A survey of the existing structures to be retained on various road sites of the CP-1 road improvement scheme showed that the structures were showing signs of distress. It was therefore decided by the Engineers that a Non-Destructive Testing (NDT) programme be carried out to assess the adequacy of the existing structures to sustain the current traffic load and to identify any repair or rehabilitation work that may be required.
In order to perform the above tasks, Engineer asked the main contractor M/s. Hanbo Corporation to engage M/s. Engineering Consultants International (ECIL) (Pvt.) Ltd. as sub consultant / Subcontractor to carry out, an NDT survey of existing structures to be retained on various road sites of contract package-1 consisting of following road sections.
Sargodha - Talibwala Road (Three Structures)
Jhang - Chiniot Road (Three Structures)
Sambrial - Daska Road (Two Structures)
The original tasks were split into three phases:
Phase 1 comprised of the visit of the Senior Bridge Engineer in January 1998, for inspection of existing structures in the three road sites of CP-1, preparation of field investigation plans, coordination with the main contractor for making arrangement such as platforms for access to various structural elements of eight bridges.
Phase 2 the main work of NDT survey of the structures was conducted. A team of ECIL specialist carried out these tasks with special NDT equipments for different structural elements of bridges. The team remained in the field for one month period.
Phase 3 involved the evaluation of NDT test results based upon the data collected from field including visual inspection of structures.
This report presents the description of different equipments used for NDT survey, the photographs showing evidence of cracks and distress in different elements of structures, the summary of NDT test results and the recommendation for repair and rehabilitation of different structural elements.