The construction of multi-stories buildings is increasing rapidly. In concrete construction, various studies and innovations have been carried out in order to obtain high strength concrete. The use of limestone either as a substitute for fine aggregate, as a substitute for coarse aggregate or as a substitute for fine aggregate and even coarse aggregate in a concrete mixture is still lacking. In South Sulawesi, large quantities of limestone are found in several regencies. Enrekang Regency is one with considerable limestone potential which is about 74.75 km2 or an estimated geological of 3.7 billion cubic meters. Most limestone is made into split stones that can be used as construction materials. Limestone can be processed into split or powder which can be used as a replacement for sand in concrete mixture. The results of the concrete at 28 days with a mixture of natural sand as fine aggregate and limestone split as coarse aggregate, w/c ratio of 0.20 produced a value of f’c = 59.26 MPa. ft = 4.51 MPa (0.61 √f’c), and fr = 7.18 MPa (0.93 √f’c). The average modulus of elasticity at 28 days with a mixture of limestone powder as fine aggregate and limestone split as coarse aggregate produced a value of Ec = 46960.25 MPa (6325 √f’c) with Poisson’s ratio υ = 0.3847.

Filler has an important role in the HRS-WC mixture besides aggregates and asphalt due to its functions to fill the void in the asphalt mixture so that it could produce more friction resistance and high interlocking aggregate. The use of filler in the mixture is limited in number because too much filler will lead to the stiffer and easily cracked mixture. On the contrary, the lower values could lead to the easily deformed and too flexible mixture. Previous researchers have studied the use of the waste of crude palm oil (CPO) ash as a filler. This research aims to study the performance of the HRS-WC mixture using CPO ash as a filler. The asphalt content used was 5.9%; 6.33%; 6.75%; 7.18% and 7.6%, while the proportion of CPO ash waste is 0%, 25%, 50%, 75% and 100%. The mixture gradation is made using a gap-graded and half gap-graded mixture. The results showed that the stability is higher when 25% of CPO ash proportion is used, but it is decreased again when the proportion is larger than 25%. The use of a small asphalt content will increase the value of VIM. The flow value decreases when 32% of CPO ash proportion is used and increases again over the use of 32%. The use of a large amount of CPO ash filler in the mixture will increase VMA. While the VFB will decrease if the larger amount of CPO ash is used. The immersion index of the mixture can still be maintained even when the use of CPO ash is increased. The use of CPO ash as a substitute for filler in the HRS mixture - WC must be balanced with the increasing of asphalt mixture.

Durability is the ability of asphalt concrete to accept repetition of traffic loads, friction, and weather and climate wear, while permeability is the ability of pavement surfaces to hold water seepage into pavement. Besides, the pore volume in the mixture is one of the most important AC-WC characteristics which are related to the level of water impermeability in the pavement layers. The purposes of this study is to investigates the effect of adding coconut fibers by 0%, 0.5%, 1%, 1.5% and 2% on durability and permeability the surface layer of Laston BC. The results obtained are the stability of the asphalt mixture in accepting the load without changing the plastic shape and following the trend of the 2nd order polynomial line. VIM values tend to rise then decrease until 48 hours immersion. It is found that the use of coconut fibers improved the impermeability properties of the surface layer of Laston BC. The value of mixed flow is influenced by the addition of coconut fibers, where if the fibers increase to 1%, then the flow will decrease. The durability value due to the addition of 1% and 1.5% coconut fibers can only be tolerated at the submergence limit of Laston BC for 30 hours while the addition of coconut fibers from 0% to 2% Laston BC can only submerged for 12 hours. The permeability values of the mixture decreases by 0.51 cm/sec for each addition of 0.5% coconut fibers.

Bottom ash (abu dasar) adalah sisa pembakaran batu bara di Indonesia di kategorikan sebagai limbah (B3). Kandungan logam berat dalam limbah B3 menyebabkan pencemaran lingkungan. Bottom ash melimpah dan kurang dimanfaakan. Oleh karena itu berbagai inovasi dilakukan peneliti agar penggunaan kontruksi beton layak digunakan terhadap pengaruh hujan asam serta pengelolaan bottom ash sebagai material konstruksi beton. Pada penelitian ini persentase substitusi bottom ash agregat halus sebanyak 0%, 25%, 35% dapat digunakan untuk campuran beton dengan perendaman asam sulfat pH-4. Dengan benda uji yang digunakan berukuran 15 cm x 30 cm dan 60 cm x 15 cm x 15 cm sebanyak 45 sampel, menggunakan metode American Concrete Institute (ACI). Pengujian tersebut berupa pengujian kuat tekan. kuat tarik belah dan kuat lentur beton dengan mutu rencana sebesar 30 MPa. Pada umur 28 hari didapatkan nilai kuat tekan sebesar 32,727 Mpa, 33,859 Mpa, 36,782 Mpa. Beton dengan substitusi bottom ash sebagai agregat halus dengan variasi 0%, 25% dan 35% mengalami peningkatan kekuatan seiring bertambahnya persentase substitusi bottom ash dimana semakin tinggi persentase substitusi bottom ash maka kekuatan beton semakin tinggi, sehingga dapat dikatakan bahwa persentase substitusi bottom ash berbanding lurus dengan kekuatan beton.