By incorporating lightweight expanded polystyrene aggregate particles in a conventional highstrength concrete mixture, its density could be adjusted to any desired level. The adjusted density concrete can be expected to have reduced strength and stiffness the permeability of concrete would not be affected since the non-water absorbing polystyrene aggregate particles are dispersed randomly in a ...

Experiences in the development of Ultra High Performance Concrete found a very high flowability in concrete with low water powder ratio. Because of the high viscosity of the cement paste, compaction was necessary. To improve the compaction characteristics of the concrete the idea of adding coarse aggregate was developed. The first tests showed a good workability of the fresh concrete and a good...

This article examines the different failure modes of concrete sidewalks through an extensive field survey of sidewalk inventories in major cities in the Canadian Prairies. The major form of sidewalk damage is longitudinal cracks. There was no correlation of either the liquid limit or the plastic limit of the soil beneath the sidewalk with the type of sidewalk damage observed in each city. Howev...

Concrete cylinder piles produced by a centrifugally cast, vibrated, roller-compacted process have shown promising corrosion resistance in marine environments. Three bridges in the Florida panhandle with ~40 years in aggressive marine service and one newly constructed marine bridge utilizing concrete cylinder piles were examined. Examination of the older marine bridges showed minimal corrosion d...

The atomic polymer technology in form of mesoporous inorganic polymer (MIP) can effectively improve material durability and performance of concrete by dramatically increase inter/intragranular bond strength of concrete at nano-scale. The strategy of MIP is fundamentally different from most additives currently on the market for industrial applications. When MIP is added to a concrete or masonry ...

In this paper, a new roofing system is introduced, which is constructued using the precast composite sandwich panels. This roofing sandwich panels system consists of three kinds of precast concrete sandwich panels including capital panels, beam or between columns panels, and slab or middle panels. The panels are composed of three layers; A high strength reinforced concrete top layer. A thick la...

Flanged shear walls are used extensively in moderate- and high-rise buildings to resist lateral loads induced by earthquakes. The seismic performance of many buildings is, therefore, closely linked to the behavior of the reinforced concrete walls. They must be carefully designed to provide not only adequate strength, but also sufficient ductility to avoid brittle failure under strong lateral lo...