Conventional Reinforced Concrete

Reinforced concrete bridges suffer from corrosion of the reinforcement and, consequently, concrete degradation because of the high tensile forces exerted by 

Chloride-induced maorooell corrosion initiates on top rebar 

Expansion of corrosion product produces tensile stresses in concrete 

Tensile stresses in concrete lead to cracking/spalling 

Breakdown of the passive layer on the steel by chloride ions 

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The allowable support rotation and deflection for laced reinforced concrete has remained at 12 degrees. The increased allowable deflections for conventionally reinforced concrete will reduce... 

Most of these bridges are relatively new, and the overall economic impact is not as significant as for conventional reinforced concrete bridges. It is estimated that the... 

Conventional reinforced concrete bridges refer to those with superstructures made of reinforced concrete. In general, prestressed concrete and steel bridges will have... 

There are 543,019 concrete and steel bridges of which 78,448 are structurally deficient, leaving 464,571 bridges to be maintained for estimating purposes it is assumed that all these bridges have a conventionally reinforced concrete deck. The annualized life-cycle direct cost of original construction, routine maintenance, patching and rehabilitation for a black steel rebar deck costs between 18,000 and 22,000. These costs are both corrosion- and non-corrosion related. 

The containment is a prestressed reinforced concrete structure in the shape of a cylinder with a torispherical dome and a flat foundation mat. The cylindrical portion of the containment is prestressed by a post tensioning system consisting of horizontal tendons and vertical tendons. The dome is prestressed with crossed tendons that are anchored at the dome stiffening ring girder. The foundation mat is conventional reinforced concrete. 

The internal structures of the containment and other buildings of the nuclear island are conventional reinforced concrete structures. 

The application of any type of fibre in structural elements subjected to compression is infrequent, because the limited advantages do not counterbalance increased cost and more complicated technology. However, by the addition of fibres to conventional reinforced concrete columns, a moderate... 

The basic theory behind conventional reinforced concrete beam design is well known. Essentially, steel reinforcement is placed near the bottom of the beam and is used to carry the tensile stresses while the concrete at the top of the beam carries the compressive stresses. To avoid failure of this concrete in compression, the steel is actually underdesigned so that it will fail first. Thus, the concrete never reaches its ultimate capacity (5). 

Figure 14.1 Typical load vs. deflection curves of conventionally reinforced concrete and concrete reinforced with both steel bars and steel fibres [8].

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