Durability Performance of Palm Oil Fuel Ash Cement Based Aerated Concrete in Marine Environment

The ever popular issue on environmental preservation and sustainability all over the world has lead towards the innovation of new materials from either industrial or agricultural waste. Malaysia being one of the leading producers of palm oil has been conducting numerous researches to discover the various potentials of by-products generated by palm oil mills. The current findings revealed that palm oil fuel ash (POFA) produced in the mills can be used for producing a new alternative lightweight construction material known as POFA cement based aerated concrete having enhanced strength than specimen produced using 100% ordinary Portland cement. Since, the performance this material in marine environment is unknown, this paper presents and discusses the result on the strength performance of this lightweight concrete upon exposure to sea water for one year. The concrete cubes were prepared and subjected to water curing for 28 days before immersed in sea water. The compressive and flexural strengths of the specimens were tested at 3, 6 and 12 month following the procedures stated in BS 1881: Part 116 and ASTM C293-79 respectively. The study found that integration of POFA as partial cement replacement in aerated concrete enhances the performance of concrete in sea water environment

Mix design and compressive strength of geopolymer concrete containing blended ash from agro-industrial wastes

Geopolymer concrete is a type of amorphous alumino-silicate cementitious material. Geopolymer can be polymerized by polycondensation reaction of geopolymeric precursor and alkali polysilicates. Compared to conventional cement concrete, the production of geopolymer concrete has a relative higher strength, excellent volume stability and better durability. This paper presents the mix design and compressive strength of geopolymer concrete manufactured from the blend of palm oil fuel ash (POFA) and pulverized fuel ash (PFA) as full replacement of cement with a combination of sodium silicate and sodium hydroxide solution used as alkaline liquid. The density and strength of the geopolymer concrete with various PFA: POFA ratios of 0:100, 30:70, 50:50 and 70:30 together with sodium silicate to sodium hydroxide solution by mass at 2.5 and 1.0, are investigated. The concentrations of alkaline solution used are 14 Molar and 8 Molar. Tests were carried out on 100×100×100 mm cube geopolymer concrete specimens. Specimens were cured at room temperature and heat curing at 60°C and 90°C for 24 hours, respectively. The effects of mass ratios of PFA: POFA, the alkaline solution to PFA: POFA, ratio and concentration of alkaline solution on fresh and hardened properties of concrete are examined. The results revealed that as PFA: POFA mass ratio increased the workability and compressive strength of geopolymer concrete are increased, the ratio and concentration of alkaline solution increased, the compressive strength of geopolymer concrete increases with regards to curing condition

Palm oil fuel ash as the future supplementary cementitious material in concrete

The use of Palm Oil Fuel Ash (POFA) as a pozzolanic material for partial cement replacement in concrete reduces the cost of concrete as well as cuts down the number of landfill area required for disposing the ash. This paper presents a comprehensive review of the engineering properties and durability aspects of blended cement concrete incorporating POFA as a partial replacement of ordinary Portland cement (OPC). An Ordinary Portland Cement concrete mix termed P0 and two POFA concrete mixes with different fineness termed (POFA 45 and POFA 10) at 20% replacement level by weight of cement were considered in the study. Acid solution was found to be the most destructive under the applied exposure conditions on P0. The loss of mass and the resistance to chloride penetration were found to be depended on the degree of fineness of POFA to which the specimens were exposed. As for the values obtained from compressive strength test, P0 specimens were found to be the lowest compared with specimen consisting POFA. On the other hand, POFA 10 exhibited better resistance against acid than POFA 45. Conclusively, integration of POFA as partial cement replacement, especially very fine POFA increases the resistance of high strength POFA concrete towards both chloride attack and acid attack

Effect of Curing Regime on Compressive Strength of Aerated Concrete Containing Palm Oil Fuel Ash as Partial Sand Replacement

Issues on preservation of natural river sand from being used excessively in concrete industry has led to the efforts of utilizing palm oil fuel ash, a by-product from palm oil industry as partial sand replacement in production of aerated concrete. This paper reports the effect of curing regime on compressive strength development of aerated concrete containing palm oil fuel ash as partial cement replacement. Two types of mixes were used in this experimental work namely plain aerated concrete acting as control specimen and aerated concrete containing 30% palm oil fuel ash as partial sand replacement. Concrete cubes were subjected to different types of curing namely initial water curing for 7 days followed by air curing, water curing and air curing until the testing date. The compressive strength test was conducted in accordance to BS EN 12390-3 at 7, 14, 28 and 90 days. Application of water curing is the most suitable method to be applied to ensure better strength development in aerated concrete containing POFA as partial sand replacement. Continuous presence of moisture promotes better hydration and pozzolanic reaction leading to formation of extra C-S-H gel making the concrete denser and exhibit higher compressive strength

Chloride Resistance of Concrete Containing Palm Oil Fuel Ash

Experimental study was conducted to investigate the chloride resistance of concrete containing palm oil fuel ash (POFA). Ground POFA was used to partially replace Portland cement Type I, by 20% by weight of binder in order to prepare POFA concrete.  Water cement ratio of 0.28 was used and high water reducing admixture was added to maintain workability. POFA concrete was investigated and tested for compressive strength at ages of 7, 28 and 90 days. Rapid chloride penetration test (ASTM C1202) and salt ponding test (ASTM C1543) were conducted on standard concrete specimens to investigate the chloride resistance of concrete.  The results showed that the compressive strength of POFA concrete was improved comparing with plain concrete. The results of chloride penetration tests revealed that significant improvement in terms of chloride resistance could be obtained by using 20 % of ground POFA in concrete mix as cementing replacement material

Effect on compressive strength of epoxy-modified mortar with further dry-curing

The percentage of concrete porosity will affects the strength and performance of the concrete. It is believed that, with an additional curing, the porosity of the concrete becomes lower and the strength will increase. This paper presents a relationship between the strength development and porosity of epoxy-modified mortar. Epoxy-modified mortar is a type of polymer-modified which uses an epoxy resin without hardener as an addition material. Mortar specimens were prepared with a mass ratio of 1:3 (cement: fine aggregates), water-cement ratio of 0.48 and epoxy content of 5, 10, 15 and 20% of cement. The specimens were subjected to dry and wet-dry curing and the tests conducted were workability, setting time, compressive strength, flexural strength, tensile splitting strength, porosity and strength development. Results show that workability and setting time of the mortar decreased as epoxy content increased. Compressive, flexural and tensile splitting strengths of epoxy-modified mortar with wet-dry curing were significantly higher and became constant at 10% of epoxy resin content. A significant improvement in strength development of mortar without hardener was achieved even after 365 days of curing. The porosity of the mortar decreased as strength development increased. This was due to the gradual hardening reaction of epoxy resin with cement hydrates that filled the void inside; hence produced a denser and stronger mortar

Mechanical properties of self-compacting geopolymer concrete containing spent garnet as replacement for fine aggregate

Millions of tons of spent garnet, a by-product of surface treatment operations, are disposed of in landfills, oceans, rivers, and quarries, among others every year, thus it causes environmental problems. The main objective of this study is to evaluate spent garnet as a sand replacement in concrete prepared with ground granulated blast furnace slag (GGBS)-based self-compacting geopolymer concrete (SCGC). Concrete mixtures containing 0%, 25%, 50%, 75% and 100% spent garnet as a replacement for river sand were prepared with a constant Liquid/Binder (L/B) mass ratio equal to 0.4. Compressive, flexural and splitting tensile strengths as well as workability tests (slump, L-box, U-box and T50) were conducted on concrete containing spent garnet. As per specification and guidelines for self-compacting concrete (EFNARC) standard, the test results showed that the concrete’s workability increased with the increase of spent garnet, while all the other strength values were consistently lower than conventional concrete (SCGC) at all stages of replacement. The results recommended that spent garnet should be used in concrete as a sand replacement up to 25% to reduce environmental problems, costs and the depletion of natural resources

Effect of homogeneous ceramic tile waste on properties of mortar

The subject of reduce, reuse and recycle of waste material either from industrial or agricultural sectors is considered very important in the general attempt for sustainable construction. In relation to that, ceramic materials are widely used in many part of the world and consequently, large quantities of wastes are produced simultaneously by brick and tile manufacturers and construction industry. However, part of these wastes and those produced by the construction industry are dumped in landfills. In this present research, the effect of homogeneous ceramic tile waste on harden properties of mortar was investigated. Mortar mixes were prepared focusing on the effect of ceramic aggregates as river sand replacement. Tests were conducted for compressive strength, splitting tensile strength for all mortar specimens. The cement was partially replaced by ceramic powder by 20 %, 40 % and 60 %, respectively by weight of cement. The sand was replaced by ceramic aggregates ranging from 0% to 100% by weight of aggregates. The size of ceramic aggregates used is modified in accordance with ASTM C-33 while the cement was partially replaced by 40 % of ceramic powder by weight of cement. All specimens were cast in 50 mm cubes and cured in water after demoulding until the age of testing. By replacing 100 % of sand with ceramic aggregates, it was found that the compressive strength was very much similar to the control specimen without showing any negative effect. Similarly, by replacing cement with ceramic powder, the strength of mortar shows 10% increment as compared to control specimen. In conclusion, incorporation of homogenous ceramic tile waste either as sand replacement or cement replacement both can enhance the properties of mortar in fresh and hardened states

Synthesis and characterization of shelf-healing mortar with modified strength

Cementitious materials being the most prospective building blocks achieving their absolute strength to avoid the deterioration in the early stage of service life is ever-demanding. Minimizing the labor and capital-intensive maintenance and repair cost is a critical challenge. Thus, self-healing mortars with modified strength are proposed. Lately, self-healing of micro-cracks by introducing bacteria during the formation of mortar or concrete became attractive. Self-healing with polymeric admixtures is considered to be relatively more durable and faster process. Certainly, the self-healing of synthetic polymeric materials is inspired by biological systems, where the damage triggers an autonomic healing response. This emerging and fascinating research initiative may significantly improve the durability and the safety limit of the polymeric components potential for assorted applications. In this work, using epoxy resin (diglycidyl ether of bisphenol A) without any hardener as admixture polymeric-cementitious materials is prepared. These epoxy-modified mortars are synthesized with various polymer-cement ratios subjected to initial wet/dry curing (WDC) together with long term dry curing (DC). Their self-healing function and hardening effects are evaluated via preloading and drying of the specimens, chemical analysis, and ultrasonic pulse velocity testing. It is demonstrated that 10% of polymer is the best proportion for polymer-cement ratio. Furthermore, the wet/dry curing is established to be superior process for healing hairline cracks present in the mortar. The excellent features of the results suggest that our novel method may constitute a basis for improving the compressive strength and self-healing features of mortars

Properties of polymer modified mortars

The using of epoxy resin as repair material in concrete is quite common. Previous research proof that epoxy resin in concrete can give strength and have high durability towards aggressive environment. Usually epoxy resin needs a hardener to make it hard when mix with concrete but in this research, the development of concrete by using epoxy resin without hardener is investigate. Epoxy resin without hardener or can be known as epoxy-modified mortar also can mix well with cement and harden the concrete. This is due to the present of hydroxide ion in cement hydrate that can react with epoxy resin and make it harden. This paper is present a strength properties of epoxy-modified mortar up to three months. In this research an epoxy resins (Diglycidyl Ether of Bisphenol A) without any hardener is used as polymeric admixture to prepare polymeric-cementitious materials and their strength properties are analysed. Epoxy-modified mortars are prepared with various polymer-cement ratios, subjected to initial wet/dry curing plus long term dry. The optimum mix proportion of epoxy resin content in concrete is determined. The result shows that, the optimum polymer to cement ratio is 10% with dry/wet curing and up to three month of strength development, the compressive strength continuously increased