Jurnal Spesialis Teknik Sipil (JSpTS)

Study on Factors Causing Delays in Completion of Building Construction Work at Lamongan Islamic University

Bobby Damara — 2024-10-17

Schedule delays or increased construction calendar periods are problems that are often encountered in construction project work and can be caused by several factors including managerial factors, implementation methods, work environment and so on, during the construction of buildings at the Islamic University of Lamongan in 2015-2018 there were delays in several buildings or infrastructure built by the university in this study the researchers made efforts to obtain or find out the main supporting factors that influence delays by means of a survey distributing questionnaires to parties with a direct interest in construction project work. The ranking method is used to determine the ranking of respondents which can later be used as a reference as to why the construction of campus buildings is delayed, Data analysis in this study uses multiple linear regression analysis stepwise method based on the results of the analysis of variable X7 (implementation method) is the most dominant factor in time delays obtained coefficient value 0, 924 or 92.4% with a multiple linear regression equation Y = 0.962 + 0.924 (X7) and the results of the β coefficient value, obtained the following ranking The implementation method factor (X7) with a β coefficient value of 0.924, financial factors (X5) with a β coefficient value of 0.171, managerial factors (X8) with a β coefficient value of 0.040. Design factor (X2) with a β coefficient value of 0.031, Labor factor (X1) with a β coefficient value of -0.017, Work environment factor (X3) with a β coefficient value of -0.063. Material / material factor (X4) with a β coefficient value of -0.064, Equipment factor (X6) with a β coefficient value of -0.136, Based on the results of the analysis obtained for construction service providers who carry out development work, must apply good and efficient implementation methods in all stages of work.

Analysis of Prediction of Highway Violence Conditions using the IRI Application for Road Handling (Case Study: City National Road Section City National Road Section, Gresik-Sadang)

Desmin Kogoya — 2024-10-17

Road pavement conditions will overcome the decline in service levels over time. The decline in the level of road services is characterized by the occurrence of damage to the structure of the pavement layer of the road and left in a long period of time it will be able to renew the level of the layer of security that can increase security, comfort, and smoothness in crossing. The purpose of this study is to analyze the influence of traffic, pavement structure and CBR on the value of road IRI and estimation of road pavement conditions in the next 10 years. The data used in this research are traffic load, CBR, rainfall and road pavement structure. The analysis was carried out using a method developed by IRI (International Roughness Index) to predict road conditions. Data collection was carried out by surveying road damage using the ROADROID application and (RCI) the Road Condition Index as preliminary data. This research will be applied to data collected from the national road network in East Java province, specifically the Bts national road section. Gresik City - Sadang. To facilitate analysis, the road segment is divided into 3 segments with the length of each km segment starting from Km 20 to Km 40. The results of data analysis show an increase in traffic load of 31% will result in an increase in IRI value of 0.061 m / km per year, a structural value of 11.32% resulting in an increase in IRI of 0.034 m / km per growth, based on a CBR of 38% resulting in an increase IRI value of 0.017 m / km per year. The predicted results of road pavement conditions on Km 40, 20 and 20 sections are minor damaged roads, for Km 20, 40 routine maintenance sections.

Implementation Of The Last Planner System (On The Construction Project Of Al-Falah Junior High School)

Ahmad Fadhil Ferdiandika — 2024-10-17

Currently, the construction sector is adopting the theory of production in the manufacturing industry, known as lean construction, to reduce waste and increase value. Last Planner System (LPS) has not been widely used and has good potential because the advantage of LPS is to identify a job along with obstacles to improve performance in a construction project. In the construction of Junior High School (SMP) Al-Falah, it has work obstacles due to erratic weather so that the project is delayed, the author conducts a field survey to analyze the actual progress in the field, LPS has work indicators / work flow to measure the extent to which work indicators can be realized properly, the LPS work flow are Master Plan, Phase & Pull Planning, Lookahead Planning, Constraints Analysis, Shielding Production, and Percent Plan Complete (PPC) as a standard for measuring whether project productivity is realized properly or not. In this study, the results of the implementation using LPS on the Al-Falah Junior High School construction project show that the lowest PPC can be seen in week 7, which is 0% because there is no work achievement so that the work is delayed, while in week 16 it can be seen that PPC has increased dramatically to 96%. Then after averaging the PPC of 51% which means that LPS has not been able to increase the reliability of planning above 70%, (Ballard, 2000).

Geotechnical Stability Assessment and Soil Improvement Recommendations with Soil Grouting and Drainage Tunnels (Case Study: Displacement of Transmission Tower Foundation Soil Retaining Wall)

Heri Khoeri — 2024-10-17

The detection of a retaining wall displacement in early 2023 at one of the DD6+12 transmission tower sites raised concerns about the tower's stability, potentially leading to structural failure. A comprehensive assessment was conducted on the tower's verticality, retaining wall displacement, subsurface conditions, and soil properties around the tower area. The assessment results revealed a linear inclination of the transmission tower from the base to the top, with a deflection at the top of approximately ±20 cm to the south and ±7 cm to the west. With this condition, some structural elements reached a stress-to-permitted stress ratio of 0.91. Although still within allowable limits, without soil stabilization, it is at risk of structural failure. GPR scan results showed differences in foundation dimensions compared to the as-built drawings and identified cavities filled with water beneath the ground surface due to poor drainage, resulting in a safety factor of 1.088, whereas the required safety factor is 1.5. This condition caused the retaining wall displacement. Recommendations including constructing drainage tunnels upstream, soil grouting, installing wheep holes in the retaining walls, and adding secant piles would increase the safety factor to 1.988.

Optimization of Water Utilization of Reservoir System Semi-Cascade System of Pacal Reservoir and Gongseng Reservoir by Using a Linear Program

Nia Agustina — 2024-10-17

Pacal Reservoir and Gongseng Reservoir are reservoirs located in Temayang District, Bojonegoro Regency, East Java. These two reservoirs irrigate the Pacal Irrigation Area with an area of 7.049 Ha with other functions of the Gongseng Reservoir as a raw water provider, potentially as a power plant, and able to reduce flooding. This study aims to determine the optimization of water utilization of Pacal Reservoir and Gongseng Reservoir to meet the needs of irrigation water and raw water in the next 10 years. Optimization is carried out using a linear program with Microsoft Excel Solver Add-ins to get the optimal reservoir water utilization to meet the needs by maximizing the profit of agricultural products in irrigation. From the results of the analysis of reservoir water utilization that has been carried out for the next 10 years, it is found that the amount of irrigation water needed for the existing cropping pattern is 2,89 m3/det, for alternative cropping pattern 2 is 3,94 m3/det, and for alternative 3 is 2,51 m3/det. The raw water demand for Temayang, Sukosewu, Sugihwaras, and Kedungadem sub-districts is 0,48 m3/det. The amount of discharge to rotate the turbine is 1,22 m3/det with the amount of energy generated is 59,91 MWh. With the availability of discharge in both reservoirs, both reservoirs are able to meet the needs of irrigation, raw water, and MHP for the next 10 years with the most optimum cropping pattern based on maximum profit is in alternative 2 (Paddy-Paddy-Palawija) with a total profit of Rp 601.683.497.035. In addition, the Gongseng Reservoir is able to reduce flooding by 60,87% at Q25; 60,58% at Q50; 60,41% at Q100; 58,64% at Q1000 and 45,94% at QPMF.