UNDRAINED SHEAR STRENGTH PARAMETERS OF SAPROCK FROM A WEATHERING PROFILE OVER PORPHYRITIC BIOTITE GRANITE AT KM 31 OF THE KUALA LUMPUR - KARAK HIGHWAY, PENINSULAR MALAYSIA

Three broad zones can be differentiated at the weathering profile; an upper, 9.4 m thick, pedological soil (zone I), an intermediate, 31.7 m thick, saprock (zone II) and the bottom bedrock (zone III). The saprock (zone II) comprises gravelly silty sands that distinctly preserve the minerals, textures and structures of the original granite and can be separated into sub-zones II A, II B, II C, and II D, based on differences in preservation of relict structures and content of litho-relicts (core-boulders). To characterize the undrained strength of saprock, samples were collected from sub-zones II A, II B, II C and II D and their physical and soil index properties determined before unconsolidated undrained triaxial tests were carried out on remolded samples. Three to four individual samples from each sub-zone were compressed under confining pressures of 138 kPa, 207 kPa, 276 kPa and/or 345 kPa. Plots of pf = [(σ1 + σ3)/2] versus qf = [(σ1 - σ3)/2] were then used to calculate apparent cohesions of 41.9 kPa, 100.3 kPa, 76.1 kPa and 73.9 kPa, and friction angles of 32.2o, 28.1o, 26.6o and 27.8o, for the samples from sub-zones II A, II B, II C, and II D, respectively. Regression analyses show apparent cohesions to decrease with increasing clay contents, and degrees of saturation; features indicating the influence of negative pore water (or suction) pressures. Regression analyses also show apparent friction angle to increase with increasing sand contents; a feature attributed to greater inter-locking and resistance to displacement of these particles. It is concluded that the undrained shear strength parameters of saprock are characterized by an average apparent cohesion of 54.6 kPa, and friction angle of 30.5o; the parameters influenced by the degree of saturation as well as clay and sand contents.

REVISITING THE FINANCIAL ISSUES AND THE IMPACT TO CONSTRUCTION PROJECTS IN MALAYSIA

Every activity in a construction project is related to time and cost. Delay is considered common and often occurred in a construction project. A slight delay can be very costly. It will impact all of the related stakeholders. This paper seeks to identify the financial issues in the construction industry and the impact of the financial issues towards the projects in Malaysia. Literature reviews and questionnaire surveys were used to carry out the study. The data collected were analysed via Microsoft Excel and SPSS software. The paper reveals that the withholding of payment by the approval parties is the critical financial issues in Malaysia’s construction industry, while the main impact when the financial issues occurs is where the project is delayed/postponed/terminated. The findings of this research will give a good insight to the industry and help to improve the local players’ competitive capabilities as highlighted by the Construction Industry Development Board (CIDB) in the Construction Transformation Programme (CITP) 2016-2020 and in line with the Sustainable Development Goals (SDGs) that was introduced by the United Nations (UN).

EFFECT OF PH2S INFLUENCE ON AUSTENITIC STAINLESS STEEL 316L CORROSION BEHAVIOURS IN CHLORIDE ENVIRONMENT / KESAN PENGARUH TEKANAN SEPARA GAS H2S TERHADAP TINGKAH LAKU KAKISAN KELULI TAHAN KARAT 316L DI PERSEKITARAN KLORIDA

H2S corrosion of equipment and pipeline system failures in oil and gas industry is a major concern of researchers as it involves high maintenance costs. Therefore, this study discusses the effect of H2S partial pressure at 0, 3 and 15 bar towards the corrosion behaviour of 316L austenitic stainless steel in chloride environments. The 316L steel exposed to 0 bar pH2S was slightly corroded due to the presence of Cr element which has increased the corrosion resistance of the 316L steel. However, pit penetration rate of 316L steel was increased by 90.1% from 0.07 mm/year at 0 bar pH2S to 0.74 mm/year at 3 bar pH2S and decreased by 83.2% at 15 bar pH2S due to the saturated sulfide content in the test solution. Therefore, 316L steel at 3 bar shows highest corrosion effect due to the dissolution of Cr element at 316L steels surface, thus enhanced passive film breakdown.

RESOURCE UTILIZATION ANALYSIS OF HIGHWAY PROJECTS USING ARENA

The construction sector is a significant contributor to the Gross Domestic Product of a developing country. Infrastructure improvement plays a vital role in this wherein highway construction is a dynamic sector requiring proper planning and scheduling multiple resources. Appropriate integration among various associated stakeholders is essential for a project’s success, aided by supply chain management. Resource planning is one of the basic concepts in supply chain management, with material and equipment management being the critical area. The main objective of this study is to develop a conceptual supply chain simulation model using ARENA, to analyze the equipment idling and utilization rate, keeping inter-arrival time for dispatch, the number of equipment, and working hours as constant. This model employs the real-time ‘best fit’ material utilization data as input. Material utilization data collected from 62 construction projects are analyzed to arrive at a ‘best fit’ probability distribution. This study’s conceptual supply chain simulation model helps formulate suitable material and equipment delivery plans to lessen risk in construction projects.

VARIATION IN BEARING CAPACITY OF SOIL DUE TO CHANGES IN WATER TABLE DEPTH IN DHAKA, BANGLADESH

The bearing capacity of the soil is a significant topic in geotechnical engineering, especially in foundation engineering, as the stability of any foundation depends on it. A structure with a very sound design may collapse standing on poor soil with low bearing capacity. As the depth of the water table increases, the ultimate bearing capacity of soil increases. The effect of an increase in depth on safe bearing capacity is predominant due to an increase in surcharge weight. The higher the water table, the lesser is as far as possible and strength of the soil. In this research, soil test reports of different locations of Dhaka city were collected, and the bearing capacity of the soil was calculated by Terzaghi's method based on a fixed foundation depth with a variation of water table depth. Bearing capacity was compared with the depth of the water table in graphical format and it was seen that bearing capacity of soil increases with the increase of water table depth.

EXAMING THE PRACTICE OF MANGEMENT ASPECTS AND MAINTENANCE IMPLEMENTATIONS OF WELFARE FACILITIES IN IRAQ’S CONSTRUCTION INDUSTRY

The Iraqi construction industry has many problems, especially when it comes in terms of coordinating and managing welfare facilities for the construction project. Proper managing and regular maintenance of welfare facilities is a task divided between official parties in charge of safety and health, mostly the contractors, clients, managers, and work-force. The need for safe work conditions that seem very much lacking in the Iraqi construction sites. This research examines how effectively management is mainly conducted within construction welfare facilities in Iraq’s construction industry. Using a quantitative methodology for collecting and analyzing data in consdreation of the listed objectives, A questionnaire survey was administered to experienced engineers (58) that are involved in the construction industry for investigating the keys causative in management and maintenance aspects. The data was analyzed and interprented using SPSS-12. Most of the analyzed results were classified as important and very important, but some awareness was missing related to planning and inspection. Finally, the interpretation illustrated that the awareness of management and maintenance of welfare facilities are in need to be more studied within the scope of worker’s productivity, health, and safety.

INCIDENCES OF BITUMEN CONTAMINATION OF WATER SOURCES IN SOME COMMUNITIES OF ONDO STATE, NIGERIA

Bitumen was discovered in some communities: Agbabu, Ilubinrin, Lodasa and Boridele in Ondo State, Nigeria around 1900 but was found inadequate for commercial exploitation. This report is on the levels of presence of bitumen in the areas and its effects on the available water sources and to make recommendations. Samples of water taken from 3 selected streams and 2 wells per location were subjected to physico-chemical analyses in line with America Public Health Association (APHA). Questionnaire were administered to sixty (60) people from bitumen-affected areas which covered sources of water, water pre-treatment measures, availability of water treatment facilities and effects of bitumen deposits on water bodies. Results obtained shown that most water users sourced water from groundwater recorded 73.33% followed by 16.67% for surface water and 9% for rain water harvesting. There might be population using a combination of the two or more sources of water. About 90% of the respondents knew that direct use of such water was harmful for drinking, washing, bathing and cooking. Water quality impairment such as colour and high level of salt are common in the water. This practice could have health implication on them if continued unabated. Pollution index for toxic metals (Pb,As and Hg ) and Total Petroleum Hydrocarbons(TPH) values determined were relatively high suggesting pollutant are related to the bitumen deposits in the region. For example Ilubinrin well (0.5 mg/L), and Lodasa well (0.3 mg/L) while others were at non detection level. For TPH, there were variations in the tested water samples, Lodasa well recorded the highest value of 1480 mg/L, Agbabu stream 900, Ilubinrin stream and well 240 mg/L and 120 mg/L, respectively, Agbabu well 110 mg/L, and the least at Lodasa stream 80 mg/L. This could be attributed to seasonal rain that control streamflow of water bodies in the bitumen-rich area. The study indicated that bitumen, being a complex mixture of hydrocarbons and associated metals was responsible to the pollution level in the water bodies reported

EFFECT OF FLY-ASH ON THE STRENGTH DEVELOPMENT OF COASTAL SOILS-A CASE STUDY FOR THE SOUTHERN COASTAL ZONE OF BANGLADESH

The rapid demand for urbanization expands the requirements of infrastructures and owing to the scarcity of available firm land; people are now built structures on soft soils. However, the application of a deep foundation for a low-rise structure may not be economically feasible for developing countries. The economic, as well as safe foundation, can be ensured by adopting traditional ground stability approaches. However, replacement of the industrial by-product, which possess minimum environmental threat may be a plausible option for ground stability. Therefore, an attempt is taken in this research to study the improvement of soft coastal soil by replacing with eco-friendly fly ash. The eastern bank of the river Karnaphuli, which has increasing industrial and residential demand is taken as a case study in this research. A series of experimental set-ups have been conducted to evaluate the strength development with different fly ash contents. It is found that the strength of fly ash treated soils increases with fly ash content up to a threshold value, and beyond that, the strength decreases. In addition, compaction and plasticity characteristics are also investigated through experimental observations and show better performance criteria with increasing fly ash contents. In a nutshell, this approach of replacing fly ash is suitable for coastal soil, and the experimental investigation reveals that an optimum 20% of fly ash content is justified.

CALIBRATION AND VALIDATION OF SWMM MODEL IN A SUB CATCHMENT IN ELDORET TOWN, KENYA

Flooding in Eldoret town has been occurring during heavy downpours resulting in loss of property, live and interruption of transportation systems. This study aimed at determining the catchment characteristics in Eldoret town for the calibration and validation of SWMM5 model. This model was developed by US Environmental Protection Agency. The model has been evolving from Version 1 in 1971 to Version 5 of 2005 called SWMM5. It can simulate runoff quantity in any given catchment. Rainfall was measured using rain gauge while discharge was measured using current meter. Digital Elevation Model of the study area was also obtained. The results showed that the catchment drained an area of approximately 696.5 hectares with a total of 23 sub catchments. The average slope was found to be 2.57% and the mean average imperviousness was 25.72%. The drain base flow was found to be 0.002 m3/s. However, during prolonged rainfall, the discharge increased up to 32.4 m3/s. The maximum rainfall observed during the study period was 32.4 mm which resulted in the maximum average discharge of 0.131m3/s and resulted in overflow in the drain. Calibrated model had N-Imperv of 0.45, Dstore-Imperv of 2.5 and Dstore-Perv of 8. ISE values of 1.9 and 1.4 were observed for calibration and validation, respectively. NSE values of 0.97 and 0.99 were observed for calibration and validation, respectively. This meant that model excellently simulated rainfall-discharge relationship in the study area and can be used for final design by the Eldoret town engineers. Future study is required to calibrate the model based on more measurements of rainfall and their discharges in the catchment.

ASSESSMENT OF THE BEST PROBABILITY DISTRIBUTION METHOD IN RAINFALL FREQUENCY ANALYSIS FOR A TROPICAL REGION

The Intensity-Duration-Frequency (IDF) curve defines the relationship between rainfall intensities at certain durations and with the frequencies. The IDF Curve is extensively used in many applications such as flood modelling and peak discharge estimation. Over the years, the frequent occurrence of flood has become a great challenge in Kelantan river basin. Herein, IDF curves using frequency analyses based on different distributions were developed and compared. The historical rainfall data at eight rainfall stations for the period of 1985-2019 were selected for the assessment purpose. The Gumbel, Normal and Log Pearson Type III distributions were fitted into the annual maximum rainfall series for durations varying from 30 minutes to 24 hours. The goodness of fit tests were then used to evaluate the performances of each frequency distribution. It was found that the Gumbel distribution gave the highest passing rate followed by the Log Pearson Type III and then the Normal distributions. The Gumbel distribution resulted in respective 86% and 75% passing rate since most of the p-values generated by both the K-S and the Mann-Whitney test were greater than 5% of significance level leading to the acceptance of the null hypothesis. Thus, the Gumbel distribution is suggested for the frequency analyses in this study.