Zamin Jumaat

• BSc.. MSc, PhD
• Head of Department at University of Malaya

Reinforced concrete (RC) infrastructure is an essential part of modern civilization. However, the serviceability of RC infrastructure in extreme weather has become challenging due to the susceptibility of the initiation of cracks. Hence, the demand for strengthening and retrofitting RC infrastructure is rapidly increasing. The RC specimens strength...

The strengthening of the reinforced concrete (RC) elements enhances their strength, stiffness, ductility, and durability. This study examined the efficiency of the Side-Near-Surface-Mounted (SNSM) technique over the Near-Surface-Mounted (NSM) technique for RC beams. Utilized Glass Fiber Reinforced Polymer (GFRP) composite as a strengthening reinfor...

The performance of reinforced concrete (RC) beam specimens strengthened using a newly proposed Side Near Surface Mounted (S-NSM) technology was investigated experimentally in this work. In addition, analytical and nonlinear finite element (FE) modeling was exploited to forecast the performance of RC members reinforced with S-NSM utilizing steel bar...

Self-compacting concrete (SCC) is a type of concrete with low flow resistance that may be cast and compacted by its own weight without the need for external vibration, bleeding, or segregation during the casting process [1, 2]. SCC saves costs by decreasing construction time, equipment, and expert personnel needs due to its ease of placement. Also,...

Cementitious coating is essential as passive protection for building and infrastructure including steel and coastal structures from aggressive environment, such as fire and chloride and enhance the durability of the substrate. Still, there is durability concern on the conventional ordinary Portland cement (OPC)-based coatings that will lead to high...

To limit the cross-sectional size of concrete structures, high-strength, lightweight concrete is preferred for the design and construction of structural elements. However, the main drawback of high-strength, lightweight concrete is its brittleness over normal-weight concrete. The ductility of concrete is a crucial factor, which plays an important r...

To limit the cross-sectional size of concrete structures, high-strength, lightweight concrete is preferred for the design and construction of structural elements. However, the main drawback of high-strength, lightweight concrete is its brittleness over normal-weight concrete. The ductility of concrete is a crucial factor, which plays an important r...

Enunciation of the embryonic materials from industrial by-products is vital to address the ever-depleting virgin construction materials. The palm oil clinker (POC) is one of the industrial by-products from the palm oil industries available in abundance in Southeast Asia. POC is lightweight, and porous and hence, it is considered as a potential ligh...

In this study, a combined strengthening technique is used to improve the flexural performance of prestressed concrete beams using CFRP sheets as EBR and prestressed steel strands as NSM. Seven prestressed beams were tested under four-point loading with one control specimen, one EBR CFRP sheet strengthened specimen, one NSM steel strand without pres...

The application of waste materials in the concrete composite is a great contribution to preserving natural resources and enhancing sustainable greener development in the construction industry. This study used Palm Oil Clinker (POC) and steel fibers to manufacture high strength lightweight concrete (HSLWC). The byproduct (POC) of a palm oil industry...

Masonry buildings are in great demand in developing countries due to the need for sustainable and affordable housing. However, increased materials costs and carbon emissions associated with the production and use of conventional masonry products and need for higher standard of living have led to a steady increase in embodied energy use and costs of...

Reinforced concrete (RC) structures necessitate strengthening for various reasons. These include ageing, deterioration of materials due to environmental effects, trivial initial design and construction, deficiency of maintenance, the advancement of design loads, and functional changes. RC structures strengthening with the carbon fiber reinforced po...

One solution to the high cost and scarcity of building materials is to use alternative and sustainable materials. The study presented herein developed an eco-friendly masonry grout using high volumes of palm oil clinker powder to replace cement and palm oil clinker to replace coarse aggregate. Several batches of grouts with different amounts of the...

Masonry blocks are extremely popular for a wide range of masonry structures around the world. However, the ever-increasing cost of materials and overexploitation of natural resources in the production of blocks pose grave environmental concerns. Three waste materials and industrial by-products from the palm oil and steel industries, namely, palm oi...

The efficacy of two palm oil industrial waste materials, namely palm oil fuel ash (POFA) and oil palm shell (OPS), as partial and whole replacement materials, respectively, for ordinary Portland cement (OPC) and conventional crushed granite aggregate on fresh and hardened concrete properties has been investigated and reported. OPC was partially rep...

The efficacy of two palm oil industrial waste materials, namely palm oil fuel ash (POFA) and oil palm shell (OPS), as partial and whole replacement materials, respectively, for ordinary Portland cement (OPC) and conventional crushed granite aggregate on fresh and hardened concrete properties has been investigated and reported. OPC was partially rep...

This study investigates the performance of a specific beam-to-column connection using partly hidden corbels with different anchorage arrangements in precast concrete structures. Full-scale testing is conducted on two precast concrete exterior beam-to-column connections to determine their suitability as semi-rigid and partial-strength connections. T...

Infrastructures such as bridges are often susceptible to continuous cyclic loadings and exposed to structural vibration. The cumulative cyclic loads will lead the structures into fatigue condition and contribute to the deficient service life of structures. Hence, evaluating the current structural health condition through the structural stiffness qu...

Structural strengthening comprises modification of the structural elements to enhance their load bearing capability, stiffness, toughness, and ductility. The present study is an experimental investigation on the performance of reinforced concrete (RC) beam specimens strengthened by the side near surface mounted (SNSM) technique with reinforcement s...

Although many countries have the wish to assess the social impact, it is not clear how to evaluate societal quality, exclusively for basic and strategic research. Another side, it is very essential for a young researcher, engineers and scientists to understand the importance of societal impact for research. The major contribution to infrastructure...

The strengthening reinforcement is glued to the soffit of the reinforced concrete (RC) beams in the mainstream externally bonded reinforcement (EBR) technique for flexural strengthening. However, the soffit of RC beams could be inaccessible for strengthening due to limited or no space at the soffit because of walls or doors, or the spalling of conc...

This study presents the segregation resistance of SCC incorporating palm oil fuel ash (POFA). Twenty SCC mixtures were produced based on the water/binder (W/B) ratios of 0.25-0.40 and incorporating 0-30% POFA by weight of cement. The segregation resistance of the SCC mixtures was examined by sieve and column segregation tests with respect to segreg...

This paper presents the investigation of the strength characteristics and microstructural analysis of cement composite mortar developed using nontraditional cement replacement materials. Three types of materials, namely palm oil fuel ash (POFA), treated palm oil fuel ash (TPOFA), and bottom ash (BA) were used as partial cement replacement materials...

The Editor-in-Chief has retracted this article (Naji et al. 2016a) because validity of the content of this article cannot be verified. This article showed evidence of substantial text overlap (most notably with the articles cited (Naji et al. 2014, 2016b; Akib et al. 2015)), peer review and authorship manipulation.

The rapid depletion of natural resources has led to the need to develop sustainable practices and material in various applications. One such sustainable practice is to divert the waste generated in the palm oil industry into production of building materials. In this study, palm oil clinker (POC) is used to replace cement and coarse aggregate. The P...

Bridge reinforced concrete deck slabs are often subjected to various cyclic loadings—making regular checks for fatigue damage necessary. Several experiments on reinforced concrete structures were conducted to evaluate its mechanical fatigue behaviour. Nevertheless, adequate experimental investigations on its dynamic properties are still needed. Thi...

The performance of high strength structural lightweight concrete (LWC) using the palm wastes, oil palm shell (OPS) as well as palm oil clinker (POC) has been reported. Existing literatures used either OPS or POC individually for production of LWC. Each concept has their own advantages-disadvantages. In this study, both OPS and POC have been put tog...

Masonry and rendering mortars are is well known oldest techniques in the building. A common idea is to use strong material as possible, and as a result mortars are often rich in cement. Not only this is unnecessary expensive, it has also technical disadvantages and harmful to environment. Hence, in this study focuses on utilisation of palm oil mill...

Drying shrinkage in concrete can be attributed to loss of moisture, variations in temperature, and the chemical reactions of cement with water and carbon dioxide, is one of the most important parameters which affects the durability and service life of the concrete structures. Recently, the lightweight concrete has got a considerable attention to be...

The utmost priority in reducing the usage of ordinary Portland cement (OPC) while replicating the cementitious properties by utilizing industrial by-products in construction materials is seriously undertaken by many researchers. The technology of geopolymerization that utilizes materials and activator solution to form geopolymer matrix could lead t...

Rapid growth in population and urbanization the world faced challenges in three dimensions includes economic, social and environmental. Research has led to new findings on these challenges, but these are still very rarely used, predominantly in Asia. The major reasons for this are that people assume such alternatives are not easily available in the...

Inadequate supply of affordable housing for growing population in Malaysia have influenced on rapid increase in construction activities. Therefore, adopting alternatives to meet the challenge of bridging the affordability gap is significant. On the other side, the Malaysia produces huge waste and on average throws away 1.64 kg of municipal solid wa...

The use of eco-efficient building materials in construction has become a trend in regard to the effort of mitigating the effect of global warming which include CO2 emission, energy demand, and natural resources depletion that lead to negative environmental impacts. The present study was attempts to investigate the microstructure behaviour and durab...

In recent decades, the application of carbon fibre-reinforced polymer (CFRP) composites for strengthening structural elements has become an efficient option to meet the increased cyclic loads, or repair due to fatigue cracking. The premature failure due to end-debonding is a key limitation to achieve high fatigue performance of strengthened steel b...

For long, the growing amount of solid wastes from various industries has created disposal issues and caused serious environmental concerns. Increased efforts have been carried out to recycle and valorize the industrial wastes into use as concrete-making materials. Due to the current growth of construction industries around the world, natural sand i...

Masonry and rendering mortars are is well known oldest techniques in the building. A common idea is to use strong material as possible, and as a result mortars are often rich in cement. Not only this is unnecessary expensive, it has also technical disadvantages and harmful to environment. Hence, in this study focuses on utilisation of palm oil mill...

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 (P...

This paper presents the durability indicators for sustainable self-consolidating high-strength concrete (SCHSC) including palm oil fuel ash (POFA) as a supplementary cementing material (SCM). SCHSC mixes were prepared by varying the water to binder (W/B) ratio and POFA content. The W/B ratio was varied in the range of 0.25 to 0.40, and the POFA con...

Fiber Reinforced Polymer (FRP), which has a high strength to weight ratio, are now regularly used for strengthening of deficient reinforced concrete (RC) structures. While various researches have been conducted on FRP strengthening, an area that still requires attention is predicting the debonding failure load of prestressed FRP strengthened RC bea...

Cement-lime based mortar is extremely popular for a wide range of construction around the world and conserving natural resources used in the production of such material is of capital importance. Identification of alternative materials from palm oil based industrial by-products enabled researchers to use palm oil clinker powder (POCP) as a cement re...

Side Near Surface Mounted (SNSM) strengthening technique is among the latest technique introduced recently. In this paper, SNSM carbon fiber reinforced polymer (CFRP) strips strengthening technique is proposed for enhancing the flexural performance of reinforced concrete (RC) beams. A total of seven RC beam specimens were tested: one un-strengthene...

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...

In order to reduce the dependency on virgin materials for construction, efforts have been made to incorporate by-products and wastes from different industries as alternatives in concrete. Originating from the fishery industry, seashell waste, such as oyster shells, mussel shells, and scallop shells, among others, is available in huge quantities in...

Various advanced floating structures were proposed and developed till date due to their cost effectiveness and productiveness in deep and ultra-deep water exploration. Spar has been seen as a latest and productive alternative amongst the all type of floating offshore platform. However, the precise behavior of fully coupled action of the platform in...

Several advanced floating structures have been proposed and developed with varying cost effectiveness and productiveness in deep water exploration. Among them, Spar platforms have been accepted as an efficient platform for the exploration. Many research works have been conducted on floating structure but a few on Spar platform. Nonlinear dynamic an...

The influence of fiber on the mechanical properties and impact resistance of oil palm shell geopolymer concrete (OPSGPC) prepared with ground granulated blast-furnace slag (GGBS) and palm oil fuel ash (POFA) as binders is reported. The mechanical properties of OPSGPC, namely compressive, flexural, splitting tensile strengths, and modulus of elastic...

Reinforced concrete (RC) beams strengthened with fiber reinforced polymer (FRP) have been extensively investigated, but the failure load of precracked beams strengthened with FRP has not been fully studied yet. When structurally deficient RC beams are repaired or strengthened using FRP, flexural cracks due to service load usually appear on the beam...

Reinforced concrete (RC) infrastructures often require strengthening due to error in design, degradation of materials properties after prolong utilization and increases load carrying capacity persuaded by new use of the structures. For this purpose, a newly proposed Side Near Surface Mounted (SNSM) composite technique was used for flexural strength...

The summary of developments in partially replaced cement composite and geopolymers by industrial by-products are presented along with different nano-materials. Many significant correlations have been studied on association with the better understanding of the interfacial transition zone, microstructural performance, mix design characteristics, sett...

The shear behaviour and mechanical properties (compressive, splitting tensile and flexural strengths) as well as the flexural toughness of steel fibre-reinforced cement-based and geopolymer oil palm shell lightweight aggregate concrete (OPS LWAC) were experimentally investigated in this paper. Steel fibres were added at various volume fractions for...

Structural lightweight concrete plays an important role in the construction industry, especially for the high-rise buildings. It can only be produced using lightweight aggregates. Oil-palm-boiler clinker (OPBC) is a solid waste from the oil palm industry and could be used as lightweight aggregate in concrete mixture. However, the density of this li...

This article presents a comparison of the bond behaviour between palm oil fuel ash (POFA)-derived geopolymer and conventional cement-based normal weight and lightweight concretes. A total of 16 variables were tested, which includes concrete cover (50 and 100 mm), bar diameter (12 and 16 mm) and types of concrete (POFA-based geopolymer normal/ light...

In this paper, the effects of lateral bracing and web stiffeners on the Carbon Fibre Reinforced Polymer (CFRP) failure modes and buckling strength of the CFRP strengthened wide-flange steel I-beams are investigated experimentally. The study consisted of eight beams tested under static gradual load until failure. The main test variables were steel p...

Reinforced concrete (RC) structures require strengthening for numerous factors, such as increased load, modification of the structural systems, structural upgrade or errors in the design and construction stages. The side near-surface mounted (SNSM) strengthening technique with glass fiber-reinforced polymer (GFRP) bars is a relatively new emerging...

Huge demand for concrete due to industrialization and urbanization has resulted in the depletion of natural resources and led to an ecological imbalance. Hence, this research focuses on alternative materials, including the utilization of waste materials as a replacement for binders and conventional aggregates. Palm oil fuel ash (POFA), ground granu...

Recent trend is to use the lightweight concrete in the construction industry because it has several advantages over normal weight concrete. The Lightweight concrete can be produced from the industrial waste materials. In South East Asian region, researchers are very keen to use the waste materials such as oil palm shell (OPS) and palm oil clinker (...

The benefits of using structural lightweight concrete in construction industry, particularly in high rise buildings, over normal weight concrete are numerous. The main method of producing structural lightweight concrete is the use of lightweight aggregates instead of ordinary aggregates in concrete. Due to the limited resources for natural and arti...

In the effort of developing sustainable concrete, studies on the replacement of conventional coarse aggregates with local waste material are increasing. The new oil palm shell fibre-reinforced concrete (OPSFRC) utilises Malaysia’s waste material and is emerging as a promising sustainable concrete attributed to its lightweight and enhanced concrete...

Huge amount of virgin materials is being used in the production of concrete and the negative impact caused by exploitation of natural resources to our eco-system is beyond recovery. In order to produce a cleaner and greener concrete, waste palm oil clinker (POC) powder, a by-product from palm oil industry was used as filler and amorphous material i...

Spar platform is a type of floating structure utilized for oil and gas exploration and production in deep and ultra-deep waters. Coupled analysis in present study considers Spar mooring lines as an integrated system. It incorporates the contribution of drag and inertia forces of mooring lines. A rigid classical Spar cylinder connected by four tensi...

This paper presents an experimental investigation of the mechanical, toughness, bond and some durability-related properties of oil palm shell lightweight concrete (OPSC) containing up to 1.0 % steel fibres. While the inclusion of up to 1.0 % steel fibres gave enhanced tensile and bond strength as well as toughness to the OPSC, little influence was...

This paper presents a generalized formulation for optimizing the design of concrete beam reinforced with glass fiber reinforced polymer bar. The optimization method is formulated to find the design variables leading to the minimum weight of concrete beam with constraints imposed based on ACI code provisions. A simple genetic algorithm is utilized t...

Fibre reinforced polymers (FRP) has been widely applied to strengthen reinforced concrete (RC) beams due to its high strength and low weight. However, despite widespread use and various researches on FRP strengthening, the problem of premature failure is still a concern. The present work aims to contribute to the current research on preventing prem...

This study examines the structural performance of beam end connectors used as connection device in semi-rigid boltless beam-to-column connections (BCCs) in steel pallet racks (SPRs). A total of six types of specimens were tested which were distinguished by the three different types of beam end connector (BEC) thicknesses and two different numbers o...

The utilization of palm-oil-fuel-ash (POFA), fly-ash (FA), and blast-furnace-slag (BFS) as binders and the effects of quarry dust and manufactured sand (M-sand) as replacement for conventional mining sand (N-sand) on compressive strength (fcomp) of geopolymer mortar were investigated. The calcium rich-BFS increased fcomp and 50% POFA with BFS produ...

In this study, a multi-layered steel reinforced composite beams which are composed of geopolymer concrete section at tensile zone and Portland cement based concrete at compression are investigated. The beams were tested to failure to compare the toughness, post peak behaviour and failure mode based on the variation of the depth of layers. The mecha...

This paper presents the investigation of the properties of polymer fibre-reinforced high volume palm oil fuel ash (POFA) blended mortar. Considering the targeted application for non-structural building material, the thermal conductivity, compressive and residual strengths as well as the water absorption of the mortars were evaluated. The incorporat...

Prestressing of strengthening materials can enhance the performance of strengthened structures as the materials become more efficient as a greater portion of their tensile capacity is employed. Prestressed concrete beams are widely used in the construction field, however, there is a lack of studies on the strengthening of these structural elements....

This paper presents the investigation on the local bond stress-slip behaviour of lightweight oil palm shell concrete (OPSC). The bond properties of the OPSC specimen with varying reinforcing bar diameters (12 and 16 mm), concrete cover sizes (50, 75 and 100 mm) and compressive strengths (25 and 35 MPa) were explored. A concrete cover size to reinfo...

The use of structural lightweight aggregate concrete in structures has several benefits over normal weight concrete, particularly in multi-story buildings. The best way to produce structural lightweight concrete is by using lightweight aggregates. The use of artificial aggregates was minimized because of the high production costs due to huge consum...

The side near-surface mounted (SNSM) method is an alternative method used for applying fibre reinforced polymer (FRP) flexural strengthening on reinforced concrete (RC) beams. The SNSM method places the FRP grooves at the sides of the beam, rather than at the bottom in the normal near surface mounted (NSM) method. This research focuses on studying...

The near surface mounted (NSM) technique for strengthening reinforced concrete (RC) beams normally utilizes fibre reinforced polymer (FRP) bars or strips placed within grooves made on the soffit of the beams. For RC beams strengthened with NSM the failure mode would normally be the premature debonding failure by separation of concrete cover. A few...

In this paper, the effect of partial replacement of cement with metakaolin (MK) on the strength properties of oil palm shell (OPS) lightweight concrete was investigated. Generally, 5–20% of partial cement replacement with MK enhanced the compressive, splitting tensile and flexural strengths as well as modulus of elasticity of OPS concrete (OPSC). T...

This article presents the development of lightweight-foamed concrete with geopolymer technology by utilizing industrial wastes such as oil palm shell (OPS) as lightweight coarse aggregate, palm oil fuel ash (POFA) and low calcium fly ash (FA) as binders in the concrete. The main aim of this research is the assessment of morphology and mineralogy on...

The flexural behaviour of strengthened reinforced concrete (RC) beams is more complicated compared to the normal beams due to the different bond conditions and properties of the externally bonded material. A significant number of research studies have been reported on the use of different types of material for flexural strengthening of RC beams usi...

The energy absorption capacity of reinforced concrete (RC) elements is one of the crucial structural properties that define their seismic resistance. The use of steel bars for the strengthening or retrofitting of RC beams in view of their superior mechanical behaviour, is predominantly motivated by their energy absorption capacity. This paper prese...

This study investigates the flexural behaviour of reinforced concrete (RC) beams strengthened through the combined externally bonded and near-surface mounted (CEBNSM) technique. The externally bonded reinforcement (EBR) and near-surface mounted (NSM) techniques are popular strengthening solutions, although these methods often demonstrate premature...

Huge amount of palm oil wastes were produced annually in Malaysia, among these are oil palm shell (OPS) waste and palm oil fuel ash (POFA). OPS is a waste obtained after the palm oil extraction process while POFA is a resulting waste from the incineration process of OPS along with other palm oil wastes such as palm oil fibre and empty fruit bunch....

Palm oil fuel ash is an supplementary cementitious material (SCM) generated from the combustion of palm oil fibers and shells in palm oil mills to produce electricity, and One approach to reduce the carbon dioxide emissions and increase the sustainability of concrete by substitute a significant amount of ordinary Portland cement (OPC) with it. This...

As a ceramic-like material, geopolymers show a high quasi-brittle behavior and relatively low fracture energy. To overcome this, the addition of fibers to a brittle matrix is a well-known method to improve the flexural strength. Moreover, the success of the reinforcements is dependent on the fiber-matrix interaction. In this present study, effects...

Concrete industry is one of the major sources of consuming high volume of natural resources. On the other hand, cement industry is a significant point source of carbon dioxide emissions due to the decomposition of raw material and burning fuel during the manufacturing process. As the demand for concrete is growing, one of the effective way to minim...

Structures that susceptible to continuous cyclic loads such as bridges will experience fatigue. Therefore the importance and the need to make a continuous structural health monitoring on the existing bridge structures, so it can be function safely. Static tests are often used to determine the current capacity of the bridge structure. However, this...

Modeling is a very useful method for the performance prediction of concrete. Most of the models available in literature are related to the compressive strength because it is a major mechanical property used in concrete design. Many attempts were taken to develop suitable mathematical models for the prediction of compressive strength of different co...

This article reports investigation carried out using high volume palm oil fuel ash (POFA-90%) based geopolymer concrete using oil palm shell (OPS) as coarse aggregate. The tensile and fracture properties of OPS based lightweight geopolymer concrete (OPSGC) with the addition of steel fibres (SF) of two aspect ratios (AR80, AR65) and three volume fra...

Describing the moment rotation (M/θ) behavior of reinforced concrete (RC) hinges is essential in predicting the behavior of RC structures under severe loadings, such as under cyclic earthquake motions and blast loading. The behavior of RC hinges is defined by localized slip or partial interaction (PI) behaviors in both the tension and compression r...

This paper introduces an innovative approach, referred to as the Side Near-Surface Mounted (S-NSM) technique, for flexural strengthening of reinforced concrete (RC) beams using Carbon Fibre-Reinforced Polymer (CFRP) bars. Experimental and analytical investigations were conducted to explore the strengthening of RC beams with S-NSM CFRP bars. Analyti...