Lightweight concrete (LWC) is a kind of concrete that made of lightweight aggregates or gas bubbles. These aggregates could be natural or artificial, and expanded polystyrene (EPS) lightweight concrete is the most interesting lightweight concrete and has good mechanical properties. Bulk density of this kind of concrete is between 300-2000 kg/m3. In this paper flexural strength of EPS is modeled...

In this paper, the effect of Polypropylene Fibers added to concrete on strength and thermal resistance of high strength concrete has been investigated. Therefore, five tests have been carried out to reach this goal which it includes; effect of weight percent of polypropylene fibers on mechanical properties of concrete, effect of fiber’s length on the strength of high strength concrete, effect o...

self compacting concrete (scc) specimens with limestone (l) and quartz (q) powders were formulated. the influence of the type of the powder on the properties of fresh and hardened concrete was evaluated. dense packing theories were used for mix design of samples. the equation of fuller and thompson for particle size distribution (psd) of aggregates was modified with considering fine particles a...

In this study, the elevated temperature flexural strengths of lightweight foamed concrete (LFC) containing fly ash (FA) and polypropylene fiber (PF) was investigated experimentally and statistically. The variables included were the temperature degrees (in a range of 20 to 600°C), LFC densities of 600, 800, 1000, 1200 and 1400 kg/m3 and additive content. Two mixes were made by replacing 15% and ...

Steel-concrete-steel (SCS) sandwich panels are composed of two steel plates with low thicknesses and high densities and strengths and one thick layer between both plates with low strength and density known as core that is composed of concrete. Cohesive material-epoxy resin or shear connectors are usually used to connect the plates to the concrete core. SCS sandwich composites are being develope...

this paper describes a methodology in designing high-performance concrete for simply supported beams, using a hybrid optimization strategy based on a variable neighborhood search threshold acceptance algorithm. three strategies have been applied to discrete optimization of reinforced concrete beams: variable neighborhood descent (vnd), reduced neighborhood search (rns) and basic variable neighb...

INTRODUCTION Porous concrete, especially Aerated Autoclaved Concrete (AAC) was first developed by a Swedish engineer between the years 1920 and 1932 [1]. He was searching for a material with the properties of wood, but without the disadvantages of wood. Near the end of World War II, AAC became widely used. Vast areas of cities and industries lay in waste and tremendous rebuilding became necessa...