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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.

Self-Compacting Concrete (SCC) requires a high cement content, which contributes to increased carbon emissions; therefore, this study evaluates the effect of partial cement substitution with fly ash (5%, 10%, and 15%) and the addition of Polyethylene Terephthalate (PET) waste (0.5% and 0.7%) on the mechanical properties of SCC with a target strength of f’c 30 MPa. The research employed laboratory experimental methods, including fresh concrete tests (slump flow, L-box, and V-funnel) and hardened concrete tests (compressive, tensile, and flexural strength) at 7 and 28 days. The results indicate that fly ash substitution enhances compressive strength, with the highest value of 49.59 MPa achieved at 5% fly ash at 28 days, exceeding normal concrete (34.73 MPa). The addition of PET tends to reduce compressive strength due to increased porosity; however, it significantly improves flexural strength, as the combination of 5% fly ash and 0.5% PET achieved 4.7 MPa compared to 2.9 MPa for normal concrete. Overall, the combination of fly ash and PET waste shows potential for application in structural elements requiring high flexural performance.

Consistent and efficient concrete quality in each implementation is one of the main factors in the success of construction projects. Concrete as a structural material requires strict quality control in order to meet the technical standards that have been set. One way to improve the quality of concrete is to add certain additives to the job mix formula (JMF). This research is focused on the application of SG type additives known as chemical-based additives to improve the properties of fresh concrete and hard concrete. SG additives have an important function in increasing workability, speeding up or slowing down the binding time as needed, maintaining quality stability, and strengthening concrete finishes. In this study, a comparison was made between a concrete mixture with SG additives and a concrete mixture without additives. The tests included slump parameters, initial binding time, and compressive strength at 7 and 28 days of age. The test results showed a significant difference, especially in the improvement of the consistency and compressive strength of concrete with the use of additives. The results of the discussion showed a comparison of Trial Mix 1 and Trial Mix 2 that are different in terms of material composition, cost efficiency, and compressive strength of concrete. Trial Mix 2 with the composition of cement, admixture, water, and aggregate (sand and split) showed more optimal results. The compressive strength achieved was 821,396.00 kg/cm² at the age of 28 days. In terms of cost, Trial Mix 2 requires Rp. 351,582.00 per m³, with an efficiency difference of around Rp. 32,953.00 per m³ compared to the previous mix

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.

Concrete is an artificial stone made from a mixture of cement, sand, aggregate and water. For this reason, this construction material is considered very important to continue to be developed. One effort to develop is by improving the weak properties of the concrete itself. From this, researchers will use additional materials such as fiber palm fiber and sika visconcrate in the concrete mixture. Fiber fiber itself has durable properties and does not rot easily in open conditions or embedded in the ground, while sika visconcrate is a chemical that is used as an additive in the mixture to increase the workability, quality and strength of concrete with the desired properties. The method used in this research is quantitative experimentation. The aim of this research is to determine the characteristics of concrete using palm fiber and sika visconcrate with variations of 3%, 5% and 7% from normal concrete. The results of the research show that the average compressive strength of normal concrete is 25,572 MPa, 3% SI+SV variation concrete has an average of 27,365 MPa, 5% SI+SV variation concrete has an average of 26,704 MPa, and 7% SI+ SV variation concrete The average is 26,044 MPa. The split tensile strength test results of normal concrete averaged 6.074 MPa, 3% SI+SV variation concrete averaged 6.444 MPa, 5% SI+SV variation concrete averaged 7.852 MPa, and 7% variation concrete averaged amounting to 8,148 MPa.    

This study investigates the effect of roof tile waste used as a partial replacement for fine aggregate on the fresh and hardened properties of concrete, with the aim of promoting more sustainable and environmentally friendly construction materials. The research employed an experimental laboratory method with quantitative analysis. Roof tile waste was incorporated into concrete mixtures at substitution levels of 0%, 5%, 10%, 15%, and 20% by weight of fine aggregate. The workability of fresh concrete was evaluated using slump tests in accordance with SNI 1972:2011, while compressive strength tests were conducted on cylindrical specimens after 28 days of curing based on SNI 1974:2011 standards. The results indicate that increasing the proportion of roof tile waste reduced concrete workability, as shown by a decrease in slump values from 10 cm in the control mix to 8 cm at the 20% replacement level. Compressive strength also exhibited a declining trend, decreasing from 14.63 MPa to 11.90 MPa at the highest substitution, representing an approximate reduction of 18.7%. Nevertheless, concrete containing 5% roof tile waste achieved a compressive strength of 14.32 MPa, which is comparable to normal concrete. These findings suggest that roof tile waste can be utilized as a partial fine aggregate replacement at limited levels. A 5% substitution was identified as the optimal proportion to maintain acceptable workability and strength while supporting sustainable concrete development.

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.

The majority of road construction in Indonesia uses flexible pavement, namely Asphalt Concrete (AC). Therefore, to meet the need for asphalt, Asbuton was carried out. This research aims to determine the effect of Asbuton content, mixing temperature, and compaction temperature on the workability index value. Therefore, research was carried out regarding the workability of the AC-WC mixture with Asbuton B 50/30 The preparation of test objects was carried out using the dry mixing method. The Asbuton content used was 10% and 15% and the mixing temperature was varied, namely 160⁰ C, 170⁰ C, 180⁰ C 190⁰ C, and 200⁰ C and the compaction temperature was 110⁰ C, 120⁰ C, 130⁰ C, 140⁰ C, and 150⁰ C at the level optimum asphalt. Then, the data obtained is processed using a statistical approach. The research results showed that the AC-WC mixture with 10% Asbuton content and varying mixing and compaction temperatures had a workability index value from 2.9890 to 5.7737. Meanwhile, the AC-WC mixture with 15% Asbuton content and varying mixing and compaction temperatures has a workability index value ranging from 3.3252 to 6.9845. This shows that variations in Asbuton content, mixing temperature and compaction temperature influence the workability index value of the AC-WC mixture.

The rapid expansion of construction activities has led to increased concrete consumption, resulting in excessive exploitation of natural aggregate resources and growing environmental concerns. To mitigate this issue, ceramic waste has been investigated as an alternative material in concrete production. This study examines the effect of ceramic waste powder used as a filler on the workability and compressive strength of concrete. Ceramic waste powder was applied as a partial replacement for fine aggregate at proportions of 0%, 15%, 25%, 35%, and 45%. The concrete mixtures were produced using Ordinary Portland Cement Type I, natural sand, crushed stone as coarse aggregate, and potable water, all conforming to Indonesian National Standards (SNI). Workability was assessed through slump tests in accordance with SNI 1972:2008, while compressive strength tests were performed on cylindrical specimens at 28 days following SNI 1974:2011. The compressive strength for each mixture was determined from the average of three specimens. The results show that increasing ceramic waste content slightly reduced slump values, from 17.20 cm in the control mix to 16.60 cm at 45% replacement, although all mixtures met the required workability standards. A gradual decrease in compressive strength was also observed, from 17.79 MPa to 16.65 MPa at the highest replacement level. However, this reduction was not significant, indicating that ceramic waste powder can be used in normal-strength concrete without substantially affecting performance. The utilization of ceramic waste therefore represents a sustainable alternative to reduce natural aggregate consumption while maintaining acceptable concrete properties.