Civilla : Jurnal Teknik Sipil Universitas Islam Lamongan ISSN (Online) 2620-7222 Volume 06 Number 2 Year 2021 ISSN (Print) 2503-2399 197 The Effect of Seawater on The Compressive Strength and Split Tensile Strength in Self Compacting Geopolymer Concrete https://doi.org/10.30736/cvl.v2i2 The Effect of Seawater on The Compressive Strength and Split Tensile Strength in Self Compacting Geopolymer Concrete Herwina Rahayu Putri 1 , Firman Paledung 2 , Erniati Bachtiar 3* , Popy Indrayani 4 , Ritnawati Makbul 5 Hamayatul Ummah Syarif 6 1 Student of Master of Infrastructure and Environmental Engineering, Fajar University, Makassar. 2 Student of Civil Engineering Study Program, Fajar University, Makassar. 345 Lecturer of Master of Infrastructure and Environmental Engineering, Fajar University, Makassar. 6 Lecturer of Engineering Faculty, Fajar University, Makassar Email : 1 Herwinarahayuputri26@gmail.com. 2 firmanpaledung733@gmail.com. 3* erni_nurzaman@yahoo.com, 4 poppyindrayani@hotmail.co.jp. 5 ritnawati.nn@gmail.com. 6 humayat ulu@yahoo.com. A R T I C L E I N F O A B S T R A C T Article History : Article entry : 2021-10-11 Article revised : 2021-11-04 Article received : 2021-12-09 Fly ash is a kind of trash that may degrade the quality of the air. As a result, it is critical that it be used as an ecologically beneficial material. The aim of this research was to evaluate the strength of self-compacting geopolymer concrete (SCGC) cured in seawater, as well as to compare SCGC with and without saltwater. In this research, a cylindrical specimen with a diameter of 10 cm and a height of 20 cm was utilized as the specimen. Fly ash is used in proportion to fine and coarse aggregates at a ratio of 1: 0.65: 1.5. Using a 0.4 activator to binder ratio. The molarity ranges utilized were 11 M - 15 M. Compressive strength and split tensile strength tests were conducted on 28-day-old concrete. The findings indicated that when the molarity of SCGC treated with seawater increased from 11 to 15 M, the compressive and split tensile strengths increased. Compressive strength values were greatest in SCGC treated at room temperature when an activator of 13 M was used, and compressive strength values dropped in SCGC treated at room temperature when an activator greater than 13 M was used. Keywords : SCGC, Fly Ash, Compressive Strenght, Split Tensile Strenght, Sea water IEEE Style in citing this article : [Heading citation] One, N. P., & Second, N. P. (Year). Article Title. Civilla : Universitas Islam Lamongan, v(n), Start page – End page. [heading citation contents] This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License. Allows readers to read, download, copy, distribute, print, search, or link to the full texts of its articles and allow readers to use them for any other lawful purpose. Available online at https://jurnalteknik.unisla.ac.id/index.php/CVL https://doi.org/10.30736/cvl.v2i2