When one of the Tennessee Concrete Association’s ready mix members reported that the permits for its new batch plant required it to install about 500 cubic yards of pervious concrete, TCA Executive Director Alan Sparkman elected to capitalize on the opportunity. As a result, TCA is partnering with Middle Tennessee State University (MTSU) to take advantage of the potential data that can be generated on the project, reports NRMCA Senior Director, Local Paving, Phil Kresge.

 

"This project presents an excellent opportunity for testing of admixtures, fibers or other materials in pervious concrete mixes to measure how such materials affect, and hopefully improve, pervious concrete performance," Sparkman said. In addition to the field testing during initial installation, MTSU will also conduct freeze/thaw and deicer testing on one portion of the installation over a one-year period to test how products or mix designs perform under these conditions. Placement of the concrete began in early June and will be completed in two to three weeks.

Monitoring and testing of the concrete through the first year will be coordinated by Dr. Heather Brown, associate professor and department chairman of MTSU’s Concrete Industry Management (CIM) program. As part of the study, a minimum of two deicers will be chosen for investigation - MgCl and DOT brine solution - though others may be considered. Deicer treatment will be applied during all proposed inclement weather throughout the winter season. No cleaning of the deicer will occur after it has been applied and once the weather pattern has passed, to allow for maximum damage. Chloride samples will be removed from the concrete using a revised version of ASTM C1543 - 10a: Standard Test Method for Determining the Penetration of Chloride Ion into Concrete by Ponding, and will be tested with ASTM C1152: Acid Soluble Chloride. Scaling will be determined based on ASTM C672/C672M – 12: Standard Test Method for Scaling Resistance of Concrete Surfaces Exposed to Deicing Chemicals. Cores will be extracted and split in tensile to determine both strength and depth of penetration of deicer attack. 

Sparkman expects that initial publication of results from testing and a summary write-up of the project will be available by September 1.