Engineering Headway Vol. 23

Abstract: The Pamukkulu Dam has an intake structure in the form of a tunnel (underground structure) which functions to drain water for irrigation and raw water in Takalar Regency, South Sulawesi Province, Indonesia. This study aims to determine the classification of rock masses, which were carried out based on the Geological Strength Index (GSI) and Japan Society for Civil Engineers (JSCE), to analyze the intake tunnel's excavation method and support system. The research method included surface geological mapping and evaluation of the core drill along the intake tunnel to determine the classification of rock masses along the intake tunnel. Surface geological mapping indicated that the lithologies in the intake tunnel were basalt and breccia. Based on the core drill evaluation results, the rock masses along the tunnel alignment based on the GSI are classified as very good, and the recommended tunnel excavation method is blasting. Based on the JSCE, the rock masses along the tunnel alignment are classified into rock category B. Full-face full excavation is recommended with an advance of 2 m. Based on the JSCE, the recommendation for a support system is a rock bolt with a length of 4 m, spacing of 1.5 m, shotcrete of 10 cm, and lining of 40 cm on the crown and wall.

Abstract: Clay shale is composed of clay, rock, and dust that has undergone a cementation process, has unique characteristics, namely being very hard when dry and very soft when wet. However, due to the exposed layers of clay shale, it also weathering due to continuous contact with air. This causes the failure of structures standing on clay shale. One of the parameters that affect the strength of clay shale is the shear strength parameter which can be carried out through direct shear and uncofined compression strength tests. In this study the addition of water content was applied to determine changes in the shear strength parameters of clay shale. Based on the results of the direct shear and unconfined compression strength test, it was found that with the addition of water content, the shear strength parameter of clay shale decreased. The addition of 100% water content causes the friction angel to be 18.93^o and the cohesion to be 11.95 kPa on the direct shear test. While the results of the unconfined compression strength test showed a decrease of 81.18% at the addition of 75% water content. The decrease in the shear strength parameter is due to the loss of bonds between particles.

Abstract: The construction of high-rise buildings, particularly in major cities in Indonesia, is one of the alternative development approaches undertaken to address land limitations. High-rise construction involves hazardous work due to the unique characteristics and complexities of the work environment, which can potentially lead to accidents. The high incidence of construction accidents is closely related to the parties directly involved in construction projects, commonly referred to as stakeholders. In Indonesia, construction stakeholders include contractors, subcontractors, structural consultants, architectural consultants, owners, and supervising consultants. This study aims to analyze the stakeholders' perceptions and understanding of construction safety risks in high-rise buildings using photographic Q-methodology. Additionally, Kendall's W coefficient, Friedman's χ2, and Kruskal-Wallis analyses are used to measure stakeholders' understanding. Overall, contractors, subcontractors, structural consultants, owners, and supervising consultants demonstrate a moderate level of understanding, while architectural consultants exhibit a lower level of understanding. Based on these findings, the author formulates recommendations to enhance the understanding of all stakeholders regarding construction safety risks in Indonesia. These findings provide valuable insights for stakeholders and policymakers, enabling them to better understand the perceptions and understanding of each stakeholder in construction projects and ultimately improve construction safety performance in Indonesia.

Abstract: This study aims to evaluate the risks that arise in tank operations and design risk mitigation for tank operations. This research uses the Hazard and Operability Study (HAZOP) method, where HAZOP is used to explain each part of the process to determine the risk of tank operations made and the causes and consequences. The data collected includes primary data and secondary data. Primary data is obtained through observation, interviews, and questionnaire survey results. The data sample in this study was carried out on a stockpile tank construction project owned by state-owned PT Pertamina Persero. The results showed that 1) sources of danger classified as extreme were found in the risk of fire, 2) sources of danger classified as extreme were found in the risk of fire, while the source of danger classified as moderate was the queue of tank cars, 3) risk mitigation obtained in this study were 36 mitigations in the process of receiving fuel oil and 35 mitigations in the process of distributing fuel oil, and the impact of risks obtained in this study in the form of fire, material loss, environmental pollution, oil contamination, explosion, tank leakage, sparks, lightning, overpressure, queuing mobile tanks

Abstract: A humanized pedestrian facility is built by considering the size and dimensions based on the human scale. Several studies have shown that many pedestrian facilities built in various cities in Indonesia have not been able to meet the needs of the users. This study was conducted to review the suitability of pedestrian facilities in Rantepao against existing guidelines. The research method was carried out by collecting data on pedestrian crossings and dimensions of the constructed facilities. The data was then analyzed and compared against the Pd 03-2017-B Pedestrian Facilities Planning Guidelines. The results showed that of the 20 sidewalks reviewed, only 30% could be passed by 2 pedestrians while holding hands or passing each other. While the use of zebra crossing for crossing facilities is appropriate. The transverse slope of the sidewalks all meets the requirements. The Blind cane users and crutch users can pass through the sidewalk, but wheelchair users cannot pass through safely.

Abstract: Natural gas is selected as transition energy to achieve net zero emissions. Gas pipeline construction is developed in accordance with Sustainable Development Goals on Industry, Innovation & Infrastructure, Clean & Affordable Energy, and Climate Action. The potential risk of the heat transfer process from the pipeline to the ground surface temperature can create a potential hazard that can cause pain/injury to human skin if it exceeds the pain threshold temperature. This study aims to investigate the best method for risk mitigation of heat transfer from gas pipelines to the ground surface, through alternative solutions such as burial deepening options, insulation options, or air cooler at well site options. These options are studied as part of the risk mitigation strategy for the buried high-temperature gas pipeline construction. These risk mitigation options consider technical and economic feasibility studies at the conceptual stage presented in this study to identify the best option to mitigate the potential injury risk to humans. The result with a buried insulated pipeline is the best option for controlling heat transfer compared to the air cooler option. The constructability of burial deepening up to 8 m is not feasible, especially the 6m depth of the groundwater table observed.

Abstract: Inside INarisk map, the National Disaster Management Agency (BNPB) shows that the coastal area of Barru has a moderate level of vulnerability to tsunami waves. Strategic steps which need to be taken are efforts to avoid or reduce casualties and property as well as damage to city infrastructure. The aim of the study is to determine a tsunami disaster management strategy based on the aspirations and expectations of the community. Primary data is needed in the form of the community level of understanding of the tsunami as well as data on the availability of supporting infrastructure and facilities for tsunami disaster mitigation. The secondary data needed is in the form of planning documents related to disaster management. In order to find out the community's knowledge and expectations of the tsunami, an IPA (importance performance analysis) analysis was used which linked to urban conditions related to the variables of the tsunami disaster. This study found that level of public understanding of the tsunami disaster and its countermeasures was still limited, therefore educational efforts are needed from each element. In general, the condition of the study areas did not yet have adequate tsunami mitigation facilities and infrastructures. Some of the community's preferences regarding the tsunami include the need for the availability of tsunami early warning, hospitals, roads to evacuation sites, coastal embankment infrastructure, and disaster evacuation sites.