Journal of Science, Technology, and Innovation
Inventa: Journal of Science, Technology, and Innovation is a peer-reviewed open-access journal published by CV Scripta Intelektual Mandiri. It publishes original research and applied studies in science, technology, and innovation, including fields such as engineering, ICT, materials science, renewable energy, and environmental technology. The journal is published three times a year (April, August, December) and operates under a no-fee policy. All articles are licensed under the Creative Commons Attribution 4.0 (CC BY 4.0) license.
A Comparative Technical and Economic Analysis of Flexible Pavement Design versus Rigid Pavement Design in Highway Projects
The selection of pavement type is a strategic decision in highway planning because it directly influences structural performance and cost efficiency throughout the service life. This study aims to compare the technical and economic performance of flexible and rigid pavements using a quantitative comparative simulation approach. The simulation was conducted on a 5 km arterial road with a subgrade California Bearing Ratio (CBR) of 5%, an annual traffic growth rate of 4.5%, and a 20-year design life. Pavement design was developed based on the 2017 Manual Desain Perkerasan Jalan (MDPJ), while the economic evaluation employed the Life Cycle Cost Analysis (LCCA) method with an 8% discount rate. The results indicate that flexible pavement requires a multilayer structure with a total thickness of approximately 50 cm, whereas rigid pavement utilizes a 25 cm concrete slab. Although the initial construction cost of flexible pavement (IDR 18.50 billion) is lower than that of rigid pavement (IDR 24.20 billion), the total life cycle cost of rigid pavement (IDR 22.47 billion) is lower than that of flexible pavement (IDR 24.72 billion). These findings demonstrate that rigid pavement is a more cost-effective alternative for heavily trafficked roads when evaluated from a life cycle cost perspective.
Engineering Economics, Flexible Pavement, Highway Project, Life Cycle Cost Analysis, Rigid Pavement.
Copyright (c) 2026 Nugraha Ahmad Santorini, Buyung Mantap (Author) https://creativecommons.org/licenses/by/4.0
Analysis of Drainage Channel Dimension Calculations for Rimbo Recap Village Based on Rainfall Data from South Curup, 2018–2022
Drainage channels are essential infrastructure for controlling stormwater runoff and reducing the risk of inundation and flooding. Accurate drainage dimension planning requires reliable hydrological analysis based on local rainfall characteristics. This study aimed to determine the appropriate dimensions of a drainage channel in Rimbo Recap Village, South Curup District, using rainfall data collected from 2018 to 2022. A quantitative approach was employed by integrating field observations, documentation, hydrological analysis, and hydraulic analysis. Maximum rainfall data were analyzed to estimate design rainfall, rainfall intensity, and design discharge using the Rational Method, followed by hydraulic calculations to determine the channel dimensions. The analysis produced a design discharge of 0.456 m³/s, while the planned channel capacity reached 0.511 m³/s, indicating that the proposed dimensions were hydraulically adequate. The recommended open rectangular channel has a width of 0.50 m, a water depth of 0.31 m, and a freeboard of 0.39 m, providing sufficient capacity to safely convey the design runoff under local hydrological conditions. The findings provide a practical reference for designing rural drainage systems based on local rainfall characteristics to improve flood mitigation and sustainable water management.
Design Discharge, Drainage Channel, Hydraulic Analysis, Hydrological Analysis, Rainfall.
Copyright (c) 2026 Haris Fadillah, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Analysis of the Quality and Performance of Wave Breakwater Structures in the Panjang Beach Area, Bengkulu Province
Pantai Panjang in Bengkulu Province is a strategic coastal area that supports tourism, local economic activities, and environmental protection but is highly vulnerable to wave attack and coastal erosion due to its direct exposure to the Indian Ocean. This study aims to evaluate the construction quality and performance of rubble mound breakwaters in reducing wave energy and controlling shoreline erosion. An empirical descriptive approach was employed through field observations, measurements at six observation points, drone documentation, interviews, and secondary data analysis. Construction quality was assessed based on material suitability, structural geometry, and damage level, while performance evaluation focused on wave attenuation, abrasion reduction, and overtopping occurrence. The results indicate that most breakwater segments remain in good condition, with an average wave transmission coefficient of 0.32 and approximately 63% reduction in shoreline erosion. Lower performance was identified at locations with inadequate material dimensions and reduced crest elevation. The findings emphasize the importance of regular maintenance and periodic performance evaluation to sustain the long-term effectiveness of coastal protection structures.
Breakwater, Coastal Erosion, Coastal Protection, Construction Quality, Pantai Panjang.
Copyright (c) 2026 Cok Da Gibson, Buyung Mantap (Author) https://creativecommons.org/licenses/by/4.0
Development Plan for Seluma Public Elementary School No. 142, Ulu Talo Subdistrict, Seluma Regency, under the 2026 Educational Institution Revitalization Program
The School Revitalization Program is a strategic government initiative aimed at improving the quality of educational facilities and infrastructure by providing safe, adequate, and standards-compliant school buildings. This study aims to develop the technical planning for the construction of SD Negeri 142 Seluma under the 2026 School Revitalization Program. The study employed a qualitative descriptive approach through field research, including interviews, building condition surveys, dimensional measurements, damage assessment based on the PUPR Building Damage Assessment Form, and technical document analysis. The results indicate that the school received five revitalization components: rehabilitation of three classrooms, rehabilitation of the library, construction of a new administration (ADM) building, construction of a school health unit (UKS), and development of an assembly field. The assessed building damage was classified as moderate, with damage levels ranging from 33.38% to 41.99%. The planning process produced detailed engineering drawings, technical specifications, and a cost estimate totaling IDR 1,141,000,000. The resulting technical planning provides a reliable basis for self-managed construction implementation while supporting improvements in the quality of educational services.
Building Planning, Cost Estimation, Field Study, School Facilities and Infrastructure, School Revitalization Program.
Copyright (c) 2026 Hengki Saputra, Buyung Mantap (Author) https://creativecommons.org/licenses/by/4.0
A Comparative Analysis of Construction Costs and Duration for Building Structures Using Reinforced Concrete and Light-Gauge Steel Systems
The selection of a structural system is an important factor in determining the success of construction projects, particularly in terms of cost efficiency and implementation time. Reinforced concrete remains a widely used conventional method due to its high structural durability, while lightweight steel has emerged as an alternative construction system with practical characteristics and faster installation processes. This study aims to compare the construction costs and implementation time between reinforced concrete and lightweight steel systems for a two-story residential building in Bengkulu. The research employed an empirical comparative study through identical building modeling, work volume calculations, unit price analysis based on SNI standards, and construction duration estimation. The results indicate that lightweight steel provides lower construction costs and shorter implementation time compared with reinforced concrete. Lightweight steel is recommended for projects prioritizing time and resource efficiency, while reinforced concrete remains a suitable option for buildings requiring higher structural durability.
Comparative Analysis, Construction Cost, Implementation Time, Lightweight Steel, Reinforced Concrete.
Copyright (c) 2026 Eygen Rapendes, Buyung Mantap (Author) https://creativecommons.org/licenses/by/4.0
Analysis of Soil Characteristics Through Soil Investigation as a Basis for Building Foundation Design
Soil investigation is an essential stage in construction planning because soil characteristics influence the safety and stability of building foundation systems. This study aims to analyze soil characteristics through soil investigation activities as a basis for determining appropriate foundation types for building structures. The research method used was descriptive quantitative through field investigation and laboratory testing. Data were obtained through soil boring, Standard Penetration Test (SPT), soil sampling, and laboratory tests including water content, specific gravity, Atterberg limits, shear strength, and consolidation tests. The results indicate variations in soil characteristics based on depth, density values, mechanical parameters, and soil bearing capacity, which serve as the basis for foundation system evaluation. This study confirms that accurate soil investigation data can improve foundation design reliability, reduce the risk of construction failure, and support efficient building planning. An integrated approach combining field testing and laboratory analysis provides a more comprehensive understanding of soil behavior as a structural supporting medium.
Foundation, Soil Characteristics, Soil Bearing Capacity, Soil Investigation, Standard Penetration Test (SPT).
Copyright (c) 2026 Buyung Mantap, Rendi Zoeyantara (Author) https://creativecommons.org/licenses/by/4.0
Economic and Technical Feasibility Analysis of the Central Business District Toll Road Construction Project Using the Value Engineering Method
The imbalance between increasing vehicle volumes and road infrastructure development has triggered congestion escalation in urban central business areas. This study aims to evaluate the economic and technical feasibility of a 12.5-kilometer toll road development project and optimize construction costs through a Value Engineering approach. The analysis was conducted using the Net Present Value (NPV), Internal Rate of Return (IRR), Benefit-Cost Ratio (BCR), and Payback Period indicators with a 30-year investment period. The initial analysis indicates that the project is financially feasible, with an NPV of IDR 450.2 billion, an IRR of 12.4%, and a BCR of 1.28. The implementation of Value Engineering through precast system optimization and material substitution resulted in construction cost savings of 14.2% or IDR 185 billion. After optimization, the NPV increased to IDR 635.7 billion, the IRR improved to 14.1%, the BCR reached 1.45, and the Payback Period was reduced to 11.8 years. The integration of economic evaluation and value engineering provides a more efficient and sustainable toll road development strategy. This approach can serve as a basis for urban infrastructure investment decision-making by considering technical, economic, and long-term risk aspects.
Engineering Economy, Infrastructure Investment, NPV, Toll Road, Value Engineering
Copyright (c) 2026 Buyung Mantap, Frando Heriss Mamuri (Author) https://creativecommons.org/licenses/by/4.0
Design of an Integrated System for Custom Vise Production at SSML
Small Scale Manufacturing Laboratory (SSML) has the capability to manufacture custom vises based on customer requirements and specifications. However, the ordering and production management processes are still performed manually, resulting in limited coordination and production monitoring. This study aimed to design an integrated Engineer-to-Order (ETO)-based production system for custom vises with ordering and production monitoring features. The research employed a Research and Development (R&D) approach consisting of needs identification, literature review, system design, production process simulation using FlexSim, and the development of Standard Operating Procedures (SOPs) and Occupational Safety and Health (OSH) procedures. The results indicate that the proposed system integrates order management, product specification management, production progress monitoring, and production time estimation into a structured platform. Customer and administrator dashboards improve information management, while the production simulation visualizes workflow prior to operational implementation. The proposed system has the potential to enhance the effectiveness of custom vise production management and improve service quality for both internal and external customers.
Custom Vise, Engineer-To-Order, Production Monitoring, Production Simulation, Production System.
Copyright (c) 2026 Reza Aditya Fauzi, Rijki Nurlaeli, Muhamad Ridwan, Muhammad Harsya Alfarisi, Lisye Fitria (Author) https://creativecommons.org/licenses/by/4.0
Design of a Web-Based Occupational Safety and Health (OSH) Reporting Information System to Improve Communication and Data Management at PT XYZ
This study aimed to design a website-based Occupational Safety and Health (OSH) reporting information system to improve communication effectiveness and data management at PT XYZ. The main issues included a manual reporting system, limited accessibility due to the distance between divisions, and low employee participation in reporting workplace hazards. The study adopted the Industrial and Engineering Systems Body of Knowledge (IISE BOK), integrating the principles of Safety, Information Engineering, and Systems Design. The research stages consisted of problem identification through workplace observation and environmental measurements, system design, and functional evaluation. The results indicated that most workplace environmental parameters remained below the permissible exposure limits; however, noise levels reached 83.4 dBA and humidity reached 69%, indicating the need for continuous monitoring. In addition, oil spills and inadequate waste management practices were identified. The proposed system supports real-time reporting, photo upload, centralized data storage, and QR Code access, thereby enhancing reporting effectiveness, data management, and the implementation of an OSH culture within the company.
Industrial and Engineering Systems Body of Knowledge (IISE BOK), Information System, Occupational Safety and Health, OSH Culture, Website.
Copyright (c) 2026 Adela Kusuma Yudhani, Sevilla Muthia Ariawan, Shafira Aulia, Siti Julianti (Author); Alif Ulfa Afifah (Translator) https://creativecommons.org/licenses/by/4.0
The Effect of Product Quality and Developer Service on Consumer Satisfaction with Commercial Housing in Bengkulu City
The rapid growth of the property sector in Bengkulu City has intensified competition among developers in meeting the increasing demand for quality housing. This study aims to examine the influence of product quality and developer service quality on customer satisfaction in commercial housing developments in Bengkulu City. A quantitative survey approach was employed involving 100 respondents selected through purposive sampling. Data were collected using questionnaires and analyzed through validity and reliability tests, multiple linear regression, t-test, F-test, and the coefficient of determination (R²). The results indicate that both product quality and developer service quality have a positive and significant effect on customer satisfaction, both partially and simultaneously. Product quality was identified as the most dominant factor influencing customer satisfaction. The proposed model explained 71% of the variance in customer satisfaction, while the remaining 29% was attributed to factors beyond the scope of the study. These findings provide practical insights for developers to improve building quality and service performance to enhance customer satisfaction and strengthen market competitiveness.
Bengkulu City, Commercial Housing, Customer Satisfaction, Developer Service Quality, Product Quality.
Copyright (c) 2026 Recky Kurniawan, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Upgrading of the Road in Air Lang Village, Sindang Dataran Subdistrict, Rejang Lebong Regency, in 2025
Road infrastructure plays an important role in supporting community mobility, agricultural product distribution, and regional economic growth. The condition of Air Lang Village Road, Sindang Dataran District, Rejang Lebong Regency, consisted of a Lapen (Penetration Macadam) pavement that had deteriorated, requiring reconstruction using a flexible pavement structure. This study aimed to describe the stages of road reconstruction implementation and to calculate the work volumes based on the design dimensions. A quantitative descriptive method was employed using data obtained from field observations, engineering drawings, technical documents, and the 2018 General Specifications for Highways (Bina Marga). The reconstructed road section is 4,450 m long, with work volumes of 4,272.00 m³ for Selected Embankment, 3,137.25 m³ for Aggregate Base Class B, 3,070.50 m³ for Aggregate Base Class A, 1,201.50 m³ for Asphalt Concrete Binder Course (AC-BC), and 801.00 m³ for Asphalt Concrete Wearing Course (AC-WC). The results indicate that implementing the construction in accordance with technical specifications produced a stronger pavement structure, extended the service life of the road, and improved user comfort, safety, and transportation service quality.
AC-BC, AC-WC, Flexible Pavement, Road Reconstruction, Work Volume.
Copyright (c) 2026 Wahyu Darmawan, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Evaluation of Construction Labor Productivity Using the Work Sampling Method in Concrete Structure Projects
Labor productivity is a critical factor influencing the success of construction projects in terms of cost, quality, and schedule performance. This study aimed to evaluate labor productivity in reinforced concrete structural works, including reinforcement, formwork, and concreting, using the Work Sampling method. A quantitative observational approach was employed through random observations to classify workers' activities into three categories: Effective Work, Essential Contributory Work, and Idle Time. The observation data were analyzed using the Labor Utilization Rate (LUR) indicator to measure the efficiency of labor time utilization. The results showed that the project's average LUR was 55.50%, indicating satisfactory labor productivity as it exceeded the industry benchmark of 50%. Reinforcement work achieved the highest LUR of 62.10%, while concreting recorded the lowest LUR of 47.10% due to high Idle Time caused by delays in ready-mix concrete delivery, concrete pump interruptions, and inefficient material layout. These findings provide a basis for improving logistics management and work coordination to enhance productivity in reinforced concrete construction projects.
Idle Time, Labor Productivity, Labor Utilization Rate, Reinforced Concrete Structure, Work Sampling.
Copyright (c) 2026 Riyan Putra Pratama, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Evaluation of Flexible Pavement Thickness Using the 2024 Manual for Pavement Design (MDP) on the Road Section Connecting Teladan Village and Tempel Rejo Subdistrict, South Curup District, Rejang Lebong Regency
The Teladan Village–Tempel Rejo Subdistrict Road in South Curup District, Rejang Lebong Regency, has experienced a decline in service quality due to increased traffic volume, surface damage, and limitations in the supporting conditions of the road structure. This study aims to evaluate the required thickness of flexible pavement using the 2024 Pavement Design Manual (MDP) method based on traffic characteristics and subgrade bearing capacity. The research method employed an empirical approach through field surveys, collection of Average Daily Traffic (ADT) data, observation of pavement and drainage conditions, and California Bearing Ratio (CBR) testing. Analysis was conducted through vehicle classification, calculation of the Vehicle Damage Factor (VDF), Equivalent Standard Axle Load (ESAL), and Cumulative Equivalent Standard Axle Load (CESAL), and determination of the pavement structure in accordance with MDP 2024. The results of the study showed an average traffic volume of 249 vehicles per day with a subgrade CBR value of 6%. The recommended pavement structure consists of 4 cm of AC-WC, 6.5 cm and 8 cm of AC-BC, 20 cm of Class A aggregate, and 15 cm of Class B aggregate.
Pavement Design Manual, Flexible Pavement, Traffic, CBR, CESAL
Copyright (c) 2026 Jaka Malis Irawan, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Economic Analysis of the Design and Structural Reliability of Rigid Pavements in the Trans-Sumatra Toll Road Construction Project, Section X-
The construction of the Trans-Sumatra Toll Road requires a pavement design strategy capable of ensuring both structural reliability and economic efficiency throughout the infrastructure’s service life. This study aims to analyze the structural performance of rigid pavement and its economic feasibility through a Life Cycle Cost Analysis (LCCA) approach for the Trans-Sumatra Toll Road Project, Section X-Y. The research methodology employs an empirical study based on engineering analysis and technical-economic simulation, utilizing traffic data, subgrade characteristics, material parameters, and life cycle cost modeling. The results show that the optimal design consists of a concrete slab with a strength of f’c 45 MPa and a thickness of 30 cm, a 10-cm layer of lean concrete, and a 15-cm layer of Class A aggregate to withstand a cumulative load of 1.2 × 10⁸ ESAL over 40 years. The economic analysis yielded a positive NPV of Rp4.235 billion, an IRR of 13.42%, and a BCR of 1.28. Sensitivity testing showed that the investment remains feasible despite changes in construction costs and decreases in traffic volume. This study contributes to the development of road infrastructure evaluation based on the integration of structural performance and life-cycle economics.
Rigid Pavement, Life Cycle Cost Analysis, Engineering Economics, Structural Reliability, Trans-Sumatra Toll Road
Copyright (c) 2026 Imawan Sumanto, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Performance Analysis of the Supervising Consultant for the Merah Putih Fishing Village National Strategic Project in Penago 1 Village, Ilir Talo Subdistrict, Seluma Regency, Bengkulu Province
This study aims to analyze the performance of the supervising consultant on the Merah Putih Fishing Village National Strategic Project in Penago I Village, Ilir Talo Subdistrict, Seluma Regency, Bengkulu Province. The study employs an empirical approach using a case study design, involving field observations, semi-structured interviews, and a review of project documents, including working drawings, supervision reports, progress reports, minutes of meetings, and contract documents. The analysis was conducted based on indicators of quality control, time control, cost control, contract administration, coordination among stakeholders, and risk management, while data validity was strengthened through triangulation of sources, methods, and documents. The results of the study indicate that the supervising consultant was able to ensure that the quality of the work complied with technical specifications through periodic inspections and documented corrective actions. Time control faced challenges due to rainfall, peatland conditions, and material distribution; however, contract administration management, progress verification, and cross-stakeholder coordination were able to maintain the effectiveness of project implementation.
Contract Administration, Supervising Consultant, Risk Management, National Strategic Projects, Project Governance
Copyright (c) 2026 Rezi Munizar, Yogi Efriono (Author) https://creativecommons.org/licenses/by/4.0
Construction of a Box Culvert for Flood Mitigation on the Main Road in Talang Rimbo Village, Rejang Lebong Regency
Urban flooding in areas with high transportation activity is an infrastructure problem influenced by increased surface runoff, limited drainage capacity, and changes in land-use characteristics. This study aims to analyze design flood discharge, evaluate existing drainage capacity, and design box culvert dimensions as a flood control solution on the Main Road of Talang Rimbo Village, Rejang Lebong Regency. The research method employs a quantitative approach based on hydrological and hydraulic analysis through calculations of design rainfall using the Gumbel distribution, Mononobe rainfall intensity, and Rational Method flood discharge, as well as an evaluation of channel capacity using Manning’s equation. The results show that the design flood discharge reaches 5.54 m³/s, while the capacity of the existing channel is only 0.28 m³/s, resulting in a capacity deficit of 5.26 m³/s. A box culvert with dimensions of 1.6 m × 1.8 m can increase flow capacity and provide a technical solution to the flooding problem. This study contributes to the development of urban drainage designs based on hydrological and hydraulic approaches to enhance infrastructure resilience against flood risks.
Box Culvert, Urban Drainage, Design Flood Discharge, Hydraulics, Flood Mitigation
Copyright (c) 2026 Dwi Aji Ttriono, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Analysis of the Implementation of Occupational Safety and Health (OSH) in Construction at the Project to Build the State Elementary School No. 7 in Central Bengkulu
The construction industry has a high rate of workplace accidents, making the implementation of Occupational Safety and Health (OSH) a fundamental aspect of project success. This study aims to analyze the level of OSH implementation, identify factors hindering implementation, and formulate strategies to improve safety in the Construction Project of the State Elementary School No. 7 in Central Bengkulu. The research method employed a mixed-methods approach through field observations based on the SMKK checklist and a Likert-scale questionnaire administered to 30 respondents, consisting of project management, foremen, and construction workers. The results showed a 63% compliance rate with OSH implementation, categorized as “adequate,” while the use of secondary PPE, emergency response facilities, and safety supervision were identified as areas requiring improvement. The main inhibiting factors include low worker discipline, limited supervision, and suboptimal safety education. The study recommends strengthening the safety culture through routine training, periodic inspections, and work-activity-based risk control to support the achievement of safe construction.
Construction Safety, Construction Safety Management System, Occupational Safety and Health (OSH) Evaluation, Risk Management, Building Projects.
Copyright (c) 2026 Sofyan Ansori, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Planning for the Clean Water Supply System (SPAM) in Kampung Delima Village, East Curup Subdistrict, Rejang Lebong Regency
The availability of clean water that meets standards for quality, quantity, and continuity is a strategic necessity for the development of basic infrastructure in rural communities. This study aims to plan a Clean Water Supply System (SPAM) for Kampung Delima Village, East Curup Subdistrict, Rejang Lebong Regency, through an analysis of water needs, distribution network design, and evaluation of the system’s hydraulic performance. The study employed an empirical approach involving the collection of topographic data, water source characteristics, and demographic data, which were then analyzed using geometric projection methods, water demand standards from the Directorate General of Public Works, and piping network simulations using EPANET 2.2. The results show that the population in 2046 is projected to reach 3,250 people, with an average water demand of 4.13 liters/second and a peak hourly flow rate of 6.19 liters/second. The system was designed using a gravity-fed method with a reservoir capacity of 71.5 m³ and an HDPE pipeline network. Hydraulic simulations show that residual pressure and flow velocity meet technical service criteria. This study produced an adaptive, efficient, and sustainable drinking water supply system design suited to the characteristics of rural areas.
Drinking Water Supply System, Population Projections, Pipe Hydraulics, EPANET, Gravity System
Copyright (c) 2026 Samsul Huda, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Analysis of the Effect of Material Quality on the Compressive Strength of Concrete in High-Rise Building Construction
Concrete is the primary material used in the construction of high-rise buildings because it can withstand compressive loads and ensure long-term structural stability. This study aims to analyze the effect of constituent material quality on concrete compressive strength through a laboratory experimental approach. The research method utilized two variations of concrete mixes with a design strength of fc′=30 MPa: one using standard-grade materials and the other using substandard materials with high aggregate silt content and suboptimal coarse aggregate gradation. Tests were conducted on 150 × 300 mm cylindrical specimens at 7, 14, and 28 days using a compression testing machine. The results showed that concrete made with standard materials achieved a compressive strength of 31.2 MPa, while concrete made with substandard materials reached only 24.5 MPa—a 18.4% reduction from the design strength. These findings indicate that material quality plays a crucial role in determining concrete density, internal bond strength, and the structural reliability of multi-story buildings.
Concrete, Compressive Strength, Material Quality, Aggregate, Multi-Story Buildings
Copyright (c) 2026 Andika Candra, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Open Drainage Planning at Simpang Nangka, Selupu Rejang Subdistrict, Rejang Lebong Regency
A drainage system that is unable to accommodate runoff discharge is one of the factors causing flooding, which impacts road service functionality and infrastructure sustainability. This study aims to design an open drainage system at Simpang Nangka, Selupu Rejang Subdistrict, Rejang Lebong Regency, through an evaluation of existing conditions, hydrological analysis, hydraulic capacity calculations, and the preparation of construction cost estimates. The study employed an empirical approach through field surveys, rainfall data collection, design flow analysis using the rational method, and channel capacity calculations using Manning’s equation. The results indicate that the existing channel is unable to optimally convey runoff due to limitations in its dimensions and physical condition. The design for the new channel specifies a width of 0.3 meters, a water level of 0.2 meters, and a freeboard of 0.5 meters, capable of conveying a flow rate of 0.444 m³/s. The estimated construction cost of Rp118,413,000.00 demonstrates the feasibility of implementing this design as a flood control solution based on local characteristics.
Open Drainage, Design Flow, Channel Hydraulics, Infrastructure Planning, Road Flooding
Copyright (c) 2026 Ramos Yusgima, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Budget Planning and Feasibility Analysis for the Construction of Type 36 Residential Homes as Rental Properties (Based on NPV, IRR, and Payback Period)
This study aims to analyze the budget planning and investment feasibility of constructing Type 36 residential units to be used as rental housing, using the Net Present Value (NPV), Internal Rate of Return (IRR), and Payback Period (PP) indicators. The method used is an empirical study with a quantitative approach that integrates construction engineering and engineering economics analysis. The research stages included calculating the volume of work, preparing a Cost Budget Plan based on a Unit Price Analysis, preparing cash flow projections over the investment’s lifespan, and evaluating financial feasibility using the concept of the time value of money. The results show that the initial investment required for constructing a Type 36 house is Rp325,000,000, with the majority of costs attributed to structural work and masonry. Cash flow simulations demonstrate the project’s ability to generate stable rental income throughout the investment period. The feasibility analysis yielded a Net Present Value (NPV) of Rp29,617,428, an Internal Rate of Return (IRR) of 12.84%, and a Payback Period of 8.4 years. These values meet the criteria for a viable investment because they generate positive economic value added, a rate of return higher than the minimum acceptable rate of return (MARR) of 10%, and a payback period that remains within the investment horizon.
Cost Budgeting, Type 36 Residential Homes, Real Estate Investment, Net Present Value, Internal Rate of Return
Copyright (c) 2026 Iqbal Haqi, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Risk Assessment of Musculoskeletal Disorders Among Furniture Workers Using the REBA and RULA Methods as a Basis for Workstation Design Innovation
Raw material measuring activities in the furniture industry are commonly performed on the floor, forcing workers to maintain prolonged squatting, bending, and neck flexion postures that increase the risk of Musculoskeletal Disorders (MSDs). This study aimed to evaluate ergonomic risk using the Rapid Entire Body Assessment (REBA) and Rapid Upper Limb Assessment (RULA) methods as the basis for developing an ergonomic workbench design. A descriptive quantitative approach was employed through observation, interviews, documentation, work posture assessment, and anthropometric measurements of five workers. The results indicated a REBA score of 12 (Very High Risk) and a RULA score of 7 (Investigate and Implement Change). Based on these findings, an anthropometry-based ergonomic workbench was designed to improve working posture and increase production efficiency, reducing working time from 36 minutes to 23.5 minutes (34.7%). The proposed innovation is expected to reduce MSD risks while improving occupational safety, comfort, and productivity.
Ergonomics, Ergonomic Workbench, Furniture Industry, Musculoskeletal Disorders (MSDs), REBA and RULA.
Copyright (c) 2026 Dedy Iskandar, Sugina Sugina, Putri Septiani Lestari (Author) https://creativecommons.org/licenses/by/4.0
Analysis of Raw Material Inventory Control Using the Economic Order Quantity (EOQ) Method: A Case Study at PT Maju Bersama Industri
Raw material inventory control is one of the crucial aspects in maintaining the continuity of production processes in manufacturing companies. Inaccuracy in determining the amount of raw material orders often causes two opposing problems, namely excess inventory (overstock), which results in increased storage costs, or inventory shortages (stockouts), which can disrupt the overall production process. This study aims to analyze raw material inventory control at PT Maju Bersama Industri by applying the Economic Order Quantity (EOQ) method as a quantitative approach to determine the most economical order quantity. The research method used is descriptive quantitative research with primary data obtained through direct interviews with the production manager and secondary data from the company’s inventory reports for one year. Based on the calculation results, the EOQ value obtained is 1,549 units per order, the optimal ordering frequency is 15 times per year, the total inventory cost is Rp7,745,967, the safety stock is 200 units, and the Reorder Point (ROP) is 600 units. The results of this study indicate that the consistent implementation of the EOQ method can help companies minimize total inventory costs while maintaining raw material availability so that production processes can run smoothly and efficiently.
Economic Order Quantity, Inventory Control, Inventory Cost, Reorder Point, Safety Stock.
Copyright (c) 2026 Denny Andwiyan, Jawahir Jawahir, Patrick Andraes Napitupulu (Author) https://creativecommons.org/licenses/by/4.0
Assessment of Road Damage Levels Using the PKRMS Method (Provincial and Regency Road Management System) (Case Study: Central Bengkulu Regency)
Road deterioration is a major transportation infrastructure issue influenced by various factors, including environmental conditions, pavement material characteristics, subgrade stability, construction processes, heavy vehicle loads, and increasing traffic volume. This study aims to evaluate road damage levels and determine appropriate treatment recommendations for road sections in Central Bengkulu Regency using the Provincial Kabupaten Road Management System (PKRMS) method. The research method was conducted through field surveys to collect road inventory and pavement condition data, followed by data processing and analysis using the PKRMS application. The evaluation results indicate variations in road conditions ranging from good to severely damaged, with recommended treatments including routine maintenance, periodic maintenance, and rehabilitation. The implementation of PKRMS provides data-based information that supports more effective planning and management of regional road maintenance. This study demonstrates that the application of technology-based road management systems can improve the accuracy of infrastructure maintenance priority determination.
Condition Evaluation, PKRMS, Road Damage, Road Management, Road Maintenance
Copyright (c) 2026 Edo Jaya Saputra, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Analysis of the Impact of Drilled Well Construction on the Kemiling Permai 5 Subsidized Housing Complex
Clean water is a basic necessity that plays an essential role in supporting public health, sanitation, and daily activities. Limited access to clean water in residential areas encourages groundwater utilization through drilled wells as an alternative water supply solution. This study aims to analyze the impacts of drilled well development at Kemiling Permai 5 Subsidized Housing on clean water fulfillment, social, economic, and environmental aspects. This research employed a descriptive qualitative method using observation, interviews, documentation, and literature studies for data collection. Data analysis was conducted through data reduction, data presentation, and conclusion drawing. The findings indicate that drilled well development improves clean water availability, community comfort, household economic efficiency, and public participation in facility management. However, sustainable groundwater management is required to maintain water quality and availability while preventing environmental degradation. This study provides insights into the importance of integrating technical, social, and environmental considerations in managing drilled well systems within subsidized residential areas.
Clean Water, Drilled Well, Groundwater, Subsidized Housing, Sustainability.
Copyright (c) 2026 Rezi Munizar, Revva Zamriansyah (Author) https://creativecommons.org/licenses/by/4.0
The Effectiveness of Installing Speed Bumps in Improving Traffic Safety in Bengkulu City
Speed humps or speed bumps are traffic control facilities commonly implemented in residential areas to improve road user safety by reducing vehicle speed. This study aims to evaluate the conformity of speed hump dimensions and technical specifications with the provisions of Ministerial Regulation No. 14 of 2021 and to analyze their effectiveness in reducing vehicle speed in Bengkulu City. A descriptive research method was applied through field observations, physical dimension measurements, vehicle speed surveys, and community perception analysis. The results indicate that several speed humps do not comply with technical standards, particularly in terms of height, width, and marking requirements. The presence of speed humps reduces vehicle speed by 24–42%, although the resulting speed remains above the ideal limit of below 10 km/h. The findings highlight the need for proper planning, regulatory-based design implementation, and construction supervision to optimize speed hump functions while ensuring road safety and user comfort.
Road Control Devices, Speed Hump, Traffic Engineering, Traffic Safety, Vehicle Speed Reduction.
Copyright (c) 2026 Zefri Yedi, Rezi Munizar (Author) https://creativecommons.org/licenses/by/4.0
Technical and Economic Feasibility Analysis of the Construction of Section X of the Toll Road Using the Life Cycle Cost Method
The imbalance between traffic volume growth and road infrastructure capacity has intensified congestion, reduced logistics efficiency, and increased emissions along urban and intercity transport corridors. This study evaluates the technical and engineering-economic feasibility of the proposed 15.5 km Section X Toll Road using the Life Cycle Cost (LCC) approach. An empirical quantitative method was employed by integrating road capacity analysis, geometric design, rigid pavement design, and investment evaluation using Net Present Value (NPV), Internal Rate of Return (IRR), Benefit–Cost Ratio (BCR), and Payback Period (PP) indicators. The results indicate that the proposed toll road reduces the degree of saturation of the existing arterial road from 0.85 to 0.42. Economic evaluation produced a positive NPV of IDR 542 billion, an IRR of 12.45%, a BCR of 1.18, and a payback period of 14 years and 3 months. Sensitivity analysis confirms that the project remains financially feasible under a 15% increase in construction costs and a 10% decline in toll revenue. These findings demonstrate that the Section X Toll Road is technically feasible, economically viable, and capable of supporting sustainable infrastructure investment.
Engineering Economy, Investment Feasibility, Life Cycle Cost, Toll Road, Transportation Infrastructure.
Copyright (c) 2026 Anugrah Heris Santri, Rezi Munizar, Hendret Susanto (Author) https://creativecommons.org/licenses/by/4.0
Analysis of the Sebelat–Simpang DPRD (Tugu Hiu) Road Preservation Project via the E-Catalog
The Sebelat–Simpang DPRD (Tugu Hiu) Road is one of the strategic transportation corridors in North Bengkulu Regency, Indonesia, supporting the distribution of goods, public mobility, and regional economic activities. Deterioration of pavement conditions due to aging infrastructure and increasing traffic volumes necessitates road preservation to maintain service performance. This study aims to analyze the implementation of the road preservation package through the Electronic Catalog (E-Catalog) procurement system by evaluating existing pavement conditions, work volume and activities, procurement cost efficiency, procurement time efficiency, and post-preservation pavement performance. A quantitative descriptive method with a case study approach was employed using field survey data and project technical documents. The results indicate that the initial pavement condition improved from a PCI of 52 and IRI of 6.8 m/km to a PCI of 84 and IRI of 3.1 m/km after preservation. The E-Catalog procurement mechanism reduced unit costs by 3.6–12.9% and shortened the procurement duration from 40 days to 12 days. Nevertheless, implementation remains constrained by the limited availability of suppliers and specific construction items within the electronic catalog.
E-Catalog, Construction Procurement, Pavement Condition, Procurement Efficiency, Road Preservation.
Copyright (c) 2026 Priyo Supeno, Rezi Munizar, Mekarria Pangaribuan (Author) https://creativecommons.org/licenses/by/4.0
Redesign of the Earthquake-Resistant Upper Structure of an Apartment Building Based on SNI 1726:2019 in the City of Semarang
Indonesia lies within a region of high seismic activity; therefore, the structural design of buildings must adequately account for earthquake effects. The apartment building located in the city of Semarang is a four-story residential structure constructed in 2023 and originally designed in accordance with SNI 1726:2012 provisions. With the enactment of SNI 1726:2019 as the latest regulatory standard, a structural reassessment and redesign of the building’s superstructure are required to ensure its safety level and structural performance under seismic loads. This study aims to redesign the superstructure of the apartment building, including beams, columns, and slabs, using the Special Moment Resisting Frame System (SMRF) in compliance with SNI 1726:2019, SNI 1727:2018, and SNI 2847:2019. Structural analysis was conducted using both the equivalent static method and response spectrum analysis with the aid of ETABS software. Seismic parameters were determined based on the site conditions, assuming a soft soil classification (Site Class SE). The design results indicate that the building structure satisfies seismic resistance requirements, as evidenced by the magnitude of the design earthquake forces, inter-story drift limits, and the ductility provisions of the SMRF system. The redesigned dimensions and reinforcement detailing of structural elements—columns, beams, and slabs have been adjusted to fulfill the strong column–weak beam principle. Therefore, the redesigned superstructure of the apartment building, based on SNI 1726:2019, is deemed safe and capable of enhancing structural performance against earthquake effects.
Earthquake-resistant building, ETABS, structural redesign, SNI 1726:2019, SRPMK.
Copyright (c) 2026 Aldino Daffa Cahya Pratama, Muhammad Naufal ArRasyid (Author) https://creativecommons.org/licenses/by/4.0
Synthesis of Chitosan from Shrimp Shell Waste and Its Use as a Natural Preservative for Beef
The utilization of shrimp shell waste as a source of chitosan represents a sustainable approach to developing bio-based materials while increasing the economic value of fisheries by-products. This study aimed to synthesize chitosan from shrimp shells (Litopenaeus vannamei) and evaluate its effectiveness as a natural preservative for beef. Chitosan was synthesized through deproteinization using 1 N NaOH, demineralization using 1 N HCl, and deacetylation using 50% NaOH. X-ray diffraction (XRD) analysis revealed six diffraction peaks with a dominant peak at 2θ = 19.042° and crystallite sizes ranging from 4.36 to 4.57 nm, indicating a monoclinic crystal structure. Fourier Transform Infrared Spectroscopy (FTIR) confirmed the presence of characteristic chitosan functional groups, including hydroxyl, amine, amide, and β-(1→4)-glycosidic bonds. Preservation performance was evaluated by immersing beef samples in 1% chitosan solution for 0, 15, 30, 45, and 60 minutes, followed by storage at room temperature for five days. The results showed that immersion treatments of 45–60 minutes were most effective in maintaining texture, odor quality, and pH stability. These findings demonstrate the potential of shrimp shell-derived chitosan as a safe, environmentally friendly, and economically valuable natural preservative.
Beef, Chitosan, FTIR, Shrimp Shell Waste, XRD.
Copyright (c) 2026 Fitri Endriyani, Rahmat Hidayat, Yenni Darvina, Fadhila Ulfa Jhora (Author) https://creativecommons.org/licenses/by/4.0