Journal of Structural Monitoring and Built Environment
Journal of Structural Monitoring and Built Environment (JSMBE) is a peer-reviewed journal that is scheduled for biannual publish. The JSMBE covering broad scope areas of structural engineering, structural monitoring and assessment, and built environment which is divided into 16 subject areas. JSMBE is supported by national and international editorial board consisting of a distinguished team of researchers. This journal aims at high quality research while maintaining rigorous peer-review process. JSMBE will also occasionally publish review articles and bring out special issues on a specific sub-field of structural engineering, structural monitoring and assessment, and built environment. Authors are encouraged to contact the Journal's Editors for the submission of review articles or special issues of the Journal. We welcome contributions from local and international researchers and practitioners in various field of structural engineering, structural monitoring and built environment.
Effectiveness Of Repair Material Using Polypropylene Fiber
The study investigated the impact of polypropylene fiber on the properties of SikaGrout®-215 mortar, focusing on compressive and flexural strength. Tests were conducted on mortar samples with a characteristic strength of 65-70 N/mm2 at 28 days. Polypropylene fiber volume fractions of 0.1%, 0.3%, and 0.5% were examined, with a control mix having no fiber. Surprisingly, fiber addition had no positive effect on compressive strength but significantly increased flexural strength. The addition of fiber increased pore structure, permeability, and porosity, although these decreased with longer curing periods. Despite falling within the range of good quality, the optimal mixture design was observed with a 0.3% fiber combination.
Polypropylene , SikaGrout®-215 , mortar repair , compressive strength, flexural strength.
Copyright (c) 2026 Journal of Structural Monitoring and Built Environment https://creativecommons.org/licenses/by-nc-sa/4.0
Design and Tensile Performance of Face-to-Face Flange Connections of Cold-Formed Steel C-Section
Cold-formed steel (CFS) is widely used in structural applications due to its high strength-to-weight ratio and material efficiency. However, the performance of its connections is often governed by localized resistance mechanisms. This study investigates the behaviour of face-to-face flange (FTFF) sleeve connections in CFS C-sections, with particular emphasis on bearing and shear resistances. Analytical design resistances were determined in accordance with Eurocode 3 (EC3), and experimental validation was conducted through laboratory testing of 9 specimens with varying plate thicknesses (0.75 mm and 1.00 mm), sleeve lap lengths of 200 mm, and screw quantities (4 and 6). Tensile test of the several types of connection styles was performed using a 120-ton universal testing machine. From the experimental results, it shows increases in material thickness and screw quantity primarily enhance connection performance through improved bearing resistance and load transfer efficiency. The ultimate tensile load (Pu) ranged from 15.20 kN to 29.21 kN. The calculated normalization ratios, defined as the ratio of the experimental load Pu to the design bearing resistance, exceeded unity and ranged from 1.27 to 1.67. This confirms that bearing deformation governed the failure mechanism. In contrast, the shear resistance ratios remained below unity, within a relatively narrow range of 0.54 to 0.85, indicating a significant margin, which is also influenced by variations in thickness and screw configurations. The failure modes were dominated by bearing deformation with hole elongation and localized plate yielding, accompanied by minor screw tilting, with no screw fracture observed. Finally, optimal FTFF connection performance can be achieved through a balanced design that enhances bearing and shear resistances by appropriately configuring material thickness and fastener number to improve connection capacity.
Role of Nano Materials in Improving Compressive Strength of Bio-Foamed Concrete Bricks: Towards Green Concrete Production
This study explores the enhancement of compressive strength in bio-foamed concrete through the integration of nanomaterials such as nano rice husk ash (NRHA), nano eggshell powder (NESP), nano coffee grounds (NUCG) as cement replacements, alongside the bacterial agent. By utilizing agricultural and food waste, this research aims to investigate the compressive strength of bio-foamed concrete brick (B-FCB) at 28 days using screening stage method. The nano materials enhanced the compressive strength of the B-FCB. The optimal replacement materials for the maximum compressive strength were 1% NRHA, 1% NUCG, and 5% NESP, combined with Bacillus tequilensis at a concentration of 3×105 cells/ml. The empirical modelling indicated that Bacillus tequilensis and ESP have a significant effect on the compressive strength of B-FCB. Incorporating nanosized agro-industrial wastes into B-FCB improves mechanical performance while reducing the environmental impact of accumulated wastes.
Behaviour Of Cold-Formed Steel Built-Up Square Battened Columns Composed of Different Spacing of Chord and Battened Plate
This study investigates square hollow sections (SHS) in built-up cold-formed steel (CFS) battened columns, aiming to assess structural performance and the impact of varied spacing configurations between chords and battened plates. Four configurations were tested under axial compression to evaluate differences in load-carrying capacity, deformation, and buckling behavior. Experimental results revealed that specimens with narrower chord and batten spacing exhibited higher stiffness and load capacity, while wider spacing led to earlier onset of buckling and greater lateral displacement. Notably, the configuration with 50 mm chords and 300 mm batten spacing achieved the highest ultimate load of approximately 590 kN, demonstrating superior axial performance. Load-strain and lateral displacement patterns confirmed that reduced spacing enhanced stability and delayed buckling failure. These findings provide actionable insights into optimizing the design of CFS battened columns for enhanced structural efficiency and reliability in engineering applications.
Copyright (c) 2025 Journal of Structural Monitoring and Built Environment https://creativecommons.org/licenses/by-nc-sa/4.0
Bond Strength of Self-Sensing Concrete (SSC) Incorporating Biomass Activated Carbon
Self-sensing concrete (SSC) has emerged as a multifunctional smart material that combines structural performance with self-monitoring capabilities, offering significant potential for structural health monitoring. In this study, biomass-activated carbon (BAC) was incorporated into SSC as a supplementary cementitious material to investigate its impact on bond strength. While BAC is known to enhance electrical resistivity and compressive strength, its effect on interfacial bonding behaviour has not been comprehensively evaluated. Therefore, this study aims to assess the bond strength of SSC incorporating BAC (SSC-BAC). The mix design of SSC-BAC is based on C25/30, which consists of ordinary Portland cement (OPC), silica fume, BAC, sand, and water. Cube specimens were prepared for the compression test. Meanwhile, rectangular and prism specimens were prepared for the slant shear and three-point bending tests. Experimental tests revealed that the compressive strength decreases as BAC content increases. A similar trend was also observed in the bond strength. The threshold for the compressive strength is 31.54 MPa produced by 1% BAC. Meanwhile, 3% BAC has the lowest acceptable bond strength. The findings of this study suggest that SSC-BAC exhibits a strong bonding behaviour, which is suitable for application in structural health monitoring.
Finite Element Modelling on The Tensile Performances of Boxed-Flange Cold-Formed Steel C- Section Connections
Cold-formed steel (CFS) has gained significant attention due to its high strength-to-weight ratio, cost-effectiveness, and ease of fabrication. This study focuses on finite element modeling (FEM) of boxed-flange connections in CFS C-sections under tensile loading, using WELSIM software to simulate structural behavior. The research validates FEM results against experimental data, performs a parametric study on steel thickness and number of screws, and compares failure modes to optimize connection design. The findings indicate that increasing steel thickness and screws enhances load-bearing capacity and delays failure onset. The FEM model predicted a yield load of 24.23 kN for 1.00 mm thick connections with 4 screws, closely matching the experimental result of 23.50 kN. For 0.75 mm thick connections with 2 screws, the FEM model predicted 6.87 kN, compared to the experimental 7.00 kN. These results validate the efficiency of numerical modeling for structural optimization.
Cold-formed steel, finite element modeling, tensile performance, boxed-flange connection, WELSIM simulation
Heritage Building Maintenance Practices: The Case of Muzium Diraja Kedah (MDK)
Maintaining heritage buildings requires a well-structured maintenance management system to ensure their continued usability and cultural significance. The Muzium Diraja (MDK) in Alor Setar, Kedah, an important historical landmark, faces several maintenance-related challenges, including financial constraints, limited access to original building materials, and a constrained maintenance budget, which affect the effectiveness of ongoing maintenance activities. This study investigates the current maintenance practices adopted at the museum using a qualitative case study methodology. Information was obtained through in-depth interviews with seven key personnel selected through purposive sampling, representing conservation, development, monument-related agencies, and the Public Works Department (JKR). The analysis identifies critical weaknesses in several key aspects of maintenance management, including organizational structure, asset management, maintenance strategies, workforce capabilities, financial provision, and documentation practices. Based on these findings, the study proposes targeted improvement measures, including the adoption of a structured maintenance management system, the implementation of proactive and planned maintenance strategies, the enhancement of technical skills among maintenance personnel, sufficient financial allocation, and systematic record-keeping. These measures are intended to support the sustainable preservation of the Muzium Diraja Kedah and safeguard its heritage value for future generations.
How Heat Waves Influence Project Performance in the Construction Industry?
Heat waves in Southeast Asia are becoming increasingly common and intense, posing substantial challenges for the construction industry. As the heat waves are predicted to increase in the future, they will certainly impact construction project performance, specifically in terms of cost, time, and quality. This paper aimed to analyze the impact of heat waves on these project performances. A questionnaire survey using Microsoft Forms was used to gather the data. This paper focuses on 200 respondents from Grade 6 (G6) and Grade 7 (G7) contractors in Johor Bahru, Johor. The findings show the interrelated effects on time, cost, and quality. The productivity of workers decreased as they required a longer time to rest, which led to delay issues. Additionally, exposure of the material to heat and workers' focus on work influence the poor quality of the project. The heat forcing in additional safety measures and heat-related illnesses necessitate more labor, further escalating project costs. Therefore, the paper concludes that heat waves influence construction in Malaysia through an increased duration cost and risk of project completion associated with quality.
Prediction of Damage Severity in Steel Bridges Using Natural Frequency Data and Artificial Neural Networks
Steel bridges are essential to transportation systems and must be regularly inspected to guarantee their robustness and safety. Conventional methods of identifying damage are subjective and time-consuming, frequently depending on manual inspections. This study aims to overcome these limitations by using Artificial Neural Networks (ANNs), which are sensitive to changes in mass and stiffness caused by damage, to predict the severity of damage in steel bridges based on natural frequency data. This research proposes a new method for detecting damage in steel girder bridges by integrating natural frequency data with ANNs. This vibration-based fault detection method addresses the shortcomings of traditional approaches by employing natural frequency as a dependable indicator of structural irregularities. An ANN model was trained and validated using an extensive dataset that included natural frequency data from experimental modal analyses conducted under various damage conditions. To assess the model's accuracy in predicting the severity of damage, its performance was studied on a different dataset. The findings indicate that ANNs can effectively analyze frequency data to accurately predict the severity of damage, reducing the reliance on manual inspections. In addition to improving the effectiveness of structural health monitoring systems, this strategy supports the robustness and safety of steel bridge infrastructure. Overall, the findings demonstrate that ANNs trained using modal curvature data provide a reliable and effective solution for early damage detection in steel girder bridges, substantially improving safety and operational performance. This novel approach advances the field of structural health monitoring and offers a valuable means of preserving the integrity of critical infrastructure, including steel girder bridge systems.
The Role of Adaptive Reuse in Revitalizing Abandoned Buildings in Malaysia
In the context of urban development constraints, adaptive reuse of abandoned buildings in Malaysia presents a promising opportunity. While abandoned buildings contribute to significant economic and environmental challenges, they also hold considerable potential for revitalization through adaptive reuse projects. This study explored the key factors influencing the adaptive reuse of buildings and the challenges encountered in such initiatives. The primary aim was to examine the role of adaptive reuse in revitalizing abandoned buildings in Malaysia. Employing a Delphi study approach, data was collected from industry professionals through a questionnaire survey, which identified the factors and challenges associated with adaptive reuse projects. The study revealed several key consideration factors, including government incentives, originality, actors in decision-making, environmental and architectural merit, and social interest. Additionally, it highlighted critical challenges, such as maintenance issues, building code compliance, constraints in building performance, complications arising from multiple ownership, and uncertainties regarding renovation processes. The findings provide valuable insights and recommendations for policymakers, developers, and urban planners, advocating for a sustainable urban development model that leverages adaptive reuse to enhance economic resilience and environmental preservation in Malaysia. The study's limitations include a narrow focus on the Malaysian context and the reliance on expert opinions, which may not fully capture the perspectives of all stakeholders. Future research could address these limitations by broadening the scope to include more diverse perspectives and exploring additional case studies in different regions.
Labour Productivity for External Works Construction: Case Study in Kluang, Johor
The construction industry in Malaysia faces persistent productivity challenges, including a shortage of skilled labor, high worker turnover, and equipment inefficiencies, which lead to project delays, reduced output, and compromised quality. Accurate labor productivity data is critical for optimizing workforce allocation, scheduling, and resource utilization; however, the lack of such data hinders effective decision-making. This study evaluates labor productivity in external infrastructure projects, focusing on roadworks, drainage systems, and sewerage systems in Kluang, Johor. Using direct measurement methods, productivity rates across various tasks were assessed, and the impacts of factors such as site conditions, weather disruptions, and workforce experience were analyzed. The findings highlight the positive influence of skilled labor and appropriate equipment on productivity, while adverse weather and site-specific challenges were identified as significant contributors to inefficiencies. Effective site management was found to be a key determinant of improved labor productivity and adherence to project timelines. Recommendations include workforce training, enhanced site management practices, and optimized labor allocation to mitigate delays, improve productivity, and deliver competitive project outcomes.
Exploring The Impact of Depression Among C&S Engineer at Construction Industry
This study investigates the prevalence, contributing factors, and impact of depression among civil and structural (C&S) engineers within Sarawak’s construction industry. Depression, a critical mental health concern, is closely associated with diminished workplace safety performance, productivity, and overall well-being. Data were collected from 220 respondents through structured surveys, incorporating instruments such as the Cornell Musculoskeletal Discomfort Questionnaire (CMDQ) and Likert-scale assessments. The data were analyzed using descriptive statistics, correlation analysis, and regression techniques. The results indicate that multitasking demands, tight project deadlines, and physical fatigue are major contributors to depression, which was primarily reported at mild to moderate levels. Regression analysis revealed a strong relationship between depression and safety performance, with depression accounting for 95.9% of the observed variability. Additionally, symptoms like mental fatigue and musculoskeletal discomfort compound workplace challenges. These findings underscore the urgent need for targeted mental health support, ergonomic interventions, and policy reforms to enhance both employee well-being and safety outcomes in the construction sector.
Investigating The Role of Sustainable Practices in Construction Materials Handling: A Pathway Towards SDG Integration
This research explores the integration of sustainable practices in construction materials handling to enhance sustainability and support the achievement of Sustainable Development Goals (SDGs). The study aims to identify current barriers in construction materials handling practices to pinpoint inefficiencies and areas ripe for improvement in sustainability, determine the potential benefits of implementing sustainable practices in construction materials handling on the achievement of Sustainable Development Goals (SDGs) and propose strategies for integrating sustainable practices into construction materials handling processes effectively.. Using quantitative data collection and analysis, the study reveals that sustainable materials handling practices lead to cost savings (mean = 4.06) and that insufficient regulatory support is a major barrier (mean = 4.0). Enhanced reputation (mean = 4.15) and prioritizing green building certifications (mean = 4.19) are highlighted as key benefits and strategies, respectively. Reliability analysis shows Cronbach's Alpha values between 0.835 to 0.916, indicating good to excellent reliability, with an overall value of 0.888. These findings emphasize the need to address regulatory barriers and focus on green certifications to foster sustainable practices in construction materials handling, aligning the industry with SDGs.
Sustainable practices, Construction Materials Handling, Sustainable Development Goals, Construction industry
Investigation of Circular Construction Waste Management (CCWM) Practices in Malaysia
This research investigates the adoption of Circular Construction Waste Management (CCWM) practices in Malaysia, focusing on the environmental and economic challenges posed by construction waste. The study aims to identify key challenges, determine effective waste management practices, and propose sustainable solutions to enhance resource efficiency. A quantitative survey was conducted with data analyzed using SPSS for reliability and descriptive insights involving 130 construction personnel such as those engineers, project managers, main contractors, construction manager, site consisting of workers, and supervisors. The findings reveal that the high cost of recycled materials mean value 4.85 are the most critical barriers to adopting circular economy principles. Among the recommended practices, the "3R" approach Reduce, Reuse, Recycle emerged as the highly effective practice with the highest mean value of 4.89. By adopting these practices, stakeholders can reduce environmental impacts, improve resource efficiency, and achieve a more sustainable construction industry.
Energy Absorption Study of Concrete Incorporating Spent Garnet Subjected to Low-Velocity Impact Loads
Several researchers examine the concept of mitigating the impact during collisions between vehicles and concrete barriers, such as enhancing the energy absorption capacity of the barriers. As a result of this matter, this issue demands the use of sand, potentially resulting in the exploitation of natural resources. Hence, this study was utilizing waste material such as spent garnet (SG) as a partial fine aggregate replacement under low-velocity impact loads in order to predict the energy absorption produced from concrete containing SG. SG was used as a partial fine aggregate replacement using 0%, 10%, 20% and 30% of SG percentage. This study experimentally examines the compressive strength of sample which yielded at 43.5 MPa, 41.3 MPa, 42.1 MPa and 40.7 MPa for SG0, SG20, SG30 and SG40 respectively. The optimum percentage was chosen, and the block specimens were prepared for low-velocity impact test. All 12 block specimens were tested under a low-velocity impact test with fix velocity at 2.43 m/s. The results reveal that SG20 indicates ideal crater since the crater diameter almost same as diameter for nose hemispherical projectile used in this study which is 40 mm. The penetration depth for block specimens are 1.74 mm, 1.79 mm, 1.76 mm and 1.84 mm for SG0, SG20, SG30 and SG40 respectively. Thus, the results in penetration depth shows by the increment of SG content in the concrete mix produce higher penetration depth. In term of energy absorption, the result was directly proportional to penetration depth which the higher penetration depth produces higher energy absorption. Thus, the 20% SG mixture demonstrated the most promising result between compressive strength and energy absorption. This indicates that incorporating 20% SG into concrete barriers has significant potential for improving their performance, making them more effective in mitigating the impact of vehicle collisions and reducing the risk of fatalities.
Application of Artificial Neural Networks to Identify Earthquake-Induced Structural Damage in Residential Buildings
Structural damage in residential buildings can significantly compromise the safety of occupants, reduce the structural integrity of the building, and shorten its overall lifespan, potentially leading to costly repairs, decreased property value, and increased risk during natural disasters such as earthquakes or storms. Traditional methods for assessing structural damage primarily depend on manual inspections, which are not only time-consuming and labor-intensive but also susceptible to human error, subjectivity, and inconsistency. These limitations can lead to delayed detection of critical issues, inaccurate assessments, and increased risk of overlooking hidden or early-stage damage, ultimately compromising the effectiveness of maintenance and safety measures. By employing a comprehensive dataset that includes a range of structural characteristics and damage indicators, this study trains a neural network model to identify and learn patterns linked to structural damage. This study investigates earthquake-induced damage in different structural components of residential buildings, employing hundreds of feature sets including building height, number of floors, earthquake intensity, damping ratio, crack location, and material properties to train and validate a network for damage prediction. The performance of the ANN is evaluated, demonstrating superior accuracy and efficiency. The results highlight the potential of ANNs to revolutionize structural health monitoring by providing rapid, cost-effective, and reliable damage assessments, thereby enhancing preventative maintenance and mitigating risks associated with structural failures.
An Investigation into Strength Prediction of Columns Strengthened with CFRP Using Artificial Neural Networks
This study presents an investigation into the strength prediction of columns strengthened with Carbon Fiber Reinforced Polymer (CFRP) using Artificial Neural Networks (ANNs). The research aims to develop a reliable predictive model for estimating the ultimate load-carrying capacity of CFRP-strengthened columns by considering key influencing parameters. A dataset comprising numerical results was used to train and validate the ANN model. The selected input parameters included column length, column diameter, steel tube thickness, concrete compressive strength, steel yield strength, CFRP ultimate tensile strength, CFRP thickness, and the number of CFRP layers. The ultimate axial strength served as the output parameter. The developed ANN model demonstrated high accuracy in predicting the column strength, capturing the nonlinear relationships among the variables effectively. The results confirm that artificial neural networks can serve as a powerful tool for structural strength prediction, reducing the need for extensive experimental testing and offering valuable insights for engineering design and assessment.
A Study on The Current Practices of Safety and Health by Contractor in The Construction Industry at Sarawak
The Occupational Safety and Health (Amendment) Act 2022 expanded the scope of Malaysia's Occupational Safety and Health Act 1994 to include all workplaces, emphasizing stricter safety regulations and penalties. Despite this, the construction sector, particularly in rapidly urbanizing Sarawak, remains high-risk, significantly contributing to occupational fatalities. This study aims to assess current safety and health practices among contractors in Sarawak's construction industry and propose improvements. Focusing on Sri Aman, Sibu, and Bintulu, data were collected through questionnaires and observations, analyzing management, social, and risk control aspects. Findings reveal that while safety practices are implemented, further improvements are essential to enhance worker well-being and safety stewardship in the region.
Dimensional Stability of Oil Palm Empty Fruit Bunch Fibre (OPEFB) Cement Board Over The Curing Period
Oil palm fruit bunch fibre bunch (OPEFB) is a byproduct of palm oil manufacturing. Empty fruit bunch (EFB) can be recycled into compost, renewable energy, and nutrients, reducing waste and making industry more environmentally friendly and cost-effective. Asbestos and synthetic fibre exposures pose health risks, particularly mesothelioma, due to their carcinogenic effects. Natural fibres offer a sustainable alternative with comparable mechanical properties, fire resistance, and crashworthiness. They can be used in cement composite materials for biodegradability, design flexibility, and sustainability. The ratio of mixed cement- fibre is set at 3.5:1, aiming for targeted density of 1300 kg/m³. The total number of samples is 9 samples empty fruit bunch cement board (EFBCB) with the dimensions size of 350×350×12 mm. To enhance the material’s properties, hot water treatment being used at 100°C for a duration of 2 hours for treating the EFB fibre. The testing was conducted at intervals of 7, 14, and 28 days of curing process. The results demonstrated notable declines in dimensional stability and mechanical performance over the curing period. The analysis of the dimensional stability of OPEFB fibre cement board (EFBCB) during the curing period revealed significant changes in both physical and mechanical properties. The results demonstrated how the reduction in thickness, density, and other physical changes impacted the dimensional stability and mechanical performance of the boards.
Oil Palm empty fruit bunch (OPEFB), Empty fruit bunch cement board (EFBCB), dimensional stability, physical and mechanical properties, thickness monitoring
Sugarcane Wasted Fibre as a Sustainable Sound Absorber at Different Thickness
Traditional sound absorption panels composed of synthetic materials are advantageous due to their efficacy in reducing noise levels. The utilisation of synthetic materials poses considerable health hazards and environmental issues that require urgent consideration. To reduce the adverse effects of synthetic materials, a feasible option is the utilisation of natural fibres, such as sugarcane bagasse. This study utilised sugarcane bagasse, along with gypsum powder and a bio-adhesive serving as a binder, to create panels of two distinct thicknesses (50 mm and 30 mm). The sound absorption performance was evaluated using an impedance tube test in accordance with BS EN ISO-10534-2:2001-transfer function method, spanning low to high frequencies. Moreover, the noise reduction coefficient is calculated using the formula to assess the sample's sound absorption capability. Results indicate that the sugarcane bagasse panel demonstrates favourable outcomes, particularly at lower frequencies for thicker specimens. The 50-mm-thick sample demonstrates peak sound absorption coefficients (SAC) of 0.82 at 400 Hz, but the 30-mm-thick sample attained a value of 0.69 at 800 Hz. Analysis of linear regression indicates that sound absorption performance enhances with increased sample thickness, as the 50 mm samples exhibit higher noise reduction coefficients (NRC) of 0.39, compared to the 0.36 coefficients of the 30 mm samples. The porous structure of sugarcane fibres enables the trapping of sound waves, hence facilitating noise reduction. switching from synthetic to natural fiber-based sound-absorbing panels, particularly those made from sugarcane bagasse, provides a feasible and sustainable approach to noise reduction across different sectors.
Heat waves in Southeast Asia are becoming increasingly common and intense, posing substantial challenges for the construction industry. As the heat waves are predicted to increase in the future, they will certainly impact construction project performance, specifically in terms of cost, time, and quality. This paper aimed to analyze the impact of heat waves on these project performances. A questionnaire survey using Microsoft Forms was used to gather the data. This paper focuses on 200 respondents from Grade 6 (G6) and Grade 7 (G7) contractors in Johor Bahru, Johor. The findings show the interrelated effects on time, cost, and quality. The productivity of workers decreased as they required longer time to rest, which led to delayed issues. Additionally, exposure of the material to heat and workers' focus on work influence the poor quality of the project. The heat forcing in additional safety measures and heat-related illnesses necessitate more labor, further escalating project costs. Therefore, the paper concludes that heat waves influence construction in Malaysia through an increased duration cost and risk of project completion associated with quality.
Investigation of Crack Depth on Reinforced Concrete Beam Using Vibration-Based Method
Basic types of damage to a concrete structure include cracks, which can lower the structure's stiffness and load-bearing capacity as well as causing failures and tragedies in buildings under construction. As a result, it's essential to keep an eye on the structural responses in order to assess the health of the buildings, guarantee their operational safety, and identify damage early on. Damage-related changes to the structures' physical characteristics, such as their natural frequency and mode shape that might modify the dynamic response. These parameter changes can be extracted to predict damage detection information, such as the presence, location, and severity of damage in a structure. Thus, in this study, two non-destructive test methods ambient vibration test and impact hammer test were carried out to determine the vibration behaviour of cracked and uncracked of simply supported beams. Moreover, the position of various crack depth from 0mm to 150mm with 50mm interval were determined at the midspan of 0.60m x 0.25m x 0.25m reinforced concrete beams. The result showed, the natural frequency of cracked beam is lower than uncracked beam. Besides, propagation path of wave altered differently with various crack depth. The severity of cracks also can be determined by observing the curve fitting graph where the wave pattern propagate.
Reinforced concrete beam, Crack depth, Vibration-based method, Ambient test, Impact hammer test
Enhancement Of Structural Integrity On Apron And Soil Settlement Behavior At Kompleks Penghulu Ayer Hitam, Muar Structures
Concrete apron failure, often linked to soil settlement, presents significant challenges in civil engineering and infrastructure development. This study investigates the mechanisms contributing to apron deterioration, including cracking, spalling, and structural instability, with a focus on soil settlement behavior. Field studies and laboratory tests such as atterberg limit, grain size analysis, compaction test, and consolidation tests were conducted. Results show the soil has a moderate plasticity index (9.9%), is well-graded gravel (Cu=3.75, Cc=1.5), with an optimum moisture content of 14.5% and a rapid consolidation coefficient (12.74 m²/year). These findings inform recommendations for improved apron designs. Geogrids are proposed as an effective solution to enhance stability and durability, addressing the complex interaction between soil and concrete structures.
Implementing Artificial Neural Networks and Mode Shape Curvature for Locating damage in Bridge Structures
Structural damage manifests as changes in a system’s geometry and material properties, leading to stiffness reduction and adversely impacting performance. These reductions alter modal parameters like natural frequencies and mode shapes, which can be analysed to identify damage. Modal analysis allows for the extraction of modal frequencies and shapes, enabling a detailed examination of mode shape curvature to locate structural issues accurately. Recently, artificial neural networks (ANNs) have proven to be highly effective in structural health monitoring, particularly due to their exceptional pattern recognition capabilities. This study presents a novel approach that combines mode shape curvature analysis and ANNs to detect damage in steel girder bridge structures. Through vibration-based fault detection, this approach overcomes limitations of traditional methods by using mode shape curvature as a reliable indicator of structural anomalies. Experimental evaluations compare the modal responses of intact and damaged structures, providing critical insights into changes in structural behaviour. A feed-forward neural network with two hidden layers is employed, trained on damage indices generated from mode shape curvature data. This trained ANN is then used to identify unknown damage locations within the structure, demonstrating high precision. Validation results further confirm the accuracy and reliability of this damage detection method. Overall, the study shows that ANNs trained with modal curvature data offer a robust and efficient approach for early damage detection in steel girder bridge structures, significantly enhancing safety and operational reliability. This innovative method contributes to advancing structural health monitoring, offering a valuable tool for maintaining the integrity of infrastructure, such as steel girder bridges.
Modulus of Elasticity and Tensile Strength for Laminated Zinc Composite Plate
The concept behind preparing the laminated zinc composite plate is based on the principles of Metal Matrix Composites (MMC) and utilizes recycled zinc sourced from construction sites. The objective of this study is to fabricate a composite plate with a target modulus of 10 GPa, ensuring superior stiffness and load-bearing capabilities. The composite plate is constrained to a maximum thickness of 2 mm. The composite plate design involves a single type of material zinc sheets arranged in multiple layers and bonded using epoxy adhesive glue. A total of seven (7) zinc sheet layers were combined. The epoxy adhesive consists of two components, resin and hardener, mixed in a 1:1 ratio. This combination forms a strong bond between the zinc sheets, enabling the composite plate to withstand high pressure without delamination. Previous studies have reported that zinc plates exhibit excellent mechanical properties, including ultimate strength (120 MPa), compressive strength (110 MPa), tensile strength (120 MPa), and flexural strength (100–150 MPa). Tensile tests conducted in the laboratory yielded maximum stress values of 348 MPa, 320 MPa, and 250 MPa for three different zinc composite plates. In conclusion, after thorough analysis and calculations, the average modulus of elasticity for the zinc sheet composite was determined to be 14.3 GPa, exceeding the initial design target of 10 GPa.
Composite plate, zinc sheet, strength, modulus of elasticity
Crack Assessment on a Residential Building Due to Peat Soil Settlement at Ayer Hitam, Muar
Frequent problems in structure that build on the peat soil is cracking. This is due to the settlement that occurred by the peat soil as it has low in bearing capacity. The crack occurred on the residential building have become the main concern as crack happened on building showed the earliest sign of degradation. The increasing number of visible cracks at residential building with varies in length and width has a doubtful taught either the residential building is safe or not to be used. Apart from cracking, the concrete strength of the residential building is a concerned as the crack occurred may reduce the concrete strength. A single-storey residential building at Kompleks Penghulu Mukim Ayer Hitam, Muar is used to perform field measurement with respect to the cracking and concrete strength. 25 number of visible cracks with different length and width has been detected while monitoring the building. The crack length and size were measured using ruler and measuring tape. For measuring the concrete strength, a non-destructive testing (NDT) was used using Schmidt Rebound Hammer and Ultrasonic Pulse Velocity (UPV). The total 15 point was tested on column and wall inside the residential house by using two modes of transmission for UPV testing which was semi-direct and indirect transmission. The result of both rebound number and UPV has been analyze using statistical evaluation. The result is then being compared with the previous researcher that using the same regression mode of linear and non-linear mode when doing the analysis. From the result, it is found that the regression model for rebound hammer is more reliable to be used as the regression coefficient value got is nearly to one. For overall cracking and concrete strength quality, it is also found that the residential building needs proper maintenance as the settlement still happened and it is affected the residential building’s safety.
Copyright (c) 2024 Journal of Structural Monitoring and Built Environment https://creativecommons.org/licenses/by-nc-sa/4.0
Comparison Between Conventional Method and Cradle-to-Cradle Method of Waste Management Method
Population growth, rapid development and Covid-19 outbreak contributes to the waste generation. Sustainable waste management procedures limit untreated debris disposal where this renewable method will benefit to the environment. Main objective of this study is to determine the best method of waste management that can be proposed to apply in Malaysia. Conventional method and cradle-to-cradle (C2C) method have advantages also disadvantages that will be considered to provide an overall comparison. This study’s methodology includes reviewing previous studies, obtaining data from project conducted at Solid Waste Research Center (SWRC), UTHM and afterwards analyzing the findings. Three elements such as environmental impact, process in producing new product and cost expenditures also considered to be discussed. This research concludes based on the results in comparison, Malaysia should practice the C2C waste management method as it is the best waste management technique due to the waste prevention at the end of any product's life cycle as a key.
Cracking Assessment of Reinforced Concrete Slab Using Impact Hammer Test
Impact hammer test is a vibration-based monitoring method used to detect cracking or damage in concrete structures by observing the vibration behavior such as the natural frequency, mode shapes and damping ratio. Damage or cracks in the structure can cause structure failure. The ability to quickly perform maintenance, if necessary, depends on the ability to identify damage or cracks. Concrete cracking has traditionally been detected via vibration analysis utilizing the impact hammer test. The main objectives of this research were to determine the natural frequency of the cracked and uncracked reinforced concrete slabs and to determine the depth of the crack using the impact hammer test. Two samples of reinforced concrete slabs were constructed in the laboratory. The reinforced concrete slabs were designed as Grade 25 concrete. After 28 days, the impact hammer test was conducted on the uncracked slabs. After that, the slabs were subjected to a four-point bending test with loads of 3 kN, 6 kN, 12 kN and 15 kN. For each load increase, the impact hammer test and the crack mapping were performed. The natural frequency of the cracked and uncracked slabs was compared after that. The natural frequency of both Slab 1 and Slab 2 decreased after the slab was cracked compared to before cracked. The width of the crack was also determined by analyzing the wave acceleration from the impact hammer test. The outcome demonstrated that the wave's acceleration increased as it propagates through the crack region. The percentage difference in the waves’ acceleration was calculated. The result was also compared with crack depth measurement from PUNDIT. The result showed that the location of the maximum crack width and crack depth was the same. It also justified that when the percentage difference of the acceleration decreased, the crack width increased. However, in previous studies, these findings had not been discussed yet. Therefore, further research needs to be done to understand the propagation of the wave on the cracked slab to validate the findings.
Comparison between Conventional Method and Cradle-to-Cradle Method of Waste Management Method
Concrete is a widely used material in the construction industry. Rice husk ash and coal bottom ash are by-product materials chosen to alternate the use of cement and sand in concrete production. Concerns about the long-term performance of seawater concrete structures incorporated with RHA-CBA have been obstacles to the developing uses of sustainable concrete due to the scarcity of knowledge and test data. Thus, the long-term performance of seawater concrete consisting of RHA as cement replacement and CBA as sand replacement on compressive strength and carbonation was evaluated in this study. To accomplish the study's goal, existing specimens aged 1 year and 4 months, and 2 years with different mixture series were used. In the mixture, seawater was utilized to fully replace freshwater, along with 10% RHA used to replace cement. Additionally, 10% to 100% CBA replaced the sand with a 10% increment. The specimens consisted of 68 cylindrical concretes in 100  100 mm and 100  200 mm exposed to indoor environmental conditions. Compressive strength and carbonation tests were performed to assess the strength and durability of the concrete. The results indicate that the concretes' strength grows insignificantly in the atmospheric environment within exposure age. After a prolonged period, the specimen's strength development reduces as the amount of CBA in the concrete mixture increases. Meanwhile, test results revealed that RHA-seawater concrete containing CBA exhibited minimal carbonation after 2 years of aging. Higher incorporation of CBA in the concrete mixture leads to a greater carbonation rate, reducing the concrete’s alkalinity. The findings of this study contribute to the understanding and advancement of long-term performances of sustainable concrete materials for construction practices.
Building Defects Investigation - Two Case Studies On Steel And Reinforced Concrete Structures
The purpose of this paper is to present two case studies involving the initial assessment of potential causes of building structures that are in doubt. The investigation involving a fertilizer-manufacturing building and residential buildings. The corrosion problems that occurred in the industrial building were severe, and necessitating an assessment to gauge the building's safety condition. For the residential building, a visual inspection was conducted not only on the residential structures themselves but also on the surrounding infrastructures, in order to justify whether the nearby construction works were responsible for the problems. From the investigation on the industrial building, corrosion seems to be the primary problem and a potential cause of structural instability. The severity can be seen as most of the steel structural elements exhibited signs of material loss from their surfaces. From the evaluation through visual inspection and tests, the aggressive environment and insufficient maintenance are the main contributors to the corrosion related damage. Concerning the residential building, based on the inspection of the nearest infrastructures, no fractures were identified that could be attributed to the nearby construction works. Therefore, it may seem that the on-going project may not have affected the existing residential housing located nearby.