229 research outputs found
Use of slag (with cement) for improving the performance of expansive soil of road pavement subgrade
The study presented in this paper evaluates the suitability of using slag (with cement) as a stabilizer, for improving the performance of expansive subgrade soil in road pavement. Several laboratory tests were conducted to determine the geotechnical engineering characteristics of the expansive soil and associated mechanical engineering performance. The tests conducted include the particle size distribution, standard Proctor compaction, Atterberg’s limits, free swelling, permeability, California bearing ratio (CBR), unconfined compressive strength (UCS), and repeated load triaxial (RLT). In this study, the use of slag (with cement) as a stabilizer followed three proportion schemes, and the selection of a specific stabilizer proportion was determined based on UCS value that satisfies the required standard as a subgrade for road pavement. The results recommended a stabilizer proportion for the soil studied to be 13.5% slag + 1.5% cement at 28 days curing time. This mixture resulted in a remarkable increase in the UCS value of eight times higher than the UCS value of the non-stabilized soil. The CBR value of the mixture was four times higher than the minimum required value for design of road pavement. The study presented herein confirmed that the exploitation of the by-product material of slag can indeed be useful, both in terms of improving the performance of the subgrade soil for road pavement and sparing the environment a spread of significant potential pollutant
Experimental Investigation into Multistage versus Conventional Triaxial Compression Tests for a c-phi Soil
The procedure for conventional triaxial compression (CTC) test requires three separate soil specimens to be examined to failure under different confining pressures so that Mohr-Coulomb (or stress path) failure envelope can be determined and soil shear strength parameters can be obtained. An alternative procedure is the multi-stage triaxial (MST) compression test, which requires only one soil specimen to be tested at three stages of shearing with different confining pressures. There are several advantages for using MST over CTC, which apart from fewer soil specimens, include less laboratory time consumption and reduced effects of heterogeneity among the specimens tested. However, it has been argued in the literature that the advantages of using MST may be compromised by its inability to obtain reliable soil behavior or accurate shear strength parameters. In this paper, the accuracy of MST compared to CTC is investigated for a c-phi soil, and a simple procedure that can be adopted to rectify the MST results is proposed
TSUNAMI AFFECTED COASTAL SOIL DISTURBANCE AND IMPLICATIONS ON RECONSTRUCTION WITH SPECIAL REFERENCE TO LOW-COST DWELLINGS AND RAIL TRACKS
TSUNAMI AFFECTED COASTAL SOIL DISTURBANCE AND IMPLICATIONS ON RECONSTRUCTION WITH SPECIAL REFERENCE TO LOW-COST DWELLINGS AND RAIL TRACKS
Load-settlement modelling of axially loaded drilled shafts using CPT-based recurrent neural networks
The design of pile foundations requires good estimation of the pile load-carrying capacity and settlement. Design for bearing capacity and design for settlement have been traditionally carried out separately. However, soil resistance and settlement are influenced by each other, and the design of pile foundations should thus consider the bearing capacity and settlement inseparably. This requires the full load–settlement response of piles to be well predicted. However, it is well known that the actual load–settlement response of pile foundations can be obtained only by load tests carried out in situ, which are expensive and time-consuming. In this paper, recurrent neural networks (RNNs) were used to develop a prediction model that can resemble the full load–settlement response of drilled shafts (bored piles) subjected to axial loading. The developed RNN model was calibrated and validated using several in situ full-scale pile load tests, as well as cone penetration test (CPT) data. The results indicate that the developed RNN model has the ability to reliably predict the load–settlement response of axially loaded drilled shafts and can thus be used by geotechnical engineers for routine design practice
Factors Affecting Quality of Life in Patients with End Stage of Renal Disease on Hemodialysis , Ras Al Khaimah-United Arab Emirates
Background: Nowadays, a dramatically increase on the incidence and prevalence of End Stage Renal Disease (ESRD) were more than one million ESRD suffer worldwide, thus, ESRD is an important public health concern for it has considerable repercussion on the quality of life (QoL) of patients and the community’s increased social and health care needs. Purposes: Were to describe the quality of life in patients with end stage of renal disease on hemodialysis and to examine the contributing factors that may affect quality of life. Methodology: A cross sectional design was used to describe the QoL in patients with ESRD on hemodialysis and to determine the contributing factors that may affect quality of life; and a correlational design was utilized to examine associations among the independent variables (demographic characteristics and biological factors) that may influence the dependent variable (QoL). Setting of the study: It was at dialysis unit located in Ibrahim Bin Hamad Obaidulla Hospital (IBHOH), affiliated to the Ministry of Health , Medical District in Ras Al-Khaimah Emirate - UAE which provided the medical services to all patients regularly attending the in-patient hemodialysis (Emirates citizens and Non- Emirates citizens) and were managed by medical and paramedical staff working within the same hospital. Sampling: A purposive sampling was conducted and the accessible population was comprised of 129 regular patients. Out of 129 patients, 74 patients were qualified in the inclusion criteria to participate in the research. Participants were interviewed individually to measure Health Related Quality of Life (HRQoL) using Kidney Disease Quality of Life-36TM (KDQoL 36TM) scale and compared KDQoL scores by demographic factors, and biological factors. Results: the overall quality of life of patients with ESRD on hemodialysis was low, with M+SD(39.57+16.13). Increase poor quality was independently associated with female gender, aged >60 years, low educational level, unemployment status have poor QoL. The Physical Component Summary (PCS) domain came in the first rank with the lowest rated and scored with M+SD (32.66+17.30), whereas the mean of the Burden of Kidney Disease domain came in second rank with M+SD (34.61+12.26). Meanwhile, the Symptoms and Problems domain came in third rank with M+SD (38.56+22.8), followed by the Effects of Kidney Disease on Daily Life domain that came in fourth rank with M+SD (42.22+10.56), and then lastly, Mental Component Summary (MCS) domain came in fifth rank with M+SD (49.84+17.73). In this study, the results revealed that the level of serum albumin and gender were the most significant predictors that influence QoL in patients with (ESRD) undergoing hemodialysis at (P>0.05). Conclusion and Recommendation: The results of the present study shown the evidence that patients with ESRD have poor QoL. Lowest score of KDQoL 36TM scale was found in the "PCS , while highest score was MCS. Furthermore , the study revealed that level of the serum albumin was the most significant predictor influence QoL in patients with ESRD and the most modifiable factor which has a strong association with poorer HRQoL was education, whereas non-modifiable factor was female gender. Because of those factors attention should be given to the nurses and other health care providers as formal caregivers for early interventions that prevent further morbidity and minimize the mortality as well as provide the evidence-based for clinical practice that assist the nurses to have a comprehensive assessment of their patients’ lives and integrated all these crucial aspects in inclusive plan for appropriate nursing intervention and improve quality of patient’s life and HRQoL. Keywords : End stage renal disease, hemodialysis, Quality of lif
Stabilisation of Clay with Fly-Ash Geopolymer Incorporating GGBFS
Abstract -Low water/binder ratio and higher activator content can help to accelerate the setting and strength development of fly-ash geopolymers cured at ambient condition. This study aims to achieve clay stabilization with fly-ash based geopolymer incorporating ground granulated blast-furnace slag (GGBFS), to enhance soil strength performance at ambient temperature. Laboratory experiments were performed on clay samples stabilized with both slag and fly-ash geopolymer and ordinary Portland cement (OPC), including the soil plasticity, compaction and unconfined compressive strength. The investigation was expanded to include un-activated fly-ash/slag clay samples used as control mixtures. The results indicated that introducing GGBFS to class (F) fly-ash based geopolymer assists, when synthesised in certain concentrations, in achieving a setting time and compressive strength comparable to OPC stabilised clay
Explore the E-Learning Management System Lower usage during COVID-19 Pandemic
During the COVID-19 pandemic, several universities are finding it difficult to provide and use online and e-learning systems. Blackboard, for example, is an e-learning system with various wonderful features that would be useful during the COVID-19 pandemic. However, knowing the acceptance variables as well as the primary problems that contemporary e-learning technologies confront is crucial for efficient utilization. The growing number of students attending different instructional organizations has resulted in a greater volume of material being needed in these organizations both from the academic and professional workforce and also because learning management systems and e-learning are indeed the university prospect, several more universities and colleges have accepted them. The purpose is to analyze the most popular E-learning system, the Blackboard system, and the authors suggest a learning management control system to accommodate major e-learning features. A Blackboard system is a plethora of academic perspectives, research, ideas, theories, and affective responses to the virtual learning environment. To use it, the technology acceptance model in times of crisis (TAMTC) has been developed as a way to evaluate student acceptability. The existing literature demonstrates that the field of information administration is constantly changing due to the effect of learning technologies like the blackboard system. Given their reduced utilization of the system, the data reveal a high level of student acceptability. The conclusions of this study provide important recommendations for policymakers, managers, developers, and academics, allowing them may further understand the key factors of successfully using an e-learning system during the COVID-19 epidemic
Explore the E-Learning Management System Lower usage during COVID-19 Pandemic
During the COVID-19 pandemic, several universities are finding it difficult to provide and use online and e-learning systems. Blackboard, for example, is an e-learning system with various wonderful features that would be useful during the COVID-19 pandemic. However, knowing the acceptance variables as well as the primary problems that contemporary e-learning technologies confront is crucial for efficient utilization. The growing number of students attending different instructional organizations has resulted in a greater volume of material being needed in these organizations both from the academic and professional workforce and also because learning management systems and e-learning are indeed the university prospect, several more universities and colleges have accepted them. The purpose is to analyze the most popular E-learning system, the Blackboard system, and the authors suggest a learning management control system to accommodate major e-learning features. A Blackboard system is a plethora of academic perspectives, research, ideas, theories, and affective responses to the virtual learning environment. To use it, the technology acceptance model in times of crisis (TAMTC) has been developed as a way to evaluate student acceptability. The existing literature demonstrates that the field of information administration is constantly changing due to the effect of learning technologies like the blackboard system. Given their reduced utilization of the system, the data reveal a high level of student acceptability. The conclusions of this study provide important recommendations for policymakers, managers, developers, and academics, allowing them may further understand the key factors of successfully using an e-learning system during the COVID-19 epidemic
Utilization of lime for stabilizing soft clay soil of high organic content
This paper presents the results of geotechnical and mineralogical investigations on lime-treated soft clay soil from Idku City, Egypt, where high organic matters of about 14% exist. Lime was added in the order of 1, 3, 5 and 7% by weight and laboratory experiments after 7, 15, 30 and 60 days were conducted including the mineralogical and microstructural examinations, grain size analysis, plasticity limits, unconfined compressive tests, vane shear tests and oedometer tests. The results indicate that soft clay soil of high organic content of 14% can be stabilized satisfactorily with the addition of 7% lime. The results also demonstrate that the changes in the mineralogical contents and soil fabric of high organic lime-treated soft clay improve soil plasticity, strength and compressibility
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