Lightweight High Strength Concrete with Expanded Polystyrene Beads

This paper is a literature study about lightweight high strength concrete by incorporating expanded polystyrene beads. Basically polystyrene is disposal material from packaging industry. However, after being processed in a special manner, polystyrene can be expanded and used as lightweight concrete making material. Therefore, the use of expanded polystyrene beads in concrete is not only beneficial for engineering studies but also provide solution for the environmental proble

Collapsible high gain antenna

A lightweight small high gain antenna which is capable of being packaged in a collapsed form and automatically expanded when in use is described. The antenna includes a cylindrical housing having a rod with a piston adjacent to one end extending through it. Attached to the outer end of the rod in a normally collapsed state is a helical wire coil. When the gas producing means is activated the piston and rod are shifted outwardly to expand the wire coil. A latch is provided for holding the helical coil in the expanded position

Mechanical and durability performance of lightweight concrete brick with palm oil fuel ash (POFA)

Lightweight building materials such as precast roof and wall panel has been widely used in the construction industries. This is because lightweight materials could benefits the economy and society in terms of manufacturing, transportation and handling cost. One of the most preferable lightweight material is Expanded Polystyrene (EPS). EPS consist of 98% of air and 2% of polystyrene. Therefore, EPS is very low in density which could contribute in the reduction of building materials mass. Abundance of studies has shown that EPS has significantly contribute to the reduction of brick density. EPS has been used as the aggregates replacement in concrete. However, the existing of EPS in the concrete has reduce the strength performance of the concrete. Due to this, researchers have extend their research in improvising the EPS concrete and brick strength with the addition of pozzolanic materials such as fly ash, rice husk ask, silica fume and etc [1-4]. The ability of these pozzolanic materials in enhancing the strength of brick or concrete has been proven..

Corn cob lightweight concrete for non-structural applications

A lightweight concrete using granulated corn cob (without corn) as an aggregate is proposed in this research work. Taking into account that corn cob, after extracting the corn, is generally considered an agricultural waste, an interesting economic and sustainable benefit may result by using it as a building material. Therefore, it can be an alternative sustainable lightweight aggregate solution in comparison to the most currently applied ones such as expanded clay, particles of cork, particles of expanded polystyrene (EPS), among others. The density, the compressive strength and the thermal insulation properties of a corn cob concrete were experimentally quantified. An expanded clay concrete was also studied as reference. The main results obtained are presented and discussed showing that the proposed corn cob concrete may have the adequate material properties required for a lightweight concrete for non-structural application purposes

Structural performance of expanded polystyrene lightweight concrete (EPS - LWC) wall panel with square opening / Syed Nurfahmi Effendi Syed Abdul Malik

The load bearing wall is common construction for tall building. The lightweight expanded polystyrene wall panel was establishing in this study in order to develop as the load bearing wall. This study provide the expanded polystyrene lightweight concrete (EPS - LWC ) wall panel with square opening at the centre of wall panel. The objective of this study is to determine the ultimate axial load and maximum deflection of expanded polystyrene light weight concrete (EPS - LWC) wall panel. At the same time, this study also to evaluate crack behaviour of expanded polystyrene light weight concrete (EPS - LWC) wall panel with square opening. The material using to establish lightweight concrete wall panel are steel fibre and expanded polystyrene beads. The using of steel fiber is to minimize the major and minor crack around the opening. For the expanded polystyrene beads (EPS), it’s using to replace the coarse and fine aggregate to ensure the lightweight wall panel is establish. In this study were conducted two samples which are EPS - LWC wall panel with and without opening. The sample of EPS - LWC wall panel without opening is a control sample to compare with EPS - LWC wall panel with square opening. The result further confirm that the ultimate load of EPS - LWC without opening was 771 kN higher than EPS - LWC with square opening which is 428 kN. The deflection profile was not compliance the Euler’s rule because the wall was experience the maximum deflection at 1350 mm from the base of wall panel

Polystyrene cryostat facilitates testing tensile specimens under liquid nitrogen

Lightweight cryostat made of expanded polystyrene reduces eccentricity in a tensile system being tested under liquid nitrogen. The cryostat is attached directly to the tensile system by a special seal, reducing misalignment effects due to cryostat weight, and facilitates viewing and loading of the specimens

Efeito da pré-molhagem do agregado nas propriedades das argamassas com agregado reciclado deconcreto e agregado leve

This paper examines the suitability of partially replacing natural aggregate, sand, (NA) with recycled concrete aggregate (RCA) or lightweight aggregate (LWA) in mortars, under the hypothesis that pre-wetting aggregates would produce improvement in mortar properties. Fresh mortar properties such as density, entrained air content, consistency and heat of hydration, as well as hardened mortar properties such as dry density, compressive and flexural strength, and dimensional instability at 0% and 100% saturation were determined. The results show that mortars made with natural aggregate (75%) and recycled concrete aggregate (25%) have similar properties to mortars made with only natural aggregate (100%) and that pre-wetting the aggregates does not influence the properties of mortars significantly. Therefore, partial replacement with recycled concrete aggregate is a viable alternative for producing mortar.Peer ReviewedPostprint (published version

Lightweight SFRC benefitting from a pre-soaking and internal curing process

The presented research program is focused on the design of a structural lightweight fiber-reinforced concrete harnessing an internal curing process. Pre-soaked waste red ceramic fine aggregate and pre-soaked artificial clay expanded coarse aggregate were utilized for the creation of the mix. Copper-coated steel fiber was added to the mix by volume in amounts of 0.0%, 0.5%, 1.0%, and 1.5%. Test specimens in forms of cubes, cylinders, and beams were tested to specify the concrete characteristics. Such properties as consistency, compressive strength, splitting tensile strength, static and dynamic modulus of elasticity, flexural characteristics, and shear strength were of special interest. The achieved concrete can be classified as LC12/13. A strength class, according to fib Model Code, was also assigned to the concretes in question. The proposed method of preparation of concrete mix using only pre-soaked aggregate (with no extra water) proved to be feasible.Web of Science1224art. no. 415

Lightweight mortars containing expanded polystyrene and paper sludge ash

The objective of this research was to develop lightweight cement mortars with good thermal-insulation properties by incorporating expanded polystyrene (EPS) and paper sludge ash (PSA), both of which are problematic waste materials. The mortars formed had low thermal conductivity and low bulk density compared to control samples. Ground EPS produced lower thermal conductivity samples than powdered EPS. Resource efficient mortars containing up to 20% PSA, and 60% of EPS are considered suitable for use in rendering and plastering applications.The authors wish to thank the Spanish Ministry of Science and Innovation and European Union (FEDER) for project funding (BIA2007-61170), and the FPI scholarship (BES-2009-012166) award to Verónica Ferrándiz Mas which allowed her to develop her doctoral thesis. This research was carried out in the Civil and Environmental Engineering Department at Imperial College London, with funding from the Spanish Ministry of Economy and Competitiveness (EEBB-I-12-0574) to support Verónica Ferrándiz Mas