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Penggunaan fly ash sebagai bahan tambahan untuk menggantikan sebagian semen merupakan salah satu hal untuk mendorong penggunaan material alternatif. Penelitian ini mengkaji pengaruh persentase substitusi fly ash sebesar 10%, 30%, dan 50% dengan penambahan zat aditif superplasticizer sikament-NN (Tipe F) dengan dosis 1,2% terhadap kemudahan pengerjaan (workability) dan kekuatan tekan beton. Kinerja beton dianalisis berdasarkan kekuatan tekannya pada hari ke-28 dab kelancaran kerjanya berdasarkan slump. Hasil penelitian ini menunjukan bahwa kombinasi penggunaan fly ash dan superplasticizer sikament-NN (Tipe F) dapat meningkatkan kemudahan adukan, dengan nilai slump maksimum mencapai 14,3 cm pada presentase fly ash 50%. Namun, peningkatan kelacakan ini berbanding terbalik dengan kekuatan tekan yang konsisten menurun seiring dengan peningkatan penambahan fly ash. Nilai kuat tekan maksimum dicapai oleh campuran beton yang hanya menggunakan superplasticizer tanpa fly ash sebesar 320,50 kg/cm2, sementara nilai yang optimal ditemukan pada variasi persentase 10% dengan penambahan superplasticizer 1,2% menghasilkan kuat tekan sebesar 307,65 kg/cm2, sehingga penggunaan kombinasi ini diharapkan dapat memberikan kontribusi efisiensi bagi rekayasa sipil.

Beton sebagai material utama konstruksi sering mengalami panas hidrasi yang menyebabkan perbedaan suhu permukaan dengan suhu inti, akan berpotensi retak dini dan penurunan kuat tekan. Penelitian ini menganalisis potensi air es dan fly ash 10% substitusi semen untuk memperkecil suhu beton mutu 35 MPa dengan aditif tipe D (retarder) dan F (superplasticizer), serta pengaruhnya terhadap kuat tekan. Metode deskriptif menggunakan data sekunder mix design tiga variasi: non fly ash, fly ash 10% dan fly ash 10%+air es 10°C. Suhu beton segar diukur dengan thermogun/thermometer lalu kuat tekan uji silinder diameter 150x300 mm umur 7 hari dan 28 hari dengan total 18 benda uji. Hasil menunjukkan suhu beton segar non fly ash berada pada rentang normal, beton fly ash 10% turun 1-2°C (reaksi pozzolanik lambat yang mengurangi panas hidrasi dari C2S, C3S, dan C3A), beton fly ash 10% + air es turun 5-6°C. Kuat tekan 7 hari menunjukkan beton non fly ash 33,69 MPa, beton fly ash 10% 34,14 MPa, beton fly ash 10%+air es 34,73 MPa. Pada umur 28 hari menunjukkan beton non fly ash 39,73 MPa, beton fly ash 10% 39,80 MPa, dan beton fly ash 10%+air es 39,65 MPa – semua melebihi mutu rencana.

Beton merupakan material utama konstruksi yang masih memiliki kelemahan pada kuat tekan dan permeabilitas. Inovasi dengan penambahan Superplasticizer diharapkan mampu meningkatkan kualitas beton. Permasalahan penelitian ini adalah bagaimana pengaruh variasi dosis Superplasticizer (1%, 1,5%, dan 2% dari berat semen) terhadap kuat tekan dan permeabilitas beton dibandingkan beton normal. Penelitian ini menggunakan metode eksperimen dengan membuat 48 sampel beton silinder dan kubus yang diuji kuat tekan pada umur 7, 14, dan 28 hari serta permeabilitas pada umur 28 hari. Hasil penelitian menunjukkan bahwa penambahan Superplasticizer mampu meningkatkan kuat tekan dan menurunkan permeabilitas, sehingga dapat menghasilkan beton yang lebih kuat, kedap air, dan tahan lama.

Parepare City is located on the coast with significant fisheries and maritime potential. The processing and consumption of shellfish in this city produces a lot of shellfish waste, which is often not utilized and accumulates into an environmental problem. To improve the properties of concrete, several types of additives that have certain functions are added to the concrete mixture, namely increasing the workability, durability, and hardening time of concrete. This study aims to determine the compressive strength of concrete and the composition of coarse aggregate of shells with superplasticizer added materials that are optimally produced. Using an experimental method carried out at the Laboratory of Structure and Materials, Muhammadiyah University of Parepare. The results showed that substitution of coarse aggregate with 5% shellfish waste and 0.5% superplasticizer increased the compressive strength of concrete at the ages of 7, 14, and 28 days. The 10% substitution still meets the compressive strength requirements at 28 days, although slightly lower than normal concrete. Substitution of shells up to 5% increases the compressive strength of concrete, and the 10% content is optimal, reaching the maximum value without significant decline. It is recommended that the use of shells as a substitute for coarse aggregate does not exceed 10% for optimal results and meets the planned compressive strength of 25 MPa.

Self Compacting Concrete (SCC) is an innovative concrete that can compact itself (without vibrators) and flow under its own weight to saturate the shape without segregation. The SCC material is not much different from ordinary concrete, namely coarse aggregate, fine aggregate, cement, water, only SCC has additional ingredients such as superplasticizer. This research uses quantitative methods. The aim of this research is to determine the workability, compressive strength, flexural strength of SCC concrete with the addition of 2% fiberglass to each sample with added material in the form of sika visconcrete with variations of 0%, 1%, 1.5%, and 2%, % of the cement weight. Slump flow testing was carried out which was obtained from several variations of SV `0%, 1%, 1.5%, 2%, the slump flow values were obtained for 80 mm fiber concrete and 550 mm, 575 mm, 600 mm SCC concrete with the time taken to reach 500 mm of 4.25 seconds, 3.57 seconds and 2.11 for SCC concrete. The compressive strength value of the cylinder size (15 x 30) in samples BFS0, BFS1, BFS2BFS3 aged 28 days obtained a compressive strength of 30.29 Mpa, 34.44 Mpa, 31.23 Mpa, while the flexural strength test of the beam was 15 x 15 x 60 d samples BFS0, BFS1, BFS2BFS3 obtained results of 3.11 Mpa, 4.35 Mpa, 3.64 Mpa and 3.29 Mpa, excessive use of visconcrete in the concrete mixture can reduce the strength of the samples.

In the current development of concrete innovation technology, there are also expensive materials that are cheap as concrete additives for the efficiency of the cost of making concrete. cheap and can be used as concrete innovation. The purpose of adding palm fiber fiber is to improve the quality of concrete, both compressive strength and split tensile strength. The method used in this study was experimentation by adding palm fiber to the SCC concrete mixture with variations of 2%, 4% and 6%. As for the addition of chemical substances, the superplasticizer admixture aims to make it easier for SCC concrete to achieve a slump flow value that meets the requirements. After testing, the highest compressive strength test specimen is BC 1 2% palm fiber worth 19.38 MPa and for the lowest compressive strength test is BC 2 6% palm fiber worth 5.46 MPa. And for the split tensile strength test the highest is BC 4 2% palm fiber worth 9.47 MPa and for the lowest split tensile strength test is BC 3 6% palm fiber worth 5.82 MPa.

Self-compacting concrete (SCC) is self-flowing concrete that can be printed on formwork with very little or no compaction. One of them is by adding admixture superplasticizer. The purpose of this research is to determine the effect of superplasticizer admixture with various variations on flexural strength. The method used in this research is the experiment of adding superplasticizer admixture to the concrete mixture with variations of 3%, 4% and 5%. The sample was made of 3 test objects in the form of blocks with dimensions of 15 cm x 20 cm x 100 cm for a design value of 15 MPa. Based on the results of the flexural strength test of concrete beams after 28 days of flexural strength testing, the highest yield was obtained in the second sample of 4% mixture with a maximum P load of 32.2 KN after converting to 18.22 MPa. Whereas for the 1st sample it was a 3% mixture with a maximum P load of 22 KN after converting to 12.44 MPa and for the 3rd sample it was a 5% mixture with a maximum P load of 22.9 KN after converting it to 12.95 MPa. 3. It was found that the average of the 3 samples was 14.54 MPa, a little more to exceed the target of 15 MPa.

Concrete is a material that is commonly used when doing construction work today. Because concrete has several advantages when compared to other materials, such as being easy to form, resistant to weather changes, has high compressive strength, and is durable. In this study the use of Silica Fume as an additive to flow concrete has the function of improving the quality of flowing concrete. Silica Fume has an important role in affecting the chemical and mechanical properties of concrete. Judging from its chemical properties, Silica Fume geometrically fills the voids between cement materials, and causes the pore diameter to decrease and the total pore volume to decrease. Meanwhile, from its mechanical properties, Silica Fume has a pozzolanic reaction (a material containing silica/silica dioxide and alumina compounds) which reacts to the limestone released by the cement. The aim of the research is to increase the maximum compressive strength of flowing concrete by using Silica Fume added with varying percentages of 0%, 5%, 6%, 7.5%, 9%, 10.5% and 12% and using a superplasticizer of 1.5 %. From the results of the research conducted, it was found that flowing concrete with added silica fume on concrete compressive strength was able to reach 7.5% at 7 days of age of 25.91 MPa and at 28 days of concrete age was obtained at 26.19 MPa.