Before 1992 the Swedish Road Administration (SRA) carried out all bridge maintenance and minor repair for all bridges in Sweden by themselves. The bridge maintenance crew in a county consisted typically of 3-6 workers and a bridge-engineer.
SRA and some contractors suggest that it could be a good idea for SRA to procure bridge maintenance in one or two counties for a long-time, e. g., seven to ten years. The bridge maintenance crew could be a model for this.
The aim of the research project is to present an updated model for procurement of bridge maintenance based on functional requirements. The base for this updated model will be the findings and conclusions that could be drawn from a real project – a case study. The research project shall continuously follow-up the performed maintenance and document how the contractor is planning and performing the work. The research will specially focus on measurable verifying methods for the performed maintenance. The results from the research project will be evaluated and compared with standard maintenance methods and the results will hopefully be used to update current regulations. The hope is also that the contractor will develop new and effective maintenance methods with the larger freedom a functional contract enables. At the end the final goal is to reduce the cost for the society for bridge maintenance in the future.
The basic idea behind performance contract is that the client makes measurable functional demands with regard to the finished product, instead of presenting technical solutions. As an example the client could demand a certain friction and smoothness for the road surface. These functional demands should be formulated so that they have a direct relevance for the safety and flow of traffic.
It is important that these functional requirements are divided into a target level and an absolutely lowest possible level (acute level). A contractor should maintain the target level both as an average functional level during the contract period and when the contract is completed. For the acute level there should be stipulated a maximum allowable time before corrective action needs to be taken.
The methods that have been used in the research project are interviews, meetings, literature studies, reports, follow-up, statistics, participating in seminars, the authors own inspections, annual reports and so on.
Since the author didn’t find anything published about bridge management on performance contract, to the author’s best knowledge, the literature studies have been concentrated on nearby topics, e. g., highways on performance contract and bridge maintenance in general et cetera.
The research project has so far consisted mostly of a pilot study. From the beginning the idea behind the project was:
• To procure bridge maintenance for the small and mid-sized bridges,
• in one or two counties,
• for a longer time, e. g., seven to ten years.
• The value of a maintenance contract could be in the range of about 100 MSEK for the whole time.
Since this is the first project of its kind in Sweden the owner (SRA) did not dare to let this pilot project be too voluminous. What will be tested and followed by this research project is to use contracting for maintenance based on functional requirements for all 400 bridges in Uppsala County in Sweden and for a period of three years and with an option for three more years. Uppsala County is situated some 20 km to 200 km north of Stockholm.
To summarise the actual contract:
• A contractor should perform bridge maintenance for all 400 bridges in Uppsala County.
• The contract was three years (1 Sept. 2004 – 31 Aug. 2007) with an option for three more years (1 Sept. 2007 – 31 Aug. 2010).
• The bridges were deemed to be in satisfactory condition if the contractor verified that they met the functional requirements in SRA’s regulations once a year.
• Repair of 25 bridges during the contract’s first three years.
• If the option for three more years will be used, then there will be some additional bridge repairs.
• The contractor was expected to contribute in the research project.
There were six contractors that requested the tender documents, but only three of them submitted an offer to SRA, see table below.
Contractor Submitted offer
Vägverket Produktion 20 387 943 SEK
DAB-Domiflex AB 23 728 040 SEK
NCC Construction 28 620 000 SEK (Advance 2 000 000 SEK)
All of the three contractors deemed to have met the standards of a contractor set by SRA. Vägverket Produktion (VP) was the lowest bidder and therefore it was contracted by SRA for this project.
Interviews were carried out with all six contractors that had requested tender documents. All of them thought that a multiyear bridge maintenance contract was an interesting idea. Large companies tend to want large contracts and small companies tend to settle for smaller contracts. All of the contractors thought that it was easy to calculate the 25 bridge repairs compared to bridge maintenance on functional demands.
According to the contract VP should repair 25 bridges during a three year period. VP divided these repairs in three equal parts: nine bridges 2005, eight bridges 2006 and eight bridges 2007.
The functional requirements for the bridges should be verified once a year according to the contract. Both representatives for SRA and VP carried out bridge inspections during the first year and it was noted that the representatives had a different view on some of the discovered defects on the bridges. The representatives had a different view mainly on the bridges’ structural members’ slope and embankment end, edge beam and surfacing. It is important to specify how to measure and interpret the results from inspections regarding defects in functional requirements. Defects in functional requirements should be divided into acute defects and non-acute defects. Acute defects needs to be more precisely defined but could be surfacing against bridge, settling in slope and embankment end and flushing.
These defects should be rectified as soon as possible. Non-acute defects could be rectified when there is enough work for the contractor to carry out but not later then October 31st every year. The research project will continue to follow-up and evaluate the first three years of the pilot study.
The research project will also follow-up and evaluate if the option for extending the contract three more years will be used. According to the contract, if the option will be used, there need to be a meeting between the client and the contractor not later than 31 Aug. 2006 and a settlement need to be reached not later than 30 Sep. 2006.
It is of interest to study the possibility to use, in future tender documents, the indicator Lack of Capital Value and/or the average permissible level of defects in functional requirements for the bridge stock. Further research should also be focused on how defects on different members of the bridge evolve and the cost associated to rectify them. It is of interest to know how many defects that are evolved during a normal year for the 400 bridges in the study. If one knew the number of defects one can estimate the costs to rectify these. The estimated cost can then be included as information for the potential contractor in future tender documents.
So far SRA’s representatives are satisfied with the project and with the good relationship that evolved between SRA and the contractor. SRA is also satisfied with the increased focus on the bridge functional requirements.
If this project will continue to show good results then SRA will consider procure bridge maintenance on similar contracts for more counties.
Stockholm: KTH , 2006. , xix, 163 p.