Journal of Civil Engineering, Science and Technology

EDITORIAL: INTEGRATION OF HYDROLOGICAL MODELS AND MACHINE LEARNING TECHNIQUES FOR WATER RESOURCES MANAGEMENT

2025-03-07T10:05:29+08:00

Hydrology and water resources management ensure the sustainable use, conservation, and allocation of water in natural and engineered systems. Climate change, urbanization, and rising water demand necessitate advanced modeling approaches to enhance water security and resilience to extreme hydrological events. This editorial scope explores the integration of conventional hydrological models with machine learning to improve predictive accuracy, decision-making, and resource optimization. Physics-based models such as SWAT, VIC, and HEC-HMS simulate watershed processes, while hydraulic models like HEC-RAS and MIKE SHE assess flood risks. Groundwater models (e.g., MODFLOW) analyze aquifer dynamics, and optimization models support efficient reservoir and watershed management. Despite their reliability, these models require extensive calibration, high-resolution data, and struggle with capturing nonlinear hydrological complexities. Advancements in computational power and data availability enable machine learning to complement traditional models. Algorithms such as ANNs, SVMs, and RF enhance hydrological forecasting, while deep learning methods (LSTMs, CNNs) improve spatio-temporal predictions. Hybrid models integrating physical-based simulations with machine learning-driven corrections reduce uncertainties, enhance computational efficiency, and enable adaptive water management. Machine learning applications extend to flood forecasting, drought risk assessment, and climate change impact analysis, strengthening disaster mitigation efforts. Integrating AI with hydrological models offers promising advancements in real-time monitoring, infrastructure resilience, and water governance. However, challenges related to data availability, model interpretability, and computational complexity remain. Future research should focus on explainable AI, refined hybrid modeling, and machine learning-based decision-support systems. As AI, remote sensing, and big data evolve, their convergence with hydrological sciences will drive more intelligent and sustainable water management solutions.

UTILIZATION OF RECYCLED POLYETHYLENE TEREPHTHALATE (RECYCLED PET) FIBERS FOR INNOVATIVE CONCRETE PROPERTY ENHANCEMENT

2024-03-28T04:43:32+08:00

The construction industry's expansion, driven by larger and more intricate projects, has increased the demand for concrete across various sectors such as residential and infrastructure development, mirroring the ongoing trend of urbanization. To align with environmental concerns, the industry is now prioritizing eco-friendly construction methods. This study focuses on incorporating recycled Polyethylene Terephthalate (recycled PET) bottle fibers into conventional concrete. The goal is to vary the fiber percentage to achieve optimal compressive strength and desired workability, addressing the challenge of finding the right balance between these key factors. The PET fibers were irregularly cut and mixed with standard concrete materials, including cement, aggregates (fine and coarse), and water, with the addition of Plastocrete Plus as an admixture. The fiber size used was 25 mm long, with a width ranging between 1-2 mm, cut non-uniformly. The percentage of PET fibers was adjusted based on the weight of the cement to achieve enhanced strength and workability. The PET fibers at 0%, 2%, 4%, 6%, and 8% were tested for workability and compressive strength. Numerous specimens, including 15 cube specimens, were tested, and the optimal dosage of recycled PET fibers was determined. The results indicate that, after 21 days of curing, the 4% fiber content exhibited a significant increase in compressive strength, approximately 13.3%. The study validates the obtained optimum dosage by comparing it with relevant literature. Considering both the literature and the findings of this study, it is concluded that the practical application of PET bottle fibers in the construction industry is feasible.

DECADAL CLIMATE VARIABILITY AND CHANGE IN EDO STATE, NIGERIA

2024-05-17T01:22:29+08:00

This study examines the decadal variability of temperature and rainfall in Edo State, Nigeria. This is crucial for decision-making in various industries like infrastructure, water resources, agriculture, and energy. The study utilized gridded Climate Research data from 25 local communities between 1956 and 2016, cross-checked against Nigerian Meteorological Agency (NiMet) data, and applied various time series analysis methods. The results demonstrated that the state has experienced both abrupt and gradual increases in temperature, particularly during the decade spanning 1976–1985. The most probable time frame for a sudden temperature change was 1980. Changing by 0.14856 ⁰C on average per ten years, 1986–1995 was the coldest decade, and 1976–1985 was the hottest, with the typical temperature difference of -0.01723 ⁰C every ten years. Rainfall varied by an average of 61 mm/decade in the wettest decade (1986–1995) and 14.08 mm/decade in the driest (1976–1985). The spectral examination revealed that 15 years was the most significant frequency for both temperature and rainfall. The study found low rainfall and temperature variability of 9.66% and 1.315%, respectively. This study proposes strategies to mitigate and enhance adaptive capacity in response to the impacts of climate change, thereby raising awareness about its impact due to rainfall and temperature.

A REVIEW OF STRUCTURAL PERFORMANCE OF GEOCELLULAR PLASTIC MODULE

2024-04-30T01:18:32+08:00

The use of geocellular plastic modules, also known as stormwater modules, has begun to replace traditional drainage systems, which fail to sustain the unprecedented volume of stormwater runoff and convey floodwaters to the receiving watercourse in time. This subterranean module is a good and sustainable solution, because it can manage water sources through retention, infiltration, and attenuation. It is also suitable for the development of metropolitan areas with limited land. However, to date, the understanding of modules’ real short-term or long-term structural behavior is limited. This work attempted to summarize the structural behavior of geocellular modules under various boundary conditions. The current codes of practice on traffic loads were reviewed, and the design of this geocellular plastic module was discussed. In Malaysia, the Public Works Department or Jabatan Kerja Raya (JKR) standard is used for national traffic load applications, while ASSTHO is applied internationally. Traffic loads are the primary contributors to vertical loading, whereas backfill soil and water pressure represent potential lateral loads that could impact the stormwater module system. For future application recommendations, it is suggested to consider the vertical and lateral loads that are applied to the system, which are not specified in the current code of practice. This review provides a higher confidence level when applied to the current construction industry.

TRAFFIC MANAGEMENT AND ENGINEERING IMPACT ON TWO ADJACENT SIGNALIZED INTERSECTIONS - A CASE STUDY IN PONTIANAK

2024-05-17T01:20:40+08:00

The prevalence of closely situated intersections in Pontianak City presents unique challenges, notably evident at signalized intersections along KH. Ahmad Dahlan Street. A short-term strategy for mitigating this issue involves leveraging traffic management and engineering techniques to optimize traffic flow informed by on-site evaluations. Through direct surveys conducted at both intersections, data were gathered to assess the current conditions, serving as a basis for designing a new cycle time while considering coordination theory. Using the MKJI approach, calculations were performed to optimize the performance at each intersection, with green-time adjustments facilitating coordination between them. Analysis of the existing performance revealed a saturation degree (DS) of 0.86 for the four-way intersection and 0.68 for the three-way intersection, slightly deviating from the MKJI requirement of DS = 0.75, signaling discomfort, and safety concerns. Notably, a queue length (QL) exceeding 200 m and delay time (DQ) surpassing the 25-second green cycle time underscored the necessity for improvements. Consequently, a new cycle time plan was devised, with a determined 95-second cycle time, 36-second offset time, and 16-second bandwidth adjustments between directions. The implementation of this new cycle time yielded improved intersection performance, as evidenced by the decreased average delay and queue length for both intersections. This case study investigates the efficacy of traffic management and engineering strategies at adjacent signalized intersections in Pontianak with the aim of analyzing their impact on alleviating congestion and enhancing traffic flow in urban settings. Employing various data collection methods, including traffic volume counts, intersection observations, and commuter surveys, this study demonstrates that optimizing signals, managing lanes, and enhancing pedestrian facilities significantly enhance traffic efficiency and safety. These findings offer invaluable insights for urban planners and policymakers by guiding the development of effective traffic management solutions to address congestion challenges in similar urban contexts.

EFFECT OF SUPERPLASTICIZER ON MECHANICAL PERFORMANCE OF CONCRETE MADE WITH CIGARETTE BUTTS

2024-04-07T21:24:02+08:00

Cigarette butts are among the most extensively littered wastes in the world. About 1.3 billion smokers worldwide produce trillions of cigarette butts every year. Discarded cigarette butts leach toxic chemicals and heavy metals into the environment, polluting water and soil. The aim of this research is to confine cigarette butts within concrete to eliminate its hazardous effects on the environment. However, the inclusion of cigarette butts in concrete may lead to poor mechanical properties and durability. A high-range water-reducing admixture (superplasticizer) has been used in concrete to compensate for the strength and durability loss. Cylindrical concrete specimens containing different percentages of cigarette butts (0%, 10%, 20%, and 30%) by weight of cement were prepared with and without a superplasticizer. The prepared specimens were tested to assess the mechanical performance of the concrete. It was observed that 10% inclusion of cigarette butts may be performed without significantly compromising the mechanical performance, and superplasticizer may be added to concrete to slightly enhance the mechanical properties.

EFFECT OF PRETEST DRYING AND TESTING PROCEDURE ON ENGINEERING PROPERTIES OF BAHIR DAR RESIDUAL SOILS

2024-08-29T14:35:15+08:00

Residual soils are natural weathering products of rocks and their properties depend on the degree of weathering. These types of soils, which are found in tropical areas, are commonly used in construction, such as dams, highways, and building materials. The properties of residual soils are influenced by a variety of factors, including the original material, climate, topography, drainage, and the methods used for sampling, testing, and classification. Inadequate soil investigations can lead to inaccurate test results, which may result in flawed designs, project delays, increased construction costs, the need for post-construction repairs, and even construction failures. The engineering properties of residual soils are significantly affected by the drying process and testing procedures. This study evaluated the index properties and chemical composition of Bahir Dar residual soils to assess their suitability for various geotechnical engineering applications. The research found that the engineering properties of these soils were significantly affected by the pretest drying and testing procedures. The study recommends soaking the soil samples in water instead of drying and breaking them down with a rubber mallet, as the current standards allow. Additionally, it was observed that the specific gravity values of the residual soils change not only based on the soil texture and particle size distribution, but also on the drying methods used.

REVOLUTIONIZING SUSTAINABLE CONSTRUCTION THROUGH RECYCLED CONCRETE AGGREGATE PRODUCTION: A SYSTEMIC REVIEW OF CODES, STANDARDS AND GUIDELINES

2024-05-17T09:53:04+08:00

The significant rise in the production of construction and demolition (C&D) waste has increased dramatically in recent years, resulting in the entry of tons of concrete waste into the environment. Recycling and reusing C&D waste as a partial replacement for aggregate in building construction is practiced in other nations as a possible solution and waste management. However, few studies have identified how C&D waste can be utilized in the Ethiopian Construction Industry (ECI). In addition, the application of recycled concrete aggregate (RCA) in Ethiopia is limited owing to a lack of well-established standards and guidelines. Thus, the focus of this research is to investigate the opportunities and limitations of recycled concrete building materials based on legal design codes, standards, and government guidelines for utilizing recycled concrete waste as aggregates. This study systematically reviewed existing norms and standards for the potential use of recycled concrete aggregates and identified opportunities and limitations by incorporating them into current design and construction practices. This study evaluates the current state and utilization practices of RCA in economically comparable developing countries, drawing comparisons with Ethiopia. The findings revealed inconsistencies in the national standards concerning the permissible substitution of natural aggregates with recycled alternatives. Furthermore, the existing standards lack crucial parameters, such as the precise influence of the source concrete grade on the recycled material properties and the impact of service life on its characteristics. To address these shortcomings, it is essential to develop local design codes, laws, and standards, specifically for RCA in developing countries. Such measures will bolster stakeholder confidence in the sector’s applicability, utilization, commercialization, and promotion of this sustainable material. This study is expected to contribute to the standardization of recycled concrete in Ethiopia and similar developing countries where such guidelines or standards do not exist.

PERFORMANCE OF SUSTAINABLE CONSTRUCTION PROJECTS: A CONTRACTOR’S VIEWPOINT

2024-09-09T12:52:01+08:00

Achieving stakeholder satisfaction and attaining the objectives are considered indicators of success in construction projects. Performance criteria may consist of one or more indicators influenced by project's stakeholders and characteristics. This study uses an exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) to determine the key indicators affecting project performance from the contractors’ viewpoint. A set of 120 structured quantitative questionnaires survey were distributed to actively registered G7 contractor companies in Pulau Pinang. Ten hypothesized factors consisting of 42 indicators were measured using a five-point Likert scale and subsequently analyzed using SPSS software. Results of EFA showed eight re-evaluating affected factors of construction project performance in Pulau Pinang; most notably, factors such as Labor, equipment, consultant, and contract (LCC) which consists of fifteen indicators, giving factors loading of 0.495 to 0.804, Eigenvalues (20.5), and variance (48.9%). Based on stakeholders’ perspective, CFA identified four statistically significant project performance factors: LCC, People, Time, and Project characteristic with factor loading and covariance values > 0.7 and < 0.8, respectively. By pinpointing these factors and validating them via a dual-phase statistical approach, this study provides actionable insights for enhancing performance in sustainable construction projects, offering practical value to stakeholders and contractors in similar contexts, particularly during difficult situation in project delivery.

COMPARATIVE STRENGTH ANALYSIS OF CONCRETE USING HIGH ALUMINA CEMENT AND PORTLAND LIMESTONE CEMENT

2024-09-09T12:33:55+08:00

This study investigates and compares the strength characteristics of concrete incorporating High Alumina Cement (HAC) and Portland Limestone Cement (PLC). Both chemical and physical tests were performed on HAC and PLC, along with additional physical tests to assess aggregate properties. Preliminary testing was conducted in accordance with relevant standards, yielding satisfactory results. Slump tests indicated that the workability of both HAC and PLC concretes fell within the S1 classification. A comprehensive evaluation of compressive, split tensile, and flexural strength was conducted on concrete specimens cured for 3, 7, 14, 21, 28, and 56 days. The results demonstrated that HAC concrete significantly outperformed PLC concrete, with average strength increases of 38% in compressive strength, 15% in split tensile strength, and 21% in flexural strength. Additionally, HAC concrete exhibited 4% lower water permeability than PLC concrete, indicating greater durability. These findings suggest that HAC is a superior option for structural applications requiring rapid strength gain and reduced permeability. Therefore, HAC is recommended for construction applications requiring early load-bearing capacity and improved durability.