Effect of Non-Traditional Supplementary Cementitious Materials in Concrete

Fly ash, silica fume, metakaolin and ground granulated blast furnace slag, etc. have been established as traditional supplementary cementitious materials (SCM) and cement replacement materials; however, other alternate materials such as palm oil fuel ash (POFA), palm oil clinker powder (POCP), eco-processed pozzolan (EPP) and rice husk ash (RHA) have emerged as non-traditional materials that would take a role in replacing some of those established SCM. With a closure of most of the coal-operated power plants and imminent closure of more plants, the search for alternate materials is on the rise. Thus, it is mandatory for the researchers and cement manufacturers to invest more time and efforts to apply sustainable development goals (SDG) on the replacement of virgin materials to achieve low-carbon materials. The suitability and the effect of the above-mentioned non-traditional materials are detailed and discussed. The oxide composition, particle size and shapes through multiple tests and investigations are outlined. The plentiful availability of such non-traditional materials not only paves way for more research interest, but a genuine means of execution of plans to vigorously utilize those materials. The concrete quality on using such materials such as pore refinement, creation of additional C–S–H and dilution effects has been discussed

Development of lightweight concrete using industrial waste material, palm kernel shell as lightweight aggregate and its properties

Abstract-Agricultural industrial wastes produced after extracting palm oil from palm fruits known as palm kernel shell (PKS) are available in large quantities in Indonesia, Malaysia, Nigeria and other tropical countries. Malaysia is the second largest palm oil producing country in the world. This paper reports the results of an investigation conducted to utilize the PKS as lightweight aggregate to produce grade30 concrete with density of about 1850kg/m3. The properties of both PKS and crushed granite aggregates were compared. The concrete produced using PKS referred to here after as palm kernel shell concrete (PKSC) and its properties were compared with properties of normal weight concrete (NWC) of grade 30 produced using crushed granite aggregates. The fresh and hardened concrete properties such as density, workability, compressive strength of PKSC and NWC were compared. Further, structural behavior through flexural test was investigated. It has been found that PKSC has produced workable concrete and compressive strength of about 35MPa was obtained within 90 days. The addition of 10 silica fume has effect on both workability and strength. The as-cured density of PKSC was found 22 lower than the NWC. Further, the moment capacity of PKSC beams was found higher than NWC beams. In addition, the mode of failure observed in PKSC was ductile compared to the brittle failure of NWC beams

Feasibility study of high volume slag as cement replacement for sustainable structural lightweight oil palm shell concrete

This paper presents a study on the use of high volume slag as a cement replacement material, and waste oil palm shell (OPS) as a lightweight aggregate to produce a sustainable lightweight concrete (LWC). In order to establish the feasibility of such concrete for structural purposes, the first part of the paper deals with the investigation of the mechanical and bond properties of OPS concrete (OPSC) with varying slag content. The results showed that even though an increase in the slag content led to the reduction in the strength, the OPSC with slag as a 60 cement replacement material exhibited compressive and splitting tensile strengths of 25 and 2.3 MPa, respectively, which exceeded the minimum stipulated strength required for structural LWC. In addition, the use of 60 slag in OPSC showed significant benefits in terms of the reduced cement consumption with improvement in the strength efficiency by almost 2-fold compared to that without slag. On the other hand, it was found that the slag content, albeit as high as a 60 cement replacement level, did not show any significant adverse effects on the normalized bond strength, failure mode, bond strength-slip curve and slip at the ultimate bond strength of the OPSC. To further justify the suitability of the OSPC for structural application, the second part of the paper focuses on the experimental investigation of the flexural behaviour of the actual full-scale reinforced concrete beams. From the flexural tests, it was observed that there were no negative effects on the ultimate moment capacity, failure mode and moment-deflection behaviour of the reinforced concrete beams upon cement replacement with up to 60 slag. Therefore, the utilization of high volume slag-lightweight OPSC could be recommended for actual structural purposes. (C) 2014 Elsevier Ltd. All rights reserved

Effect of aggressive chemicals on durability and microstructure properties of concrete containing crushed new concrete aggregate and non-traditional supplementary cementitious …

The increasing awareness and usage of traditional supplementary cementitious materials (SCMs) in concrete have pressured the construction industry to look for alternatives to overcome the concerns over their plentiful availability in the future. This research illustrates the performance of recycled aggregate concrete prepared with the incorporation of available industrial by-products, namely rice husk ash (RHA), palm oil fuel ash (POFA) and palm oil clinker powder (POCP) as alternatives for traditional SCMs. The effect of hydrochloric (HCl) acid and magnesium sulfate (MgSO 4) attack was evaluated by measuring the change in mass, compressive strength and microstructural analysis. The results revealed that the incorporation of RHA, POFA and POCP up to 30% minimizes concrete deterioration and loss in compressive strength when the specimens were exposed to HCl solution. In addition, the scanning electron

Evaluation of industrial by-products as sustainable pozzolanic materials in recycled aggregate concrete

The utilization of traditional supplementary cementitious materials (SCMs) has become more intense in the concrete industry due to their better long-term properties. This research evaluates the fresh and hardened properties of concrete that was developed using a high amount of recycled aggregate (RA) incorporated with sustainable SCMs. Rice husk ash (RHA), palm oil fuel ash (POFA) and palm oil clinker powder (POCP) were used as SCMs at 10%, 20% and 30% cement replacement levels to investigate their positive role in the performance of RA concrete. The results showed that the 10% replacement level of cement by RHA produced the highest strength at all ages tested. Although POFA and POCP were found to negatively affect the strengths at an early age, the hardened properties showed improvement after a relatively long curing time of 90 days. In addition, the targeted compressive strength of 30 MPa was achieved by using SCMs at levels up to 30%. Overall, the sustainable SCMs can reduce the quantity of cement required for concrete production, as well as reduce the conventional cement with the industrial by-products, which are considered as waste materials; thus, the concrete produced using up to 30% of SCMs as a replacement for cement could be considered as more environmentally-friendly concrete

Assessment on engineering properties and CO2 emissions of recycled aggregate concrete incorporating waste products as supplements to Portland cement

This paper presents an experimental investigation on the durability properties and carbon dioxide (CO2) emissions of concrete developed using waste products. The concrete comprised of recycled concrete aggregate (RA) as a complete coarse aggregate replacement. In addition, rice husk ash (RHA), palm oil fuel ash (POFA) and palm oil clinker powder (POCP) were used as replacement materials for cement at levels up to 30%. The supplementary cementitious materials (SCMs) were used in RA concrete with the aim of reducing the dependency on cement as a stand-alone binder. The compressive strength, water absorption, chloride-ion penetration and electrical resistivity were investigated for RA concrete containing SCMs. Moreover, the residual compressive strength was also examined along with the weight loss to check the elevated temperature resistance of RA concrete with SCMs. The results revealed that

Ductile behaviour of oil palm shell concrete slabs subjected to blast loads

Oil palm shell (OPS) is an industrial waste material abundantly available in Malaysia and other South East Asian countries. It has high aggregate impact resistance characteristics and hence its capability to withstand blast load was tested through OPS concrete (OPSC) slabs designed and developed in University of Malaya, Kuala Lumpur, Malaysia and tested at Huluduo, China. LVDTs, pressure transducers and accelerometers were used to record data of response of the slabs subjected to quasi-static load and blast loads of 1, 5 and 10 kg TNT. The recorded data were then analysed and compared and conclusions were made on the effectiveness of OPS as a coarse aggregate. It has been found that OPSC outperformed normal concrete (NC) slab when subjected to 10 kg TNT as OPSC panel was intact and had no shrapnel; the ductility behaviour of OPSC, it exhibited multiple cracks and the impact resistance of OPS through its energy absorption due to fibrous content within OPS itself was visible both in crack pattern and in its propagation. Though OPS is of organic nature, its resistance to blast waves was observed as the huge fire ball created due to blast had no or little effect on the OPSC panels

Shear strength of oil palm shell foamed concrete beams

Four reinforced oil palm shell foamed concrete (OPSFC) beams were fabricated, and their shear behaviour was tested. The OPSFC has a target density of approximately 1600 kg/m(3) and a 28-day compressive strength of about 20 MPa. Two beams were cast with shear reinforcements while the other two were cast without such reinforcements. For comparison, four reinforced normal weight concrete (NWC) beams were also cast. The beams that contained shear links failed in flexure mode, while those without links failed in shear mode. The experimental results indicated that the shear capacities of OPSFC beams without shear links are higher than those of the NWC beams and exhibit more flexural and shear cracks

Influence of fibers on bond strength of concrete exposed to elevated temperature

Concrete is a building material having good fire resistance and the resistance depend on many factors including the properties of its constituent materials. Fiber Reinforced Concrete (FRC) apart from improving mechanical properties has better fire resistance than conventional concrete. Bond strength of concrete is one of the important properties to be considered by structural engineers while designing reinforced concrete cements. In this research, an experimental investigation has been carried out to determine the effect of fibers on the bond strength of different grades (M20, M30, M40 and M50) of concrete subjected to elevated temperature. Different types of fibers such as Aramid, Basalt, Carbon, Glass and Polypropylene were used in the concrete with a volume proportion of 0.25% to determine the bond strength by pull-out test. Prior to the pull-out test, the specimens were kept in a furnace and subjected to elevated temperatures following standard fire curve as per ISO 834. Based on the test results of the investigations, type of fiber, grade of concrete and duration of heating were found to be the key parameters that affect the bond strength of concrete. The contribution of carbon fiber in enhancing the bond strength was found to be more significant compared to other fibers. An empirical relationship has been developed to predict the bond strength of FRC at a slip of 0.25 mm. This empirical relationship is validated with experimental results. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group