Karena kekuatan tekannya yang tinggi, beton berperan sebagai material kunci dalam konstruksi kontemporer, kemudahan pembentukan, dan ketahanan terhadap cuaca. Salah satu faktor penting yang memengaruhi kualitas beton adalah ukuran butir agregat halus (pasir). Studi ini menganalisis pengaruh variasi ukuran partikel pasir terhadap kekuatan tekan beton mutu K-150 sesuai dengan SNI 03-2834-2000. Gradasi pasir yang digunakan meliputi No. 4 (0,75 mm), No. 8 (2,36 mm), dan No. 16 (1,18 mm) yang lolos saringan. Spesimen uji silinder (ø150 × 300 mm) dibuat dengan 3 sampel masing-masing dan diawetkan selama 28 hari. Hasil uji menunjukkan bahwa pasir yang lebih halus cenderung meningkatkan kekuatan tekan; Nilai rata-rata tertinggi diperoleh untuk pasir No. 16 sebesar ≈10,45 MPa, diikuti oleh No. 8 ≈8,15 MPa dan No. 4 ≈6,74 MPa. Semua nilai ini berada di bawah target kualitas K-150 (≈14,7 MPa), yang sesuai dengan beban maksimum sekitar 218 kN pada penampang silinder dengan diameter ø150 mm. Temuan ini menunjukkan perlunya peninjauan proporsi campuran dan pengendalian kualitas material jika K-150 ingin dicapai.
The City of Semarang has four drainage systems, one of which is the East Semarang Drainage System. This coastal area is frequently affected by river flooding and tidal flooding (rob). These events cause significant material losses to local communities, as residential areas and road access are inundated by tidal waters. Climate change is one of the contributing factors to these flood events, while changes in land cover have further increased surface runoff, thereby exacerbating flooding conditions. The purpose of this study is to develop a flood characteristic map based on inundation extent, flood depth, and flow velocity. The objectives are to determine flood hazard levels, flood vulnerability, and flood risk characteristics within the East Semarang Drainage System based on inundation area, depth, and flow velocity. Additionally, the study analyzes flood discharges for return periods of 5 years, 50 years, and 100 years. Hydrological modeling was conducted using HEC-HMS software, while hydraulic modeling was performed using HEC-RAS 2D. Following the simulation, the resulting inundation extents and flood characteristics were mapped to produce flood inundation maps. The inundated area affected under the Q25-year discharge scenario covers 2,290.93 hectares, including the sub-districts of Genuk, Gayamsari, and Pedurungan.
Clean water supply systems play a vital role in supporting public health and improving community welfare, requiring reliable and efficient distribution networks to meet increasing demand. In Sukoharjo Regency, the Wosusokas Regional Drinking Water Supply System includes the Bugel Reservoir as one of its main supply facilities, whose optimal utilization depends on the performance of the main distribution network. This study aims to plan the Main Distribution Network (MDN) by evaluating projected water demand, topographic conditions, and hydraulic performance through population-based demand analysis, network configuration planning, and hydraulic simulation using EPANET 2.2. The results show that total water demand in the planning year reaches approximately 49.18 L/s and is projected to be fully utilized by 2031. The system is divided into six District Meter Areas (DMAs) with peak demands ranging from 4.99 L/s to 12.62 L/s, indicating the need for additional raw water sources in future periods. A branched network configuration with pipe diameters ranging from 6 to 12 inches was applied to accommodate elevation differences. Simulation results indicate that pressure and headloss values comply with allowable design criteria, confirming the technical feasibility of the proposed distribution network.
Penelitian ini dilakukan untuk mengkaji sejauh mana keselamatan dan kesehatan kerja (K3) serta motivasi berpengaruh terhadap kinerja tenaga kerja pada proyek pembangunan Kantor Alfamart di Palangka Raya. Penelitian menggunakan pendekatan kuantitatif dengan metode survei melalui kuesioner yang disebarkan kepada 54 responden. Jumlah sampel tersebut ditentukan dengan rumus Slovin dari total populasi sebanyak 117 pekerja. Data yang terkumpul dianalisis menggunakan regresi linier berganda guna mengetahui pengaruh variabel bebas terhadap variabel terikat baik secara parsial maupun simultan. Temuan penelitian memperlihatkan bahwa penerapan K3 berpengaruh positif dan signifikan terhadap kinerja, artinya semakin optimal penerapan aspek keselamatan dan kesehatan kerja, semakin tinggi pula produktivitas tenaga kerja. Selain itu, motivasi juga terbukti memberikan pengaruh positif dan signifikan, di mana dorongan dari dalam diri maupun dari luar mampu meningkatkan rasa tanggung jawab, semangat, dan pencapaian target. Secara bersama-sama, K3 dan motivasi memberikan kontribusi yang besar dalam peningkatan kinerja tenaga kerja di proyek konstruksi. Oleh karena itu, dapat disimpulkan bahwa penerapan K3 secara maksimal dan peningkatan motivasi kerja merupakan faktor penting untuk menciptakan kondisi kerja yang aman, nyaman, serta produktif.
The rapid growth of residential developments and infrastructure in Semarang City has driven an increasing demand for efficient and environmentally sustainable construction materials, one of which is paving blocks. This study aims to evaluate the utilization of waste porcelain fragments from discarded toilet fixtures as a partial substitute for fine aggregate in paving block production. The methodology employed includes a job mix design with variations in porcelain content of 0%, 1%, 2%, and 3% by total mixture weight. Laboratory tests were conducted to assess the physical and mechanical properties of the paving blocks, including compressive strength, water absorption, density, and porosity. The results indicate that the addition of 3% porcelain produced the lowest water absorption (7.85%) and the smallest porosity (52.83%), suggesting enhanced water resistance. However, the highest compressive strength was achieved with a 1% porcelain mixture, reaching 299.32 kg/cm². The 3% mixture is considered the most balanced composition, as it provides good performance in terms of water resistance and material structure, although it does not yield the highest compressive strength. Overall, the findings demonstrate the potential of porcelain waste as an eco-friendly supplementary material in paving block manufacturing.
