REKAYASA: Jurnal Ilmiah Fakultas Teknik Universitas Lampung

Analisis Kelayakan Ekonomi Investasi Pembangunan Embung Pulung Kencana di Kabupaten Tulang Bawang Barat

Elsa Permata Gusti — 2024-12-29

Pulung Kencana Village is one of the villages located in West Tulang Bawang Regency. The location for the construction of the reservoir itself was planned on land that was not utilized optimally. The aim of this research was to determine the costs, benefits and investment feasibility value obtained from the construction of a reservoir in Pulung Kencana Village. This research is a case study that aired at analyzing the economic feasibility of investing in the construction of a reservoir based on the costs used and the economic benefits of the surrounding community from the construction of the Pulung Kencana Embung, Then the calculation of the costs and benefits will be processed to determine the feasibility of building the reservoir.The research data were analyzed using four methods, namely Net Present Value (NPV), Internal Rate of Return (IRR), Benefit Cost Ratio (BCR), and Payback Period (PP). The results of the analysis that the benefits of building embungs can be seen from three crucial sectors (agriculture, fisheries and tourism) and are considered feasible to continue to the next stage, because all scenarios meet the existing criteria. The best condition is in the eleventh scenario with calculations using an interest rate of 10% and the assumption that the annual income generated is 110%.

Pengaruh Abu Ketel Sebagai Bahan Pengganti Sebagian Semen Dalam Campuran Beton Normal Terhadap Kuat Tekan

Habib Ilham Abdullah — 2024-12-30

Limbah abu ketel yang dihasilkan dari proses pengolahan kelapa sawit sering kali tidak dimanfaatkan dan berpotensi mencemari lingkungan sekitarnya. Abu ketel berasal dari pembakaran tempurung kelapa sawit pada suhu antara 700?C hingga 800?C. Oleh karena itu, penting untuk memanfaatkan limbah abu ketel ini, khususnya sebagai campuran dalam beton. Penelitian ini bertujuan untuk menganalisis pengaruh penggunaan abu ketel terhadap waktu pengikatan semen dan kekuatan tekan beton melalui eksperimen di laboratorium. Variabel yang diteliti mencakup persentase penggantian abu ketel terhadap sebagian semen (0%, 5%, 10%, 15%, dan 20%). Sampel uji berupa pasta beton dan beton kubus dengan dimensi 15x15x15 cm pada umur 28 hari. Hasil eksperimen menunjukkan bahwa penggunaan abu ketel dapat mempercepat proses pengikatan semen dan menghasilkan slump yang lebih rendah. Semakin tinggi persentase abu ketel, semakin rendah slumpnya. Kadar optimal substitusi abu ketel pada beton kubus 28 hari adalah 5%, dengan kekuatan tekan 29,47 Mpa. Selain itu, penggunaan abu ketel pada persentase lainnya (5%, 10%, dan 15%) cenderung dapat mempertahankan atau bahkan meningkatkan kekuatan tekan beton pada umur 28 hari, dengan persentase 5% menunjukkan hasil yang optimal. Dengan demikian, penggunaan abu ketel dalam beton memberikan dampak positif pada kekuatan tekan beton serta membantu dalam pemanfaatan limbah industri.

Analysis of the Implementation of Time and Cost Control in the Construction of Building C Fkip Phase III, University of Lampung Using the Earned Value Method

Ike Novita Sari — 2025-06-26

Infrastructure is the main support in improving education in Indonesia. University of Lampung carries out routine the constraction and renovation of buildings to support educational facility needs. In order of construction project activities on schedule and on budget, so project control is needed as in construction for building C FKIP Phase 3 University of Lampung of the was carried out using the earned value method. This research aims to analyze cost and time performance by implementing earned value analysis, as well as knowing the variance in the Phase 3 FKIP Building C building project University of Lampung. The data used in this research is secondary data in the form of time scheduling, RAB, plan drawings, and weekly project progress reports. The results of the research show that the planned time for the construction contract for Building C FKIP Phase 3 University of Lampung, is 120 calendar days and this time is by the Estimate at Schedule calculation results in the last week. The estimated total time for project completion is 120 calendar days, which means the project was completed on time and did not experience additional time during construction or it could also be called on schedule. The actual costs incurred by the contractor were 9.56307021468% lower than the planned and the value of the work completed by the contractor.

Penanganan rembesan dan perkuatan tanah menggunakan metode insitu test (pressure meter test) studi kasus : proyek Bendungan Margatig

Nora Anggraini — 2024-12-29

The purpose of this writing is to determine the handling of seepage and soil reinforcement required in the case study of the Margatiga Dam Project, East Lampung. Based on the results of geological investigations, the Margatiga Dam is composed of quarter-old rock layers with a fragment composition in the form of fine sand - gravel, with a hardness level of soft - hard and the need for foundation repairs. Based on the lithological conditions of the Margatiga Dam Extraction Gate foundation and the Spillway building which are composed of relatively deep and quite porous alluvial sand deposits, this causes the curtain grouting results to be ineffective, therefore it is necessary to change the design to control seepage from the Grouting Curtain to the boundary wall. Based on the simulation checks in the Plaxis Software for Seepage and Excavation Staging, processing was carried out using Secant Pile and Soldier Pile with a depth of 30 meters with a stretch of 140 m and overlapping with the left side of the Embankment Curtain Goruting. and the right side 5 m. PMT results in the field show that the maximum stress in the rock layer under the spillway foundation is 0.016 MPa and 0.630 MPa.

Analisis Kinerja Simpang Tak Bersinyal (Studi Kasus Jl. Imam Bonjol – Jl. Pagar Alam)

Sahara Nugra Diani — 2025-06-26

Simpang Jl. Imam Bonjol – Jl. Pagar Alam termasuk simpang tak bersinyal yang sering mengalami kepadatan arus lalu lintas. Pada persimpangan jalan, sering terjadi kemacetan pada waktu-waktu tertentu yaitu pada pagi dan sore hari. Tujuan penelitian untuk mengetahui aru lalu lintas (Q) dan kapasitas simpang (C), menganalisis derajat kejenuhan dan besarnya tundaan, dan mengetahui tingkat pelayanan. Metode yang digunkan untuk menganalisis kinerja ruas jalan pada simpang menggunakan metode Pedoman Kapasitas Jalan Indonesia (PKJI, 2014). Kesimpulannya arus lalu lintas tertinggi sebesar 1881,3 skr/jam dan kapasitas simpang sebesar 3002 skr/jam untuk hari senin dan arus lalu lintas tertinggi sebesar 2122,3 skr/jam dan kapasitas simpang sebesar 2968 skr/jam untuk hari sabtu yang artinya kepadatan pada simpang tersebut sudah ramai dan mengakibatkan sedikit kemacetan pada jam sibuk. Nilai derajat kejenuhan pada hari senin 0,63 dan hari sabtu 0,72 serta tundaan berhenti 11,05 det/skr untuk hari senin dan 12,11 det/skr untuk hari sabtu yang artinya kondisi pada simpang tersebut mulai tidak stabil dan kecepatan menurun. Tundaan yang didapatkan bahwa tingkat pelayanan simpang tak bersinyal pada saat ini berada pada tingkat C yang artinya tingkat pelayanan pada simpang tersebut masih dikategorikan baik karena rentan tundaan antara 11-20 det/skr.

The Deformation of rigid pavement at an early age

Diego Maradona Maharduta Diego — 2024-12-29

Cracks in rigid pavements are common. One of the causes is cracking caused by shrinkage that the concrete is unable to accommodate. When early age shrinkage cannot be accommodated, the risk of performance degradation becomes greater. The purpose of this study is to determine the deformation that occurs on concrete roads in Lampung Province, Indonesia from the time of casting until the concrete is 24 hours old. The research sample is a rigid pavement measuring 5000×4500×300 mm with fs' 4.5 MPa and f "c 25 Mpa which is a real toll road. Curing of concrete is done by covering the concrete with geotextile and moistened every 2 hours since the concrete is 13 hours 30 minutes old. The research methods used are observation and interview. The tool used in the research is Vibration Wired Embedded Strain Gauge (VWESG) and the research was conducted for 24 hours since the concrete was cast. Data analysis in this study uses descriptive analysis of observation and measurement results. The results showed that the deformation of concrete that occurs in rigid pavements in Indonesia from the largest to the smallest in order starting from the middle part, the long side, the short side, then the corner of the segment.