Utförandets inverkan på hållbarhet för beläggningslager

Safwat F. Said
Thomas Lundberg
Carl-Gösta Enocksson

Non-destructive testing in quantifying the asphalt pavement layers homogeneity can be used for the quality assurance in paving contracts. This paper summarizes the findings from a field study on segregation in bituminous pavement mixes that relates pavement layer surface texture to the homogeneity of the paved bituminous layer by distinguishing mix segregated area. The mean profile depth (MPD) values of paved layer were measured. Based on these values three locations on the road were identified having low, intermediate and high MPD values. Thereafter, cored samples were tested for stiffness modulus before and after moisture conditioning by performing the moisture induced sensitivity test (MIST). Results clearly showed that the samples from the locations with high MPD values were mostly affected by the moisture conditioning for which the stiffness moduli were significantly reduced. The samples with high MPD values had the highest air voids as well. Thus, this study demonstrated that construction quality described by segregation in the paved asphalt mix has a significant impact on the moisture sensitive performance of pavements. A limited number of falling weight deflectometer (FWD) measurements were performed at positions with different degree of separation in the road base layer. There was a tendency for the effect of separation in the road base layer on FWD even though there was a variation in data. The strong correlation between the MPD values and change in stiffness modulus also suggests that the measurements of the MPD values can be a reliable and non-destructive method for evaluating the construction quality of a pavement and in developing the quality assurance criteria based on pavement performance that can be used in paving contracts.



Global Public Transport Summit

On 9-12 June 2019, the international public transport community, mobility decision makers and industry suppliers will come together in Stockholm for the UITP Global Public Transport Summit. VTI will be represented in the conference exhibition.

European Road Profile User's Group, ERPUG

Welcome to the sixth ERPUG meeting in Vilnius, Lithuania. 

Vision Zero for Sustainable Road Safety in the Baltic Sea Region

The second Vision Zero for Sustainable Road Safety in the Baltic Sea Region conference will be held in Tallinn, Estonia. VTI is part of the programme committee. 



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