International Journal of Multidisciplinary Research and Publications ISSN (Online): 2581-6187 64 Salma Alwi, Sujiati Jepriani, Garini Widosari, and Dhiana Dwi Widiawati, “Effect of Addition of Iron Lathe Waste as an Additive to Normal Concrete Compressive Strength and Tensile Strength of Concrete,” International Journal of Multidisciplinary Research and Publications (IJMRAP), Volume 6, Issue 6, pp. 64-68, 2023. Effect of Addition of Iron Lathe Waste as an Additive to Normal Concrete Compressive Strength and Tensile Strength of Concrete Salma Alwi 1 , Sujiati Jepriani 2 , Garini Widosari 3 , Dhiana Dwi Widiawati 4 1,2,3,4 Civil Engineering Department, Samarinda State Polytechnic, Samarinda, Indonesia-75242 Email address: salmaalwi@polnes.ac.id Abstract— Concrete is obtained from mixing fine and coarse aggregate materials, namely sand, crushed stone and other materials by adding sufficient cement adhesive and water. Concrete itself is a material that is often used because it is durable, inexpensive, and can be moulded into complex shapes. Concrete has a fairly large compressive strength but has a small tensile strength. To overcome these problems, concrete with special characteristics was found, namely steel fiber concrete (BSB). However, steel fiber is quite expensive if used for small scale construction. In this research, lathe iron waste was used as an added ingredient in the concrete mixture with varying levels of 0.75%, 1.5%, 2.25%, 3%, 3.75%. From this composition, concrete compressive strength and concrete split tensile strength tests were then carried out. The results showed that the addition of iron lathe in concrete to the compressive strength of concrete characteristics did not really show a significant difference in results, namely a decrease in compressive strength of 0.0496% in the 1.5% variation of 22.24 MPa when compared to the value in the 0% variation (normal) of 22.25 MPa. The addition of iron lathe in concrete to the tensile strength of concrete characteristics shows more results, namely an increase of 10.739% in the 2.25% variation of 10.04 MPa when compared to the value in the 0% (normal) variation of 9.07 MPa. Keywords— Compressive strength, Split Tensile Strength, Iron Lathe. I. INTRODUCTION Concrete is made up of fine and coarse aggregate materials such as sand, crushed stone and other materials by adding sufficient cement adhesive and water. Concrete itself is a structural material that is most often used for the construction of buildings, roads, bridges and others. Concrete is often used because it is durable, inexpensive, can be easily molded into complex shapes and has considerable compressive strength. However, concrete itself has weaknesses, namely being brittle, low specific gravity and tensile strength and uneven load distribution due to the relatively small load absorption in the concrete. In overcoming these things, concrete with special characteristics was found, namely steel fiber concrete (BSB). The purpose of adding fiber to concrete is to increase the tensile strength of the concrete, considering that the tensile strength of concrete is low. At the beginning of research on steel fiber concrete (BSB), the use of steel fiber concrete (BSB) was not too much due to the high cost of steel fiber fabrication. However, the use of steel fiber concrete (BSB) has recently become more attractive and the use of steel fiber concrete (BSB) is increasing throughout the world. However, steel fiber itself is still considered quite expensive if used for small scale construction. Based on this, through this research, material in the form of lathe iron waste is used as an additive to normal concrete which is intended to determine the increase that occurs in compressive strength and in tensile strength of concrete by adding lathe iron waste fiber as an additive to normal concrete. II. LITERATURE REVIEW According to SNI 03-2834-2000 concrete is a mixture of Portland cement or other hydraulic cement, fine aggregate, coarse aggregate and water with or without added ingredients to form a solid mass. In its development concrete undergoes changes in variations, one of which is fiber concrete. Fiber concrete is a mixture of concrete plus fiber, generally in the form of rods with a size of 5-500μm with a length of about 25 mm (Mulyono, 2004). Fiber concrete is used in constructions that must have large surfaces where temperature, oxidation and evaporation have a major influence on the amount of expansion shrinkage, such as airport runways, roof plates, roads, and others. Types of fiber: 1. Metal fiber 2. Polymeric or synthetic fiber 3. Fiberglass 4. Natural fiber Fiber concrete composing material: 1. Composite Portland cement 2. Coarse aggregate (gravel) 3. Fine aggregate (sand) 4. Water 5. Iron lathe waste Fig 1. Iron lathe waste that will be used