Environment
Kushai Caleb Aluwong; Mohd Hazizan bin Mohd Hashim; Suhaina Ishmail
Abstract
In the past, assessing water quality has typically involved labor-intensive and costly processes such as laboratory analysis and manual sampling, which do not provide real-time data. In addition to tasting bad, drinking acidic water on a regular basis can result in acid reflux and recurrent heartburn ...
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In the past, assessing water quality has typically involved labor-intensive and costly processes such as laboratory analysis and manual sampling, which do not provide real-time data. In addition to tasting bad, drinking acidic water on a regular basis can result in acid reflux and recurrent heartburn while high total dissolved solids water can cause kidney stones, especially when the hard water content is more than 500ppm. With growing concerns about water quality, there is a need for continuous monitoring of pH and TDS levels in surface and groundwater sources. To address this, a cutting-edge wireless sensor system leveraging on Internet of Things (IoT) technology has been developed. This system incorporates top-notch pH and TDS sensors known for their accuracy, durability, and environmental compatibility. Integrated with microcontrollers featuring wireless communication capabilities, these sensors enable seamless data transmission to a central server through IoT protocols like cellular networks. The collected data is processed and calibrated to ensure reliability and precision. The IoT platform connected to the central server manages device connectivity, data storage, and analysis, making real-time data accessible via user-friendly web or mobile applications with interactive graphs and dashboards. Power-saving features are implemented to optimize battery life in remote and off-grid locations, and weather-resistant enclosures protect the sensor nodes from harsh environmental conditions. By deploying this wireless-based sensor system, users can gain valuable real-time insights into water quality in surface and groundwater monitoring locations.
kausar Sultan shah; Naeem Abbas; Li Kegang; Mohd Hazizan bin Mohd Hashim; Hafeez Ur Rehman; Khan Gul Jadoon
Abstract
The rocks in the studied area are prone to deterioration and failure due to frequent exposure to extreme temperature variations and loading conditions. In the context of rock engineering reliability assessment, understanding the energy conversion process in rocks is critical. Therefore, this research ...
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The rocks in the studied area are prone to deterioration and failure due to frequent exposure to extreme temperature variations and loading conditions. In the context of rock engineering reliability assessment, understanding the energy conversion process in rocks is critical. Therefore, this research work aims to assess the energy characteristics and failure modes of pink and white-black granite subjected to uniaxial compression loading at various temperatures. Samples of pink and white-black granite are heated to a range of temperatures (0 °C, 200 °C, 400 °C, 600 °C, 900 °C, and 1100 °C), and their failure modes and energy characteristics including total energy, elastic energy, and dissipated energy are studied by testing preheated samples under uniaxial compression. The results show that the dissipation energy coefficient initially rises rapidly, and then falls back to its minimum value at the failure stage. The micro-structures of granite rock directly affect its elastic and dissipation energy. Axial splitting failure mode is observed in most of the damaged granite specimens. After heating granite to 600 °C, the effect of temperature on the failure mode becomes apparent.
Hafeezur Rehman; Ahmad Shah; Mohd Hazizan bin Mohd Hashim; Naseer Muhammad Khan; Wahid Ali; Kausar Sultan Shah; Muhammad Junaid; Rafi Ullah; Muhammad Bilal Adeel
Abstract
The major factors affecting tunnel stability include the ground conditions, in-situ stresses, and project-related features. In this research work, critical strain, stress reduction factor (SRF), and capacity diagrams are used for tunnel stability analysis. For this purpose, eighteen tunnel sections are ...
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The major factors affecting tunnel stability include the ground conditions, in-situ stresses, and project-related features. In this research work, critical strain, stress reduction factor (SRF), and capacity diagrams are used for tunnel stability analysis. For this purpose, eighteen tunnel sections are modelled using the FLAC2D software. The rock mass properties for the modelling are obtained using the RocLab software. The results obtained show that tunnel deformations in most cases are within the safety limit. Meanwhile, it is observed that the rock mass quality, tunnel size, and in-situ stresses contribute to the deformation. The resulting deformations also affect SRF. SRF depends on the in-situ stresses, rock mass quality, and excavation sequence. The capacity diagrams show that the liner experience stress-induced failures due to stress concentration at the tunnel corners. This study concludes that tunnel stability analysis must include an integrated approach that considers the rock quality, in-situ stress, excavation dimensions, and deformations.
Hafeezur Rehman; Wahid Ali; Kausar sultan Shah; Mohd Hazizan bin Mohd Hashim; Naseer Muhammad Khan; Muhammad Ali; Muhammad Kamran; Muhammad Junaid
Abstract
Support design is the main goal of the Q and rock mass rating (RMR) systems. An assessment of the Q and RMR system application in tunnelling involving high-stress ground conditions shows that the first system is more appropriate due to the stress reduction factor. Recently, these two systems have been ...
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Support design is the main goal of the Q and rock mass rating (RMR) systems. An assessment of the Q and RMR system application in tunnelling involving high-stress ground conditions shows that the first system is more appropriate due to the stress reduction factor. Recently, these two systems have been empirically modified for designing the excavation support pattern in jointed and highly stressed rock-mass conditions. This research work aims to highlight the significance of the numerical modelling, and numerically evaluate the empirically suggested support design for tunnelling in such an environment. A typical horse-shoe-shaped headrace tunnel at the Bunji hydropower project site is selected for this work. The borehole coring data reveal that amphibolite and Iskere Gneiss are the main rock mass units along the tunnel route. An evaluation of the proposed support based on the modified empirical systems indicate that the modified systems suggest heavy support compared to the original empirical systems. The intact and mass rock properties of the rock units are used as the input for numerical modelling. From numerical modelling, the axial stresses on rock bolts, thrust bending moment of shotcrete, and rock load from modified RMR and Q-systems are compared with the previous studies. The results obtained indicate that the support system designed based on modified version of the empirical systems produce better results in terms of tunnel stability in high-stress fractured rock mass conditions.
Kausar Sultan shah; Mohd Hazizan bin Mohd Hashim; Hafeez Ur Rehman; Kamar shah bin Ariffin
Abstract
The significance of rock failure can be found from the fact that microfracture genesis and coalescence in the rock mass results in macroscale fractures. Rock may fail due to an increase in the local stress, natural fractures, weathering inducing micro-crack genesis, coalescence, and propagation. Therefore, ...
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The significance of rock failure can be found from the fact that microfracture genesis and coalescence in the rock mass results in macroscale fractures. Rock may fail due to an increase in the local stress, natural fractures, weathering inducing micro-crack genesis, coalescence, and propagation. Therefore, a comprehensive understanding of the micro-scale failure mechanism of various weathering grade sandstones based on micro-level observation and microstructure-based simulation is essential. The microscale failure response of various weathering grade sandstones is studied under the wet and dry cycles. Each sample is tested for the micro-structure and micro-fracture characteristics using the image analysis. Furthermore, the micrographs obtained are also used to create the microstructure-based models, which are then simulated in the ANSYS software. The findings indicate that the moderately weathered sandstones indicate less weight reduction than the slightly weathered sandstone. The results obtained also demonstrate that the wet and dry cycles have little effect on the particle shape and size. However, variation in the particle shape and size implies that this is a result of the prevailing interaction of rock and water particle. The microscale simulation reveal that both UCS and BTS decrease from 37 MPa to 19 MPa and 9 MPa to 4 MPa as the density of the micro-structure increases. The results reveal that the primary fracture deviation from the loading axis increases with increasing density in the micro-structural micro-structures, although this effect reduces with further increasing density in the micro-structures.
K. Sultan shah; M. H. bin Mohd Hashim; H. Rehman; K. S. bin Ariffin
Abstract
Indirect tensile testing is used in order to investigate the effect of particle morphology (shape and size) on the various weathering grade sandstone fracture characteristics. Several fracture characteristics are discussed in depth in this work including the fracture length (FL), fracture deviation area ...
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Indirect tensile testing is used in order to investigate the effect of particle morphology (shape and size) on the various weathering grade sandstone fracture characteristics. Several fracture characteristics are discussed in depth in this work including the fracture length (FL), fracture deviation area (FDA), fracture angle (FA), and fracture maximum deviation distance (FMDD). A tabletop microscope (TTM) is used to measure the particle morphology. The image analysis techniques induce the uncertainty-related particle shape and size. Therefore, the Monte Carlo simulation (MCS) is used in order to incorporate the inherent uncertainties-related particle morphology. The results obtained reveal that the sandstone fracture angle presents an unclear relationship with the particle shape and size. The effect of particle size on FL is completely obvious, and FL increases with the particle size. In contrast, the particle shape and size have an unclear relationship with the fracture characteristics. Furthermore, the sandstone porosity affects the fracture characteristics, which increase with the weathering grade. Moreover, the findings reveal that the Monte Carlo simulation is a viable tool for integrating the inherent uncertainties associated with the particle shape and size.
K. Sultan Shah; M. H. Bin Mohd Hashim; K. Sh. Bin Ariffin
Abstract
The particles within the rock samples are present in extensive ranges of shapes and sizes, and their characterization and analysis exist with a considerable diversity. The prior research works have appraised the significance of the particle shape types and their effects on the geotechnical structures ...
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The particles within the rock samples are present in extensive ranges of shapes and sizes, and their characterization and analysis exist with a considerable diversity. The prior research works have appraised the significance of the particle shape types and their effects on the geotechnical structures and deficiencies by evaluating the uncertainty-related rock particle shape descriptors (PSDs). In this work, the Monte Carlo simulation (MCS) is used in order to present a framework to integrate the inherent uncertainty associated with PSDs. A tabletop microscope is used to measure the primary particle shape distribution for the sandstone samples. An open-source processing tool, ImageJ, is used in order to analyze PSDs. The probabilistic distribution of PSDs is acquired using MCS according to the relative frequency histogram of the input parameters. Additionally, a probabilistic sensitivity analysis is performed in order to evaluate the importance of the input parameters in PSDs. The sensitivity analysis results demonstrate that the major axis and area are the most influential parameters involved. The simulation results obtained have revealed that the proposed framework is capable of integrating the inherent uncertainties related to the particle shape.
K.S. Shah; M. H. Mohd Hashim; K.S. Ariffin; N. F. Nordin
Abstract
The stability analysis of rock slopes is a complex task for the geotechnical engineers due to the complex nature of the rock mass in a tropical climate that often has discontinuities in several forms, and consequently, in several types of slope failures. In this work, a rock mass classification scheme ...
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The stability analysis of rock slopes is a complex task for the geotechnical engineers due to the complex nature of the rock mass in a tropical climate that often has discontinuities in several forms, and consequently, in several types of slope failures. In this work, a rock mass classification scheme is followed in a tropical environment using the Rock Mass Rating (RMR) and Geological Strength Index (GSI) combined with the kinematic investigation using the Rocscience Software Dips 6.0. The Lafarge quarry is divided into ten windows. In the RMR system, the five parameters uniaxial compressive strength (UCS), rock quality designation (RQD), discontinuity spacing, discontinuity condition, and groundwater conditions are investigated. The RMR values range from 51 to 70 (fair to good rock mass), and the GSI values range from 62 to 65 (good to fair rock mass). There is a good and positive correlation between RMR and GSI. The kinematic analysis reveals that window A is prone to critical toppling, window H to critical wedge-planar failure, and window G to critical wedge failure. From the results obtained, it can be concluded that the kinematic analysis combined with the rock mass classification system provides a better understanding to analyze the rock slope stability in a tropical climate compared with considering the rock mass classification system individually.
