Funktionskrav på vägars bärighet

Sammanfattning: The Swedish Transport Administration procures performance contracts to increase the attractiveness of the construction industry. In this procurement, The Swedish Transport Administration has transformed technical solutions into functional requirements. This allows the contractor to develop his own technical solutions. As a customer, The Swedish Transport Administration needs to find out the quality of the product that is delivered. The quality can be investigated through a load bearing capacity control. In this master's thesis, the concept of load bearing capacity is used to describe the road structure's ability to receive loads from traffic before failure. The client has developed a test of bearing capacity to determine whether the road will last during its entire lifespan. The control requirements are in the form of a falling weight deflectometer performed during the minimum guaranteed instruction period. Implementation requirements exist today, however the monitoring of the measurement results are missing since there is no required limit to be met by the control. In this thesis, the conditions and consequences of using traditional Falling Weight Deflectometer (FWD) as a functional requirement is investigated. Should demands be made on the bearing capacity in a design, construct and maintain contract? In this case, what kind of measurement should be used? The thesis has been carried out by analyzing three different study objects to evaluate if FWD measurements are applicable to all different types of roads. Interviews have also been conducted to get a deeper understanding on the subject and problem area. The conclusions that can be drawn are; Demands on the load bearing capacity should be made because performance requirements on load bearing capacity is the only way to check if the delivered road will last the entire design period. If the measurement is performed according to the method description, there should be no uncertainties in the measurement results. The study objects show that control requirements with a Falling Weight Deflectometer (FWD) measurement can be used on all types of roads, but the method needs to be adjusted for roads with shorter distances. Measurements that are beneficial to use in reporting/documenting load bearing capacity are SCI, BCI and subgrade modulus. The SCI to be used to control the surface course and binder course, BCI to control the structure of the base course and sub-base course and the subgrade modulus to control the structure of the terrace. With the conclusions above recommendations have also been made to follow up the work.