ICPI Initiates Research into the Use of Open-Graded Bases Under Sand Jointed Interlocking Concrete Pavement

The ICPI Foundation for Research and Education has approved funding to investigate the performance and limits of the use of open graded bases and bedding under standard interlocking concrete pavement with sand filled joint.

The Foundation has an agreement with Englobe of Kitchener, ON to complete this multi-phase research.

Phase 1: Initial meeting and literature review of current methods to reduce migration of fine materials from one medium to another. Using the literature determine the available local materials and select 6 materials to use in the lab trials.

Phase 2: Gather samples of each of the six (6) selected materials and test in the lab for gradation. Further testing will include creation of 500 mm (10 inch) by 500 mm (20 inch) plexiglass boxes. Up to nine test sample combinations will be placed in the boxes and tested on a vibration table to determine migration of fines and settlement of pavers placed at the surface, samples will be tested dry and with “rain” cycles. Water outflow will be tested for material loss; GoPro video of samples during testing will be taken for review. Lab trials to be conducted at Englobes facilities in Kitchener, ON.

At the end of phase 2 the results and recommendation from Englobe will be reviewed by the Foundation Program Committee and the task group overseeing this project to determine which assemblies to be constructed in phase 3.

Phase 3: Field Trials will include supervision of construction for up to 2 days as well as evaluation of the Pavement Condition Index at initial construction, one week, 2 weeks, 3 week, 4 weeks, 2 months, 3 months, 6 months, 9 months, 12 months and 2 years after construction. The field trials constructed will include three (3) different material combinations with two (2) different loading conditions. The loading conditions will be pedestrian traffic, light-duty vehicle traffic with sharp turning movements. Costing assumes one onsite field investigation of a failed area to determine root cause of the failure.

Great North Hardscape of Cambridge ON has provided space at their facility in Cambridge ON to conduct the full scale field tests.

ICPI will be looking to members to donate the pavers and other materials that will be used in the construction of the test sections. If you are interested in being considered, please contact Robert Bowers (rbowers@icpi.org) to make sure your name is on the contact list when the call for materials goes out.

Reba Miller