Teknisia

Structural evaluation and analysis of existing house renovation into shophouse based on Building Information Modeling

Ahmad Yudi — 2024-09-30

Indonesia's population and economic growth must be supported by adequate facilities and infrastructure, including residences and business premises. Renovating residential houses into shophouses offers an effective way to optimize land use and reduce construction costs. A thorough evaluation of existing structural elements is critical to determining which components can be retained, alongside accurate cost and scheduling assessments to ensure smooth renovation. This research utilizes Building Information Modeling (BIM) to integrate structural, architectural, and MEP work, as well as to streamline scheduling and cost estimation. ETABS is employed for structural design, while Autodesk Revit and Navisworks are used for cost and schedule planning. The assessment follows ASCE 41-17 guidelines to evaluate existing structures, and SNI 1726:2019 and SNI 2847:2019 standards for retrofitting and designing new structures. The evaluation reveals deficiencies in global strength and component ductility, necessitating structural retrofits using concrete jacketing. This study not only addresses the renovation of a residential house into a shophouse but also contributes to broader research in construction. The estimated cost for the structural renovation is Rp. 159,692,607.93, and the duration is projected at 58 days, with 11 days for demolition and 47 days for upper structure construction.

Finite element modelling of soil nailing inclination effect on slope stability: Cibeureum slope case study

Azmi Aufa Iftikhar — 2024-09-30

On November 21, 2022, a 5.6 magnitude earthquake caused a landslide on one of the slopes in Cibeureum, Cianjur district. To repair the slope, reinforcement is necessary to achieve stability values that can withstand future earthquakes. One method for enhancing slope stability is soil nailing. Various soil nailing installation angles were analyzed to find the optimal design for the Cibeureum slope. Using the Plaxis 2D V20 program, the safety factor of the original slope without an earthquake was found to be 1.62. Increasing the installation angle of the soil nails from 10°, 15°, to 20° improved the safety factor, but the increase was not significant because the initial installation point was far from the slip line, requiring a nail length of 50 meters. The best configuration, yielding the highest safety value, was achieved with a modified slope angle of 19° and soil nails with a 50 m length installed at a 20° angle. This configuration produced a safety factor of 2.55 without an earthquake and 1.102 with an earthquake, as calculated using the Plaxis 2D V20 program.

Development of work safety procedures for PCI Girder installation using interactive analysis models

Chairul Ahmad — 2024-09-30

As part of the government's infrastructure acceleration initiative, toll road construction has become a key focus to enhance regional development and connectivity. However, such projects, particularly those involving the installation of precast concrete girders, carry significant risks of workplace accidents. Between 2017 and 2021, six accidents related to girder erection occurred during toll road construction projects. This study aims to develop work safety procedures for the installation of Type I precast concrete girders in the Bakauheni–Sidomulyo toll road project. The proposed safety procedures, presented as a flow chart, are based on national and international safety standards, providing a clear and sequential overview of the process to ensure better understanding and risk mitigation. The study uses the Interactive Analysis Model for data analysis, encompassing Data Collection, Data Reduction, Data Presentation, and Conclusion Drawing, where data collection and analysis are conducted in an iterative and simultaneous manner. The results, validated by site engineers and safety officers both within and outside the project, identified 62 potential risks stemming from unsafe conditions and provided 85 safety recommendations. These findings offer practical guidance for contractors to minimize the risk of accidents during the PCI girder erection process.

Effect of coconut shell ash substitution on compressive strength, wear resistance and water absorption in paving blocks

Khairul Nur Ihfansyah — 2024-09-30

Waste refers to leftover material generated from production processes, industrial activities, or other human activities, often considered discarded due to its lack of economic value. Coconut shell waste is one such material that has not been optimally utilized, and it often accumulates without adequate disposal. However, coconut shell ash, which contains silica, can potentially enhance the compressive strength of paving blocks. This study investigates the effect of coconut shell ash substitution on the compressive strength, wear resistance, and water absorption of paving blocks. The tests were conducted in accordance with SNI-03-0691-1996 standards, including compressive strength, wear resistance, and water absorption tests. Coconut shell ash was substituted at percentages of 5.5%, 7.5%, 9.5%, 11.5%, and 13.5% by weight of cement. The paving blocks were tested at 28 days. The mixture used a 1:3 ratio of cement to sand, with the sand comprising equal parts Merapi and Progo River sand to balance their different grain characteristics—Merapi sand being angular and sharp, and Progo River sand being fine and round. The compressive strength, wear resistance, and water absorption of normal paving blocks were found to be 36.925 MPa, 0.085 mm/min, and 2.132%, respectively. The highest optimal performance was achieved at 9.5% coconut shell ash substitution, yielding a compressive strength of 40.450 MPa, wear resistance of 0.086 mm/min, and water absorption of 2.349%, meeting the quality category A standard for roads.

Performance of infiltration wells in commercial building along the Kaliurang Road, Yogyakarta, between km 12 – 13 in 2017

Sri Amini Yuni Astuti — 2024-09-30

Previous studies have shown that incorporating infiltration wells into drainage systems can significantly reduce surface runoff. However, the actual effectiveness of these wells in absorbing rainfall remains uncertain. This article evaluates the performance of infiltration wells installed at commercial buildings along Kaliurang Road (km 12–13) in 2017. Precipitation data was collected from the nearest weather stations: Kemput, Beran, and Bronggang. The design of the infiltration wells followed the Sunjoto technique, utilizing rainfall data from 2001 to 2020 to determine the rainfall intensity for a 5-year return period. To assess the wells' efficiency, daily rainfall data was converted to hourly data using Tadashi Tanimoto's method. The flow rate from rainfall on the roof was compared with the capacity of the infiltration wells. In 2017, the wells' capacity exceeded the flow rate on 363 out of 365 days, demonstrating an exceptionally high-performance rate of 99.45%. On September 28 and November 28, 2017, however, the wells were unable to handle the rainfall due to insufficient capacity.

Time and cost performance analysis: earned value management method on HPK Project Using Mobox

Vegit Risana Hughes — 2024-09-30

Conventional construction methods have proven inadequate for meeting the accelerated development needs of IKN, highlighting the necessity for innovative approaches to expedite construction. Additionally, challenges related to material supply further exacerbate the situation. The Mobox method emerges as a promising alternative, offering potential to streamline project completion. This study compares time performance between conventional concrete methods, which typically require 7 months, and the Mobox method, which achieves the same in 4 months. The aim is to evaluate whether time and cost performance align with the project owner's expectations, using the Earned Value Management (EVM) method for a 4-storey building project utilizing Mobox modular construction. At week 16, the project’s time performance met expectations, as evidenced by a Schedule Variance (SV) of zero and a Schedule Performance Index (SPI) of 1. Cost performance also exceeded expectations, with a positive Cost Variance (CV) of Rp 11,784,790,045.29 and a Cost Performance Index (CPI) of 1.023, indicating cost efficiency. The Mobox method, coupled with the EVM approach, proves to be an effective and efficient alternative for construction projects, demonstrating the capability to complete projects on time and within budget while maintaining quality.