The Use of The Semanding Tuban Limestone as A Partial Replacement of Coarse Aggregate in Concrete Mixes N Rochmah 1 , G Sarya 2 , F Setiawan 3 {nurulita889@gmail.com 1 } 1,2,3 Civil Engineering,Universitas 17 Agustus 1945 Surabaya, Indonesia Abstract. Concrete is the most widely used material in the world. Expensive construction can be caused by t h e increasing cost of concrete. In recent years, concrete production has increased which means consumption of coarse aggregate also increased. Natural coarse aggregate is gravel. Due to the growth in the construction industry, the demand for gravel is increasing rapidly, therefore gravel is expensive. In Semanding Tuban, there is limestone which is greater available than gravel in order to reduce concrete cost. In this case there is a need to study the concrete with limestone from Semanding Tuban as coarse aggregate in order to get better understanding of limestone in concrete mixes. The aim of this research is to investigate the compressive strength of the concrete, in which limestone from Semanding Tuban was used as coarse aggregate is partially or completely replaced. The coarse aggregate was replaced with 0%, 25%, 50%, 75%, 100% by limestone from Semanding Tuban, respectively. The compressive strengths of concrete specimens for respective mix proportions were tested at 14 and 28 days of water curing. In addition the source of aggregate properties was considered in this research: Los Angeles abrasion, absorption and specific gravity for coarse aggregates and fine aggregate. The result of the compressive strength concrete of limestone from Semanding Tuban as addition showed that increased by 0% to 50%, but it decreased to 50% to 100%. Keywords: Concrete, Coarse Aggregate, Limestone, Compressive Strength 1. Introduction Concrete is the widely construction material used in building structures[1]. Concrete is the result of mixing of cement, water, fine aggregate and coarse aggregate. In this era the use of concrete is increasing[2], because the concrete-making material is easy to obtain and it has a large compressive strength, the concrete is easy to form in accordance with desires, maintenance costs are small and more resistant to various weather. This day, concrete production is getting increase. In the need for concrete manufacturing materials has caused a lot of aggregate mining as one of the large concrete mixture materials which has resulted in a reduction in the number of natural sources available for making concrete. ACHITS 2019, July 30-31, Surabaya, Indonesia Copyright © 2019 EAI DOI 10.4108/eai.30-7-2019.2287755