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Application of Clam (lokan) Shell as Beach Retaining Wall
Abstract
This project is about investigating the possibility of using the local clam (lokan)l embedded in the concrete as beach retaining wall. Since the shell is considered as undesirable product and normally disposed in open area, the researchers taking this opportunity to determine the possibility of lokan shell powder as the alternative fine aggregate to increase the compressive strength of the concrete. From the compression test, by embedding lokan powder into the concrete, it can increase the compressive strength up to 16% (at 30 wt% of lokan powder) compared to concrete without lokan powder. Thus, it can be concluded that lokan powder which is waste material has high potential as the alternative fine aggregate to improve strength of the concrete and can be applied as a retaining wall. I. INTRODUCTION etaining wall is a structure that is designed to oppose the lateral pressure of soil when there are some changes in ground elevation that exceeds the slope of repose the soil. For beach retaining wall, its main function is to separate the retained soil from being struck by strong wave from the sea and thus, avoid the erosion along the coastline. According to the Annual Report, department of Irrigation and Drainage (DID Malaysia, 2007), about 1415 km out of 4809 km of Malaysia " s coastline is subjected to erosion of different degree of harshness. Besides, the water level increased during the monsoon period and the wave produced will breaks directly against the fragment that causing the loss of materials. This has forced society to take urgent action to commence coastal erosion protection by using bulky construction such as concrete. Retaining walls serve to retain the lateral pressure of soil. In this case, for beach retaining wall, the wall is not only subjected to the pressure from the soil but also the sea water and the sea wave. For this purpose the selection of the type of the retaining wall and the materials (including the concrete) is very important. However, for this study, the only point to be concentrated is to improve the compressive strength of the concrete that can be applied to build up the retaining wall. The researchers assume that the best selected
... Some studies subjected the seashells to elevated temperatures at varying durations in order to dehydrate and disinfect the shells. Such seashells were oven-dried at 50°C for 24 h [55], 105°C for 4 h [6], 110°C for 24 h [51,50,9] or 135°C for 30 min [31]. It is useful to note that although the heating process kills bacteria in seashells, energy is expended when oven-drying the shells especially for longer heating durations. ...
... Generally, seashells utilised as fine aggregate were crushed and sieved to sizes below 5 mm. Yusof et al. [55] used crushed clam seashells passing through 500 lm as partial replacement of fine aggregate. Different types of crushing device, like, jaw crusher [51,50,33], drum compactor [10] and hammer [49] were used to grind the seashells. ...
... Sources for clam shell: [24,28,41]. Concrete mixes which contain smaller-sized seashell grains generally show higher compressive strength [55,25]. This can be attributed to lower void content and better aggregate-paste bond. ...
Trends in concrete technology are currently directed towards sourcing alternative sustainable materials for concrete in order to minimise over-reliance on natural resources. Many of the substitute materials used for producing green concrete are recycled materials obtained from industrial wastes and by-products. A promising solution to the challenge of seashell waste management involves utilising seashells as construction materials in concrete. Experimental investigations have been carried out on the use of mollusc seashells such as periwinkle shell, mussel shell, oyster shell, cockle shell, crepidula shell, clam shell and scallop shell as aggregate replacement materials in concrete. The seashells were utilised as partial or total replacement of fine and coarse aggregates in concrete. This paper is a literature review of seashell aggregate concrete. The paper first presents an overview of the physical, mechanical and chemical properties of the seashells. This is followed by a discussion of the physical, mechanical and durability properties of seashell aggregate concrete in fresh and hardened states. Possible applications in the construction industry are also highlighted. Mollusc seashells have similar chemical composition with limestone-type aggregates but characteristically contain traces of chloride and sulphate salts. Although inclusion of seashell aggregate reduces the physico-mechanical properties of concrete, utilising some seashells as partial coarse aggregate at up to 50% substitution level can produce normal-weight concrete for non-structural and low-strength structural functions. The current understanding of seashell aggregate concrete provides a basis for further research on various aspects of its behaviour including the sound absorption and thermal insulation properties.
... Agbede and Manasseh (2009) heat-treated periwinkle shells at 105°C for 4 h to determine the aggregate impact value test. Other mollusc seashells utilised in concrete have been heat-treated for varying durations and temperatures (Barbachi et al., 2017;Martínez-García et al., 2017;Yang et al., 2010;Yusof et al., 2011). Heat treatment of seashells helps to improve the shell quality through dehydration and disinfection as well as safe handling and storage (Martínez-García et al., 2017;Yang et al., 2010). ...
... The possibility of utilising crushed periwinkle shell in very fine powdered form as partial replacement of cement, sand, or both (i.e., using periwinkle shell powder as an SCM or a filler) in Portland cement-based construction materials should be explored. Similar attempts have been made using mollusc shell powder from certain seashells as partial replacement materials in Portland cement-based products(Binag, 2016;Lertwattanaruk et al., 2012;Olivia et al., 2015Olivia et al., , 2017Yusof et al., 2011). There is dearth of literature on the performance of periwinkle shell powder in cement-based materials.9 ...
... Agbede and Manasseh (2009) heat-treated periwinkle shells at 105°C for 4 h to determine the aggregate impact value test. Other mollusc seashells utilised in concrete have been heat-treated for varying durations and temperatures (Barbachi et al., 2017;Martínez-García et al., 2017;Yang et al., 2010;Yusof et al., 2011). Heat treatment of seashells helps to improve the shell quality through dehydration and disinfection as well as safe handling and storage (Martínez-García et al., 2017;Yang et al., 2010). ...
... The possibility of utilising crushed periwinkle shell in very fine powdered form as partial replacement of cement, sand, or both (i.e., using periwinkle shell powder as an SCM or a filler) in Portland cement-based construction materials should be explored. Similar attempts have been made using mollusc shell powder from certain seashells as partial replacement materials in Portland cement-based products(Binag, 2016;Lertwattanaruk et al., 2012;Olivia et al., 2015Olivia et al., , 2017Yusof et al., 2011). There is dearth of literature on the performance of periwinkle shell powder in cement-based materials.9 ...
Periwinkle shellfishes are widely distributed in the wetlands of the
Niger Delta. Periwinkle shells are often heaped in open fields and landfills which cause environmental problems such as pollution and breeding of disease-carrying organisms. In order to manage periwinkle shell by-products, preserve natural resources and save construction costs, attempts have been made to use periwinkle shell aggregate (PSAGG) and periwinkle shell ash (PSASH) as recycled materials in cement-based products. This paper reviews the influence of PSAGG and PSASH on the properties of Portland cement-based materials. Periwinkle shell has similar calcium carbonate content with limestone aggregate. Using PSAGG as a partial coarse aggregate at up to 50% replacement level can produce normal-weight concrete which possesses over 60% of the control strength. Utilising PSASH as a supplementary cementitious material (SCM) will have beneficial functions in cement-based construction where low heat of evolution is needed and early strength is not a major consideration. Further investigations are required including in-depth research on the cost analysis and durability of cement-based products containing periwinkle shell by-products.
... [9-10] found that the specific gravity of oyster is different which is 3.09, 2.65 and 2.33. But, this value is below than the Portland cement which was 3. 15[9] and 3.11 [8]. Also, from the table it can be concluded that the specific gravity value of oyster shell is 2.33 and it was the most suitable to be used as cement replacement compare to other seashells. ...
... Table 5 shows a few types of seashell and how it was used in concrete mixture. [11,12,14] and [15] used different types of seashell to replace the coarse or fine aggregate in the concrete in range of 5% to 50% and found out that the compressive strength increased significantly. [13] had used oyster shells ashes to replace lime in production of cement based brick. ...
This review paper emphasis on various sea shells ash such as cockle, clam, oyster, mollusc, periwinkle, snail, and green mussel shell ash as partial cement replacement and its objective is to create sustainable environment and reduce problems of global warming. Cement production give huge impact to environment in every stage of its production. These include air pollution in form of dust and, gases, sound and vibration during quarry crushing and milling. One of the solutions to solve this problem is by using modified cement. The modified cement is a cementitious material that meets or exceeds the Portland cement performance by combining and optimizes the recycle and wasted materials. This will indirectly reduce the use of raw materials and then, become a sustain construction materials. Therefore, the replacement of cement in concrete by various sea shell ash may create tremendous saving of energy and also leads to important environmental benefits. This study includes previous investigation done on the properties of chemical and mechanical such as specific gravity, chemical composition, compressive strength, tensile strength and flexural strength of concrete produced using partial replacement of cement by seashells ash. Results show that the optimum percentage of seashells as cement replacement is between 4 – 5%.
... Snail and Clam are small marine animals belonging to the group phylum Mollusca and class gastropod [1]. Their shells are produced as waste materials from the local consumption of these animals and also from food industries. ...
... Research has been carried out on the Strength Characteristics of Snail Shell Ash Blended Cement Concrete [10] [11], snail shells has been used in cement mortars for masonry and plastering [12]. Research has also been carried out on clam shells as beach retaining wall [1]. Research has shown that Clam shell is richer in micro-nutrients compared to land snail, water snail and periwinkles shells [13]. ...
... Elongated and flaky aggregates possess an insufficient bond with the paste of cement and form more voids inner the concrete structure, thus a reduction in compressive strength [17, 11, 8, 18. 19]. Concrete mixtures incorporating smaller-sized seashell particles commonly reveal greater compressive strength [20,11]. This growth in compressive strength can be referred to descending voids range and adequate aggregate-paste bond. ...
Waste Recycling Is Essential Economically And Environmentally. The Principal Purpose
... The current processing methods for seashell materials are mainly rinsing, drying or calcination, grinding, and sieving to obtain the required particle sizes [66][67][68]. The results show that adding seashell materials will reduce the strength of concrete, and when the replacement rate of concrete is below 20%, the concrete strength attenuation will be relatively weak [69][70][71][72]. ...
The use of seashells to replace traditional cement-based materials and study their adsorption capacity for pollutants can expand the functional engineering application range of cement-based materials. A large amount of seashell waste is produced in coastal areas every year. How to deal with and utilize this seashell waste is a common problem faced by coastal countries and regions. This paper first reviews the principles of adsorption kinetics and adsorption isotherms to demonstrate the adsorption mechanism of shell materials. Then the effects of pH, contact time, temperature, pollutant concentration and other factors on the adsorption of heavy metal ions and basic dyes to seashells are discussed. Finally, the relevant applications of seashells in the construction field are reviewed. The results showed that the optimal pH value in the process of seashell adsorption was 5–7, the active site on the surface of the seashell particles was limited, and that it would reach saturation at a certain concentration, but would not further increase with the increase of time. The active site area of the seashell would increase with the decrease of particle size, so the selection of seashell powder with small particle size was conducive to enhancing the absorption capacity and removal efficiency. The experimental use of seashells instead of cementitious materials or natural aggregates in cement-based materials showed good adsorption capacity and would have a wide range of application prospects in permeable concrete and architectural coatings. By analyzing the research progress on factors influencing seashell adsorption performance and the applications of seashell adsorption behaviors in cement-based materials, this paper could provide ideas and methods for the design of functional cement-based adsorption materials from multiple angles.
... Seashells can be considered as Ca-based by-product adsorbents. Clam shells, composed of approximately 96-99% CaCO 3 , can potentially be good adsorbents for the removal of fluoride from aqueous solutions because calcium is reactive toward fluoride (Lee et al., 2021a;Shafiu Kamba et al., 2013;Yusof et al., 2011). In the present study, Mactra veneriformis shells (MVS) were evaluated as fluoride removal adsorbents. ...
In this study, Mactra veneriformis shells (MVS), a seafood by-product with high Ca content, was assessed as an adsorbent for fluoride removal from contaminated water. MVS was calcined at various temperatures (100–900 °C), and MVS calcined at 800 and 900 °C (MVS-800 and MVS-900) had the highest adsorption capacity. The high fluoride adsorption of MVS-800 and MVS-900 originated from the conversion of CaCO3 present in the raw MVS to CaO and Ca(OH)2 by calcination at high temperatures. The kinetic and equilibrium adsorption of fluoride by MVS-800 were accurately described by the pseudo-second-order and Langmuir models, respectively. The maximum fluoride adsorption capacity was 244.61 mg/g, which is comparable to that of other adsorbents reported in the literature. The enthalpy and entropy of adsorption were 7.42 kJ/mol and 56.48 J/mol‧K, respectively, and the Gibbs free energy was negative at all reaction temperatures. The interactive effects of pH, reaction time, dosage, and temperature and the optimal values for fluoride removal by MVS-800 were explored using response surface methodology (RSM) and artificial neural networks (ANN). The RSM results demonstrated that reaction time, dosage, and temperature significantly influenced fluoride removal; however, pH was a significant term. The accuracy of the ANN model (R² = 0.9932) for predicting fluoride removal was higher than that of RSM (R² = 0.9347). The optimal fluoride removal at a dosage of 3.3 g/L under optimized conditions (pH 5; reaction time 9 h; temperature 35 °C) was predicted to be 98.5% by the ANN model.
... The shells were previously used in construction projects with aggregates [13]. To the best of my knowledge, replacing cement with shells such as clams, snails, and oysters in concrete production reduces cement use [13,14]. In the world, alternative materials such as GGBS, red mud, and silica fume have been used to replace cement [5]. ...
Snail shells are the bio-shells that eateries discard. Around 100 million tonnes of snail shells are come out as waste material in the world every year. These were creating substantial environmental problems and harm to living organisms. As mentioned earlier, the present work focuses on using snail shell powder (SSP) as a raw material in mortar. The current work compared the calcined and un-calcined snail shells powder behaviour in mortar concerning mechanical and durability properties. Calcined and un-calcined snail shell mortar composite is partially replaced Cement with snail shell powder of 0–35% with a variance of 5% in mortar. The chemical composition of both the mixes was assessed by X-ray diffraction (XRD) analysis. In addition, a compressive strength, flexure and split, and tensile strength test were performed on both mixes to determine the mechanical properties of mortar. Water absorption, sorptivity, and rapid chloride permeability tests on cement mortar were done on both mixes. According to the investigation results, the best use of snail shell powder is 30% for un-calcined shells and 25% for calcined shells. The durability properties of both mixes improved when the amount of snail shell powder increased, and neither blend showed much variation. Microstructural analysis viz., XRD, SEM, and EDS has been performed on both mixes and obtained higher C–H gel and C–S–H gel formations at 25% and 30% replacement of Cement of calcined and un-calcined snail shell powder.
... Integration of finer sized crushed cockle shell of 600um resulted in concrete with higher strength value than the mix consist coarse sized cockle shell of 2.36mm. Usage of finer seashells as fine aggregate can improve compressive strength due to the filling action of the fine particles in concrete [32]. ...
The widespread use of natural sand mined from the river for concrete production worldwide causes environmental degradation. The cockle shell waste from aquaculture industry which discarded at dumpsite also pollutes the environment. Utilization of cockle shell as partial sand replacement in concrete would reduce the harvesting of sand from the river and limit the waste dumping from cockle industry. The experimental research investigates the effect of different sizes crushed cockle shell (600µm and 2.36mm) as partial sand replacement on the workability and compressive strength of lightweight aggregate concrete. 5 types of concrete mixes consisting various percentages of crushed cockle shell ranging from 0%, 5%, 10%, 15% and 20% were used in this research. All specimens were water cured until the scheduled testing time. The workability and compressive strength of concrete were determined via slump test and compressive strength test respectively. The outcome shows that the use of different sized crushed cockle shell as partial sand replacement influences the workability and strength of concrete. The concrete becomes more workable when larger quantity of crushed cockle shell is used. Integration 5% of 600µm and 10% of 2.36mm crushed cockle shell forms concrete with the targeted strength. Using crushed cockle shell as mixing ingredient in concrete reduces quantity of waste thrown and contributes to cleaner surrounding.
... To the best of my knowledge, using the shells like clams, snails, oysters in the partial or full replacement of cement in concrete production, which reduces the cement usage in concrete constructions. [10,11]. Some other materials such as GGBS, red mud, silica fume were also utilized to replace cement in the world [5]. ...
Snail shells are the discarded bio-shell waste from restaurants, and oceans creating huge environmental problems for society. Living organisms are harmed when these shells are released. As previously stated, the work focuses primarily on the utilisation of snail shell powder as a raw ingredient in cement mortar. The mechanical and durability features of snail shell-based cement mortar were compared to the nominal mortar in this study. Snail shell powder, ranging from 0% to 35%, was used to partially substitute cement in mortar, with a variation of 5%. XRD (X-Ray Diffraction) was used to determine the chemical composition of both mixes. The mechanical properties of mortar for both mixes were determined using a compressive strength test. The tests on cement mortar viz., Water Absorption, Sorptivity, Acid Durability, and Rapid Chloride Permeability Test (RCP Test) were compared with nominal mortar mix. According to the results of the investigation, the optimum use of snail shell powder is 30%. The durability of both mixes increased by the increase of the snail shell powder. To detect the C-S-H gel formations, microstructural analysis was performed for both mixes.
... Generally, crushed seashells with sieved sizes below 5 millimetre used as fine aggregate. Yusof et al.(Yusof, James Ujai, Sahari, Taib, & Noor Mohamed, 2011) used crushed clam seashells as an alternative of partial fine ...
The concept of utilizing various types of wastes, such as agricultural dumps and marine by-products, as a partial replacement of cement, has gained a great interest to develop eco-friendly and economical mortars for sustainable construction. This study purports to evaluate the feasibility of using palm oil fuel ash (POFA), an agro-industrial waste by-product from palm oil mills and seashell powder (SSP) derived from seashells, a marine waste material as partial replacement of cement in mortars. The water to binder (w/b) ratio of 0.49 and the sand to binder (s/b) ratio of 2.54 with 0% to 30% of ordinary portland cement (OPC) by weight was replaced with POFA and SSP and the resulting mortar samples were tested for mechanical properties and durability. The compressive strength, flexural strength, water absorption, and flow table test were performed for different percentages of POFA and SSP after 7, 28, and 130 days. The results showed that the 30% POFA incorporated mortars achieved the highest compressive strength (35.12N/mm^2), flexural strength (4.06N/mm^2), high density with less water absorption (4.79%) after 130 days of curing and the high strength mortar with less water flow (22.2cm) during casting. Besides, it was also found that the 25% POFA and 5% SSP incorporated mortars attained acceptable results to be used as supplementary cementing material. This study suggests that the POFA and SSP incorporated mortars could be used in concrete for sustainable development of construction through efficient valorization of waste materials.
... Nonetheless, few studies claim different options for dehydrating and disinfecting shells. For instance, sea shells were oven-dried at 50°C for 24 h [64] 105°C for 4 h [54] 110°C for 24 h [25,56,58,60] or 135°C for 30 min [65]. Several techniques have been used to crush shells, including mechanical and manual crushing. ...
The increasing use of concrete in the ongoing construction industry worldwide demands for growing extraction of raw materials such as limestone, sand and stone from the earth which further destroy the natural environment. Realization on the destructive impact of this activity on flora and fauna as well as mankind, approach of utilizing by-product from any industry as partial substitution of mixing ingredient of concrete would reduce the consumption of natural resources and promote cleaner environment. In relation to that, oyster shell from fisheries industries which disposed as waste that pollutes the environment is seen as potential material to be incorporated in concrete. Thus, the utilization of oyster shell waste as cement and sand replacement in concrete research is reviewed in this paper. The paper presents the oyster shell’s properties, processing method prior to its use and the mechanical performance concrete upon the integration of oyster shell as cement and partial fine aggregate replacement respectively. On overall, utilization of oyster shell at suitable proportion able to enhance concrete strength. Further researcher needs to be conducted to explore the potential use of this material in high volume for high performance concrete production.
... However, at later ages beyond 56 days, the compressive strength of the mortar with oyster shell aggregate was lower compared to the control mortar, which was attributed to the build-up of stress concentration over time on the weaker oyster shell aggregate [41]. Similarly, Yusof et al. [52], and Muthusamy et al. [53] found an improvement in the compressive strength when up to 30% fine particles of clam shell (<0.5 mm) and cockle shell (<1.18 mm) aggregate were incorporated as sand replacement in concrete and cement-sand bricks, respectively. ...
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 certain regions, and is usually dumped or landfilled without any re-use value. This paper summarizes previous research concerning the use of seashell waste as a partial replacement for conventional materials in concrete and other related cement-based products. The characteristics of different types of seashell waste, as well as the effects of incorporating the seashells on the fresh and hardened properties of concrete, are discussed. The material characteristics suggest that, similar to limestone, seashell waste could be an inert material due to the high calcium oxide content. However, proper treatment such as heating at high temperature and crushing to achieve appropriate fineness are desirable for a better quality material. It is shown in past research that while seashell waste has been used as a replacement for both cement and aggregate, there is still a lack of investigation concerning its durability, as well as the actual influence of seashell powder as a cement replacement material. Despite the reduction in the workability and strength, based on the review, it is suggested that seashell waste could still be utilized as a partial aggregate at a replacement level of up to 20% for adequate workability and strength of concrete for non-structural purposes.
Snail shells are the discarded bio-shell waste from restaurants, and oceans creating huge environmental problems for society. Living organisms are harmed when these shells are released. As previously stated, the work focuses primarily on the utilisation of snail shell powder as a raw ingredient in cement mortar. The mechanical and durability features of snail shell-based cement mortar were compared to the nominal mortar in this study. Snail shell powder, ranging from 0% to 35%, was used to partially substitute cement in mortar, with a variation of 5%. XRD (X-Ray Diffraction) was used to determine the chemical composition of both mixes. The mechanical properties of mortar for both mixes were determined using a compressive strength test. The tests on cement mortar viz., Water Absorption, Sorptivity, Acid Durability, and Rapid Chloride Permeability Test (RCP Test) were compared with nominal mortar mix. According to the results of the investigation, the optimum use of snail shell powder is 30%. The durability of both mixes increased by the increase of the snail shell powder. To detect the C-S-H gel formations, microstructural analysis was performed for both mixes.
Shellfish farming is considered a highly sustainable form of aquaculture that has developed rapidly worldwide. Unfortunately, today biological and chemical pollution of the oceans and marine waters is widespread and has multiple negative impacts on marine ecosystems, which are exacerbated by global climate changes. In addition, such impacts on fisheries and aquaculture are significant in inducing socio-economic losses. Therefore, it is necessary to develop innovative solutions to improve productivity and environmental performance in line with the blue sustainable economy (European Green Deal).
However, one upcoming problem associated with shellfish consumption is shell waste and its disposal. In addition, the percentage of wasted shells destined for reuse is much lower than the one accumulated in landfills or in more or less well-managed sites. This represents a weakness of the shellfish farming sector that can only be mitigated through a project of shellfish waste recycling moving towards the circular economy, with undoubted environmental and economic advantages.
In the present study, we present a possible solution for recycling clam shells coming from the waste of the fishing industry (circular economy). Indeed, three eco-friendly bio-reefs for the stabilization and implementation of marine biodiversity (blue economy) were realized using additive manufacturing technology (3D printing) for large dimensions (technological innovation). Furthermore, before deploying the reefs on the sea bottom, they were colonized with oysters to promote repopulation.
The main aim of this study is to investigate the performance of calcined cockle shell as partial binder replacement in modified concrete (MC). Cockle shells was selected based on its high calcium carbonate (CaCO3) content; an active ingredient in cement manufacturing. The investigation was carried out by substituting the cement in the conventional concrete formulation with percentages of calcined cockle shells powder (10%, 20%, 30% and 40% respectively). Primary concrete parameters such as pH, carbonation depth, compressive strength and sorptivity were studied for the periods of 56 days. The results showed that modified concretes were performing better than control specimens and the performances were strongly influenced by the amount of substitutions. The addition of calcium carbonate in the mixture proved to increase the physical performance especially carbonation depth. However, the modified concretes’ strength developments are inversely proportional to the amount of substitutions. It is believe that the aragonite polymorphs contribute to the low strength development due to its different symmetry and crystal shapes to calcite thus leading to poor bonding properties of the matrix with aggregates. No significant strength developments were observed after 28 days for all modifications.
The concepts of eco-friendly building are getting more attention today. The use of materials from natural sources is an alternative to the realization of the green building concept. Considering this approach, a study was conducted to investigate the potential of cockle shell ash as a material for partial cement replacement or a filler material. The study was to determine the chemical composition of cockle shell ash and were determined using Fluorescence X-ray analysis. The observation of on the morphology structure based on SEM analysis was also performed. The next phase involved in determining the concrete properties such as compressive strength, tensile, modulus of elasticity, water permeability and porosity made from mixture of cockle shell ash of 5%, 10%, 15%, 25%, 50% and compared to normal concrete cured in ordinary water at the 7, 28, 90 days and up to 120 days for water permeability test. As a result, with the inclusion of 5% and 10% of cockle shell ash, morphology structure seems compacted that effected the strength, modulus of elasticity, permeability and porosity of the concrete.
In order to investigate the mechanical properties of particulate reinforced polyethylene when using rotational moulding process, different mathematical models are used to predict the tensile properties. A series of micro-sized particles at various volume fractions are used as fillers for Liner Medium Density Polyethylene (LMDPE) to verify those theoretical models. A comparison with the experimental results finds that the theoretical models of Halpin–Tsai–Nielsen and Nicolais–Narkis can be used to predict the tensile moduli and the tensile strengths, respectively, for the particulate reinforced composites produced by the rotational moulding process when uniform distribution of reinforcement is achieved. The scanning electron microscopic images show that an even distribution of particles within the product wall can be achieved in two ways: direct manual mixing method for bigger sized particles (90–240 μm) and melt compounding method for smaller particles (6.5–35 μm). It is also found that with around 2 vol% of the smallest Spheriglass 5000 beads added by the melt compounding method, the tensile strength remains almost the same and the tensile modulus reaches a 20% improvement above that of pure LMDPE.
The cement paste in the interfacial transition zone (ITZ) around aggregate particles has a significantly higher porosity than bulk cement paste. This elevated porosity will effect the transport properties of concrete. The penetration of Wood's metal into concrete samples indicates that the porosity in the interfacial zone is permeated preferentially to the bulk paste. This technique also indicates the width of the interfacial zone in which the porosity is interconnected.
The study was conducted to determine the composition of mineral content of cockle (Anadara granosa) shells from 3 major cockle cultivation of West Coast of Malaysia. Three samples of cockle shells from three different sources were evaluated to determine the content of 12 macro-and micro-elements (Calcium (Ca), Carbon (C), Magnesium (Mg), Sodium (Na), Phosphorus (P), Potassium (K), Ferum (Fe), Copper (Cu), Nickel ( Ni), Zink (Zn), Boron and Silica (Si)). For convenience and ease of reference, Ca and C were combine into one unit (Calcium Carbonate, CaC) while Mg, Na, P and K was evaluated individually and Fe, Cu, Ni, Zn, B and Si were evaluated as one group (others). Analysis of elements content was done using inductively Coupled plasma, Auto Analyzer, an Atomic Absorption Spectrophotometer and Carbon Analyzer. Results in this study revealed that the mineral compositions of cockle shells from 3 different sources in West Coast of Peninsular Malaysia were consistence almost in all the samples. The percentage of CaC comprises of more than 98.7% of the total minerals content of the cockle shells of the 3 sources. About 1.3 % of the composition are comprises of Mg, Na, P, K and others (Fe, Cu, Ni, B, Zn and Si).Overall, the minerals composition of cockle shells of West Coast of Peninsular Malaysia are as followed: CaC 98.7 %, Mg 0.05%, Na 0.9%, p 0.02 and others 0.2%.
The report on recycling and use of waste materials and by-products in highway construction will be of interest to administrators and policy makers; pavements, materials, geotechnical, and environmental engineers; and other professionals involved with highway design, construction, and maintenance. Information is provided on the technical, economic, and environmental aspects (including legislative and regulatory considerations) of recycling and on the specific applications of waste materials and by-products. Information is also provided on the quantities, characteristics, possible uses, current and past research activities, and actual highway construction use of each waste material or by-product. This information is classified into four broad categories based on source: agricultural, domestic, industrial, and mineral wastes.
A newly developed wet packing method has been applied to measure the packing densities of blended fine aggregates (each a mixture of fine aggregates of different sizes) and mortars (each a mixture of cement and blended fine aggregate) under the wet condition, with or without superplasticizer added, and with or without compaction applied. For the blended fine aggregates, the conventional dry packing method has also been employed to measure their packing densities under the dry condition and the results show that the packing density of fine aggregate is generally higher under wet condition than under dry condition. For both the blended fine aggregates and mortars, the measured packing densities have been compared to the predicted packing densities by two existing packing models. Good agreement between the measured and predicted packing densities has been achieved with the mean absolute error being 2.1% for the blended aggregates and 1.1% for the mortars. This is the first time that the packing densities of mortar samples are directly measured and compared to predictions by packing models to verify the applicability of the wet packing method and the packing models.
The aim of this study was to investigate the possibility of developing high performance concrete (HPC) using silica fume (SF) at relatively high water–binder ratios. For this purpose, water–binder ratios of 0.45 and 0.50 were considered. Test specimens were air and water cured and exposed to a medium temperature range of 20°C to 50°C. The compressive strength, modulus of elasticity and initial surface absorption (ISA) of hardened concrete were determined in the laboratory. Test results indicated that concrete under water curing offers the best results. The highest level of compressive strength and modulus of elasticity and the lowest level of ISA were produced by SF concrete under water curing and at temperature of 35°C. Data collected also revealed that, under controlled curing conditions, it is possible to produce HPC at relatively high water–binder ratios.
Influence of quarry dust and mineral admixtures on the 28 th day initial surface absorption of concrete
- S N Raman
- M F M Zain
- H B Mahmud
S.N. Raman, M.F.M. Zain, and H.B. Mahmud (2004). Influence of
quarry dust and mineral admixtures on the 28 th day initial surface
absorption of concrete. Sustainable Development in Concrete
Technology: Proceedings of the Seventh International Conference on
Concrete Technology in Developing Countries, Kuala Lumpur,
Malaysia: 32-42
Adhesion and aggrehation of fine particles, Powder technology
- K Kendal
- C Stainton
K. Kendal and C. Stainton (2001) Adhesion and aggrehation of fine
particles, Powder technology, 121:223-229