b. Live loads

This type of loads refers to a generalized use of the bridge, this means the traffic flow and people walking, including braking, impact, collision and their dynamic loads. This category includes environmental factors such as rain and snow.

For reinforcing steel in concrete structures, the corrosion problem can be present

**Figure 19** shows a damaged pier due corrosion of the reinforcement steel, losing the coating and reducing the cross-sectional area, which means a reduction of the

On the other hand, if the structural steel is fully exposed to the environment without any humidity protection, the level of oxidation will be present on the entire element and will develop a generalized rusting reaction. **Figure 20** shows a struc-

Wear degradation during the life of a bridge occurs due its continuous use, where the friction is present by physical forces, including the pass of the vehicles over the main deck. These vehicles generate frictional forces when perform braking and accelerating, causing wear on the structure. For bridges where the piers are in

Usually traffic flow perform low wear degradation over the deck, however, if the road have any defect, will create bumps and wear will be increased rapidly, creating damages. Bridges using simply supported girders will require construction joints between supports; these joints are examples of places were bumps are easily created

when the rebar is exposed, oxidizing the area and develops structural problems.

mechanical capacity of the element.

*Bridges: Structures and Materials, Ancient and Modern DOI: http://dx.doi.org/10.5772/intechopen.90718*

**Figure 19.**

**Figure 20.**

**113**

tural steel bridge with all elements damaged by corrosion.

**6.2 Degradation due physical factors: wear and fatigue**

contact with water flow, the friction causes degradation.

*Concrete piers of reinforced steel with corrosion problems [18].*

*Bridge of structural steel with corrosion problems [19].*
