Applications
Every drop of water stored in our country’s reservoirs, water treatment plants, and behind dams is vital to the well-being of the population they serve and the local economy. This mission is even more crucial given that increasingly severe drought conditions have led to significant water loss in many parts of the U.S.
As for our country’s water treatment and wastewater treatment systems, communities need to be secure, knowing that none of the health-threatening stew held in these wastewater facilities makes it into local groundwater or nearby waterways. Likewise, we need to be confident that contaminants do not enter the clean water stored in our water treatment facilities.
What these containment applications have in common is that they all rely on concrete structures to keep water in its place, whether fresh or fetid. However, concrete shrinkage can lead to cracks, enabling water to escape or contaminants to enter.
Infrastructure Bill Leads to Expansion of Water Handling Sites
The long-time recognition of the deficiencies in this country’s water storage systems has led to the passage of the 2022 Bi-Partisan Infrastructure bill, which will enable more water treatment facilities and dams to deliver clean, reliable drinking water. And as for the water that comes from wells and waterways, wastewater operations will be more secure. Along with providing potable water, this bill will impact manufacturing, agriculture, and the economy.
The challenges for utilities are that new water/wastewater structures can face difficulties passing the required leak test and may require other expensive remedial work. These additional operations increase the cost of construction and can also extend project timelines, leading to delays and reduced owner/taxpayer satisfaction. In addition, decades of crack repair and maintenance represent a significant cost burden to the owner and headaches from taking a structure out of service while being repaired.
Ultimately, the cracking compromises the life cycle of the structure. For example, concrete that should have lasted 50-100 years forces the utility to perform replacement after only two to three decades.
The costly cycle of shrinkage cracks, repair, maintenance, and deterioration can be significantly improved using PREVent-C, the most effective admixture in mitigating shrinkage cracks and curling. Reducing or even eliminating shrinkage cracks means projects are completed on time, repairs are reduced, and lifecycle is greatly extended.
PREVent-C can be incorporated into the concrete for all water/wastewater structures, including reservoirs, primary and secondary treatment, clarifiers, aeration tanks, and digesters. In addition, PREVent-C is one of the only shrinkage reducers that is NSF-61 certified for use in potable water applications to make regulatory compliance easier.
There is a tremendous need for improvements in treatment facilities to process drinking water and wastewater across the country. These are some examples of water containment projects that controlled the problem of concrete cracking by adding PREVent-C to their concrete mixture.
Updating an Almost 60-Year-Old Water Treatment Plant
Winston-Salem/Forsyth County Utilities has begun construction on the Neilson Water Treatment Plant project. It is the largest in the WSFC Utilities System, with a treatment capacity of 48 million gallons per day (MGD). Since WSFC built the original plant in 1964, the facility has undergone two capacity expansions of 12 MGD each in 1984 and 1988. This upgrade will address aging infrastructure by replacing obsolete, failing equipment and making process improvements to increase the reliability and redundancy of this critical facility.
Black & Veatch, the engineer for the project, specified concrete with a 0.035 percent shrinkage limit for the project. Argos, the Ready-Mix supplier, worked closely with Terracon, an engineering consultant, to develop a mix design to satisfy the requirements needed.
After initial trial batches did not meet the specification, a standard Shrinkage Reducing Admixture (SRA) was evaluated. After once again failing to meet the specification, PREVent-C technology was used. The results from using PREVent-C technology exceeded the specification.
Expanding Wastewater Plant to Reduce Local Overflows
Expanding the wet weather treatment capacity by enlarging existing plant facilities has been a cornerstone in the Allegheny County Sanitary Authority’s (ALCOSAN) strategy for reducing sewer overflows for over the past 25 years. This stormwater runoff has been one of Pittsburgh’s most intractable problems.
ALCOSAN’s $2 billion Clean Water Plan includes building the new East Headworks facility. This new plant will increase ALCOSAN’s wastewater treatment capacity from 250 MGD to 600 MGD. The contractor drilled over 1,900 auger cast piles into the bedrock to serve as the support system for the plant.
Whitman, Requardt & Associates, LLP (WRA), the engineer for the project, had concerns with shrinkage and potential related cracking on the project during the design stage. The structural concrete is heavily reinforced, putting the concrete under serious restraint from movement.
Additionally, the proximity to a nearby river added concerns about shrinkage cracking, leading to contaminants reaching the river. As a result, WRA specified a Shrinkage Reducing Compensating Admixture for the concrete. PREVent-C technology was selected as the basis for design, significantly reducing the cracking problem.
The Infrastructure Bill directs billions to projects such as these for necessary improvements. Using PREVent-C admixture will enable these structures to minimize cracks in the surface of these concrete structures to maximize these investments and ensure these facilities meet the needs of their localities for decades to come.
Put it to the Test
Order a sample of PREVent-C and schedule a trial mixture to evaluate its effectiveness on shrinkage cracking, as well as its effects on other fresh and hardened concrete properties. Or, send us your general questions about accelerated concrete construction. Contact PREVent-C experts today.
