The use of cement leftovers from the hollow of spun piles as an additive in self-compacting concrete

Spun piles have been used widely by developing countries, including Malaysia, to construct the foundation of most construction projects. A spun pile is a reinforced precast and prestressed concrete that is compacted in a mould through spinning compaction. The spinning compaction produces cement leftovers in the hollow part of spun piles that can be added to concrete mixtures as an additive. The cement leftovers of spun piles were used as an additive in cement in range of 0%, 10%, 20% and 30% (equal percentages). The resulting compressive strength after curing periods of 7 days and 28 days were presented to investigate the properties of self-compacting concrete containing cement leftovers from the spun piles. Other properties investigated include the physical properties of fresh concrete and water absorption. The results indicated that higher compressive strength and lower water absorption were achieved by the concrete samples containing cement leftovers compared to controlled concrete

Nonlinear finite element analysis of reinforced concrete beams strengthened with textile fine grained mortar

Nowadays, there was an increasing need of repairing and upgrading the reinforced concrete (RC) structure due to the deterioration of the structure. The fibre reinforced polymer (FRP) was commonly used for structural retrofitting purposes. However, owing to the debonding of the FRP from the concrete substrate and high cost of epoxy, it was gradually replaced with textile fine grained mortar (TFGM) nowadays. The TFGM system has been widely used in the construction field nowadays to repair the structure. Our study focus on the strain performances of the concrete surface, steel reinforcement and the textile itself. There were many proven experimental results showing that the TFGM was more effective than the other strengthening method such as FRP plate method. The experimental work done by previous researcher on investigation of strain performances of the concrete surface, steel reinforcement and the textile itself which consists of eleven (11) RC beams with dimension 150 x 200 x 2500 mm. The RC beams were strengthened with FGM and TFGM with 4 layers. The investigation continued with the finite element (FE) strain performance analysis with using Advanced Tool for Engineering Nonlinear Analysis (ATENA) software. The strain of the concrete surface, steel reinforcement and the textile were measured at a mid-point of RC beam. Then, the results of the finite element analysis software ATENA compared against the experimental results. The strain performances of the concrete and steel reinforcement improved noticeably when the number of layers of textile reinforcement used increased

Flexural behaviour of plain concrete prism strengthened by textile fine grained mortar

This paper presents a flexural strength study of concrete incorporated with textile fine grained mortar (TFGM) as a strengthening laminate. TFGM is a combination of fine grained mortar (FGM) with alkali resistant glass fabric (AR glass). Fine grained sand with 600 m maximum size was used in FGM and fly ash (FA) or rice husk ash (RHA) has been used as a partial substitute for ordinary Portland cement (OPC). The potential of TFGM as strengthening laminate was tested under monolithic load with three point flexure loading. The TFGM were laid in layers of two, four, six, and eight. Results shown a promising flexure enhancement of up to three times of unstrengthened concrete when eight layers of both RHA and FA were laid. Load bearing capacity and ductility of the samples increased about 200% and 61%, respectively, compared to control samples as well. The outcome shows a highly potential use of agro-waste as cement replacement to produce load bearing structural component

Thermal Conductivity Of Lightweight Concrete Block With Various Cooling Agent

Energy was the important sources to human life. Due to increases energy demand in daily life, the energy consumption was increase day by day because of the heat load from solar radiation and heat produced by people. Toward sustainable development, this research was carried out to develop a lightweight concrete (LWC) block with various cooling agent such as glycerine, propylene glycol, coconut shell and gypsum powder. Six lightweight concrete (LWC) block with the size 250mm (L) × 250mm (W) × 100mm (T) were tested for thermal conductivity value.  From the experimental result, it shows that lightweight concrete (LCW) block with various cooling agent obtained thermal conductivity value of 0.17W/mK - 0.36W/mK lower than thermal conductivity value for normal lightweight concrete (0.8W/mK) depending on concrete density.  The lightweight concrete (LCW) block with cooling agent having low thermal conductivity value will reduce energy consumption in building

Binary Effect of Fly Ash and Waste Glass on Compressive Strength and Heat of Hydration for Concrete

The most crucial building material in the modern construction industry is concrete. Concrete made of components like cement and aggregates. Cement was a significant contributor to the carbon dioxide emissions that altered the world's climate and had other detrimental effects on the environment. Concrete is used so frequently in the construction industry that it is crucial to conduct research on this topic since it will affect how long a structure lasts. In an effort to decrease the detrimental effects on the environment and enhance the qualities of concrete, alternative materials, such as fly ash (FA) and waste glass (WG), have been utilised to replace some of the fine aggregate and ordinary Portland cement (OPC), respectively. Compressive strength testing and hydration heat assessment were used in this study. Fly ash and waste glass were substituted for normal concrete in amounts ranging from 5 to 25% by weight of the cement and fine aggregate, respectively. For the compressive strength test, 36 concrete cubes with dimensions of 100 mm x 100 mm x 100 mm were created. They were evaluated after 7 and 28 days. Six (6) new concrete samples of 150 mm in diameter and 300 mm in height were prepared in order to access the heat of hydration of concrete. According to the study, the concrete with 5% replacement of FA and WG had the highest compressive strength at both 7 and 28 days, according to the results, out of all the tested mixes. In addition, 13 hours after casting, the control concrete mix design recorded the 37°C peak temperature, which was the highest of all the concrete mixes

Strength, water absorption and thermal comfort of mortar bricks containing crushed ceramic waste

This present study investigated the crushed ceramic waste utilisation as sand replacement in solid mortar bricks. The percentage of crushed ceramic waste used were 0% (CW0), 10% (CW10), 20% (CW20) and 30% (CW30) from the total weight of sand. The dimension prescribed of mortar bricks are 215 mm x 102.5 mm x 65 mm as followed accordance to MS 2281:2010 and BS EN 771-1:2011+A1:2015. Four (4) tests were conducted on mortar bricks namely crushing strength, water absorption, compressive strength of masonry units and thermal comfort. The incorporation of ceramic waste in all designated mortar bricks showed the increment of crushing strength between 23% and 46% at 28 days of curing and decrement water absorption between 34% and 44% was recorded corresponding to control mortar bricks. The prism test of masonry units consists of mortar bricks containing ceramic waste indicated the high increment of compressive strength at about 200% as compared to mortar brick without ceramic waste. The thermal comfort test of ceramic mortar bricks were also showed the good insulation with low interior temperature. Therefore, the ceramic waste can be utilised as a material replacement to fine aggregate in mortar brick productions due to significant outcomes performed

The effect of curing conditions on the strength of masonry blocks incorporating palm oil fuel ash

Palm Oil Fuel Ash (POFA) is a by-product of the palm oil industry that is often disposed at landfills. In oil palm-producing countries such as Malaysia, Indonesia and Thailand, the high amount of POFA waste disposal is undoubtedly an environmental problem that needs to be overcome to contribute towards zero-carbon emissions by 2050. This paper presents the incorporation of POFA as a partial cement replacement in the production of concrete masonry blocks – a common building material in developing countries. In this study, the cement con�tent by weight of a conventional concrete masonry block was replaced incremen�tally at 10% interval until 30% with ground POFA. The specimens were either cured in water or left dry and tested after 28 days of curing for density, compressive strength and water absorption rate based on standard testing requirements. A general observation has been taken note on the superior results of water-cured masonry blocks with up to 20% POFA content. The results of this study is antic�ipated to add value to the present knowledge bank on incorporating waste material into sustainable building material research and development. In general, POFA is a highly potential replacement for cement, but further studies need to be done to ensure consistency in performance and for industrial application

Physico-mechanical properties of polymer concrete containing micro-filler of palm oil fuel ash

Objective of this study is to present a research conducted on ground (fine) and unground (coarse) POFA in polymer concrete (PC) followed by determination on the physico-mechanical properties of PC. Physical properties of micro-fillers and mechanical properties of produced PCs were characterized. Calcium carbonate and silica sand were also used as micro-fillers for comparison purpose. The samples were subjected to compression and flexural. Morphology images of the particles were captured under morphology test to support the findings. Results showed that fine POFA micro-filler has a highly promising potential in becoming PC filler compared to coarse micro-filler. Additionally, its produced PC had comparable strength to PC with calcium carbonate. From the strength development and sustainability stand point, fine POFA has demonstrated its capability to produce quality and sustainable P

Performance of independent horizontal and inclined bars as shear reinforcement for reinforced concrete beams

This paper presents an experimental results of concrete beams reinforced with new shear reinforcement design of using independent horizontal and inclined bars. A total of six beams, measuring 200 mm width x 250 mm height x 2300 mm length were tested up to failure under four-point loading. The effectiveness of using independent horizontal and inclined bars to the shear carrying capacity of the beam was investigated. The independent horizontal and inclined bars with reinforcement ratios between 1.0% and 2.9% were provided in reinforced concrete beams. All the beams were cast with normal grade of concrete compressive strength between 30 to 35 MPa. The performance of the tested beams in terms of ultimate load, mid-span deflection and crack patterns were recorded and compared. The test results showed that beams reinforced with independent horizontal and inclined bars of 1.9% and 2.9% experienced higher shear load capacities than beams with conventional shear reinforcement system. It can be concluded that the use of independent horizontal and inclined bars as shear reinforcement gives good shear resistant for the beams. Furthermore, these types of shear reinforcement system are more flexible, simple which significantly reduced the congestion of vertical links within shear span zone

Cooling panel wall system with difference types of cooling mediums

Global warming has caused worldwide average surface temperature to rise about 0.74oC during the past 100 years, which is partly aggravated by air-conditioning that releases chlorofluorocarbons (CFCs) and forming a vicious cycle. This paper proposes a cooling house system that can promote thermal comfort in buildings without air-conditioning. The cooling panel wall forms a part of an Integrated Building System (IBS), and is essentially made of tubes filled with either water or glycerin as the coolant. Target strength for the panel wall was designed based on the Malaysian Standard (MS) while the building ventilation system followed the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) standard. The results are reported based on indoor and outdoor temperature difference together with relative humidity to identify the best performing house model and also coolant. The outcome of this research is expected to add value to heritage house design concepts with a better promotion of air flow and circulation in the building, without over-usage of natural resources and higher building cost to achieve the same objective