Document Type : Research Paper

Authors

Civil Engineering Department, University of Technology, Baghdad, Iraq,

Abstract

Starch act as natural polymer has been got from Wheat, Tapioca, and Corn. Corn starch has been investigated as biopolymer and has been added to concrete in different percentages (0%, 0.5%, 1%, and 1.5%) by cement weight and the study shows the effect of using starch on some properties of concrete in the fresh state ( slum and fresh density) and at hardened state (compressive strength, splitting tensile strength and flexural strength) at 28 days. The mix proportion was(1:2.3:2.3) (cement: sand: gravel) respectively and at constant w/c equal to 0.47.The results indicate that the optimum percentage of starch addition was 0.5%, so it showed an increase by 50%in compressive strength and splitting tensile strength; while, the increases in flexural strength were 26%. Slump showed a 25% increase and fresh density showed a 2.5% increase at 0.5% addition of starch.

Keywords

[1] J. Plank, “Products and Applications of Biopolymers” Janeza Trdine, Croatia, 2012.
[2] M. V. Karandikar, S.B. Sarase P.G. Lele and S.A. Khadilkar,,, Use of Natural Biopolymers for Improved Mortar& Concrete Properties of Cements, Quality & Product Development, L.B.S. Marg, Thane 400 604, India.
[3] A. Akindahunsi, W. Schmidt and S.E. Iyuke, “The Influence of Starches on some Properties of Concrete, Advances in Cement and Concrete Technology in Africa” p.p. 637-646,2013.
[4] J. Plank, ,,Applications of Biopolymers in Construction Engineering, TU Munich, Institute for Inorganic Chemistry, Garching, Germany,P.3,2005.
[5] Central Organization for Standardization and Quality Control, COSQC, “Specification for Portland Cement, IQS 5-1984”, Baghdad, Iraq, 1984. (In Arabic).
[6] Central Organization for Standardization and Quality Control, COSQC, “Aggregates from Natural Sources for Concrete and Building Construction, IQS 45-1984”, Baghdad, Iraq, 1984. (In Arabic).
[7] American Society for Testing and Materials, “Standard Practice for Making and Curing Concrete Test Specimens in the Laboratory, ASTM C192.
[8] American Society for Testing and Materials, “Standard Test Method for Slump of Hydraulic-Cement Concrete, ASTM C143.
[9] American Society for Testing and Materials, “Standard Test Method for fresh density of concrete, ASTM C 138M-01.
[10] British Standard “Method for determination of compression strength, BS 1881: part 181.
[11] American Society for Testing and Materials, “Standard Test Method for splitting tensile strength of concrete, ASTM C496-04.
[12] American Society for Testing and Materials, “Standard Test Method for flexural strength of concrete, ASTM C 78-0.