Mazidah Mukri

Effect of Nanoclay in Soft Soil Stabilization

The effectiveness of using nanoclay in soft soil stabilization was investigated by mean of laboratory testing to evaluate the compressive strength, effective shear strength and Atterberg limit test parameters. The soft soil sample, classified as slightly sandy CLAY of intermediate plasticity was used in this studies. The nanoclay was produced from pulverizing soft soil sample into nano sized using ball milling process. From the scanning electron microscopic (SEM) test and nano size analysis, it was found that the nanoclay particles were obtained from the milling process. However, only 3 % nanoclay was used in this study due to the limited samples produced from milling process. The first objective of this study was to determine the compressive strength of 3 % nanoclay mixed with soft soil and the second objective was to determine the effective shear strength of 3 % nanoclay mixed with soft soil. Meanwhile, the third objective of this study was to determine the Atterberg limit parameter: liquid limit (LL), plastic limit (PL) and plastic index (PI) of 3 % nanoclay mixed with soft soil. This study involved three main testing such as unconfined compression strength to determine the compressive strength and consolidated drained test to determine the effective shear strength. Meanwhile, the Atterberg limit test were conduct to determine the liquid limit (LL) and plastic limit (PL). The result showed that the mixing of 3 % nanoclay with soft soil was improved the soil strength and effectiveness of the shear strength.

GEOPHYSICAL MEASUREMENT FOR ESTIMATION OF GROUNDWATER HYDRAULIC PROPERTIES

In the study, a relationship was establishment between electrical resistivity by using electrical resistivity imaging (ERI) technique with hydraulic conductivity. By using Schlumberger array configuration, 2D electrical resistivity image was produced by using ABEM SAS 4000 with eighty-one (81) electrodes (Loke, 2004) [1]. By using regression equation, hydraulic conductivity was calculated from electrical resistivity and this result was compared with the hydraulic conductivity obtained from pumping tests (Butler, 2005). This data suggested that electrical resistivity survey can be used as preliminary tool to assess any subsurface zone with non- invasive nondestructive for soil, reducing time and cost.

Study of nano-kaolinite properties in clay liner application

This paper reports the outcome of the laboratory investigation conducted on new clay liners modified with kaolinite combined with various content of lime-treated, various content of bentonite and admixture of kaolinite adding with 3% nano-kaolinite for composition. The 3% nano-kaolinite was chosen based on earlier finding by S.V.Netethu (2013). The various content of lime-treated and bentonite adopted are 2.0%, 5.0%, 7.5% and 10.0% by total weight of the kaolinite. Compaction tests was performed on the resulted modified clay liner samples to evaluate the best percentage that gives optimum moisture content (OMC) and maximum dry density (MDD) . The best percentage of each bentonite and lime-treated are chosen and be added into kaolinite and the physical properties of samples are tested and compared to the other two samples which are kaolinite only and kaolinite added with 3 % of nano-kaolinite. Nano-kaolinite was produced using a mill machine and the sized of nano-kaolinite (1nm-100nm) were examined under Scanning Electron Microscope (SEM) machine.The addition of 3% nano-kaolinite to the kaolinite gives the best compaction result compared to bentonite or lime-treated. The value of dry density is increased to give the reduction of air voids, thereby reducing the hydraulic conductivity by concept. Based on the compaction test value, it clearly observed that admixture of kaolinite adding with 3% nano-kaolinite gives the best results from the other samples due to required less water to achieve maximum dry density of 1.39 Mg/m3 and 27.34% of optimum moisture content resulted positive effect in soil properties.

Effect on physical properties of laterite soil with difference percentage of sodium bentonite

This research was carried out in an attempt to know the physical properties of laterite soil with the appearance of difference percentage of sodium bentonite. Lateritic soils usually develop in tropical and other regions with similar hot and humid climate, where heavy rainfall, warm temperature and well drainage lead to the formation of thick horizons of reddish lateritic soil profiles rich in iron and aluminium. When sodium predominates, a large amount of water can be absorbed in the interlayer, resulting in the remarkable swelling properties observed with hydrating sodium bentonite. There are some basic physical properties test conducted in this research which are Specific Gravity Test, pH Test, Sieve Analysis, Hydrometer Test, Shrinkage Limit and Atterberg Limit. The test will be conducted with 0%, 5%, 10%, 15% and 20% of sodium bentonite. Each test will be repeated three times for the accuracy of the result. From the physical properties test the soil properties characteristic react with the sodium ben...

Prediction of settlement by using finite element simulation 2D program at Seksyen 7, Shah Alam

Construction on soft ground often involves a number of geotechnical issues especially that related to settlements. Excessive post-construction settlements may they be total or differential have always caused serious problem to all parties in the project. Insufficient knowledge on existing ground conditions due to lacking of a proper site investigation coupled with inadequacy in design especially in the foundation for supporting structure could be the likely reasons for causing this problem and lead to eventual instability of the structure above. In general, a reasonably accurate assessment on the rate of settlement of soil is a very important factor in ensuring the achievement of structurally sound building and/or infrastructural work on soft ground without the development of excessive post–construction settlement. In the current investigation, sensitivity analysis to enhance prediction of settlement is carried out using the PLAXIS Finite Element 2D Program by setting the relevant control parameters. This...

The Influence of Compaction Effort in Laterite Soil with the Appearance of Sodium Bentonite as a Soil Liner

Soil liner which is placed at the foundation of a landfill is very important in order to isolate waste materials and leachate from the environment. However, if not properly managed, the leachate can beriskytothe safety and serviceability of which are directly related to the environment and public health issues. Soil liners were proposed to minimize leachate egress and prevent ground pollution. In soil liner design, it is important to compact the layer properly in order to achieve low hydraulic conductivity and high strength of soil. In this study, different percentages of sodium bentonite were added to laterite soil to act as soil liner to stabilize the liner system. Sodium bentonite can easily absorb water more than a hundred percent of its weight. Thus, the sodium bentonites were chosen to be mixed with laterite soil. The differentpercentagesof sodium bentonite used are 5%, 10%, 15% and 20%. This research was carried out asan attempt to see the compaction effort for laterite soil mixedwith sodium bentonite. The outcomesof this study give positive results due to the potential of sodium bentonite to fulfill spaces in between soil particles. It is also found that sodium bentonite influences the resistance properties, hydraulic conductivity and the strength of soil.

Flood Disaster Management in Malaysia: Standard Operating Procedures (SOPs) Review

Flood is a natural weather-related disaster frequently occurring in Malaysia. One of the greatest challenges that Malaysia faces today is recognizing the magnitude of risks posed by flooding. The public, private and NGOs should deliberate the amount of investments required to reduce the flood risk, including making appropriate emergency preparations, strengthening the existing Standard Operating Procedures (SOPs), and finding new solution for minimizing risk related to flood disaster. The current existing SOPs indicate that there is still lack of holistic flood risk management system to minimize this problem. The country should be committed to establish a national policy on flood risk management that requires effective, economical, sustainable, and consistent management of flood risk to people, properties, and communities. Risk management has been established as a well-defined procedure for handling risks due to natural, environmental, and man-made hazards. A risk management can be applied at every level of the action: planning, design, and operation level. A holistic flood risk management system will evaluate the potential risk before, during, and after the flood disaster. The paper reviews the current SOPs implemented by the agencies dealing with flood disaster in Malaysia.

Compaction characteristics of banting soft soil subgrade stabilized using waste paper sludge ash (WPSA)

This paper presents the laboratory result on compaction characteristic for soft soil subgrade which was stabilized by using waste paper sludge ash (WPSA). The soft soil sample was collected from Banting Selangor, Malaysia named as Banting soft soil and classified as slightly sandy Clay with intermediate plasticity. Additive of WPSA is a finely waste product produced from the incinerated waste paper. In ASTM C618, this WPSA samples are categorized as Type-C fly ash due to the high free lime (CaO) content (>20%) and possesses some cementitious and pozzolanic, resulting in the self-cementing characteristics. Therefore no entire activators such as lime are required. Objectives of this study are to determine the dry density and moisture content of Banting soft soil stabilized by WPSA through the different energy and method of compaction and to determine the Atterberg limit properties of Banting soft soil stabilized using WPSA. Several percentage of WPSA (4%, 8%, 12% and 16%) was used to stabilize the soft soil...

SOFT Soil Subgrade Stabilization Using Waste Paper Sludge Ash (WPSA) Mixtures

This paper presents findings on the soft soil stabilization using waste paper sludge ash (WPSA). A laboratories testing was conducted to determine the compressive strength, total shear strength and effective shear strength on soft soil subgrade stabilized using WPSA mixtures. Instead, the microstructure of soft soil and stabilized soft soil was investigated to evaluate the role of WPSA to the strength of stabilized soft soil. The soft soil subgrade sample, categorized as slightly sandy CLAY of intermediate plasticity used in this study was stabilized using Class-C of WPSA. The first objective is to determine the maximum compressive strength and optimum percentages of WPSA mixtures. The second objective is to determine the total shear strength and effective shear strength of soft soil stabilized with optimum percentage of WPSA. The third objective is to investigate the effect of WPSA to the strength of stabilized soft soil by microstructure testing by scanning electron microscopic test (SEM). This study involved three main testing. First testing was unconfined compression test to determine the compressive strength. Second testing was consolidated undrained test to determine the total shear strength and third testing was consolidated drained test to determine the effective shear strength. Third testing was microstructure testing by scanning electron microscopic test (SEM). The result shows, the addition of 10 % WPSA were giving the highest compressive strength about 737 kPa and improved the total strength and effective strength to stabilize the soft soil due to the crystal formation from the pozzolanic reaction.

The Study of Interface Shear Strength Between Geotextile and Soil Liner Containing Different Percentage of Sodium Bentonite

The purpose of this research is to focus on the interface shear strength between geotextiles and soil with different percentage of sodium bentonite. Firstly, the physical properties of the soil samples must be identified in order to determine the soil classification. The laboratory tests include atterberg limit test, shrinkage limit test, specific gravity test, pH test, sieve analysis test and hydrometer test. The soil samples are natural soil sample, soil added with 0 % of sodium bentonite, soil added with 2.5 % of sodium bentonite, soil added with 5.0 % of sodium bentonite, soil added with 7.5 % of sodium bentonite and soil added with 10 % of sodium bentonite. Based on the test results, the added percentages of sodium bentonite did not appear to have any effect on the properties of the soil samples such as the liquid limit, plastic limit and specific gravity. This is because the values obtained were approximately the same and no apparent changes were detected. However, the shrinkage limit and pH test results shows an increasing trend with the increase of sodium bentonite percentage. The natural soil can be classified as Sandy SILT of Intermediate Plasticity (MI). After classifying the soil samples, compaction tests were performed to get the values of optimum moisture content required during direct shear box test. As with liquid limit plastic limit and specific gravity tests, the results for compaction and direct shear test also did not give good results, as the values of optimum moisture content, cohesion and friction angle were also quite similar to each other. Thus, it can be clearly said that, as an admixture, sodium bentonite did not affect the soil samples, therefore not suitable for this type of soil.