends the fatigue life of the concrete after cracking. This effect is of great importance since during the extra lifetime with the cracked concrete, the damage to the concrete will be evident and the corresponding maintenance measures can be carried out. Regarding the analysis of the results, in addition to obtaining a traditional S-N curve, two new criteria have been applied, namely energy and notch growth. From these two new approaches, it was possible to determine critical energy values that can be used as predictive indicators of the collapse of the element. Moreover, from the notch growth analysis, it was possible to determine crack growth rate as a function of the stress conditions for the concrete and the specific geometry. From the comparison among the results obtained from the different tests, a limit cracking index of 0.05 mm can be defined.
... Concrete, despite being the preferred construction and building material, tends to absorb heat due to its relatively high thermal conductivity, which causes interior thermal discomfort for the occupants. This causes urban infrastructures to heat up compared to the adjacent rural areas (Jhatial et al., 2017), giving rise to the Urban Heat Island (UHI) effect. It has been reported that cities gain 2 ⁰C, while highly densely populated areas are up to 7 ⁰C higher than the surrounding rural areas, whereas they are warmer than the adjacent rural areas (Özyavuz et al., 2015). ...
Increased usage of concrete contributes to urban thermal discomfort due to the Urban Heat Island effect. At the same time, the corresponding increased consumption of cement also causes a significant rise in carbon dioxide (CO 2) gas emissions. This experimental work aims at evaluating the thermal and mechanical performance of 1800 kg/m 3 dry density green sustainable foamed concrete (GFC) incorporating agroindustrial waste such as Palm Oil Fuel Ash (POFA) and Eggshell Powder (ESP) as supplementary cementitious materials (SCMs). The POFA content varied from 15 to 35%, with increments of 5%, while being supplemented with 5% ESP. To evaluate the performance of the developed GFC, the flowability, mechanical strengths (compressive and splitting tensile strengths), and thermal performances (thermal conductivity and surface temperature) were investigated. Incorporation of 15-25% of POFA supplemented with 5% ESP as partial cement replacement materials resulted in enhanced mechanical strengths. Although usage of POFA can reduce the thermal conductivity, the POFA content must be limited to 15-25% to prevent excessive heat absorption by the exterior surface of the concrete. Overall, the optimum use of 15% POFA in a combination of 5% ESP is desirable to produce an eco-friendly sustainable foamed concrete.
... This is because the foam volume was lower for the density of 1,200 kg/m 3 compared with that of 600 kg/m 3 . It has been reported in previous research that an increase in the foam volume reduces the shrinkage due to the growth in pore sizes (Jhatial et al. 2017). A reduction of up to 36% in drying shrinkage was found as the foam volume rose to 50% of the total volume. ...
Researchers around the globe have recognised the potential need for lightweight, reliable, easy to use, affordable, and even more sustainable building materials. One of the vanguard proposals has been the procurement, development and use of alternative, non-conventional local building materials, which includes the possibility of utilising lightweight foamed concrete (LFC). LFC is excellent under compression but poor in tensile stress, as it produces multiple microcracks. LFC cannot withstand the tensile stress induced by applied forces without additional reinforcing elements. This research was conducted to examine the potential utilisation of oil palm mesocarp fibre-reinforced (OPMF) LFC in terms of its durability. Two densities, 600kg/m3 and 1200kg/m3, were cast and tested with five different percentages of OPMF, which were 0.00% (control), 0.15%, 0.30%, 0.45% and 0.60%. The parameters evaluated were water absorption, porosity, drying shrinkage, ultrasonic pulse velocity. The results revealed that the inclusion of OPMF in LFC helps to minimise water absorption and the porosity of LFC. Moreover, the inclusion of OPMF also improves the drying shrinkage and ultrasonic pulse velocity of LFC.
