Journal of Sustainable Underground Exploration
Journal of Sustainable Underground Exploration (J-SUE) is an international, open access and peer reviewed journal which is published bi-yearly by Faculty of Civil Engineering and Built Environment (FKAAB), Universiti Tun Hussein Onn Malaysia (UTHM). The principle purpose of the journal is to publish scholarly work in the area of engineering that is in Geotechnics, Geology and Geophysics. J-SUE welcome article submission from the local and international researchers and practitioners in various related field. The research that is published should be original and unpublished results of conceptual, constructive, empirical, experimental or theoretical. Scope of Journal Engineering Geology Engineering Geophysics Rock Mechanics Soil Mechanics Ground Improvement Geoenvironment Mining and Tunnelling Geological Structure Petroleum Geoscience Geohazard Transportation Structure
Plaxis 2D Modelling of an Anchor Sheet Pile for Soil Slope Strengthening at Segamat, Johor
In soil engineering, the soil slope is one of the important issues in geotechnical and environmental engineering that can fail due to settlement behaviour. Due to soil slope instability, roads near the Segamat River’s slopes have seen severe settlement. Therefore, this study was carried out to determine how the geometry of the soil slope and the properties of the soil affect soil stability and deformation. Because of the varying slope geometries along the river, this study used two alternative slope geometries in its modelling. A comparison was made between the existing slope and the slope stabilised with sheet piling by using Plaxis 2D. Other parameters that affect slope stability are also being investigated, such as anchor length and anchor installation angle. The anchor sheet pile's presence is intended to improve the slope's stability. As a result of this analysis using PLAXIS 2D software, the optimal anchor length depends on the passive pressure of the soil behind the sheet pile. According to the results, installing an anchor with a 60° angle is more stable because the safety factor obtained is 3.26 which is greater than that of a 45° angle which is 1.33. It shows the anchor is the best support of the sheet pile for the soil slope stability.
Copyright (c) 2023 Journal of Sustainable Underground Exploration https://creativecommons.org/licenses/by-nc-sa/4.0
The Slope Failure of Weathered Granite Boulders by Using the Finite Element Method
An assessment of weathered granite profile of a research area at Mukim Senai, Kulai, Johor was conducted using PLAXIS 2D method. The slope stability of weathered granite is closely related to the geometric strength of the slope, slope height, soil type (sand or clay), slope gradient and depth to determine factor of safety. The aim of this research is to model and determine the factor of safety of the weathered granite slope with homogeneous characteristics using Plaxis 2D. In addition, it also aims to analyses and correlate the effect of shapes, size and distribution of boulders to the safety factor of the slope. Finite Element Method (FEM)) had been used through the application of PLAXIS 2D software. By comparing between the 2 methods that have been analyzed, safety factors for the slopes analyzed together with groundwater data is less safe. The Safety Factor has found less than 1.5 indicates a slope prone to landslides.
A Comparative Analysis of Mechanical Properties Between Granite and Basalt Rock Core Samples
Structural failure occurs when a load-bearing component of a structure fails to support and transfer loads to another element, leading to a breakdown in the performance of the materials in that structural component. The potential for structural failure is influenced by various variables, emphasizing the importance of understanding the behavior and parameters specific to rocks and soils in construction. In order to prevent failures in construction, engineers must possess a fundamental geological knowledge of rocks during the design process, recognizing the limitations of this construction material. Consequently, it is imperative to conduct tests to determine the precise strength of the rock being utilized. This study focused on granite and basalt, employing the Portable Ultrasonic Non-Destructive Digital Indicating (PUNDIT) test, Uniaxial Compressive Strength (UCS) test, and Brazilian test. The selected rock samples adhered to a diameter and thickness ratio of 1:2 or 2:1, depending on the specific test to be conducted. Density, compressive strength, and tensile strength of the rock samples were evaluated following the guidelines provided by the American Society for Testing and Materials (ASTM). The findings revealed that basalt exhibited higher density, compressive strength, and tensile strength compared to granite, with variations in results ranging from 13% to 40%.
Back Analysis and Potential Remedial Approach for Failure Slope at Bukit Nanas, Kuala Lumpur
This study aims to validate the design parameters and stability of the slopes failure and propose acceptable remedial work by assessing the slope stability in Bukit Nanas, center of Kuala Lumpur. The slopes’ height is around 40 and 60 m with the gradient around 30°-45°. Totally 7 boreholes be carried out and the pertinent engineering properties were analyzed from laboratory testing and back analysis (in situ test). An established computer program SLOPE/W was used to carry out for slope stability analysis. The analysis method adopted was Morgenstern-Price’s Method. Based on the result of the field investigation and numerical analysis, the model of lowest factor of safety (FOS) that evaluated from the existing slope in critical section were selected and recommended for remedial work. Two option of remedial slope design had been proposed. The first option is soil nailing with grid beam and proposed drain while the second option is hybrid anchor with grid beam and proposed drain. Both options are used to improve the slope stability, but first option had been chosen as higher FOS and more efficient option. This remedial approach based on the main cause of slope failure in Malaysia can applied as reference in future slope remedial design.
Deformation Characteristics of Lime Stabilized Marine Clay Using Finite Element Method
The coastal area is one of the environmentally vulnerable areas, with soil characteristics such as weak soil and marine clay, which is classified as hazardous soft soil. Because marine clay has poor mechanical and physical properties, foundation conditions such as pad footing were unstable and prone to corruption. As a result, the lime column will be used to stabilize marine clay in this study. The purpose of this research is to investigate the deformation of marine clay with lime to increase shear strength and reduce excessive settlement by analyzing data from previous studies and conducting a review of the literature, as well as to investigate the deformation of untreated and treated marine clay with lime columns and PLAXIS software projection. Compared to the traditional method, PLAXIS 2D software is one of the most cost-effective ways to test a foundation, such as the pad footing. At the same time, PLAXIS 2D was able to shorten the time required to achieve an analytical result. The results of the settlement and stress value have been taken after the computation and analysis from PLAXIS 2D. The greatest percentage difference between untreated and treated marine clay for stress and displacement is 81.82 percent and 7.98 percent, respectively.
Analysis of Geosynthetic – Reinforced Stone Piles – Supported Embankments
The low bearing capacity, high compressibility, and lack of lateral resistance of stone pile-supported embankments on soft clay deposits pose design challenges. To overcome these difficulties, geosynthetics have been widely favored by geotechnical engineers in recent years. A two and three dimensional (2D, 3D) finite element model study that simulates a geosynthetic-reinforced and geosynthetic-encased stone pile-supported embankment on soft ground is presented in this paper. To study the effect of reinforcement and encasing on the vertical displacement of stone piles and soft soil, numerical analyses are performed. The results show a significant reduction in settlement with the casing, which is believed to be a direct result of the additional containment pressure created by the geosynthetic casing. With the help of soil reinforcement, the surface settlement values ??of the soft soil could be significantly reduced.
Copyright (c) 2023 Journal of Sustainable Underground Exploration
Numerical Modelling of Tunnel-Ground Interaction with Building Existence
Tunnel is complex and risky construction. When excavation of tunnel take place, the original ground equilibrium will affected thus lead to the stress redistribution and ground movement. Tunnel construction in the urban city is in concerned as tunnel will passes under a lot of existing building. Therefore, in this study, a series of simulation of tunnel construction with and without external building was conducted. Numerical model by means ABAQUS Software was conducted based on tunnel-soil-load model was developed. From the result, it can be concluded that soil stress redistributed when excavation of soil occurs especially near to the tunnel periphery. The ground settlement trough depicts a significant maximum settlement for the model with high external load and producing flat u-shape in the middle of settlement trough pattern.
Marine Clay Soil Treated with Demolished Tile Waste: A Systematic Literature Review
This systematic literature review investigates the stabilization of marine clay soil using demolished tile waste. The study adopts the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) method to comprehensively analyze existing research in this area.The utilization of waste materials for soil stabilization has gained significant attention due to environmental concerns and sustainability objectives. In this review, we explore the effectiveness of using demolished tile waste as a stabilizer for marine clay soil. The analysis reveals that different types of waste materials exhibit varying degrees of improvement in the soil's properties. The results demonstrate a consistent increase in shear strength after stabilization, indicating the suitability of demolished tile waste as a stabilizing agent for soft clay soils. Interestingly, the highest strength is not obtained at the largest additive quantities. Instead, most research papers report a peak in strength at specific additive proportions and curing time, followed by a decline. This phenomenon occurs when the hydration process is complete, and large lumps form between the clay particles. Furthermore, the size of the additive also plays a crucial role in enhancing the strength of problematic soils. Optimal additive size leads to better distribution and interaction with the clay particles, contributing to improved stabilization results. This review provides valuable insights into the potential of utilizing demolished tile waste for enhancing the engineering properties of marine clay soil. The findings highlight the importance of carefully selecting the type and quantity of additives to achieve the desired stabilization outcomes.
Impact of Sugarcane Bagasse Ash (SCBA) and Cement to the Strength Improvement of Hemic Peat
Peat soils are derived from organic deposition consisting of dead trees. Peat soils have low shear strength and cannot afford large loads. Various treatment methods are used to stabilize peat soils and most of them use cement as a main binder to increase the strength of peat soils. However, the use of large quantities of cement is not environment friendly due to the release of carbon dioxide (CO2) and wastage of energy consumption by the cement production industry. Therefore, the introduction of SCBA as a substitution binder for some cement dosage is good as well as reducing the degradation of dumping waste which is increasingly uncontrollable. The objective of this study is to identify the basic and physical properties of peat soil from Pontian, Johor. In addition, this study was also conducted to identify the impact of SCBA on peat soil stabilization with cement. There are 5 different mixtures for cement and SCBA which are C100, C95S5, C90S10, C85S15 and C80S20 used in this study. Sample C95S5 with mixtures 95% cement and 5% SCBA were the optimum samples for this study based on unconfined compression strength (UCS) tests. The C95S5 sample successfully achieved the maximum strength of the whole sample with a strength of 190 kN/m2, 209 kN/m2, and 219 kN/m2 recorded for wet curing periods of 7,14 and 28 days. Therefore, the use of SCBA materials in the stabilization of peat soils with cement and calcium chloride (CaCl2) is seen to have a positive effect in increasing the shear strength of Hemic peat soil samples.
Peat soil, Cement, Sugarcane Bagasse Ash (SCBA), Unconfined compressive strength (UCS)
Correlation of Electrical Resistivity Tomography and Geotechnical Field Data for Soil Profile Characterization
This study looked at the effects of compaction on resistivity values as well as the relationship between different degrees of compaction. The material used in this experiment was laterite soil. The sample was tested into a standard proctor mould. The model has 10.20cm diameter and 11.6 cm for height of the mould. Each sample's resistivity was measured entirely compacted.The resistivity testing in this study were conducted using the Miller 400A. ASTM D 422 Standards were used, and for electrical resistivity testing, ASTM G57 is used. This research emphasises the impact of moisture content on resistivity value, as soil reduces resistivity value when the soil has higher moisture content which is 120 ?m at 37%, and 190 ?m at 25%. By comparing the results of different moisture content of soil samples under varied degrees of compaction, better resistivity interpretation tables may be generated.
Compressibility Behaviour On Carbonation of Ground Granulated Blast Furnace Slag (GGBS) Treated Kaolin
With the growing worry over pollution in the environment, the necessity to comprehend this phenomenon has multiplied. Not only that, the economic gain made in the last decade, along with the fast growth of the world population, has come at a huge environmental cost. One of the never-ending issues is carbon dioxide emission and notably, the construction sector is no exception to mean to contribute through many development activities. Therefore, this study focuses on the compressibility behaviour of Ground Granulated Blast Furnace Slag (GGBS) treated kaolin clay due to carbonation. This study discusses the effect of carbonation on GGBS-treated kaolin as an effort to use sustainable materials which able to improve the geotechnical properties of soil and safe to say, help to reduce the emission of CO2. Testing program via one-dimensional consolidation test found that the compressibility characteristics improved as increased the GGBS content. Overall, the results illustrate that higher GGBS content and longer curing period gives lower compressibility characteristic. It was also found that the carbonated kaolin sample further improve the compressibility characteristics as compared to ambient condition of treated kaolin sample. In conclusion, GGBS can improve the compressibility characteristic of kaolin with carbonation consideration.
Kaolin, Strength, Granulated Grounded Blast Furnace Slag (GGBS), Carbonation, Consolidation
A Numerical Investigation for In-Situ Measurement of Rock Mass Mechanical Properties with a CCBO Probe and Evaluation of the Method’s Error in Estimating the In-Situ Stresses with the Overcoring Technique
Accurate determination of rock stress in great depths has become one of the most critical issues in civil and mining affairs along with the expansion of underground excavation spaces’ scale and deepening of under-excavation areas. The hydraulic fracturing method and coring-based laboratory methods including ASR, DSCA, and AE are main techniques in rock stress measurement in the earth’s depth. Thus far, previous studies have reported repeated samples from the values obtained from the above mentioned techniques. Nonetheless, the “Compact Conical Borehole Overcoring” (CCBO) technique is an example of the stress-relief method and this technique, is one of the most cost-effective and accurate methods for measuring the in-situ stresses simply by digging one borehole either in the tunnels’ wall or in the deep wells’ depth. The current study aims at analyzing the overcoring technique with the CCBO probe to identify errors regarding the number of sensors installed, as well as checking its ability to estimate mechanical parameters of mass rock in-situ. In this study, we have utilized the analytical method based on numerical simulations to determine the accuracy of the method’s dependence on the number of sensors installed on the probe. We performed numerical analysis using COMSOL finite element software, as well as MATLAB software. In addition, we attempted to propose possible relations for estimating mechanical parameters of mass rock using the probe, a method determined by the inventors.
Copyright (c) 2022 Journal of Sustainable Underground Exploration
The Effect of Compaction Towards Resistivity Value
Electrical resistivity tomography is a non-destructive method of site investigation that involves injecting electricity into the sample and measuring subsurface resistance. This study looked at the effects of compaction on soil as well as the relationship between different degrees of compaction of soil and resistivity value. The soil used in this experiment was lateritic soil. The sample was compacted in a standard proctor mould with a diameter of 10.20cm and 11.6 cm height. The soil’s resistivity was measured after the soil was compacted inside the mould. The resistivity testing was conducted using soil resistivity meter model Miller 400A. ASTM G57 was used for electrical resistivity testing. This research emphasizes the impact of compaction on resistivity value, as soil reduces resistivity value when the soil has higher moisture content which is 120 ?m at 37%, and 190 ?m at 25%. By comparing the results of different moisture content of soil samples under varied degrees of compaction, better resistivity interpretation tables may be generated.
Effect Of Soil Shear Strength on Shoreline Changes at Batu Pahat Coastal Area
This study focuses on the effect of soil shear strength due to the shoreline changes in Batu Pahat Coastal Area. The shorelines of Pantai Punggur were chosen as the subject location for this investigation on soil shear strength and shoreline changes of eroded areas in Batu Pahat, Johor. Pantai Punggur is situated on the west coast of Johor, with a latitude of 1.62° to 1.87° N and a longitude of 102.78° to 103.19° E. Aerial photographs and field observation data were used to determine the geomorphological components of the Pantai Punggur shoreline using an unmanned aerial vehicle (UAV). The study conducted is to produce shoreline changes mapping diagram and analysis soil shear strengths across different sampling locations were measured and correlate with shoreline changes at zones A, B, C, D and E. The aerial image that has been captured by the drone was analyzed using Pix4D and Global Mapper software. Based on the data of shoreline changes zone A portrays the highest changes followed by zone B and C. As for zone D and E its shows quite a small change. Within one month interval, Pantai Punggur coastline experiences changes in about 1.57 meters. From the undrained shear strength test at 0.5 m depth at HT and MT data for December 2021, zone A with Cu reading are more than 4.5 kPa followed by zones B, C, D and lowest at zone E. Next, at depth 0.5 m and 1.0 m data for December 2021 at HT level, zone A with Cu reading is more than 4.5 kPa at the 0.5 m and 1.0 m depth and other zones are below than 3.0 kPa. The depth of soil also influences the data of this study. The correlation of changes in soil shear strength with shoreline changes is reported to have a linear correlation with R2 value is 0.9261. It can conclude that the effect of soil shear strength on shoreline changes at Batu Pahat coastal area cause by the changes in soil shear strength (Cu) gives a large effect of shoreline changes.
Soil strength, coastal shoreline, shoreline changes, coastal erosion
Optimum Design of Oil Tank Foundation on Different Soil Conditions
Tank foundation is a base for the tank which is designed to support the weight of oil tanks and contain spillage. Other than that, tank foundation failure usually occurred when the foundation system cannot support the weight of the tank or the soil in that area is not improved, and failure of tank foundation can lead to pivoting effect and cracking on the foundation slab. This study aims to determine the deformation characteristics of foundation slab of oil tank foundation and evaluate the performance of oil tank foundation on different soil conditions. The oil steel tank with dimension of 27.68 m in diameter and 12 m high with 2000 kN of load was chosen from A Case Study of Study on Design of Ring Footing for Oil Storage by Alkhuzaie (2018). However, manual calculation for the slab thickness, pile cap self-weight, pile spacing, pile capacity and number of require pile were calculated manually as shown in appendix 2. Series of analysis with a finite element model was conducted using STAAD Foundation CONNECT Edition V9 was to analyse the foundation structure, observed the soil bearing capacity sensitivity and deformation characteristics of the foundation slabs. Three types of foundation (raft, pile raft and pile foundation) were designed in STAAD Foundation CONNECT Edition V9. From this study, the most optimum design for foundation structures with different soil conditions was obtained which are raft foundation structure is the most appropriate to construct on residual soil. In addition, pile raft foundation structure is the most appropriate to construct on marine sediment deposit while pile foundation structure on peat soil.
The Effect of Groundnut Shell Ash on Soil Stabilization
The purpose of this study was to focus on how the groundnut shell ash affect the soil stabilization. Groundnut shell ash was used in this study to replace the excessive reliance on industrially created soil enhancing chemicals (cement, lime, and so on) has kept the cost of stabilizing a road high. It was determined that groundnut shell ash may be used and effective as a soil stabilizing component after studying the stabilization of black cotton soil using groundnut shell ash. The ideal usage of groundnut shell ash applied to the soil is 6 percent. Particularly in engineering projects on poor soils, where it may be utilized to replace deep/raft foundations, groundnut shell ash and waste fibre reinforced soil can be an excellent ground improvement option. This can save both money and energy. The process of stabilizing foundation soils to attain desired characteristics or to improve the strength and durability of a less stable soil is known as stabilization. Differential expansion and contraction are possible when a soil's moisture content fluctuates. It is usually required to stabilize them in order to lessen volume fluctuations and strengthen them so that they can withstand the applied loads even when saturated.
Groundnut Shell Ash, soil’s stabilization, ground improvement, soil’s improvement, soil’s moisture, soil’s strength, soil’s durability
Numerical Modelling of Soft Soil Improvement Using Expanded Polystyrene Geofoam for Road Embankment
Soft soil brings abundant engineering issues due to low bearing capacity and shear strength. A comprehensive study of soft ground needs to be reviewed and identified before construction can start. Various techniques can be used to improve the soil. However, this study focuses on using material, namely expanded polystyrene. The geotextile is embedded with expanded polystyrene to strengthen the soil condition. This study adopted the soil parameters from East Coast Expressway 2. There are two models in this study, which are earth embankment and EPS embankment. The settlement of the earth embankment is compared with the EPS embankment after construction. The Mohr-Coulomb parameters are used to model soft soil and embankments, while the linear elastic parameters were adopted to model the EPS and geotextile. This study produced two embankment models, the conventional embankment models with and without surcharge. The second model is an EPS embankment with various densities (22 kg/m3, 29 kg/m3, and 39 kg/m3). The settlement is recorded for ten years after the embankment construction was completed. The difference settlement value for the conventional model is 28 mm. The settlement value for EPS 22 is 3.18 mm, EPS 29 is 2.06 mm, and EPS 39 is 1.51 mm. For the geotextile embedded with EPS settlement value, EPS 22 is 3.17 mm, EPS 29 is 2.04 mm, and EPS 39 is 1.49 mm. Since EPS uses three different densities, from the prediction of PLAXIS 2D, the higher density gives the lower value of the settlement. However, when the geotextile is embedded with EPS, there is no significant difference when using geotextile. In conclusion, the model with a surcharge gives a lower settlement than the model without a surcharge. But the expanded polystyrene block is the best model to reduce the settlement compared with the conventional model with a surcharge. Different density of EPS gives different settlement value, and EPS 39 gives the lowest settlement value. In terms of the geotextile embedded with EPS, it does not give a significant settlement.
Soft Soil, PLAXIS 2D, EPS, Soil Improvement
Effect of Surcharges to The Stability of Mechanically Stabilized Earth Wall Using Finite Element Method: Back Analysis Study Case in Senai City Airport
Abstract: Mechanically Stabilized Earth (MSE) wall is a composite retaining structure construction made up of alternating layers of compacted backfill and soil reinforcing components. Surcharges on top of MSE wall is one of the factors that can lead to the failure of the MSE wall. In Senai City Airport, a MSE wall with high 9 m and length up to 400 m has been constructed. However, the effect of various surcharges of the MSE wall slope did not well investigate and was poorly understood. This study aims to investigate the effect of surcharge to the stress behaviour and the factor of safety of Mechanically Stabilized Earth Wall (MSE) wall using Finite Element Method (FEM). The study conducted using different loads in order to determine the stress behaviour and the safety factor of MSE wall using PLAXIS software. The geometry and parameters of sandy silt slope of Senai City Airport, Senai, Johor was taken from design consultant and previous soil investigation report, respectively. The soil parameters were used in this study are the unit weight of the soil, cohesion, Poisson Ratio, Young Modulus and the friction angle. This study gave the best result in order to determine the effect of surcharges to the behaviour of stress and safety factor of MSE wall. The highest total displacement was at 100 kN with total displacement 19.23m with 0.884 factor of safety. This study revealed the effect of various surcharges on the behaviour of stress and factor of safety of the MSE wall. The increase of surcharge increased the stress behind the wall and increased the factor of safety (FOS) when the loads was increased.
Deformation Characteristics of Lime Stabilized Clay Soil Using Finite Element Method
Clay soil provides a poor working platform due to its plastic characteristics that could affect a structure’s safety and other common structure failure including excessive foundation settlement, the production of cracks in the superstructure and other structural element failure. Thus, there is a challenge for clay soil to be a support for a foundation. The objective of this study is to compile a set data from past research studies that include the parameters of untreated and treated clay soil properties as to be used in the PLAXIS 2D generate its deformation over no load and 100 kPa stress as well as increasing its shear strength and reduce the excessive settlement. Accordingly, the suitable lime content to improve clay strength can be determined. The numerical analysis is done by running the parameters collected from previous studies in PLAXIS 2D in order to generate the final deform soil. The soil with lime content 0%, 3%, 6%, and 9% deformed under both without and with loading of 100 kPa. The result that can be observed from the deformed soil, the treated clay behaved well under loading compared to the untreated. From the result, the amount of lime content did affect the properties of the soil by showing the settlement of each soil and the deformation pattern.
Clay Soil, Foundation, Lime Content, PLAXIS 2D
The Influence of Mineralogy Towards Electrical Resistivity Value and Cation Exchange Capacity
Electrical Resistivity Tomography (ERT) is a method used for subsurface profiling in soil. The subsurface profile characterization determines the layer, thickness, soil lithology, presence of groundwater, fracture zones, variations in soil saturation, areas of increased salinity, or groundwater contamination. The value of the subsurface resistivity is determined by using electrical resistivity method (ERM). Multiple factors may influence the analysis results of the electrical resistivity method (ERM), especially the particle size distribution, porosity, mineralogy, density, cation exchange capacity (CEC), and water content. Hence the aim of this study, which was to evaluate the effects of cation exchange capacity (CEC) towards the electrical resistivity values (ERV). The objectives of this study were to characterize index properties of artificial silt and clay at different CEC values, to identify the effect of minerals towards ERV and CEC value, and to establish the correlation of the artificial silt and clay, moisture content, and CEC with the ERV. Samples used in this study were kaolinite, montmorillonite, illite, quartz, mica, and feldspar, passing 0.063mm sieve. Basic soil index properties, i.e., particle size distribution, specific gravity, porosity, and Atterberg limit were determined refering to BS 1377 (1990). A Terrameter LS 2 with a soil resistivity box were used in determining the ERV, whereas Atomic Absorption Spectroscopy (AAS) with ammonium acetate solution to determine the CEC. Porosity obtain from this study were between 0.5 to 0.6. Comparison of mineral based on the ERV obtained shows kaolinite contains the highest resistivity value followed by feldspar, quartz, mica, illite and montmorillonite respectively. The lowest to highest CEC mineral are kaolinite, feldspar, quartz, mica, and illite montmorillonite. These values can correlate between resistivity versus CEC, which shows that the higher the ion exchange, the higher the electrical conductivity of the sample.
Copyright (c) 2021 Journal of Sustainable Underground Exploration
Stabilization of Johor Peat Soil using Sugarcane Bagasse Ash (SCBA)
Peat soil have been categorized as a problematic organic soil, because they have a high settlement rate when placed any structure on it. Therefore, the peat soil must first be stabilized using cement before it can be used. However, massive use of cement can lead to environmental pollution. Therefore, this study intends to use sugar cane bagasse ash as a substitute for cement in peat soil stabilization. The mix ratio of 5% to 20% was used to find the optimal mix ratio. Various tests were carried out on samples such as basic properties tests, Unconfined Compressive Strength (UCS) and Scanning Electron Microscope (SEM). After all the tests, the 5% replacement SCBA mix ratio gave the highest unconfined compressive strength if compared to the other mixtures ratio. Therefore, it is selected as the optimum mix ratio. The soil strength achieved by the SCBA 5% replacement ratio was found to be higher than cement stabilization alone due to the presence of secondary pozzolan reactions. The microstructure result from the SEM test had shown that the 5% replacement SCBA mix ratio filled in the hollow left by the peat soil. Hence, able to improve its soil structure and thus increasing its strength.
Review on Soil Improvement by Using Various Chemical Additives for Foundation
This work aimed to study the most effective chemical additives to increase the strength of the clay soil. The problem statement is to improve the soil strength to avoid failure in the ground. The chemical additives that be used are lime, cement, and fly ash. These chemical additives were commonly used to stabilize the soil and make the shear strength of the soil increase. The data taken was from the previous research, where the data was compared to get the most effective chemical additives to improve the soil stability and soil strength. The percentage of the chemical additive used in the soil mixture was 8% to 10%. The data from previous research was chosen based on the rate used of the chemical additive and the research was taken from Science Directed website only. Data were collected through 30 previous studies using clay and chemical additives such as cement, lime, and fly ash. The data for Plastic Limit, Liquid Limit, Plasticity Index, Optimum Moisture Content, Maximum Dry Density, and Unconfined Compressive Strength was taken by referring to the previous study. Then the data was listed in Microsoft Excel to generate the graph for comparison. All the data obtained are then compared to get which chemicals can increase the strength of the soil. The result of this study shows that the cement was the most effective chemical additive to improve the soil strength and to stabilize the soil than the lime and fly ash.
Groundwater Pathway Mapping Using Electrical Resistivity Tomography (ERT) Method
Geophysical electrical resistivity method has been one of the more popular non-destructive method to explore the subsurface. Geophysical electrical resistivity tomography (ERT) subsurface profiling was conducted to map the groundwater path along the embankment. The groundwater path able to decrease the slope stability, thus its need to locate the position for conduct the slope remediation via subsoil drainage. In this study, Terrameter LS2 model, electrodes, cables, battery, and cable connectors were the equipment used for measurement. This study uses cable spread line at 200m with 2.5m spacing between electrodes by using gradient protocol. The resistivity data was analyzed using RES2DINV software. The interpretation of groundwater path is based on the resistivity values less than 100 ohm.m, which is interpreted as saturated materials. This study demonstrates the efficiency of application of electrical resistivity tomography (ERT) in detecting the groundwater pathways. This investigation will help in sustaining the slope stability via indicating the position of groundwater pathways, and thus implementing the slope remediation work.
Assessment of Tube Well Pumping Test Performance on Different Geological Formation
Water supply-demand is increasing in line with the increment in population. Natural water resources are declining due to a few factors of a reduction of water catchment areas, river pollution and drought. This causes the raw water quantity to decrease and its quality to be contaminated and resulting in higher water treatment costs. Groundwater usage is able to solve this problem due to its less pollution and requires minimal water treatment. The groundwater is preserved in aquifer within the geological formations, i.e., in the alluvium and fractured rock. However, the groundwater yield of each formation is unknown unless constructing the tube well and performed the pumping test. The study aim is to evaluate the tube well performance via pumping test on different geological formations. This research focuses on the effect of transmissivity, hydraulic conductivity, and efficiency of the aquifer, which are step-drawdown test, constant-rate test and recovery test in tube well in the geological formation of alluvium and fractured rock. Three well-pumping tests at each formation of alluvium and fractured rock were conducted at IBS Universiti Malaysia Kelantan (UMK), Kelantan, Sekolah Kebangsaan Chantum, Kelantan, Sekolah Menengah Kebangsaan Agama Tok Bachok, Kelantan, FRU Wakaf Tapai, Terengganu, Kampung Dada Kering, Kuala Lipis, Pahang, and Kampung Seri Gunung Pulai, Johor, respectively. The aquifer efficiency is obtained from the relationship between transmissivity and hydraulic conductivity. The suggested value of 75% efficiency is selected for presenting its well efficiency. The wells efficiency indicate that the alluvium formation was constantly higher between 9.39m3/h and 23.38m3/h. Meanwhile in the fractured rock formation were highly varied between 1.00m3/h and 32.33m3/h. The alluvium aquifer showed uniform water production compared to the fractured hard rock aquifer. Meanwhile, the water quantity in the fractured hard rock formation is unpredicted, which is subjected to the fractured rock characteristic.
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.
Forensic Study on Federal Road Pavement Failures at Rengit and Semerah, Batu Pahat
Forensic investigations in engineering term may be conducted to identify the causes of failure to facilitate the design of proper repairs, or to improve the performance or lifespan of a component, assembly, or structure. This paper presents the combination of geotechnical investigation and geophysical survey method as a forensic tool to predict the causes of pavement failure occurred along the coastal area of federal road FT005. The number and type of field testing are varying on each selected study area at Rengit and Semerah, Batu Pahat as this location constructed on soft soil area. Non-destructive testing (NDT) method using electrical resistivity tomography (ERT) were chosen to be applied at the worst severity of the road failure. Three number of resistivity lines of 100m and 200m were laid out using ABEM Terrameter LS2 with gradient method of electrode arrays covering up to 40-meters depth. Then, further testing of destructive testing (DT) method using borehole drilling conducted near the ERT lines to obtain soil profile with SPT N-value measurement. The disturbed and undisturbed samples were obtained to carried out laboratory test for soil classification. After that, visualization of road pavement layers was implemented via five number of trial pit test which were excavated up to subgrade layer to determine the thickness of the materials used in road construction. Three number of mackintosh probe test were also conducted on top of the subgrade layer after the trenching to obtain the strength of the subgrade layer. The results presented showed that severe longitudinal cracking were the predominant premature failures on the roads studied. This were found caused by settlement effect from the road subsidence from soft soil layer. The analysis obtained from RES2DINV program stated that the subsurface profiling was dominantly in saturated condition which the resistivity value was less than 100 ohm.m. From the SPT N-value it is observed that, the very soft soil layer is up to 8 m at it profile changes with depth from soft to stiff clays soil up to 40.5m. Another causes of failure were resulted from the differential settlement due to the effect of different design of road construction with varies material used. The reliability and efficiency of the instruments used were also discussed in this study.
Geological Terrain Mapping using Geographic Information System (GIS) and Drone Photogrammetry
The research area was conducted within the Bukit Persekutuan, Kuala Lumpur, and it was located at the latitude 3° 8'32.93"N and longitude 101°40'32.80"E. The researcher carried out geological terrain mapping to evaluate the research area in accordance with the geological terrain classification attributes of each thematic map produced, namely, Terrain map, slope gradient map, erosion, and instability map, as well as construction suitability map. The occurrence of landslide events within the research area becomes a major contributing factor to thoroughly conducting an investigation by field mapping and analysing using the Geographic Information System (GIS) technology. The application of Geographic Information System (GIS) and drone photogrammetry images play an essential role to analyze and processing the data, thus, generate the thematic maps. The research area indicates that about 79.11% of the overall area was not appreciable with erosion, 8.58% contribute to the erosion, 11.00% of recent general instability and 2.97% represent a landslide event. The suitability for development mapping illustrated Class I (23.40), Class II (36.37%), Class III (26.39%), and Class IV (15.50%) where it can be referred to the construction suitability classification system, the suitability for development was high in class I, moderate in class II, low in class III and not suitable in class IV.