Copyright © 2018 Authors. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. International Journal of Engineering & Technology, 7 (2.29) (2018) 927-932 International Journal of Engineering & Technology Website: www.sciencepubco.com/index.php/IJET Research paper Effect of Curing Method on Properties of Lightweight Foamed Concrete Bishir Kado 1 , Shahrin Mohammad 2 *, Yeong Huei Lee 3 , Poi Ngian Shek 4 , Mariyana Aida Ab Kadir 5 1,2,3,5 Faculty Of Civil Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor, Malaysia. 4 Construction Research Centre (UTM-CRC), Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor, Malaysia. *Corresponding Author E-Mail: Shahrin@Civil.My Abstract Lightweight construction is aimed to achieve a sustainable feature by reducing transportation frequency and construction materials usage during construction phase. Lightweight precast concrete may serve an alternative for the lightweight construction. There are rarely application can be found for structural members as lightweight panels always to be used for secondary or non-load bearing members. This paper presents an experimental study on properties (compressive strength, splitting tensile strength, water absorption) of lightweight foamed concrete (LFC) at two different curing methods. LFC with densities of 1500, 1700, and 1800 kg/m 3 , cement- sand ratio of 2:1 and water-cement ratio of 0.5 were investigated. The results showed LFC can be produced with the properties of density range of 1500 to 1800 kg/m 3 and corresponding compressive strength of 10 to 39 MPa. The higher the density of LFC, the less the water absorption for all the curing method considered, the highest and the lowest water absorption was 11.3% and 2.0% for 1500 kg/m 3 cured in water and 1800 kg/m 3 cured in air respectively. Compressive strength of LFC increases with age and density while water cured LFC has high compressive strength. Splitting tensile strength increases with density of LFC, but air cured LFC has more splitting tensile strength than water cured of the same density. The highest splitting tensile strength recorded was 3.92 MPa for 1800 kg/m 3 cured in air, which was about 16% of its compressive strength at 28 days of curing age. These properties are important and can be applied to LFC precast structural members with air or water curing method which have less references for LFC in structural usage. Keywords: Lightweight; foamed concrete; curing; density; strength 1. Introduction One of the advantages of lightweight concrete in construction pro- jects is to reduce the self-weight of the concrete structure; thereby reducing the size of the structural members such as columns, beams, foundations and other load bearing members [1]. Foamed concrete is an aerated light-weight concrete produced by mixing cement, sand and water to form cement paste, the cement paste then mixed with pre-formed stable foam produced from foam generator. Foamed concrete can be designed to have any density within the range of 300 – 1850 kg/m 3 dry density [2]. Lightweight foamed concrete (LFC) were commonly used for void filling, roof insula- tion, trench reinstatement, bridge abutment, thermal insulation, road and pavement sub-bases, precast blocks and panels [3]. Light- weight, ease of fabrication, durability and cost effectiveness are some of the advantages of LFC that attracts a lot of attention from industry [4]. Lim et. al. [5] presented other advantages such as excellent thermal and sound insulation, low density, self-compacting, and high flow ability made LFC commonly used for structural and non-structural purpose by construction industry. Mydin [6] studied the possibility of using LFC in load bearing composite wall panels for low rise structure. The result showed that it is possible to design composite walling system to resist floor loads using LFC in a low rise residen- tial structure. Investigations on strength of composite sections with foamed and lightweight concrete was conducted on circular and square concrete filled steel tube columns and simply supported short beams. The result shows that LFC contribution to squash load is insignificant, while its contribution to the flexural strength is sig- nificant [7]. A lot of studies were carried out on LFC and its application, but very few researches are available on structural LFC and its applica- tion; as such the properties of structural LFC need to be investigated thoroughly. The purpose of this paper is to presents the study on properties of structural light weight foam concrete at different cur- ing method. When LFC is being used as an infill material in com- posite structures, in most cases, it is not possible to cure the LFC with water (for example in concrete filled steel tube columns). Therefore, LFC properties cured in water and Air need to be ex- plored. Experimental investigations were carried out on 1500kg/m 3 , 1700kg/m 3 , and 1800kg/m 3 LFC densities at 2:1 cement-sand ratio and water-cement ratio of 0.5. 2. Previous Investigation on Structural Prop- erties of LFC The amount of air content in LFC, resulting from mixing with foam, significantly affect the strength and other properties. LFC gained a lot of popularity in some countries like Japan, United Kingdom and Europe [8]. Lightweight concretes have been classified based on its properties [9], the classification is presented in Table 1. Table 1: Classification of light-weight concrete based on concrete proper- ties