Bridges, service lifes

Several examples of application are given in the literature [40], e. g. for predicting the residual service life of a corroding bridge and testing the efficiency of protection with a corrosion inhibitor [44]. 

Thermally sprayed soluble coatings of zinc or aluminium (or their aUoys) are also used. Practical experience exists in the USA, among others, on bridges. Another sacrificial system is based on a zinc foil attached to the concrete surface via an ion-conducting gel adhesive [52-54]. Sacrificial CP systems have obvious advantages of simplicity and ease of application the main questions concern their effective service life. 

Maintenance To detect failure arising during the service life of a product. This failure detection function can be seen in inspection of road and rail bridges for structural determination or of civil airlines for stress cracks or corrosion (see below). 

Research conducted in the UAE highlighted that the service life of reinforced concrete is significantly lower than in other parts of the world [15]. The service life of some typical structures is 35 years for offshore structures, 50 years for structures designed according to international and national codes, and 100 years for bridges and tunnels [16]. The harsh enviromnent (high temperature and humidity), the poor concrete quality, and the poor workmanship in the UAE are considered to be the main factors that are responsible for the rapid deterioration and aggressive corrosion of structures. This results in the short service lives of the structures constructed in the UAE. 

Sohanghpurwala, A.A. (2005). Manual On Service Life of Corrosion Damaged Reinforced Concrete Bridge Superstructure Elements. NCHRP 18-06A Final Manual. 

Weyers, R.E., Fitch, M.G., Larsen, E.P., Al-Qadi, I.L., Chamberlin, W.P. and Hoffman, P.E. (1994). Concrete Bridge Protection and Rehabilitation Chemical and Physical Techniques - Service Life Estimates, Strategic Highway Research Program, SHRP-S-668, National Research Council, Washington, DC. 

Concrete Bridge Protection and Rehabilitation Chemical and Physical Techniques—Service Life Estimates. Pre.sents definitions of end of service life of reinforced concrete bridge components exposed to chloride laden environments categorizes corrosive environments and defines end of... 

Life-cycle cost. The expected service life of the composite deck exceeds 75 years with little maintenance this is about three times the expected life of a concrete bridge deck. 

Projections for anticipated vessel traffic during the service life of the bridge should address both changes in the volume of traffic and in the size of vessels. The following factors need to be considered ... 

Criteria for tolerable foundation settlement shall be established consistent with the function and type of the bridge structure, anticipated service life, and consequences of unacceptable movements on structure performance as outlined by AASHTO (2012). As discussed earlier, the criterion adopted by AASHTO (2012) considering the angular distortion (8/1) between adjacent footings is as follows ... 

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