HIGH STRENGTH CONCRETE USING FLY ASH A CEMENT AND FINE AGGREGATE

At the moment, the cost of concrete is quickly increasing as the cost of cement and aggregates continues to rise. As a result, a replacement for fine aggregate as well as a substitute for cement is required to decrease the cost of concrete production. In general, concrete is composed of cement as a base material that is workable and satisfies specified performance, durability, and strength criteria, aggregate, and water. In the field of engineering constructions, reinforced high-strength concrete has a significant impact on development. Apart from its exceptional strength, this kind of concrete must exhibit workability, minimal shrinkage, release characteristics, and self-compaction. The authors of this research performed a literature review to explore high-quality concrete made using fly ash as a replacement for cement and fine particles. Fly Ash is a waste product or byproduct of the coal-fired power plant's combustion process. Fresh concrete made using fly ash as cement and fine aggregate has an average slump value of 90-200 mm. The compressive strength of concrete made with fly ash ranges between 35 and 60 MPa after a 28-day curing period. The optimal percentage of fly ash in high-strength concrete is between 10% and 30%

Pengaruh Air Laut terhadap Kapasitas Beban pada Balok Beton Bertulang yang Diperkuat GFRP-S dengan Perendaman selama Satu Tahun

The test results on specimens without GFRP-S reinforcement showed that there was a decrease in load capacity for BN0 specimens of 1.383%. Decrease in BN6 test material capacity after soaking sea water for 6 months. Whereas for specimens with reinforcement of GFRP-S shows a decrease in maximum load on BF6 and BF12 specimens against BF0 test objects. The percentage of decrease in loads is 3.898% and 4.285%, respectively. Decreased load capacity of BF12 specimens after 12 months of seawater immersion. This is due to a decrease in the capacity of the bond on the GFRP along with the soaking time, thus accelerating the occurrence of debonding

Sifat Mekanik Beton Serat Ijuk yang Terendam Air Laut

This research aims to determine the value of mechanical properties in fiber fibers which are submerged in seawater and to find out the optimum length of fiber fibers to the mechanical properties of fiber fibers which are submerged in sea water. The method used is an experimental method carried out in the laboratory by varying the length of the fibers, which is 25 mm; 50 mm; 75 mm; and 100 mm with 4% fiber addition. Tests of mechanical properties carried out in the form of compressive strength, split tensile strength, and flexural strength. The results of the research challenge the palm fiber-concrete that the longer the fibers used in the concrete, the mechanical properties decrease. Fiber concrete submerged in seawater has higher mechanical properties than normal concrete. Optimum fiber length length in fiber concrete from the results of this study is 25 mm

Studi Keterlambatan Proyek Pembangunan Ruko Business Park Citaland City Losari Makassar

Tolok ukur keberhasilan proyek pada umumnya dilihat dari waktu penyelesaian yang singkat dengan biaya yang minimal tanpa meninggalkan mutu hasil pekerjaan. Keterlambatan pada suatu proyek pembangunan merupakan suatu masalah yang dapat menyebabkan kerugian pada beberapa pihak, baik kontraktor pelaksana maupun pemilik proyek atau pemilik. Penundaan penyelesaian proyek memiliki dampak terhadap biaya yang signifikan. Dalam penelitian ini mengkaji tentang penyebab dan pengaruh keterlambatan Proyek Pembangunan Ruko Business Park Citraland City Losari Makassar. Pada pekerjaan proyek ini terjadi keterlambatan penyelesaian pembangunan berdasarkan waktu yang sudah ditentukan. Metode yang digunakan untuk pengumpulan data, yaitu: studi literatur, wawancara, dan kuesioner. Pembagian kuesioner dilakukan dua kali tahapan, survai pendahuluan dan survai utama. Hasil survai, diidentifikasi beberapa faktor penyebab keterlambatan proyek pada pelaksanaan proyek sebanyak 6 faktor dan 25 varibel dan jumlah responden yang mengembalikan kuesioner sebanyak 24 orang. Beberapa faktor yang paling mempengaruhi penyebab keterlambatan pelaksanaan proyek berdasarkan nilai tingkat risiko (R) dari variabel yang paling mempengaruhi penyebab keterlambatan pelaksanaan proyek, yaitu: keterlambatan akibat kesalahan sub kontraktor, kemampuan tenaga kerja kurang, dan kurangnaya kedisiplinan tenaga kerja bernilai R sebesar 6 kategori medium (sedang), sedangkan pengaruh musim hujan dengan nilai R sebesar 15 kategori high (tinggi), sehingga perlu dilakukan penanganan risiko (risk reduction) untuk mengurangi risiko

Examining Polyethylene Terephthalate (PET) as Artificial Coarse Aggregates in Concrete

This study aims to examine the effect of recycled Polyethylene Terephthalate (PET) artificial aggregate as a substitute for coarse aggregate on the compressive strength and flexural strength, and the volume weight of the concrete. PET plastic waste is recycled by heating to a boiling point of approximately 300°C. There are five variations of concrete mixtures, defined the percentage of PET artificial aggregate to the total coarse aggregate, by 0, 25, 50, 75 and 100%. Tests carried out on fresh concrete mixtures are slump, bleeding, and segregation tests. Compressive and flexural strength tests proceeded based on ASTM 39/C39M-99 and ASTM C293-79 standards at the age of 28 days. The results showed that the use of PET artificial aggregate could improve the workability of the concrete mixture. The effect of PET artificial aggregate as a substitute for coarse aggregate on the compressive and flexural strength of concrete is considered very significant. The higher the percentage of PET plastic artificial aggregate, the lower the compressive and flexural strength, and the volume weight, of the concrete. Substitution of 25, 50, 75 and 100% of PET artificial aggregate gave decreases in compressive strength of 30.06, 32.39, 41.73 and 44.06% of the compressive strength of the standard concrete (18.20 MPa), respectively. The reductions in flexural strength were by respectively 19.03, 54.50, 53.95 and 61.00% of the standard concrete's flexural strength (3.59 MPa). The reductions in volume weight of concrete were by respectively 8.45, 17.71, 25.07 and 34.60% of the weight of the standard concrete volume of 2335.4 kg/m3 Doi: 10.28991/cej-2020-03091626 Full Text: PD

POTENSI LIMBAH FLY ASH BATU BARA PLTU DI SULAWESI SELATAN SEBAGAI BAHAN DASAR MORTAR GEOPOLIMER

Fly ash is one of the residues produced from burning coal which consists of fine particles. Fly ash, also knownas fly ash, is one of the industrial wastes from the PLTU in South Sulawesi which is rich in silica and aluminum whichcan be used as a sturdy binder through the polymerization process. South Sulawesi Province itself has several coal-firedpower plants. PLTU annually produces a lot of fly ash or fly ash waste. The waste produced by the PLTU raises theproblem that arises is how to use the garbage so as not to pollute the environment and can be used mainly in theconstruction world. Because of these problems, it is necessary to research the potential waste of PLTU coal-fired fly ashin South Sulawesi as a base material for geopolymer mortar. The research method used is the experimental method in thelaboratory. The method in making and testing mortar samples refers to SNI 03-6825-2002. The composition of aggregatehas a ratio of fly ash: sand of 1: 2.75, and the composition of activator 10 Molar NaOH, the ratio of Na2SiO3: NaOH is 2.The results of the research are the most dominant chemical composition of Fly ash, namely silicate (SiO2), Aluminum(Al2O3 ), Ferrum (Fe2O3) and Lime (CaO). Fly Ash type A and Fly Ash type A are class C fly ash. The compressivestrength of Geopolymer mortar based on fly ash A is much higher than geopolymer mortar based on fly ash B, and thecompressive strength of geopolymer mortar is very significant with the age of geopolymer mortar

Teknik Keselamatan dan Kesehatan Kerja

Keselamatan dan kesehatan kerja merupakan suatu pemikiran dan upaya untuk menjamin keutuhan dan kesempurnaan baik jasmani maupun rohani. Dengan keselamatan dan kesehatan kerja maka diharapkan tenaga kerja dapat melakukan pekerjaan dengan aman dan nyaman serta mencapai ketahanan fisik, daya kerja, dan tingkat kesehatan yang tinggi. Tantangan K3 di era industrialisasi dan globalisasi yang berjalan beririsan dewasa ini disamping memberikan kemudahan proses produksi dapat pula menambah jumlah, ragam bahaya di tempat kerja maupun tingkat keseriusan kecelakaan kerja. Buku ini diharapkan dapat mengisi ruang-ruang kosong informasi yang dibutuhkan oleh para penggiat kesehatan dan ketenagakerjaan dalam upaya menciptakan zero accident di perusahaan atau lingkungan kerja. Buku ini membahas bagian-bagian menarik dan penting seperti: Bab 1 Peranan Keselamatan Dan Kesehatan Kerja Dalam Dunia Industri Bab 2 Dasar Teknik Keselamatan dan Kesehatan Kerja di Dunia Industri Bab 3 Faktor-Faktor Kecelakaan Kerja dan Pencegahannya Bab 4 Undang – Undang dan Organisasi Keselamatan Kerja Bab 5 Higiene Perusahaan dan Kesehatan Kerja Bab 6 Keselamatan Kerja Bidang Kebakaran Bab 7 Keselamatan Kerja Bidang Transportasi dan Lalu Lintas Bab 8 Keselamatan Kerja Bidang Perminyakan, Pertambangan dan Perkebunan Bab 9 Bahan Berbahaya dan Keselamatan Kerja Bab 10 Peralatan Perlindungan Diri Bab 11 Investigasi Kecelakaan Kerja dan Pencegahan Bab 12 Penerapan Sistem Manajemen Keselamatan dan Kesehatan Kerja berdasarkan OHSAS 18001:2007 di Perusahaan Bab 13 Peranan Pemerintah dan Ikatan Profesi Penyuluhan dan Latihan Keselamatan Kerj