bluuebunny/crossref_metadata_2025 huggingface dataset:
LATE PAYMENT PRACTICES IN THE MALAYSIAN CONSTRUCTION INDUSTRY
Authors: Mohd Badroldin Mohd Khairul Anas , Abdul Hamid Abdul Rahim , Abdul Raman Syazwani , Zakaria Rozana , Mohandes Saeed Reza
Published: December 2024

Factors that influence contractors â€žcash flow are the frequency of payment, delay, profit margin, retention fund, payment term to the supplier and subcontractor, advanced payment and others. Late payment from the client has become a habit in the construction industry and this practice had caused many implications such as bankruptcy, the higher contract sum due to higher risk, uncomfortable relationship between the payer and payee, disturbance of supply chain and others. The aim of this paper is to examine the late payment practices in the Malaysian construction industry. Thirty seven (37) sets of questionnaire had been collected among the Grade G7 contractors and subcontractors in the state of Selangor based on convenience sampling. The collected data were analysed by using frequency distribution and relative important index (RII). The Data then was tabulated and illustrated in the form of charts. The results of the study show that the late payment is one of the most critical problems in the Malaysian construction industry. The majority of the contractor experienced late payment quite frequently and even beyond the stipulated contract term. The top three impacts of the late payment problems are the negative chain effect on other parties, delay in project completion and lead to bankruptcy or liquidation
A NUMERICAL AND ANALYTICAL STUDY ON OPTIMIZATION AND EFFICIENCY OF STRUCTURAL FORMS BY TWO-OUTRIGGER IN TALL BUILDINGS
Authors: Marabi Bahram , Marsono Abdul Kadir
Published: December 2024

The selection of a suitable structural system and resist lateral loads in tall buildings plays an important role in structural design. The increase of the heights in the high-rise buildings will be limited because of exceed drift due to lateral loads. The outrigger systems always have been the best choice to limit the lateral deflections in slender buildings. This paper presents analytical and numerical methods to determine optimum location of the outriggers through the height of the building. Optimization and efficiency of the outriggered structural systems were examined in the reduction of the top drift. In the analytical method was used an idealized model as Two- Dimensional (2D) due to horizontal loads. In this regard, Three-Dimensional (3D) building frames were simulated as numerical method by Abaqus/CAE program. Two types conventional forms of the outrigger systems were considered as lateral resisting systems. The numerical models were utilized two outriggers as forms of (a) and (b). Pushover analysis was conducted under uniformly lateral load that was distributed throughout the height. The obtained results by the 2D analytical method shows that the model of the form (a) was optimized when the second outrigger located at 0.58H from the top of the structure while the first outrigger was fixed at the top, in the form (b) was optimized where the outrigger levels were placed at 0.31H and 0.69H, from the top of the building. The results of the 3D modelling by Finite Element Analysis (FEA) indicated that in the form (a) in which the first outrigger is fixed at the top and the second outrigger is optimized at 0.55H from the top of the model. In this way, two outrigger levels of the form (b) were optimized at 0.29H and 0.62H from the top of the structure. The efficiency of the optimized two forms of the outrigger systems in the reduction of the lateral drift at the top of the building by numerical modelling were determined; the efficiency of the outriggers system form (b) is 42% higher than optimized model of the form (a). The 3D Finite Element Analysis (FEA) method for use in the initial design of an outrigger structural system in tall buildings is recommended because of reliable results in compared to the 2D theoretical analysis in order to an optimum design of tall buildings structure.
A LABORATORY STUDY OF VIBRATION EFFECT FOR DEFORMABLE DOUBLE-POROSITY SOIL WITH DIFFERENT MOISTURE CONTENT
Authors: Kok Foong Loke , Abd Rahman Norhan , Ramli Mohd Zamri
Published: December 2024

Earthquake vibration is a natural disaster that needs to be addressed in ensuring the geo-environment is sustainably secure. A physical laboratory model was conducted to characterize the phenomena of vibrated deformable double-porosity under different moisture content. The double-porosity soil characteristic is formed by aggregating kaolin soil with 32% and 33% moisture content. A vibrating table and seismic accelerometer were installed on soil sample in order to vibrate the whole acrylic soil column to get the peak table acceleration and peak specimen surface acceleration of the soil sample. The results show that the acceleration response analysis for the sample with 32% moisture content has caused sample dis-amplification shaking, while the sample with 33% moisture content has caused the sample amplification shaking and re-compact process to occur due to strong vibration. It was recorded that both vibrated samples have soil structure rearrangement and multi-porosity characteristics identified as problematic double-porosity soil expected to contribute to the speed of liquid penetration. In addition, the microscope result shows both samples have crumbs with diameter less than 0.5cm, which is considered to have granular soil structure.Thus, both samples displayed the characters of soil liquidity as the moisture content for both samples is close to kaolin soil liquid limit at 41%, and granules started to disintegrate at the moisture content of 34%.
ESTIMATING DISSOLVED OXYGEN DEPLETION IN INNER WESTERN JOHOR STRAIT, MALAYSIA USING A THREE DIMENSIONAL WATER QUALITY MODEL
Authors: Ismail Maznah , Hashim Noor Baharim , Kazemi Ziba
Published: December 2024

Characterization of changes in inner Western Johor Strait (WJS) of monitoring works was successfully carried out. Eight water quality data sets collected in this area from Second Link to Causeway Link. An extensive dissolved oxygen (DO) data set was used to develop a statistically meaningful way of estimating mean DO from discrete measurements in inner WJS. Relationships among bottom water DO, vertical stratification, and the factors responsible for stratification-destratification in this narrow stretch of water along the WJS with some recent continuous monitoring data. Therefore, it is imperative that the environmental of reclamation and dredging works, municipal or industrial discharge, marine aquaculture and shipping activities in this area be effectively controlled and managed. The purpose of this study was to assess the water quality condition in the Inner Western Johor Strait and the estimating the spatial variable ties of the mean salinity, temperature and dissolved oxygen conditions in WJS. An application of the three dimensional water quality model Environmental Fluid Dynamic Code (EFDC) was developed for the inner WJS to investigate the DO depletion along the strait and surrounding areas. The twenty-one state variable water quality model available in EFDC included multiple dissolved and particulate organic carbon constituents, as well as organic and inorganic nutrients, DO, and three phytoplankton constituents
MONITORING LABORATORY SCALE RIVER CHANNEL PROFILE CHANGES USING DIGITAL CLOSE RANGE PHOTOGRAMMETRY TECHNIQUE
Authors: Norizan Faezal , Abd Rashid Mohd Fadhli , Roslan Nurul Liyana , Sa'ari Radzuan , Ibrahim Zulkiflee , Mustaffar Mushairry , Hezmi Muhammad Azril
Published: December 2024

Measuring and monitoring of river channel evolution or changes under laboratory conditions is an important scope in hydraulic assessment. Measurement such as changes in river channel profile for instance, provides an important indicator on erosion and accretion rates in hydraulic modelling. Under controlled conditions, the changes in channel profile are usually measured using a high precision point gauge. However, when large numbers of points of river profile need to be measured, the use of point gauge method becomes laborious and time consuming. This study proposed a digital close range photogrammetry technique to measure natural river channel bed profile changes in laboratory. The objective of this study was to investigate the changes of physical river model profile for pre and post flooding simulations using digital close range photogrammetry technique. Small scale physical model experimental works were conducted in the Hydraulics and Hydrology Laboratory to observe the river profile evolution during the events. The flood flume utilized in this study is 4.95 m long, 1.38 m wide and 1.26 m deep with carved V-shaped natural main channel with a bed slope of 1:500. Data measured from digital close range photogrammetry technique during pre-flooding at t = 0 second and post flooding events at t= 9660 second were compared to determine the channel profile evolution or changes after simulation of flood event. The results show the changes in invert level or bed level between non-flooding and flooding events due to erosion is varies from 1 mm (minimum) to 6 mm (maximum) along the channel between chainage 0mm and chainage 2000 mm with total volume of erosion is 1157 x 103 mm3 respectively. It can be concluded that the digital close range photogrammetry technique can be used as a complimentary method to measure and monitor the changes of river channel profile in the laboratory
MECHANICAL PROPERTIES OF PALM KERNEL SHELL CONCRETE IN COMPARISON WITH PERIWINKLE SHELL CONCRETE
Authors: G. Eziefula Uchechi , E. Opara Hyginus , U. Anya Collins
Published: December 2024

Comparative analysis of mechanical properties of palm kernel shell concrete with periwinkle shell concrete is presented in the paper. The binder and fine aggregate were Ordinary Portland cement and river sand, respectively, while potable water was used for mixing and curing. The constituent materials were batched by weight. Concrete mix ratio was 1:2:4 and water/cement ratio was 0.5. Three groups of concrete mixes containing different coarse aggregates were tested: 100% palm kernel shells, 100% periwinkle shells, and 100% granite as control. Tests were carried out for bulk density and compressive strength of the concrete cubes at 7, 14, 21, and 28 days curing, respectively. The results revealed that for all curing ages, palm kernel shell concrete had lower bulk density and lower compressive strength than periwinkle shell concrete. The bulk density and compressive strength of the 28-day palm kernel shell concrete were 1840 kg/m3 and 14.02 N/mm2, respectively, those of periwinkle shell concrete were 1936 kg/m3 and 16.90 N/mm2, while those of granite concrete were 2496 kg/m3 and 25.95 N/mm2, respectively. Both palm kernel shell concrete and periwinkle shell concrete satisfied the bulk density and compressive strength requirements for lightweight aggregate concrete.
CONCRETE IN CHLORIDE ENVIRONMENT: COMPARISON OF RAPID ELECTROCHEMICAL TEST METHODS
Authors: Ahmed Syed Jamal Uddin , Das Tanmoy
Published: December 2024

This study investigates chloride durability of concrete prepared with Portland cement and binary additions consisting pozzolanic (Fly ash) and latent hydraulic (Ground Granulated Blast furnace Slag - GGBS) mixes and also with limestone powder. Specimens were subjected to electro-chemical rapid chloride migration tests of two different kinds, namely, Potential Difference (PD) and Multi-Regime (MR) tests. Both the tests measure chloride durability in terms of D, the Coefficient of Chloride Diffusion. The PD and MR test results show that in the early ages, 100% Portland cement concrete performed well against chloride diffusion. However, fly ash and GGBS concrete showed higher resistance against chloride migration at later stage. At equal strength grade, w/c ratio and age, GGBS concrete had the highest resistance against chloride among other cement types.
CRITICAL FACTORS AFFECTING QUALITY IN PUBLIC CONSTRUCTION PROJECTS IN BORNO STATE
Authors: Usman Gaji Abubakar , Mohamad Zin Rosli
Published: December 2024

Quality in construction projects both in the past and in present has assumed critical importance due to frequent cases of failure. Quality in public construction projects in Nigeria is on the decline greatly due to underachievement in the construction management process. The aim of this study is to identify factors affecting quality in public construction projects in Borno state. In achieving the objective of the study, a questionnaire survey was conducted involving a sample size of 70 respondents, which include architects, engineers, quantity surveyors, and contractors. The importance index of each factor was calculated for all the professionals. Percentage rank agreement factor (PRAF) was used to measure agreement of the importance ranking among the professionals. The results show the most critical factors affecting quality in public construction projects in Borno state are; â€˜lack of management commitmentâ€™, â€˜poor teamwork among project participantsâ€™, â€˜poor supervision by contractorâ€™, â€˜design changes and â€˜poor training systemâ€™. Respond of the professionalsâ€™ perspective on factors affecting construction quality in public projects in Borno state is the very first important step in initiating methods and processes for improvement of quality in public construction projects in Borno state.
CHARACTERISTICS OF VEHICLE HEADWAY DURING RAINFALL AT NIGHT IN PONTIAN, JOHOR
Authors: Hassan Sitti Asmah , Xuan Teoh Hao , Mashros Nordiana
Published: December 2024

The headway pattern of a traffic stream has a significant impact on the accident possibility of the road section. The aim of this study is to determine the impact of different rainfall intensities have on the headway pattern in Pekan Nenas, Pontian, Johor. In this study, the automatic traffic count system (ATC) is utilised to obtain vehicle headway on the site. Rainfall data were obtained from the Department of Drainage and Irrigation, Pontian. The rainfall data was categorised into three rainfall intensity categories which are light rain, moderate rain and heavy rain. The traffic data and rainfall data then were then embedded to analyse the headway pattern of road user on the road section during rainfall at night. The results from the analysis showed that the headway pattern at night time followed the gamma distribution model. It was found that the mean vehicle headway increases as the rainfall intensity increases.
MACROSCOPIC MODELING OF THE IMPACTS OF THE STANDARD GAUGE RAILWAY LINE ON THE PERFORMANCE OF THE NORTHERN ROAD TRANSPORT CORRIDOR
Authors: Meshack Ochieng , Mbeche Oyuko , Francis Gichaga
Published: December 2024

With a predicted rapid international and regional trade within the region, the Northern road transport corridor will have to deal with the challenges associated with additional traffic growth without compromising on travel time, safety and environmental concerns. Towards this, the Kenyan government embarked on the construction of the Standard Gauge Railway Line (SGRL) in order to improve the Northern Corridor network performance so as to enhance the logistics competitiveness along the corridor. The paper presents the findings of an ongoing research into the impacts of freight traffic on roadway capacity related elements such as travel time, speed, volume to capacity ratios as well as ozone emissions on the corridor. Under the plausible economic growth regime, the SGRL will only divert a maximum of 20% of freight demand from the road network and is expected to reduce capacity on the network, reduce travel time, minimize emissions concentrations and improve the entire network reliability. However, this will depend on the rail modal split capacity, and as such the excess capacity will only be handled by the road network which in turn will result into capacity constraints beyond the 2025. Further, the SGRL will result in substantial reduction of Ozone concentration along the network up to the forecast year 2020 only, beyond which the Ozone concentration on some sections of the corridor will begin to exceed the acceptable WHO standards of 100Î¼g/m3.
LEVEL OF AWARENESS ON LEAN THINKING CONCEPT IN CONSTRUCTION AMONG HIGHER LEARNING STUDENTS IN MALAYSIA
Authors: Tabatabaee Sanaz , Mahdiyar Amir , Yahya Khairulzan , Marsono Abdul Kadir , Sadeghifam Aidin Nobahar
Published: December 2024

Lean construction has been implemented throughout the construction industry in order to increase the profit by minimising non-value adding activities. Lean is a technique that manages the construction process to eliminate wastes, reduce costs, and deliver projects on time by breaking the construction projects to smaller parts of activities. Previous studies found that the most critical barriers to implementing lean construction approach in Malaysia are lack of knowledge on the lean concept and lack of commitment from management. The aim of this study is to investigate the potential barriers in implementing lean thinking within the construction industry in the future in Malaysia. In order to implement lean thinking in construction activities, involved parties should understand the lean principles, lean construction techniques and causes of waste. As a result, postgraduate students from the faculty of civil engineering and built environment were evaluated regarding their knowledge on lean construction and management commitment. The data were collected through a questionnaire survey distributed to 140 postgraduate students who involved in the construction industry afterwards. The results showed that construction management students are familiar with the concept of lean thinking. However, there is a need to enhance the knowledge of students from the faculty of civil engineering and built an environment of UTM in terms of lean thinking concepts. In terms of management commitment, the construction management students are entirely aware of their responsibilities in implementing lean construction.
PAVEMENT DESIGN FOR THIN BITUMINOUS LAYER AND GREENHOUSE GAS BENEFIT
Authors: Bagui Swapan Kumar , Das Atasi , Das Tanmoy , Saxena Anukul
Published: December 2024

Bituminous layer thickness is determined based on fatigue life and granular layer thickness is determined based on rut life. Higher bituminous thickness is required for increasing the fatigue life in pavement design thus increasing the project cost as well. In order to reduce project cost in some cases and places, fatigue life is not considered and pavement is allowed to design for rut life only and minimum bituminous layer is provided for protecting granular layer to avoid early distress. It depends on country practices and local experience. Cement treated sub base with granular base may be provided with thin bituminous surfacing of 40 - 90 mm to economize the project cost. This paper presents the development of Pavement design chart for thin surfacing and compare with conventional thickness and cost for few hypothetical case studies. Carbon credit is also compared for both cases. It is found from the case study that thin surfacing entails 20 % less cost and 28 % reduction of greenhouse gas (GHS) emissions compared to conventional pavement design.
DISTRIBUTED FIBRE OPTIC AS SENSOR FOR CORROSION DETECTION IN STEEL REINFORCEMENT
Authors: Wai Lew Shong , Ismail Mohammad
Published: December 2024

Previous studies indicated that problems with the application of distributed fibre optic sensor remain unresolved despite considerable effort in the last few decades. This research describes the work conducted to develop the use of BOTDA, as a distributed strain sensing technology, to identify the presence of corrosion in steel reinforcement in concrete structures. BOTDA is capable of measuring relative strain at any point along a standard optical cable. A properly installed cable can replace multiple closely-spaced strain sensing gauges and is considered cost-effective in this context. In corrosion monitoring, the presence of corrosion can be monitored by many means such as fibre optic sensing technique. The application of distributed fibre optic in corrosion detection seems to be a potential for research. The location of corrosion in steel reinforcement in concrete is expected to be detected from the occurrence of spike in the relative strain profile obtained from a single optical fibre. There are many implementations that require careful consideration and hence are examined in this research. Specimens were casted and installed with standard fibre optic cables along the steel reinforcement. Reinforcement were grinded at predetermined locations to reduce its cross sectional area to simulate cavity due to corrosion. Relative strain profiles were obtained from BOTDA when the specimens are loaded. Further investigation is recommended to make better sense of the results obtained
ANALYSIS OF BALLASTLESS RAILWAY TRACK STRUCTURES OVER SOFT CLAYS
Authors: Aly Mohamed Ismail , El-Shabrawy Mohamed , El Gendy Mohamed , Adel Turk Ahmed
Published: December 2024

Railway developments in Egypt have gained much interest recently. This development was in many fields one of which is railway speeds and the term high speed trains â€œHSTâ€ was introduced as an alternative on Egyptian national railways. HST has many challenges from a geodynamic perspective; such as the case of HST operating in areas with soft soils such as soft clays in Delta area in Egypt. In this paper, the problem of HST over soft soils was considered from a dynamic response point of view and ballastless tracks was investigated and compared with the traditional ballasted track. A track concept was introduced recently as a solution for this problem called â€œDeck trackâ€ but very few literature studied this idea. This track concept was studied and further modified into two other types. These tracks were dynamically analyzed using 3D finite element modeling constructed. Results of the ballastless track models will be compared with the Ballasted track model in order to observe if it mitigates the effects of HST over soft clays or not and also to show if the modified tracks is performing better than the Deck track or not. Dynamic response results of the models were displayed and comparisons were made for all track structures.
STATISTICAL ANALYSIS OF PHYSICO-CHEMICAL PARAMETERS AT KAINJI HYDROPOWER RESERVOIR, NIGERIA
Authors: Mohammed Abdulrasaq Apalando , Sule Bolaji Fatai , Salami Adebayo Wahab
Published: December 2024

The study evaluated physico-chemical parameters of Kainji lake, Nigeria. Water samples were collected from three sampling stations at Kainji hydropower reservoir from July, 2013 to April, 2014. Water samples were analysed for various physico-chemical parameters using various HACH equipment. Results of the physico-chemical analysis were subjected to simple trend plot and statistical analyses descriptive using Microsoft Excel and analysis of variance (ANOVA) test in Statistical Package for Social Science (SPSS) version 16.0 to determine if there are significant difference between water quality parameters measured at upstream and downstream ends of the reservoir at 0.05 level of significance. Results of the simple trend revealed that all the parameters varied with time at upstream and downstream ends. Results also revealed that there were significant differences in the water quality parameters such as hardness, sulphate (SO42-), copper (Cu2+), nitrite (NO2-), nitrate (NO3-), manganese (Mn2+) and resistivity while parameters such as water temperature, pH, salinity, suspended solids (SS), chloride (Cl-), iron (Fe2+), chromium (Cr3+), electrical conductivity (EC), phosphate (PO43-), silicon oxide (SiO2), total dissolved solid (TDS), turbidity and dissolved oxygen (DO) were not significantly different at 0.05 level of significant at upstream and downstream locations. Comparison between the measure parameters with the Nigeria and WHO water quality standards revealed that all the parameters are within the limit permissible by the standards except NO3- concentration. High concentration of nutrients such as NO3- and PO43- may be caused by socio-economic activities of people living around the lake. In conclusion, Kainji dam hydropower reservoir operation does not have any negative significant effect on the water quality at the station.
REVIEW OF DOWNSCALING METHODS FOR CLIMATE CHANGE IMPACTS ON WATER RESOURCES
Authors: Ahmad Nor Adilah , Zakaria Nur Ain , Mohammad Fathilah Nur Nabilah Farhana , Jeevaragagam Ponselvi
Published: December 2024

Measuring the impact of climate change on water resources is commonly based on downscaled simulations from global climate models (GCMs). The downscaling of GCMs is used to improve representation of climate data over a regional part which can be produced either by using a regional climate model (RCM) or statistical downscaling. Although both of these two techniques are common, but they are seldom compared. This study review the relationship between climate change and water resources, impact of climate change on hydrological system, and the discussion on several downscaling methods that are commonly used in the assessment of climate change impacts on water resources. Past studies have shown that climate change will directly affect water resources, and will result to increase or decrease of the water body on earth surface. This study found that statistical downscaling technique is more favourable and more efficient technique to assess the climate change impacts on water resources. However, it is still not clear which methods can give the most reliable estimates of projected climate change, since the modelling procedures of GCMs have their own strengths and limitations.
NUMERICAL INVESTIGATION OF FILLET WELDS EFFECTS ON THE LOCAL BUCKLING OF BOX STEEL COLUMNS
Authors: Hashemi Seyed Shaker , Hemmat Mehdi , Sadeghi Kabir , Vaghefi Mohammad , Masihzadeh Amin
Published: December 2024

The local buckling has always been known as an undesirable and destructive phenomenon in steelstructures. Thus, it is necessary to identify the effective factors in local buckling of the steel box column. Currently, box columns are generally fabricated by welding plates using fillet or groove welds with various manufacturing patterns, in terms of weld leg size and the overlap length of the plates. Hence, the evaluation of these patterns and also the control of local buckling in built sections seem to be essential. In this research, a variety of columns with different welding patterns, including groove and fillet welds with various overlap values and weld legs are numerically modeled and their local buckling behavior is studied in the finite element domain by using ABAQUS software. A suitable welding pattern is proposed by assessing the energy absorption, as well as stress distribution, stress concentration and finally local buckling in steel box section columns. The obtained results indicate that, the sections fabricated utilizing groove welds, have the best nonlinear performance. And also a suitable implementation of fillet welds to fabricate steel box columns is to consider 20% overlap length and 80% weld leg size to plate thickness as this model subject to small amount of local buckling. This model has shown less than 6% reduction in plastic capacity and energy absorption in comparison with groove welding. Another method is to use 50% for both overlap length and weld leg size to plate thickness. This model has shown less than 8% reduction in plastic capacity and energy absorption in comparison with groove welding. In addition, unsuitable implementation of fillet welds especially with small overlaps and weld leg sizes has shown a 12.5% reduction in plastic capacity and energy absorption, compared to groove welding
VARIATION OF PAVEMENT DESIGN WITH ENVIRONMENTAL TEMPERATURE VARIATION
Authors: Bagui Swapan Kumar , Das Atasi , Verma Kaushlendra Kumar , Bagui Soumadeep
Published: December 2024

Indian Roads Congress (IRC): 37-2012 is the main guideline for design of flexible pavement. This guideline developed several pavement design charts ready for use based on Average Annual Pavement Temperature (AAPT) which varies from 200 C to 400 C. Environmental condition pertaining to the monthly variation of temperatures have not been considered in the pavement design. This paper presents pavement design considering variation of resilient / elastic modulus value at different time periods throughout the year (month wise) using Indian Institute of Technology(IIT) Pave software and compare conventional pavement design as proposed in IRC: 37 â€“ 2012. A different temperature model has been used to determine pavement temperature month wise. Different resilient moduli (E) values of Bituminous Concrete (BC) and Dense Bituminous Macadam (DBM) have been considered based on air temperatures and design life based on monthly pavement temperature is calculated for each month and average value is adopted for final pavement design life. It has been found that conventional pavement design is underestimated when pavement design is conducted using monthly variation of pavement temperature at design tire pressure of 0.56Ã— 106 N/m2 and below and is overestimated at higher tire pressure. Design life with variation of temperature is found 3 times approximately obtained from conventional method of pavement design. It is also found that rut and fatigue life varies with tire pressure.
STRENGTH PROPERTIES OF 10 MILLIMETERS TIMBER CLINKER AGGREGATE CONCRETE
Authors: Jung Chai Teck , Sidek Ahmad B. , Kiong Chow Tio , Noor N.M.
Published: December 2024

This paper presents some experimental results and discusses the used of timber clinker as partial aggregate replacement in producing concrete. A number of tests were conducted to identify the physical properties of timber clinker aggregate such as density, aggregate impact value (AIV) test and aggregate crushing value (ACV) test, slump, X-Ray Fluorescence (XRF) test and compressive strength of timber clinker aggregate concrete. Two series of concrete mixes with Supracoat SP1000(C0, C10, C20, C30) and without Supracoat SP1000(CA0, CA10, CA20, CA30) with various percentage of 0%, 10%, 20% and 30% 10 mm sieve size timber clinker aggregate used as partial replacement in producing concrete. A total of forty 150 x 150 x 150 mm cubes samples were prepared for both series of concrete mixes and tested at 7, 14 and 28 days of water curing. The results obtained showed that timber clinker aggregate concrete gained highest compressive strength for both series of concrete mixes C20 and CA20 which was 37 MPa and 34 MPa respectively. The optimum percentage used of timber clinker aggregate in producing concrete was 20% where if exceeded will decreased the compressive strength and Supracoat SP1000 added tend to improve the concrete slump. The physical properties test indicated the contribution to the concrete strength development. The results obtained and observation made in this study suggest that timber clinker aggregate successfully used as partial replacement in producing concrete and performed better strength development
CORROSION BEHAVIOR OF REINFORCING STEEL IN RC SLAB CONTAINING CHLORIDES WITH PARTIAL REPLACEMENT OF CEMENT AS FLY ASH
Authors: Gupta Sristi Das , Sugiyama Takafumi , Islam Md Shafiqul
Published: December 2024

Steel reinforcement in concrete containing fly ash has been practically employed to RC structures in snowy cold region and coastal areas so that the durability of the structures against corrosion can be enhanced. In this research to make the compatibility with RC slab bridge sodium chloride solution of 10[WU1]Â % in concentration was applied on RC slab and corrosion development was monitored by electrochemical method. Applying fly ash in RC slab at two replacement levels of 15[WU2]Â % (F15) and 30% (F30) of cement the specimens were observed. The observation result verified that fly ash concrete showed longer period of corrosion initiation (ASTM C876) than normal reinforced concrete. The initiation period of corrosion was 4.5 and 6 times longer for F15 and F30 concrete than normal concrete, as well as 91 days strength of F30 concrete was about 14% higher that of norma concrete. Test result showed that fly ash has better influence on steel corrosion reduction than concrete cover increment. It was observed that fly ash concrete (F15 and F30) with 3 cm concrete cover has better corrosion resistivity than using 4 cm cover of non-fly ash concrete. Furthermore, using the same concrete cover (3 cm) it was found that the actual corrosion rate was decreased about 68 to 82% by adding fly ash 15 to 30% respectively compared to normal reinforced concrete. In addition, a significant attenuation in corrosion area in rebar between fly ash concrete and normal concrete was found. Based on actual corrosion area on rebar surface, actual corrosion current density was larger than corrosion current density found from non-destructive way. Moreover, further analysis was conducted for characterization of different corrosion products using Raman spectroscopy with 532 nm wave length. It revealed that the corrosion product (Oxides and Oxyhydroxides compound) were less in F15 and F30 concrete compared to normal concrete. Considering these results, the possibility of reduction of chloride induced corrosion in reinforced concrete structure using fly ash has confirmed.Â
STRENGTH CHARACTERIZATION AND GRADING OF LESS-USED NIGERIAN GROWN TIMBER SPECIES FOR STRUCTURAL APPLICATIONS
Authors: R.O. Rahmon, , A.A. Jimoh,
Published: December 2024

The demand for timber is unlimited as it continues to increase rapidly in Nigeria. There is problem of undocumented properties of unpopular timber species used locally, especially in developing countries such as Nigeria. This research therefore aimed at characterizing and grading of three (3) less-used timber species in Nigeria for structural uses. Ayunre (Albizia zygia), Eku (Brachystegia eurycoma) and Ire (Funtunia elastica) timber species were obtained from different sawmills in Ilorin, Nigeria and preparation of various test specimens are in accordance with British Standards BS 373: 1957. A total of 300 specimens were used in determining the strength characteristics of the timber species a 300 kN capacity Testometric Universal Testing Machine (UTM) at Agricultural and Biosystems Engineering Laboratory, University of Ilorin. Twenty (20) specimens for each timber species were tested for structural/strength properties according to the British Standard. Results show that the timber species had average moisture contents of 12.47, 11.78 and 12.71% for Ayunre, Eku and Ire, respectively. For density classification, Ayunre and Eku were classified as heavy wood and Ire as light wood. The results obtained provided quantitative details of the strength properties of selected timber species which can be used in determining the application of these timber species for structural applications. The timber species were, therefore graded according to NCP 2 (1973), EN 338 (2009) and BS 5268 (2002).
REPAIR OF FLEXURAL DAMAGED REINFORCED CONCRETE BEAMS USING EMBEDDED BAMBOO REINFORCED EPOXY COMPOSITE
Authors: Odeyemi Samson Olalekan , Abdulwahab Rasheed , Bello Sefiu Adekunle , Omoniyi Ahmed Olatunbosun , Adeniyi Adewale George
Published: December 2024

In recent years, repair and retrofit of existing structures such as buildings and bridges have been among the most important challenges in Civil Engineering. Strengthening reinforced concrete (RC) members with steel plates is a conventional method that has been adopted for decades. The corrosive nature of steel plates, its weight and the need for many anchor bolts for attachment makes it inefficient for retrofitting damaged structures. Thus, there is a need to source for an alternative material which does not corrode and still be used in the strengthening of reinforced concrete. Bamboo Reinforced Epoxy Composite (BREC) was used to repair five (5) damaged reinforced concrete beams in this research. Two of the beams were preloaded to 40 % and 60 % of the ultimate load before strengthening with BREC and all the beams were loaded to failure. The RC beams implanted with BREC rods experienced a rise in their load carrying capacity when tested. Beams preloaded up to 40 % and 60 % had an increase in flexural strength of 33.7 % and 39.3 % respectively when compared with beams reinforced with steel reinforcements. BREC rods in concrete is an effective method in increasing the flexural strength of RC beams.
TREATMENT METHODS FOR BITUMEN POLLUTED WATER(BPW) - A REVIEW
Authors: Atojunere Eganoosi Esme
Published: December 2024

This review is set to answer the question about current and alternative treatment methods available for treating Bitumen000. 12021Polluted Water (BPW). Bitumen is a complex form of hydrocarbon with a higher viscosity than crude oil preventing it from flowing under natural conditions. BPW is formed due to bitumen seepage from underground reservoirs causing contamination of land and waterbodies in areas where the deposit is untapped. Another wastewater from bitumen is the Bitumen Wastewater (BWW) which is formed from bitumen extraction and processing, though this review centered on bitumen-polluted water BPW, studies revealed that BWW exhibits similar characteristics of floatable solids, high levels of salt and taste, colour, hardness of water, high Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) levels, toxic metals: lead, cadmium and dissolved petroleum hydrocarbons: Benzene, Toluene, Ethylbenzene, Xylene (BTEX). It has been reported that these pollutants were recalcitrant, persistent in biodegradation, and required many years to denature. This review summarized treatment methods for bitumen polluted water and by extension BWW from five aspects, which contain flotation, filtration, coagulation, biological treatment, and combined technology. Further, it addressed modifying the existing Bitumen Polluted Water Treatment System (BPWTS) with the possibility of scaling it up to treat more volume of BPW to meet water treatment demand in the bitumen-rich areas.
FEASIBILITY STUDY OF A FIXED OFFSHORE OTEC PLANT FOR COST-EFFECTIVE POWER GENERATION IN MALAYSIA
Authors: Abu Husain Mohd Khairi , Mohd Zaki Noor Irza , Azman Nurul Uyun , Sarip Shamsul , Jaafar A Bakar , Mukhlas Nurul ‘Azizah , Ahmad Shah Mohamad Shazwan , Umar Sarehati , Ng Chiew Teng , Yahaya Nordin , Mat Soom Ezanizam , Syed Ahmad Sayyid Zainal Abidin
Published: December 2024

Ocean Thermal Energy Conversion (OTEC) is a renewable energy technology that harnesses the temperature differential between warm surface water and cold deep ocean water to generate electricity and freshwater. Technological advancements have made OTEC increasingly viable, positioning it as a potential solution for sustainable energy generation in Malaysia. Despite its promise, OTEC development in Malaysia is challenged by the need for suitable sites and the high capital costs associated with traditional floating OTEC platforms. Additionally, efforts to attract anchor partners for OTEC projects have been met with limited success, slowing progress in implementation. This study assessed the feasibility of OTEC plant development in Malaysia through the analysis of sea temperature profiles, identifying five potential sites. A multi-criteria analysis was conducted considering factors such as cold water intake pipe length, proximity to power transmission lines, and environmental impact. The study also proposes a fixed offshore OTEC platform with a single-legged caisson structure, incorporating a braced substructure and dual-level production decks to optimize space for equipment and reduce CAPEX. Kuala Baram (Location C) was identified as the most favorable site due to its optimal conditions for cold water intake and proximity to transmission infrastructure. The proposed fixed platform design offers significant CAPEX reductions compared to floating alternatives, enhancing OTEC’s economic potential. The study’s findings support the immediate application of OTEC in Malaysia, particularly in ongoing projects off the coast of Sabah. Further research, including modeling and testing of the platform design, is necessary to advance commercialization and establish OTEC as a key component of Malaysia's renewable energy strategy.
EFFECT OF INCORPORATING RAM-FAT AND OIL INTO THE BITUMEN GRADE 60/70
Authors: Attahiru Yusuf Babangida , Mohamed Azman , A. H. Norhidayah , Umar Kabiru Dangoma , Sanda Bashir Yahaya , Ibrahim Abubakar , Allami Jabir
Published: December 2024

The ability of a pavement to resist fatigue cracking, rutting, and thermal cracking is mostly dependent on bitumen, which assists in minimizing the occurrence of pavement distress. The objective of the study is to determine the optimum ram fat and oil (RFO) content suitable for the application of bituminous mixtures. Saturated fats and oils consumption in excess can boost blood levels and may lead to bad low-density lipoproteins cholesterol, which raises the danger of heart failure and stroke. To minimize this problem, this study encourages the incorporation of RFO into bitumen to reduce the consumption of fats and oils in our society. The characteristics of the standard and RFO-modified binders were evaluated by penetration, softening point, and ductility tests. The RFO content (1.0%, 2.0%, 3.0%, 4.0%, and 5.0% by mass of the bitumen) was blended with the bitumen for 35 minutes with a mixing speed of 1000 rpm. The result of the optimum RFO content was discovered at 3.0% which improved the performance of the mixture. It was found that bitumen grade 60/70 documented a significant improvement with the addition of RFO content. The optimum RFO content can be raised with a smaller bitumen grade.
EXPLORING THE USE OF PALM KERNEL SHELL AND PALM FIBRE AS SUSTAINABLE AGGREGATES IN CONCRETE
Authors: Seng Ng Hock , Teng Ng Chiew , Bature Abdullahi Muktar , Abu Husain Mohd Khairi , Mohd Zaki Noor Irza , Ahmad Shah Mohamad Shazwan , Umar Sarehati , Mukhlas Nurul ‘Azizah
Published: December 2024

Palm kernel shells and palm fibres are leftover materials from the palm oil industry. However, they are not fully utilized and encounter disposal issues, particularly in Malaysia where they are produced in large quantities. This research aims to enhance sustainability and reduce palm waste disposal in Malaysia by exploring the potential of substituting palm waste for conventional aggregates. Six experiments were carried out to assess both the physical properties (including density, UPV, and water absorption) and mechanical properties (such as compressive strength, flexural tensile strength, and splitting tensile strength). The results indicate that a 35% palm kernel shell substitution is optimal, and it was able to produce a concrete specimen of 18 MPa cube strength, approximately 40% lower than the control specimen's 30 MPa. Despite this reduction, the strength is adequate for structures such as driveways, footings, and footpaths. The flexural and splitting tensile strength were the highest, at 4.99 MPa and 2.36 MPa, respectively. This batch also exhibited the best physical properties with a density of 2149 kg/m3, UPV of 3828 km/s, and water absorption of 9.31%. Additionally, the research also concludes that the addition of palm fibre in concrete tends to increase tensile strength by about 6%.
EXPERIMENTAL STUDY OF CONCRETE AS PARTIAL REPLACEMENT OF COARSE AGGREGATE BY SILICA SLAG
Authors: Mubashshira Labiba , Reza Prium , Khan Abu Sayem , Rahman Md. Mahmudur
Published: December 2024

Aggregate is a key component of concrete, greatly impacting its volume and influencing its mechanical strength, durability, and serviceability. This study examines using silica slag, an industrial by-product waste, as a partial replacement for coarse aggregate (Recycled Brick Chips) in concrete. It assesses concrete properties with silica slag replacing recycled brick chips at 0%, 20%, 40%, and 60%. The findings show that adding silica slag with recycled brick chips enhances both compressive and tensile strengths. Concrete mixes, prepared with superplasticizer (ASTM C-494: Type A & F), achieved improved workability while maintaining the required water-cement ratio. Various mechanical properties of silica slag, such as impact resistance, specific gravity, unit weight, void ratio, and water absorption, were thoroughly tested. The study reveals that a 40% replacement of coarse aggregate with silica slag results in optimal compressive strength, around 18 MPa. This indicates that concrete incorporating recycled brick chips and silica slag can achieve moderate compressive strength and meet structural requirements effectively to achieve sustainable development.
DEVELOPMENT OF A COMPUTER PROGRAMME FOR THE DESIGN OF MUNICIPAL WASTEWATER TREATMENT FACILITIES Part 1: The Incoming .Conduit and Screening Facility
Authors: Demun Amat Sairln
Published: December 2024

A computer programme was developed using Fortran?? utilizing ffiM-PC compatible microcomputers to design the incoming conduit and screening facility in municipal-wastewater treatment plant. The prograIIl!Ile calculates the dimensions and capacity of the facilities and determines the hydraulic flow profile of each of the facility. The programme runs successfully given the input data which is the total number of population served, the incoming conduit diameter and Manning's n. The results are easy to interpret and appeared automatically on an output file.
PRESTRESS LOSS OF POST-TENSiONED CLAY DIAPHRAGM AND FIN BRICKWORK
Authors: Tapsir SHi Hamisab
Published: December 2024

Unlike calcium silicate and concrete block masonry which undergo shrinkage with time, clay brickwork has been known to expand instead. Expansion of brick units in prestressed masonry will cause an increase in the prestressing force instead of prestress loss. However, not all clay brickwork expand with time; higher strength clay units tend to undergo shrinkage with time. The main objective of this paper is to present experimental data obtained for prestress loss in post-tensioned high strength clay diaphragm and fin brickwork. The main objective of this paper is to present experimental data obtained for prestress loss in posttensioned high strength clay diaphragm and fin brickwork. The brickwork were built from clmis B clay engineering brick with compressive strength of 103 MPa with designation (ii) mortar. The tests which involve monitoring prestress loss, creep and shrinkage of clay sections were carried out over a period of 120 days. Usiog the 120-day experimental data, the predicted long-term prestress loss is 20%
SHORT-TERM SALINITY PREDICTIONS IN BACK BAY OF BILOXI, MISSISSIPPI
Authors: Hashim Noor Bahadm
Published: December 2024

In the development of a water quality model for Back Bay of Biloxi, the Water Quality Analysis Sirnulation-5 (WASPS) was used. The model is calibrated to a set of field data acquired on Back Bay of Biloxi, during June 14 - 16, 1977 and is verified with another set of field data taken in the Bay, during July 28 - August 2, 1972. The transport mechanisms of the estuary are modeled in each of the 376 segments of two-dimensional vertically mixed system by simulating salinity as a conservative tracer. Comparisons of the predicted and observed salinity data are made qualitatively by using spatial and temporal comparisons ,and quantitatively by statistical comparisons. The response of model prediction calculations is consistent with trends of the observed salinity data ranges, but not with absolute values in all cases. The results indicate that the model can accurately predict the concentration of salinity in the range of observed data taken at low and high tide conditions.