Agileflow® Self-Consolidating Concrete Provides Shelter from the Storm in Tornado Alley

10.27.2021

As the northward expansion and exponential growth of the Dallas-Fort Worth metroplex continues with no end in sight, the city of Anna is certainly feeling the impact. Located 42 miles north of Dallas in Collin County, Texas—our nation’s sixth-fastest-growing county—the up-and-coming city of Anna is one of the five fastest-developing communities in North Texas.

While an increase in population density brings many benefits in terms of economic and opportunity growth, it also comes with certain challenges—especially considering this area of North Texas is situated in “tornado alley”. Architects must design emergency operations centers that not only offer superior protection against high winds and flying debris during severe storms but also continue to function—often at increased capacity—after catastrophic events. High-performance concrete storm shelters are especially suited to provide critical structural resilience and ensure that community

 

The Challenge

Due to Anna’s rapid development over the past several years, the construction of a new municipal complex with expanded fire and police facilities was deemed a strategic next step for improving public safety. To this end, the city set out to develop a new municipal complex that would include a stand-alone 15,800-square-foot central fire station and command-and-control center to serve as a safe room for emergency management professionals to coordinate disaster-response efforts.

One of the greatest challenges during the construction of this critical high-performance building was finding an ideal concrete solution that would perform on a variety of levels. The use of conventional concrete was not possible, because the structure’s atypical shape and heavy reinforcement within the 16-inch walls did not allow for easy product placement and vibration. The project team needed an innovative, high-strength concrete mix that would flow through easily and firmly self-consolidate around the highly congested steel rebar in the uniquely tapered core walls, where vibration was not an option.

The Solution

To meet the demanding performance criteria and to expedite pouring work on the complex cast-in-place concrete walls, Sizelove Construction relied on Agileflow, a high-strength self-consolidating concrete (SCC) product. Topping the list of benefits attractive for the project were Agileflow’s easy-to-place and very fluid nature, and the ability of this advanced SCC mix technology to accelerate pouring work as the concrete flows and spreads effortlessly through heavily reinforced formwork without vibration. Additional advantages of using Agileflow included superior nonsegregation properties for greater structural integrity and high-quality architectural finishes on the exposed surfaces.

Based on local raw-material assessments and rigorous quality-control testing, Lattimore Materials developed a customized Agileflow SCC mix to achieve the superior flow, optimal bonding strength, low shrinkage and high-strength requirements for constructing the challenging high vertical walls. Key concrete performance targets included a 27-inch spread and 6,000-psi compressive strength at 28 days.

The Results

Now complete, the new resilient central fire station and emergency management center will allow the city of Anna to remain true to its commitment of providing reliable response services to meet the growing needs of the community.

For the project team, the customized high-strength Agileflow mix was the ideal solution for meeting the demanding construction, durability and quality goals for the building. The product performed exceptionally well in spreading throughout the congested formwork and consistently surpassed the specified 6,000-psi strength requirement.

“Due to its superb self-consolidating properties, the high-performance Agileflow concrete mix limited our labor requirements in constructing the walls where vibrating was not an option, which was a huge benefit in terms of time and cost savings,” said Hayden Mitchell, director of operations at Sizelove Construction. “In addition, there was no deconsolidation of the product in the heavily reinforced areas or honeycombing of the exposed concrete surfaces.”

 
agileflow structure2

“Due to its superb self- consolidating properties, the high-performance Agileflow concrete mix limited our labor requirements in constructing the walls where vibrating was not an option, which was a huge benefit in terms of time and cost savings” 

Hayden Mitchell
Director of Operations,
Sizelove Construction

 
 
Agileflow structural image