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This study aims to design and implement a damage analysis system for concrete surfaces by utilizing digital image processing based on the Canny edge detection method. The developed system allows users to upload images of concrete surfaces, which are then processed through several stages: conversion to grayscale, transformation to binary images, and crack edge detection using the Canny operator. This process aims to automatically detect crack patterns on the concrete surface. The detection results, represented as edge lines, are used to calculate the percentage of the damaged area. Based on this percentage value, the system automatically classifies the damage level into light, moderate, or severe categories. System testing shows that the Canny method can accurately identify crack patterns, with sufficient detection levels to be used in monitoring the condition of concrete surfaces. The analysis results are then presented in both visual and numerical forms, providing valuable information for assessing the structural condition of concrete. Thus, this system can serve as an efficient and effective tool for early detection of structural damage in concrete infrastructure, ultimately supporting better maintenance and repair efforts.

This study aims to determine the relationship between conflict management, occupational safety and health (OHS), and work motivation towards increasing employee productivity at PT. Ratna Beton Giriwoyo. The background of this study is based on the importance of human resource management as a company's main asset in achieving optimal productivity targets, especially in the construction industry sector which has its own challenges in creating a safe and productive work environment. This study uses a quantitative approach with data collection techniques through distributing questionnaires to all company employees as respondents. The data obtained are then analyzed statistically to determine the effect of each variable on employee work productivity. The results show that conflict management has a significant relationship with employee productivity. Properly managed conflict not only avoids a decline in performance but can also increase morale and cooperation between employees. In addition, the implementation of good occupational safety and health (OHS) contributes to a sense of security and comfort at work, thereby reducing workplace accidents and increasing employee focus and work efficiency. Work motivation has also been shown to have an important role in encouraging employees to achieve predetermined performance targets. These three variables, both partially and simultaneously, have a significant effect on employee work productivity. These findings suggest that an integrated approach to conflict management, OSH implementation, and increased work motivation can be an effective strategy for improving company performance. This research is expected to provide practical contributions to the management of PT. Ratna Beton Giriwoyo in formulating human resource development policies, as well as serve as an academic reference for researchers and students interested in human resource management, particularly in the construction sector.

Wijaya Karya Beton Deli Serdang Branch Office is a company in the precast concrete industry. The phenomenon in the company is that employee performance is declining because the workload received by employees is too heavy and employee turnover is quite high. This study uses a quantitative descriptive research type. The population in the study was 93 employees with a sampling technique using saturated samples so that 93 samples were obtained. Simultaneously, there is a significant influence between the variables of workload and employee turnover on the performance of employees of PT. Wijaya Karya Beton Deli Serdang Branch Office. While partially, it was found that the workload variable did not have a significant effect on the performance of employees of PT. Wijaya Karya Beton Deli Serdang Branch Office. Partially, it was found that the employee turnover variable did not have a significant effect on the performance of employees of PT. Wijaya Karya Beton Deli Serdang Branch Office.

The durability of Self-Compacting Concrete (SCC) containing fly ash and Sika Viscocrete can be affected by exposure to seawater. This research investigates how seawater curing impacts the compressive strength of SCC modified with varying fly ash content and Sika Viscocrete admixture. The concrete mixtures were designed with 0% and 30% fly ash by cement weight and a constant 1% dosage of Sika Viscocrete. Compressive strength tests were conducted at 7, 14, and 28 days. The findings indicate that seawater curing has a notable effect on compressive strength, producing generally higher strength values than those cured in freshwater. Under freshwater conditions, strength increased steadily at 14 and 28 days, peaking at 54.1 MPa with 30% fly ash at 28 days. Conversely, the highest strength under seawater curing was achieved earlier, at 7 days, also with 30% fly ash, reaching 56.1 MPa. Overall, the optimum compressive strength was attained with a 30% fly ash mixture cured in seawater, suggesting this method enhances early-age strength in SCC.

This study aims to optimize the productivity of Crawler Crane heavy equipment in lifting precast concrete structural elements at PT Wijaya Karya Beton Tbk. The method used is a descriptive qualitative approach with data collection through direct observation in the field. The data is based on the equipment's operating cycle time and work efficiency. The results of the study show that the Crawler Crane heavy equipment used by PT Wijaya Karya Beton Tbk. produces a productivity of 20 tons/hour or 160 tons/day for 8 hours with the need for 2 units of crawler crane heavy equipment, resulting in a work efficiency of 80%. So the productivity results from the calculation have been optimal, so it is hoped that the results of this study can be a reference in the management of heavy equipment, especially Crawler Cranes in construction work at the Company PT. Wijaya Karya Beton Tbk.

This study analyzes the flexural behavior of reinforced geopolymer concrete beams through numerical simulation based on the Finite Element Method (FEM) using ANSYS software, comparing it with conventional reinforced concrete beams. The background of this research focuses on the need for environmentally friendly construction materials, considering the high CO₂ emissions from Portland cement production. The numerical model was developed based on parameters and loading schemes from previous experimental studies, utilizing SOLID65 elements for concrete, LINK180 for steel reinforcement, and SOLID185 for supports. Simulation results show that the flexural behaviour of geopolymer beams is comparable to conventional beams in terms of load-deflection relationships, flexural capacity, and crack patterns, with deviations from experimental data generally below 10%. The patterns and propagation of cracks also exhibited similarities, starting from the tensile zone at mid-span. Furthermore, the analysis demonstrates consistency with the analytical approach based on SNI 2847:2019. This research supports the validity of using geopolymer concrete as a sustainable structural material alternative and shows that the FEM numerical method is effective in evaluating the flexural performance of concrete structural elements.

Material handling is a term for transportation or transport activities carried out by industrial companies, which involve moving raw materials, semi-finished goods or finished goods from one location to another predetermined location. Apart from that, material handling is also important in quality control, where 3-5% of damaged goods are caused by material handling. The aim of this research is to identify and redesign the layout conditions of concrete production facilities at PT. XYZ. The method of this research is the Activity Relationship Chart (ARC), Activity Relationship Daigram (ARD) and Total Closeness Rating (TCR) methods. In the current layout conditions, the sand warehouse and crushed stone warehouse work stations should be close to the two hoppers, namely the batching plant hopper and the asphalt mixing plant hopper, but in the actual conditions these two work stations are not close to each other. In the new facility layout there are changes and relocation of work stations based on the degree of proximity. Future research is expected to consider the amount of time generated during the material handling process and also consider cost aspects during the process of designing changes to the facility layout.

This study aims to analyze the effect of high-lob technique on petanque sport pointing using a concrete field surface. The method used is descriptive research with implementation at the Petanque Laboratory of Surabaya State University. The subjects of the study were five Unesa petanque athletes who were selected based on their technical skills. Data collection techniques include field observation, skill tests, documentation, and data analysis using the Kinovea and Capcut applications. The results showed that at a distance of 6 meters, the release angle was 63.5°, the height was 3.53 m, the rolling distance was 35 cm, and the final result was 8.5 cm. At a distance of 7 meters, the release angle was 63.4°, the height was 4.01 m, the rolling distance was 53 cm, and the final result was 10.4 cm. At a distance of 8 meters, the release angle was 62.3°, the height was 3.99 m, the rolling distance was 59 cm, and the final result was 13.4 cm. Meanwhile, at a distance of 9 meters, the release angle is 60.3°, the height is 4.16 m, the roll is 53 cm, and the final result is 19.2 cm. All parameters have met the effectiveness criteria based on existing references, except for the rolling distances at 7, 8, and 9 meters which exceed the ideal limit. These results imply that adjusting the drop point and increasing the angle and height of the bounce can optimize the results of the high-lob pointing technique.

This research utilizes waste from PLTU Tanjung Jati B Jepara, namely FABA (Fly ash Bottom Ash) as an alternative to fine and coarse aggregate. From this research, the physical properties of faba aggregate can be seen from the results of the faba aggregate sieve analysis test, which obtained a fineness modulus value of 1.74, which is included in the medium aggregate type. The water content of fine aggregate (fly ash) obtained a value of 3.63% and coarse aggregate (bottom ash) obtained a value of 1.5%. The fine aggregate sludge content (fly ash) obtained a value of 0%. The fine aggregate organic substance (fly ash) acquires a reddish brown NaOH color, therefore it must be washed before being used as a concrete mixture. The face dry specific gravity of fine aggregate (fly ash) obtained a value of 2.63 gr/cm2 and coarse aggregate 2.52 gr/cm2. From the data that has been obtained, faba aggregate is considered to have physical properties that meet the requirements for fine aggregate and can be used as a substitute for sand. The results of the final compressive strength of faba concrete and normal concrete at the age of 7 days and 28 days showed that the compressive strength of normal concrete (control) was higher than that of faba concrete. The standard deviation values ​​at the ages of 7 and 28 days are included in perfect working conditions because they have a standard deviation value of less than 3 MPa. From the results of the concrete flexural strength test, only the control concrete was 1;1.5 with a flexural strength of 4.18 MPa, which is close to SNI 2847:2013, namely with a minimum flexural strength of fs = 4.4 MPa. Normal concrete has a higher flexural strength than faba concrete. Based on tests carried out with the planned mix design, the 1:1.5 variation obtained the highest results.

This research is an experimental study on porous concrete and the use of fly ash as a binder for concrete to analyze the effect of compressive strength and porosity. The research method used in this study is the experimental method which is a research method used to find the effect of certain treatments on concrete. In this research, the concrete mix design uses a ratio of gravel and geopolymer paste as a binder, namely 4: 1 and uses a molarity ratio of 10M with differences in grading of coarse aggregate using sieves number 4, 1/2 ", and 3/8". The optimum compressive strength value was obtained in mix design 1 using sieve gradation no.4 which was 4.25 MPa at 28 days old. While the results of the highest porosity value were found in mix design 1 which was 7.15% at 28 days old

This study aims to analyze the implementation of occupational safety and health (OHS) and identify potential hazards and risks of work accidents in the production section of PT. Adhi Persada Beton Batching Plant Kebonarum using the Job Safety Analysis (JSA) method. The study was conducted with a descriptive analytical approach through direct observation. The results of the study showed that the highest risk of accidents occurred in the mobilization of the loader to the hopper, while moderate risks were found in the process of washing the mixer truck, loading concrete, transporting concrete to the casting location, and unloading concrete. The risk controls implemented, such as providing personal protective equipment (PPE), installing safety signs, and routine training, succeeded in reducing the risk level significantly.

One of the impacts of the growth of activities in the transportation sector is the disposal of rubber tire waste. The increasing number of motorized vehicles in society has caused an increase in tire waste. Especially in developing countries, the use of plastic bottles has become an inevitable and unavoidable necessity for society. Inadequate waste management and handling causes negative impacts on the environment, such as hazards to human health, to animal life, soil, water, and air pollution. The purpose of this study was to reduce environmental pollution by testing the compressive strength of concrete made with a mixture of waste. Experiments were conducted in the laboratory with concrete cylinder test objects with a diameter of 150 mm and a height of 300 mm. The proportion of waste mixture, Polyethylene Terephthalate (PET), Rubber Powder, Waste Metalized Film Food Packaging (WMFFP) to fine aggregate was 0%, 5%, and 10%, each variation. The test results showed a compressive strength of 17.62 MPa, 15.29 MPa, and 14.83 MPa at the percentage of waste mixture. From this data, it can be concluded that waste materials can be used as a substitute for sand in concrete.

This project is motivated by the high risk of work accidents in the concrete production process, especially at night when there is poor lighting. Based on observations, there were various significant work incidents, such as injuries from sharp objects and being caught in heavy equipment, which indicate the need for increased risk control. This study aims to design personal protective equipment in the form of an innovative safety helmet using the Job Safety Analysis (JSA) method to improve occupational safety and health (K3) at PT Adhi Persada Beton Batching Plant Kebonarum. The methodology used includes hazard identification, risk analysis, and solution development in the form of designing a safety helmet that is adjusted to the ergonomic needs of workers. This study also includes analysis of work accident data, identification of potential hazards, and evaluation of the effectiveness of existing personal protective equipment. The results of the study indicate that the application of the JSA method can identify risks in a more structured manner, as well as produce recommendations for safety helmet innovations that can improve worker protection against potential hazards.

Penggunaan limbah sebagai bahan substitusi dalam pembuatan beton ramah lingkungan menjadi alternatif yang relevan untuk mengatasi masalah lingkungan dan sumber daya yang semakin menipis. Penelitian ini berfokus pada penggunaan limbah keramik granit, limbah beton, dan cangkang kerang (Grabeka) sebagai pengganti agregat kasar dan halus dalam campuran beton. Pengujian dilakukan untuk menilai kekuatan tekan beton pada umur 28 hari serta analisis biaya dibandingkan dengan beton konvensional. Hasilnya menunjukkan bahwa beton dengan campuran limbah Grabeka mampu mencapai kekuatan tekan optimal sebesar 35,09 Mpa. Selain itu, penggunaan zat aditif Sikament NN mempercepat proses pengerasan, sehingga beton dengan agregat daur ulang menjadi lebih efisien.  

Alternative materials are almost always found in the surrounding nature, therefore innovation in the development of concrete mixture composition must continue to be improved. Natural local materials that are prioritized as a substitute for cement have geopolymer material content and contain silica (Si) and alumina (Al) elements. Clam shells are a new phenomenon in several sea sand quarries in Fakfak Regency. If the shell shell waste is not utilized, it will only create useless piles, as is the case with chicken egg shells, even though this waste has the potential to replace lime in making cement. This study aims to determine the characteristics of the material (clam shell waste, chicken egg shells and sand), and to determine the compressive strength produced in variations in the use of 50% LCK + 50% LCTA, 80% LCK + 20% LCTA and 100% LCTA. The results obtained in this study indicate that clam shells can be used as a component of geopolymer concrete because they have basic elements found in geopolymer materials in the form of SiO2, CaO, Al2O3, Al2O3, and MgO. Meanwhile, in chicken egg shells, the dominant element is only CaO. The dominant variation of shellfish shells using a combination of 80% LCK + 20% LCTA variations has the highest compressive strength value compared to other variations of 14.29 MPa at the age of 28 days, while the variation of 100% chicken egg shells only gets a compressive strength result of 2.20 MPa (age 28 days).

The accounting information system is an evaluation of the application of the accounting information system used in a company to achieve the provision of accurate and effective accounting information in accordance with company objectives. The problem that occurs at PT Varia Usaha Beton is that the ups and downs of profit / loss are not optimal and fluctuate. This study aims to assess how information technology and user technical skills influence the performance of accounting information systems. This study uses descriptive statistical analysis and t-statistical tests, this study found that information technology has a significant and strong influence on the performance of accounting information systems with a path coefficient of 0.60 and p-value <0.1. In contrast, user technical ability shows an insignificant effect on the performance of accounting information systems with a path coefficient of 0.12 and a p-value of 0.23. Overall, information technology is proven to be a key factor in improving the performance of accounting information systems, while the influence of user technical skills requires further research. These results provide important implications for the management of PT Varia Usaha Beton to focus more on developing information technology to improve the performance of accounting information systems.

In regional infrastructure development activities, concrete mix design is a crucial aspect that must be mastered to ensure construction projects are carried out according to plan, meeting cost, quality, and time targets effectively and efficiently, while also being accountable. CV. Marapi Jaya, a construction service company operating in Fakfak Regency, serves as a partner in this Community Service initiative. CV. Marapi Jaya, along with local participants, will be guided and trained through the activity titled Enhancing Technical Skills of Construction Practitioners in Fakfak Regency Through Normal Concrete Design Clinic.The training employs a learning by doing method, focusing on concrete mix design procedures in compliance with SNI (Indonesian National Standard). The materials provided to participants include: an introduction to SNI methods and its design components, calculations for normal concrete mix design, and estimation of material requirements. At the end of the training, participants will receive practical sessions on designing normal concrete mixes and their components.Through this clinic, aligned with SNI standards, the program aims to improve the understanding and skills of participants, including staff from CV. Marapi Jaya and groups of indigenous Papuans engaged in construction services. The outcomes of this community service activity include a publication in an accredited SINTA 6 journal and an article in print or electronic local media documenting the event

The rapid growth of the business world is forcing companies to adopt automation and efficiency to survive and compete. PT. Varia Usaha Beton, a concrete manufacturer, relies heavily on an accounting system for raw material purchasing to ensure efficient operations. The purpose of this research is to evaluate the company's raw material purchasing accounting system, identify problems and recommend improvements. The research method used is descriptive and qualitative with a case study approach. Primary data was obtained through interviews and observations, while secondary data was obtained through company documents. The research results show that the system works well and supports cost control, inventory management and quality monitoring. However, there are several vulnerabilities such as human error, technical issues with the ERP system, and weather-related delays in shipping raw materials. Recommended improvements include improved employee training, optimizing the ERP system, and developing more efficient inventory management. This research provides insights into the importance of evaluating accounting systems to improve the efficiency and effectiveness of business operations. Further research is recommended to conduct comparative analysis with other companies and explore new technologies to increase purchasing management transparency and efficiency

This study aims to redesign the superstructure of the Sambungrejo Bridge in Sidoarjo, which has a span length of 16 meters. The Sambungrejo Bridge originally used WF 700.300.15.28 steel girders and C 300.100.10.16.8 diaphragms,that are susceptible to corrosion, especially during floods. The redesign involves replacing the steel girder with a Prestressed Concrete I Girder (PCI Girder) H-900mm, 170mm thick, produced by WIKA Beton, known for its superior corrosion resistance and construction efficiency. The research methodology includes structural analysis using Robot Structural Analysis Professional (RSAP) software, calculation of prestressing forces, and the design of the prestressing cable layout. The results of this study demonstrate that the use of PCI Girder does not reduce the structural dimensions of the bridge but also proves to be more compatible with the flood water conditions at the site. The total cost required for implementing the new bridge superstructure design is Rp. 4.372.201.

Concrete typically consists of coarse aggregate, fine aggregate, cement, and water. However, cement production generates significant carbon dioxide emissions nearly equivalent to the tons of cement produced. One alternative to conventional concrete, which replaces cement as a binder, is geopolymer concrete. Geopolymer concrete utilizes fly ash or other materials containing silica and alumina as the binder. Unlike cement, which forms a binder through hydration, geopolymer concrete uses a chemical reaction with alkali activators such as Na2SiO3 (sodium silicate) and NaOH (sodium hydroxide). This study investigates the toughness of geopolymer concrete using cylindrical specimens measuring 15 cm x 30 cm with varying Na2SiO3 to NaOH ratios of 1:0.5, 1:1, and 1:1.5, cured at room temperature for 28 days. The study results show that the highest toughness was achieved with a sodium silicate to sodium hydroxide ratio of 1.5, yielding 2.7394 x 105 J/m3. Meanwhile, the toughness values for sodium silicate to sodium hydroxide ratios of 0.5 and 1.0 were 2.3748 x 105 J/m3 and 2.5821 x 105 J/m3, respectively. Thus, increasing the sodium silicate to sodium hydroxide ratio from 0.5 to 1.5 at an activator content of 0.43 affects the toughness of geopolymer concrete.