Determination of Unconfined Compressive Strength and Atterberg Limit of Soft Clay by Stabilizing with Sodium Silicate and Biomass Silica in Batu Pahat

Soft clay soils can be considered as problematic soil with the characteristic of high compressibility, low permeability and low shear strength. Construction on soft clay deposit may causes problem such as insufficient bearing capacity, settlement problem and instability on excavation and embankment. Ground improvement methods were used as the aimed of this study is to determine the effect of non-traditional stabilizer on the compressive strength of soft clay soils. Therefore, the objective of this study is to determine effect of compressive strength of untreated and treated soft clay soil with addition of non-traditional stabilizer at different curing periods. The soil properties of soft clay soil such as compaction, Atterberg limits, and unconfined compression strength (UCS) testing methods were used to observe the performance of treated and untreated samples. The test results from the UCS indicated that once Biomass Silica and Sodium Silicate in the form of SH-85 and TX-85 have been added to the clay soil, the strength of the sample will increase with increasing percent of sodium silicate and curing periods

The optimization of heating temperature for carbon extraction from peat soil

This study aims to find the optimised heating temperature for carbon extraction from peat soil. Ccarbon from peat soil was extracted by the pyrolisation process at temperature, T = 200, 300, 400, 500, 600 and 700°C for 5 hours. The carbon, C and silica, Si content extracted from peat soil at various heating temperatures were measured by using an Energy Dispersive X-Ray analyzer (EDX) at 3 points on the sample surface. High atomic percentage of carbon (95.44 %) was measured at T = 400°C, while the highest atomic percentage of silicon was recorded at T = 700°C (30.79 %). The surface morphology of peat soil was analysed using Scanning Electron Microscope (SEM) at 800 magnifying power, and it was clearly seen that peat fragments were pyrolised at high heating temperature with pores enhancement. The molecular structure parameter of the extracted carbon were identified using Laser Raman analysis. The peak positions of D-band and G-band for raw peat soil were observed at Raman shift of 1379.62 and 1549.02 cm-1, respectively. Meanwhile, the D-band for peat soil heated at temperature of 400°C was 1391.56 cm-1 whereas the G-band has peak position at 1562.16 cm-1 . From the Raman spectra of the optimum heating temperature at 400°C, it was revealed that the carbon molecular structure from the peat soil is mainly attributed by graphite and diamond structure

The influences of basic physical properties of clayey silt and silty sand on its laboratory electrical resistivity value in loose and dense conditions

Non-destructive test which refers to electrical resistivity method is recently popular in engineering, environmental, archaeological and mining studies. Based on the previous studies, the results on electrical resistivity interpretation were often debated due to lack of clarification and evidences in quantitative perspective. Traditionally, most of the previous result interpretations were depending on qualitative point of view which is risky to produce unreliable outcomes. In order to minimise those problems, this study has performed a laboratory experiment on soil box electrical resistivity test which was supported by an additional basic physical properties of soil test like particle size distribution test (d), moisture content test (w), density test (ρbulk) and Atterberg limit test (LL, PL and PI). The test was performed to establish a series of electrical resistivity value (ERV) with different quantity of water content for clayey silt and silty sand in loose and dense condition. Apparently, the soil resistivity value was different under loose (L) and dense (C) conditions with moisture content and density variations (silty SAND = ERVLoose: 600 - 7300 Ωm & ERVDense: 490 - 7900 Ωm while Clayey SILT = ERVLoose: 13 - 7700 Ωm & ERVDense: 14 - 8400 Ωm) due to several factors. Moreover, correlation of moisture content (w) and density (ρbulk) due to the ERV was established as follows; Silty SAND: w(L) = 638.8ρ-0.418, w(D) = 1397.1ρ-0.574, ρBulk(L) = 2.6188e-6E-05ρ, ρBulk(D) = 4.099ρ-0.07 while Clayey SILT: w(L) = 109.98ρ-0.268, w(D) = 121.88ρ-0.363, ρBulk(L) = -0.111ln(ρ) + 1.7605, ρBulk(D) = 2.5991ρ-0.037 with determination coefficients, R2 that varied from 0.5643 – 0.8927. This study was successfully demonstrated that the consistency of ERV was greatly influenced by the variation of soil basic physical properties (d, w, ρBulk, LL, PL and PI). Finally, the reliability of the ERV result interpretation can be enhanced due to its ability to produce a meaningful outcome based on supported data from basic geotechnical properties

Electrical resistivity and induced polarization techniques for groundwater exploration

Abstract: Electrical resistivity and induced polarization surveys have been conducted for groundwater exploration at two different sites of geological aged i.e. Carboniferous and Quaternary. This study discussed the earth materials resistivity and chargeability for metasedimentary rock and unconsolidated sediment for groundwater exploration at Kampung Jongok Batu, Dungun and Kampung Paya Rawa, Besut, respectively. For this study Terrameter LS2, cable, electrode, cable connector, battery and remote cable are tools for measurement. The spacing between electrodes is 5 m, maximum length of spread line is 400 m and using Pole-Dipole protocol. Via comparing between the resistivity and chargeability values able to provide better interpretation for ground water exploration for metasedimentary rock and unconsolidated quaternary sediment. The result shows the important of chargeability for refining the resistivity value for locating the groundwater position.Â

Investigation of dielectric constant variations for Malaysians soil species towards its natural background dose

The correlation of natural background gamma radiation and real part of the complex relative permittivity (dielectric constant) for various species Malaysian soils was investigated in this research. The sampling sites were chosen randomly according to soils groups that consist of sedentary, alluvial and miscellaneous soil which covered the area of Batu Pahat, Kluang and Johor Bahru, Johor state of Malaysia. There are 11 types of Malaysian soil species that have been studied; namely Peat, Linau-Sedu, Selangor-Kangkong, Kranji, Telemong�Akob-Local Alluvium, Holyrood-Lunas, Batu Anam-Melaka- Tavy, Harimau Tampoi, Kulai�Yong Peng, Rengam-Jerangau, and Steepland soils. In-situ exposure rates of each soil species were measured by using portable gamma survey meter and ex-situ analysis of real part of relative permittivity was performed by using DAK (Dielectric Assessment Kit assist by network analyser). Results revealed that the highest and the lowest background dose rate were 94 ±26.28 μR hr-1 and 7 ±0.67 μR hr-1 contributed by Rengam Jerangau and Peat soil species respectively. Meanwhile, dielectric constant measurement, it was performed in the range of frequency between 100 MHz to 3 GHz. The measurements of each soils species dielectric constant are in the range of 1 to 3. At the lower frequencies in the range of 100 MHz to 600 MHz, it was observed that the dielectric constant for each soil species fluctuated and inconsistent. But it remained consistent in plateau form of signal at higher frequency at range above 600 MHz. From the comparison of dielectric properties of each soil at above 600 MHz of frequency, it was found that Rengam-Jerangau soil species give the highest reading and followed by Selangor-Kangkong species. The average dielectric measurement for both Selangor-Kangkong and Rengam-Jerangau soil species are 2.34 and 2.35 respectively. Meanwhile, peat soil species exhibits the lowest dielectric measurement of 1.83. It can be clearly seen that the pattern of dielectric measurement for every soil at the frequency above 600 MHz demonstrated a specific distribution which can be classified into two main regions which are higher and lower between the ranges of 1.83 to 2.35. Pearson correlation analysis between the frequency of 100 MHz and 2.6 GHz with respect to exposure rate for every soil species was r = 0.38 and r = 0.51, respectively. This indicates that there was no strong correlation between both parameter, natural background dose and soils dielectric for each soils sample. This factor could be contributed by major and minor elements contained in each soils sample species, especially Ferum, Fe and Silica, Si

The electrokinetic stabilization (EKS) impact on soft soil (peat) stability towards its physical, mechanical, and dynamic properties at Johor state, Peninsular Malaysia

Peat is considered one of the most problematic soils in the construction industry due to its poor physical, mechanical, and dynamic properties. It exists in the coastal part of peninsular Malaysia, and covers almost 8% of the country's land. Therefore, building or road foundations on peat in the coastal region are deemed a serious threat to construction engineers. Thus, it's essential to strengthening its weak properties. This study aims to improve the physical, mechanical, and dynamic peat properties, including shear strength, maximum dry density, moisture content, liquid limit, and shear wave velocity. The soil samples were collected from different locations in Parit Botak area, Batu Pahat District, Johor state, Peninsular Malaysia. The electrokinetic stabilization (EKS) method was applied with an operated electric gradient of 150 V through an aluminum electrode on anode and cathode for 6 hours. As a result, the change in moisture content, liquid limit, density, and shear wave velocity has indicated that post-treatment stability has been improved. It is, therefore, concluded that the EKS technique is effective and capable of strengthening the properties of soft soil

Utilization of sugarcane BagAsse ash for stabilization/solidification of lead-contaminated soils

Recently, many researchers are interested in using agricultural waste as an additive to remediate the contaminated soils. In this study, the effectiveness of sugarcane bagasse ash (SCBA) as the substitution binder to Ordinary Portlant Cement (OPC) content in Stabilization/Solidification (S/S) method was investigated through the physical and chemical characteristics namely the Unconfined Compressive Strength (UCS) and Toxicity Characteristic Leaching Procedure (TCLP). Synthetic contaminated soil was prepared in bulk by mixing soil samples with lead nitrate to achieve the concentration of 500 ppm. The OPC and SCBA varying from 5% to 20% were added to stabilize and solidify the contaminated soils. The cylindrical specimens (D = 38 mm, H = 76 mm), was compacted in five layers with 50 blows each. A further 3, 7, 14 and 28 days were allowed for curing in the temperature 25±2 ?C and humidity > 80%. Results indicate that all samples containing OPC and SCBA satisfy the US EPA strength requirement of 0.35 MPa for S/S sample. The TCLP testing shows that sample containing OPC with SCBA has been successful treated which produced the leachability below US EPA limit for lead of 5 mg/L. In conclusion, the use of SCBA as part of replacement of OPC has been successful in increasing the strength and reducing the leachability compared to untreated sample

Integral application of electrical resistivity tomography, geochemistry and borehole data in groundwater seepage assessment

Electrical resistivity tomography (ERT) has increasingly adopted as an alternative approach in engineering, environmental and archeological studies. In the past, several limitation of conventional method in groundwater mapping was always relative to the high cost, time consuming and limited data coverage. Hence, this study adopted an ERT in order to identify the unknown problematic zone due to the excessive groundwater seepage occurrences. During data acquisition, five (five) ERT spread lines was conducted using ABEM SAS4000 equipment set. Then, field raw data was processed using RES2DINV and ROCKWORKS software to generate 2-D and 3- D of the inverse model resistivity section respectively. Engineering properties and information related to the borehole and geochemistry results was also used for interpretation and verification purposes. Geochemistry test was performed to identify groundwater sources using Atomic Absorption Spectrometer (AAS) and Ion Chromatography (IC) in order to determine the elements of cation (sodium, potassium, calcium and magnesium) and anions (chloride, bicarbonate, nitrate and sulfate) respectively. Based on ERT results, it was found that low electrical resistivity value (10 ~ 100 Ωm) which commonly associated to groundwater was detected at ground surface (0 m) until greater depth (> 10 m). Furthermore, it was found that the groundwater was classified as Ca-HCO that indicates the water was originally come from a typical shallow of the fresh groundwater. Finally, this study has successfully demonstrate that the integral application of ERT, geochemistry and borehole data was applicable to produced comprehensive outcome with particular reference to the problematic groundwater seepage assessment

Electrokinetic stabilisation of soft clay

The application of chemical ground improvement using the electrokinetic stabilisation(EKS)method has the potential to overcome problems soft highly compressibility soil. This technique has the potential to enhance the strength and reduce compressibility of a wide range of soils. The aim of this study was to evaluate the use of EKS as an effective method to strengthen soft clay soils. A detailed laboratory programme of work was conducted using the initial base model developed by Liaki (2006). This study was conducted in two stages using laboratory scale models, using an inactive kaolinite clay. The test model using reusable Electrokinetic Geosythentics (EKG) developed at the Newcastle University to apply a constant voltage gradient of 50 V/m across a soil sample approximately 400 mm. The first stage involved testing of a ‘pure’ system with distilled water as the main pore electrolyte fluid supplied under zero hydraulic gradient conditions for periods of 3, 7 and 14 days. The second stage repeated test using calcium chloride and distilled water (CaCl-DW), DW and sodium silicate (DW-NaSiO) and CaCl-NaSiO, at the anode and cathode, respectively. Throughout both physical and chemical characteristics were measured. This enabled assessment of the design and configuration that could be used in the field together with a number of key limitations. The data presented herein enables a fuller understanding of the mechanisms contributing to the improvements achieved and how effective monitoring through the use of relatively simple test, e.g. pH and Atterberg Limits, can be achieved. Specifically cation exchange was considered to be the main mechanism causing a significant increase in shear strength observed for the CaCl-DW system with the increase seen to be more uniform across the soil sample for a period up to 14 days. This was supported by results of Atterberg limits

Ciri-ciri kejuruteraan, mineralogi dan mikrostruktur tanah liat lembut di Semenanjung Malaysia

Soft clay deposits are available along the west coast and some parts of the east coast of Peninsular Malaysia. Due to the increase in population and good economic growth, a lot of projects are implemented in these areas. Constructions on soft clays are often affected by stability and settlement problems. Therefore, in order to counter these problems, one has to know the engineering properties, mineralogy and the microstructure of the soft clay. Samples of soft clay for this study are taken at certain depth from construction sites being carried out along Peninsular Malaysia. This study is carried out to identify the engineering properties of soft clay such as soil index, consolidation characteristics, shear strength parameters, mineralogy and microstructure of the soil. Correlations and brief catalogues are produced to assist in the preliminary design process. X-rays diffraction (XRD) and X-rays fluorescence (XRF) are used to determine the mineralogy of soft clay. Scanning electron microscopy (SEM) is used to study the microstructure of clay. From this study, it can be concluded that the soft clays in the research area have high moisture content which reaches 139%. Whereas, the specific gravity (G,) is between 2.42 - 2.65, compressibility index (C,) is between 0.09 - 1.36, coefficient of consolidation (c,) is between 1.24 - 8.72 m21years and coefficient of volume compressibility (m,) is between 0.056 - 2.084 mZ/MN. The effective cohesion (c') values are in the range of 0 - 2 kN/m2, while the effective friction angle (I$') are in the range of 17" - 3 lo. Tests using XRD concludes that the primary mineral in soft clay is quartz and the secondary mineral is kaolinite. On the other hand, XRF tests shows that the quantity of silica oxide and aluminium oxide are quite high in soft clay, which are due to the presence of kaolinite mineral. Test using SEM verified the presence of kaolinite mineral and pyrite in soft clay. From the correlation derived, it shows that the compressibility index increases with natural moisture content, Atterberg limit, initial void ratio and organic content. On the other hand, the effective friction angle is found to be influenced by the natural moisture content and plasticity index. The correlation obtained shows that the effective friction angle decreases with increasing natural moisture content and plasticity index