A parametric study of DMS subjected to induced low-stress consolidation and heat treatment

Dredging activities are important either in the control the accessibility and navigability to harbours or the maintenance to the existing facilities. Dredged marine sediments (DMS) is the products generated from dredging activities. DMS consists mainly of clays, silts and sand mingled with rocks, debris, larger obstacles and organic matter such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated aromatic biphenyl (PCBs

Development and field testing of Geocomposite Cellular Mats (GCM) to minimize the ground movements of highway embankments founded on peat ground

Challenging grounds are often met in planning, design and construction of highway embankments which as a consequence succumb to undesirably excessive ground movements. Such ground conditions can range from unforeseen cavernous grounds to soft compressible organic soils of variable depths. Often alternate route planning is not feasible, and if necessary alternative construction procedures are not adopted, the net result will be unwanted roads user discomforts such as bumpy roads or even fatal road collapse. Highway constructions norms to circumvent such occurrences are to replace with alternative transported foundation soil/ground improvement or use an appropriate form of geo mats. Hence, this paper presents an alternative and innovative lightweight fill material: Geocomposite Cellular Mat (GCM) used to minimize the ground movements of highway embankments over peat ground. The conceptual development of a stiff mat structure but with a weight lighter than the embankment fill soil is described. The material used for the stiff mat is environmentally friendly in utilizing recycled plastic and its structure, enabling the free movement of water to dissipate any excessive porewater pressures. The performance of theGCMwas appraised under field trial conditions on a test site in Parit Nipah, Johor, Malaysia. The site comprised of a vast expanse of hemic peat and environmental conditions at the test site were fully monitored. The geotechnical properties of the peat at Parit Nipah were typically high organic matter content (~85%), high moisture content (>600%) and very low undrained shear strength (<15 kPa). Details of the set up and layout of the trial embankments tested are fully described, and the techniques adopted to get a comprehensive narrative of the settlement characteristics using innovative measurement techniques are also described. The performance of the GCM incorporated embankment was compared with that of a similar embankment that was formed of conventional backfill (sand fill). The findings show that the field ground movement observations confirmed that themaximum settlementswere reduced by up to 84% with the GCMfills.Moreover, the differential settlements were reduced by up to 70%

The characterization of recycled concrete aggregate as filter in removal of phosphorus

Phosphorus (P) is one of the key nutrients that lead to eutrophication problem in surface water. However, the existing conventional wastewater treatment system to remove phosphorus is expensive and require a complex process. Therefore, a system using low cost and environmental friendly should be practiced to overcome this problem. Recycled concrete aggregate (RCA) used as a filter system emerged as an alternative technology for phosphorus removal. This can overcome the problem of construction site waste by converting the waste into something valuable products. Thus, this study aim to investigate the physical and chemical characteristic of RCA that influenced adsorption of P. RCA was analyzed using Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) testing to determine chemical composition. Results shows that RCA is highly contained with Aluminium, Calcium and Magnesium elements that enhanced the Phosphorus adsorption

An Overview of Waste Materials for Sustainable Road Construction

Untreated soil typically has low shear strength, swelling behavior, high compressibility and its characteristics were highly dependent on the environment. In general, such problematic soil will lead to severe damages in road construction industry such as bearing capacity failure, slope instability, and excessive settlement. Agricultural waste, construction waste, and municipal waste have recently gained considerable attention as a sustainable material in road construction application due to its availability, environmental friendly and low-cost materials. Therefore in this review, randomly distributed fiber reinforced soil and oriented distributed fiber reinforced soil will be extensively discussed based on the emerging trend. It further reviewed the feasibility of using waste materials as a reinforcement material for the road construction industry. The review also attempts to evaluate and compare the engineering properties of soil and sustainable materials in order to enhance soil performance as well as help to improve the environment affected by growing waste materials

Evaluation of soaked and unsoaked CBR values of reinforced-soil with coconut husk fibre (CHF)

Recently, soil reinforcement has received more attention due to sustainability, simplicity, and costeffectiveness. The research aimed was to evaluate the efficacy of coconut husk fibre (CHF) in improving the strength properties of laterite soils. A series of laboratory tests such as Atterberg limit test, specific gravity test and hydrometer test was carried out on raw soil. Physical tests were conducted on CHF including density, specific gravity test, and water absorption testing. Geotechnical properties of both unreinforced and reinforced soils were determined through the compaction test and soaked and unsoaked California bearing ratio (CBR) test. The reinforced-soil was prepared by mixing with different ratio of CHF of 0%, 0.25%, 0.50%, 0.75%, 1.00% and 1.50% by mass of dry soil. All unreinforced samples (control samples) are prepared with 0% of CHF. From this research, it had been identified that 0.75% of CHF has the highest CBR value of 27%

The efficacy of recycled concrete aggregate for removal phosphorus in synthetic wastewater with different pH value

Phosphorus (P) is the main nutrient element for plant growth in the natural water system. However, unnecessary phosphorus loads in water bodies from industrial, agricultural and household wastes may cause the overgrowth of aquatic plants or algae which accelerates the depletion of dissolved oxygen (DO) in water, thereby leading to serious eutrophication problems. Nevertheless, existing conventional wastewater treatment systems for removing phosphorus are expensive and complex. Recycled concrete aggregate (RCA) may be an alternative solution for phosphorus removal. It can reduce pollution and landfill disposal by converting construction waste into valuable products. This study aims to investigate the percentage of phosphorus removal using three different sizes of RCA with different pH of synthetic wastewater. A total of four vertical laboratory-scale RCA filters were designed with four different concentrations of synthetic wastewater which is pH3, pH7, pH9 and distilled water were prepared. The pH and the percentage of phosphorus removal (%) were tested and analysed on both untreated and treated sample. RCA was analysed using Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) to determine its chemical composition. The results show that RCA has a high content of aluminium, calcium and magnesium that enhances phosphorus adsorption. The pH values are substantially higher for RCA size 5 mm to 10 mm compared to RCA size 10 mm to 15 mm, and 15 mm to 20 mm. Moreover, it was shown that the higher the pH, which is at pH 9 and the smaller size of RCA, the higher the efficiency of phosphorus removal, which is 96% of removal. In conclusion, RCA has the potential to remove phosphorus, particularly in low concentrations of synthetic wastewater and high pH conditions

The Efficacy of Recycled Concrete Aggregate for Removal Phosphorus in Synthetic Wastewater with Different pH Value

Phosphorus (P) is the main nutrient element for plant growth in the natural water system. However, unnecessary phosphorus loads in water bodies from industrial, agricultural and household wastes may cause the overgrowth of aquatic plants or algae which accelerates the depletion of dissolved oxygen (DO) in water, thereby leading to serious eutrophication problems. Nevertheless, existing conventional wastewater treatment systems for removing phosphorus are expensive and complex. Recycled concrete aggregate (RCA) may be an alternative solution for phosphorus removal. It can reduce pollution and landfill disposal by converting construction waste into valuable products. This study aims to investigate the percentage of phosphorus removal using three different sizes of RCA with different pH of synthetic wastewater. A total of four vertical laboratory-scale RCA filters were designed with four different concentrations of synthetic wastewater which is pH3, pH7, pH9 and distilled water were prepared. The pH and the percentage of phosphorus removal (%) were tested and analysed on both untreated and treated sample. RCA was analysed using Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) to determine its chemical composition. The results show that RCA has a high content of aluminium, calcium and magnesium that enhances phosphorus adsorption. The pH values are substantially higher for RCA size 5 mm to 10 mm compared to RCA size 10 mm to 15 mm, and 15 mm to 20 mm. Moreover, it was shown that the higher the pH, which is at pH 9 and the smaller size of RCA, the higher the efficiency of phosphorus removal, which is 96% of removal. In conclusion, RCA has the potential to remove phosphorus, particularly in low concentrations of synthetic wastewater and high pH conditions

The performance of removal phosphorus

Turphorus is an important nutrient constituent for aquatic plant growth in the natural water system. However, excessive phosphorus loads in water bodies due to industrial, agricultural and household wastes might cause the overgrowth of aquatic plants or algae. This will accelerate the depletion of dissolved oxygen (DO) in water and lead to eutrophication. Hence, strict effluent quality standards for wastewater treatment plants (WWTPs) are implemented by governments all over the world [13]. Municipal wastewaters comprehend from 5 to 20 mg/L of total phosphorus, of which 1-5 mg/l are organic and the rest are inorganic. Phosphorus is one of the main constituents of synthetic detergents. The individual phosphorus impact varies between 0.65 and 4.80 g/inhabitant per day with an average of about 2.18 g. Generally, secondary treatment can only remove 1-2 mg/L of phosphorus, so excess phosphorus is often discharged in the final effluent and causes eutrophication in surface water [9]. [5] found that the addition of phosphorus in the range of even 0.1-5.6 µ/L over a long period might activate algal blooms in part of a natural lake. Therefore, phosphorus removal from wastewater is important. To remove phosphorus, it must either be rehabilitated into a particulate form or removed as a particulate by sedimentation or filtration using membrane treatment. The most regularly used method for phosphorus removal from wastewater is chemical precipitation and this method is able to reduce the concentration of phosphorus to values below 1 mg/L in sewage treatment plants. Nevertheless, chemical precipitation is expensive in many parts of the world and it might produce new pollutants such as chloride and sulphate [4]. In addition, it also requires the disposal for the precipitate formed and neutralisation of the treated effluent

Improvement of soft soil stiffness using geo-composite cellular mat

The highway construction over sub-grade consisting of problematic soils gives challenges to the engineer due to their weak geotechnical characteristic [1, 2, 3]; High water content, High compressibility, and Low bearing capacity

Decomposition of Food Waste by using Vegetable Fermentation Solution

Food waste is an inevitable outcome of human consumption in modern society, it was happened in almost every home on a daily basis. The increasing amount of food waste in Malaysia caused by the fast growth of population and to meet the human lifestyle has become a major environmental issues in recent years. SWCorp (2016) reported that it was contributes the highest composition in municipal solid waste which is 44.5%. In 2015, Malaysians throw away of about 15,000 tonnes of food waste every day, about 3,000 tonnes are actually eatable and should not be dumped (Jarjusey & Chamhuri, 2017). In 2020, about 49,670 tons per day of waste is expected to be generated in Malaysians (Jabatan Pengurusan Sisa Pepejal Negara, 2012)