ICPI Conducts Load Tests for Permeable Pavers

Wednesday, February 5, 2014
UC Davis PICP Test Track Progress Report February 3, 2014

In an effort to develop better design tools for permeable interlocking concrete pavement (PICP), the University of California Pavement Research Center in at UC Davis is preparing to load test 2,600 sf PICP test track with a heavy vehicle simulator. In a matter of months, this machine can rapidly apply 25 to 200 kN wheel loads (5600 to 45,000 lb) that simulate years of truck traffic. This test track is the first of its kind in the western hemisphere. The PICP test track includes 80 mm thick pavers with permeable jointing stone, 50 mm thick bedding stone over 100 mm of ASTM No. 57 stone. The subbase thicknesses varies between 450, 650 and 950 mm and these are on a weak clay subgrade. The pavements are instrumented with pressure plates on the soil subgrade and under the bedding layer to measure how stresses from the wheel loads are distributed.

UC Davis Test TrackUC Davis Test Track - 2

This information will provide key information in modeling and development of base thickness charts for various soils and wheel load conditions. The full-scale validation should provide needed assurance on PICP performance to civil engineers, especially performance in saturated soils. Load testing should take about four months.

The project is funded by paver producers from California including Angelus Block, Orco Block, Oldcastle, Basalite, RCP Block, Olsen Pavingstone, Air Vol Block, Pavestone, Pacific Interlock, Calstone, and Acker Stone. Additional support is from the California Nevada Cement Association and from the ICPI Foundation for Education and Research. Material donations included 2,640 sf of permeable pavers from Basalite, a roll of geotextile (5000 sf) from Tencate Mirafi, and a loan of a new Weber CR7 60 kN (13,500 lbf) plate compactor with a compaction indicator from WeberMT. Also donated was stiffness testing of the soil, subbase, base, and pavers by Kessler Soil Engineering Products using a lightweight falling weight deflectometer.