Colorado DOT – Shopping Center Egress
The Colorado DOT used EdenCrete® in the egress of a new shopping center, comparing the strength, finishing operations, and durability against that of a topically-applied finishing aid.
EdenCrete® was used as an alternative to the finishing aid in only 2 select areas of the egress, and the finishing aid was used for the remainder of the placement. The locations for the EdenCrete® were deemed to be the most aggressive and heavily trafficked. EdenCrete® improves the ability of concrete to be placed and finished, as well as the durability against moisture ingress and abrasion from vehicle traffic.
The Colorado Department of Transportation (CDOT) placed the egress for a large shopping center using concrete. Heavy vehicle traffic cause abrasion and cracking, while aggressive winter conditions can cause rapid deterioration of concrete from the ingress of moisture, chlorides, deicer chemicals, etc. To mitigate surface abrasion and to improve the durability of the concrete surface, the engineer specified a topically applied, finishing aid, to densify the surface and extend the service life. Finishing aids can be effective if maintained and reapplied annually, but the added cost of topical application during and after concrete placement perpetuates maintenance costs from year one. As it pertains to strength, finishing aids are only effective in strengthening the top 1/8” of the concrete, leaving the overall compressive strength unaffected.
Concrete ProducerBrannan Ready-Mix
Location/DateLafayette, CO, February 2018
ContractorThoutt Bros. Concrete Contractors, Inc.
Volume & Dosage
The project involved 20 cubic yards if concrete, 10 yards each with 1 and 2 gal/yd3
Project Details and Conclusions
The crew commented that placement and finishing operations went equally well for both the EdenCrete® sections and the sections having the finishing aid applied on top. However, they were not pleased with the added time and labor to apply the finishing-aid, stating that it slowed down the schedule and was an expensive hassle.
To date, the EdenCrete® sections in the field are performing very well against the sections having the finishing-aid. The EdenCrete® sections are abrading minimally, while the sections with the finishing-aid have abraded significantly more after the same amount of time in service. Because the finishing-aid will likely not be reapplied according to manufacturers recommendations, it is anticipated that the concrete durability for the sections covered with the finishing-aid will begin to deteriorate exponentially as time goes on. As this occurs, we anticipate the EdenCrete® sections to further outperform the finishing-aid beyond what has already been demonstrated to be significant.
Lab testing was run in parallel to quantify the improved performance between mixes. EdenCrete® at 2 and 3 gal/yd3 improved compressive strength over the Reference by 13 and 20%, respectively, while the finishing-aid provided no improvement to strength over the Reference. At 2 and 3 gal/yd3, EdenCrete® improved the resistance to abrasion by 20 and 36%, respectively, over the Reference. The finishing-aid improved abrasion resistance by ~8% over the Reference. Lab testing demonstrated the ability of EdenCrete® to improve the concrete strength and resistance to abrasion.
Finishing-aids require a schedule of reapplication in order to maintain effectiveness for the life of the concrete. If not maintained, finishing-aids will wear off and leave the untreated concrete surface exposed to wear. Essentially, if the owner does not continue to reapply the finishing-aid they will lose their investment within a couple years. This perpetuates annual maintenance costs for the life of the concrete if the owner would like to maintain protection against the elements. Unfortunately, this detail is not often conveyed well to the owner and they do not understand what is required to properly maintain the protection provided by the finishing-aid.
EdenCrete® is dosed integrally and at the plant during batching, so there is no additional labor cost for it to be used and it is effective throughout the entire concrete mix. Pumping, placement, and finishing operations are easier than with traditional concrete. There is no annual maintenance required for EdenCrete® to remain effective, and it performs from the time of batching and throughout the life of the concrete.
The project involved 20 cubic yards of concrete, 10 yards each with 2 and 3 gal/yd3.