Manual inspection and assessment method of highway bridges

Abstract

“Inspection and Assessment of bridges’' plays an important role, because the resources being spent in keeping existing bridges functioning to the standards for which they were designed are no longer sufficient. There is serious risk of reducing the investment necessary for rebuilding these structures. Since maintenance budgets are always limited, this involves setting priorities and defining maintenance strategies based on real condition of each bridge determined by periodic and proper inspection and assessment. In Sri Lanka we can see several types of bridges. Some of them are more than hundred years old. To decide whether the bridges need to be demolished or used for next few years, proper inspection methods and assessment techniques are needed. Based on the results maintenance can be carried out effectively. Not only for old bridges but new coming bridges also have to be inspected and evaluated on a regular basis and should be maintained to reduce the major repair cost. Current methods of inspection performed by Road Development Authority (RDA) of Sri Lanka are only visual inspection and it depends only on the personnel and it leads to some misjudgment. So, this research is made to improve the existing manual inspection method, with guideline and manual and propose new assessment method. The improvements on the newly developed manual inspection method consists new inspection sheets for condition inspection of concrete and steel bridges and guideline and manual for the manual inspection. This is basically an independent inspection method while comparing the existing method. The new assessment method for the condition assessment technique deals with equations to assess the component of bridges and main part of the bridges separately and overall assessment of the bridges. For the strength assessment of concrete deck slab “YIELD” software is validated. As there is no guideline for the assessment of bridges, assessment guideline also discussed. It is also recommended to carry on some additional work along the lines of present study.