This paper describes the SHRP-NL research program, the initial phase of the project and linkage to SHRP-USA. In essence, The Netherlands Strategic Highway Research Program SHRP-NL involves Long Term Pavement Performance (LTPP) studies on some 200 test sections throughout the Netherlands. Taking into account that the Netherlands has only one climate zone (as opposed to the four zones dealth with in SHRP-USA) and that the SHRP-NL program only involves studies on asphalt concrete pavements, the number of test pavements corresponds well with the 1600 test sections included in SHRP-USA. This correlation follows directly from the use of the SHRP-USA system for experimental design in setting up SHRP-NL. The major part of the test sections involved in SHRP-NL, are GPS-sections, which are monitored for their performance using Visual Condition Surveys and Falling Weight Deflectometer Tests. A limited number of SPS-sections is included to study maintenance effectiveness. The SHRP-NL LTPP-program is structured to be an independent experiment with a sufficiently large number of test sections to deal with the specific Dutch research needs. On the other hand, there is sufficient overlap with the LTPP-project of SHRP-USA to ensure a proper exchange of research findings. The first phase on SHRP-NL involves the selection of the 200 test sections needed. From an initial set of 300 candidate sections submitted by the various road authorities, a first selection was made on the basis of the experimental design. Each of the cells in the three main experimental tiers was filled with at least two test sections, preferably selecting pavements covering the extremes within the particular cell. The sections thus selected had a length of typically 1-2 km. On these sections, LaCroix deflectograph measurements were performed to obtain homogeneous 300 m sections, which will be the final SHRP-NL test sections. The LaCroix deflectograph was used for these inventory measurements rather than FWD-equipment because of the much higher density in measurements obtained with the LaCroix. In the remainder of the project, Dynatest FWD-equipment will be used for deflection measurements. (A)
Abstract