School Pumping Project Earns High Grades
School Pumping Project Earns High GradesPutzmeister pumps place 4,885 cubic yards of concrete for schools
STURTEVANT, WI (February 16, 2009) – As part of Orange County Public School’s initiative to renovate existing schools and build new schools in their jurisdiction, T&T Construction of Central Florida (T&T), and their Putzmeister concrete pumps, are placing concrete for both Dommerich Elementary School (Dommerich ES) and Maitland Middle School (Maitland MS) in Maitland, Florida.
In September 2002, a half-cent sales tax in Orange County was approved. This tax is funding the Dommerich ES and Maitland MS projects, as well as the renovation and replacement of other existing schools in the county.
A new two-story school is being built to replace the old Dommerich ES. Once the new school is complete, the old one will be demolished, according to Stuart Henry, vice president of operations for Welbro Building Corporation (Welbro).
At Maitland MS, a new two-story classroom building is being built, while four original buildings on campus (the Media Center, Music/Art building, a locker room and gymnasium) will remain unchanged. The rest of the buildings will be demolished. The Maitland MS project will also include technology upgrades as well as fire sprinkler and security additions.
“Both schools are being constructed at the same time, during the school year and on a restrictive footprint, all of which bring their own challenges to the table,” says Henry. “Given these multiple challenges, we needed to choose our sub-contractors carefully and ensure clear communication from the top, down.”
Breaking ground in July 2008, Welbro chose Casselberry, Florida-based subcontractor T&T to manage the concrete pumping and masonry needs.
“We’ve worked with T&T and their innovative equipment before so we are confident they will get the job done on time and on budget,” says Henry. “We also know they hold their safety standards very high. That’s always number one priority on our job sites, so it’s important to us that we work with sub-contractors who have the same values. In fact Welbro, along with the project’s Site Safety Committee, have recognized Gilles Belanger and Gabriel Chimal of T&T for their outstanding dedication to the job site rules and General Site Safety compliance on this project.”
Tarmac of Port Orange, Florida, was hired as the concrete ready mix supplier.
Accessibility Working Against Them
“Because the new school buildings are going up right next to the old ones, our accessibility automatically became much more restrictive in terms of getting our machines around on site, while placing the concrete and grout in an efficient manner,” says Philip Keys, manager of the concrete pump department of T&T. “The restrictive site made us select our equipment differently; knowing which units are the most maneuverable, while also providing a quick setup and teardown was key.”
The Putzmeister equipment that T&T has on site for both schools includes a 58- and 40Z-Meter truck-mounted concrete boom pump, along with their Thom-Katt® TK 70 and TK 40 pumps, and a P30 mechanical grout and concrete pump.
“Both of our boom pumps on site have proven to be invaluable,” notes Keys. “Our 40Z-Meter offers a compact and lightweight design, making moving from location to location seamless. For this project, we’re moving multiple times throughout a pour, and the teardown and setup process takes a mere 15 minutes.
“In addition, our 58-Meter, although larger, is still very versatile on site as well, offering an impressive 260 cubic yards per hour (200m3/hr) output.”
“Both of our Thom-Katt trailer-pumps are compact, easy to operate, reliable and inexpensive to maintain,” comments Keys. “They provide fast setup, smooth pumping, easy cleanup and long-term dependability, all of which make having the trailer pumps on site a tremendous advantage for all involved.”
Multiple Pumps, Multiple Mixes
The boom pumps are on site to pump and place concrete for slabs, panels, elevated decks and some footings. The trailer pumps are on site for the pumping and placing of concrete for columns, tie beams, cell fills (masonry block) and pan stairs. A P30 is available to fill in if the Thom-Katts are unavailable for a day’s pour.
A total of 4,885 cubic yards (3,735m3) of concrete will be pumped and placed. Combined, the boom pumps have pumped a total of 4,385 cubic yards (3,353m3) of concrete and the trailer pumps have pumped about 500 cubic yards (382m3) of concrete.
“Because this project was done during the school year and in a residential area, we were required to pump during non-school hours, so our pours always occurred during the night,” says Jay Swank, a boom pump operator for T&T. “Many benefits came from this, including less traffic to navigate through and fewer safety concerns because we weren’t pumping when the students were on campus.”
“Most of our pours averaged from one to three pours per week,” adds Keys.
On September 11, 2008, the first pour for the foundation and slab-on-grade occurred for Maitland MS. Within 5 hours, 450 cubic yards (344m3) of concrete was pumped and placed.
The first pour for Dommerich ES occurred on September 30, 2008 which was also for a foundation and slab-on-grade. 600 cubic yards (459m3) of concrete was pumped and placed in about six hours.
“Throughout the project our 58-Meter has showcased its versatile four-section roll-and-fold boom,” notes Charles Sparks, a boom pump operator for T&T. “The boom design features an impressive 188' 1" (57.33m) vertical reach and a 174' 3" (53.11m). Anywhere we needed to place the concrete for either school the boom pump had it covered, no problem.”
“Our 40Z-Meter was primarily used for the tilt-up panels and elevated decks on both schools,” comments Keys. “It can pump up to 210 cubic yards of concrete per hour (160m3/hr) at 1,233 psi (85 bar). An additional feature that has not only been helpful to have on this job site but others as well, is the four-section Multi-Z boom design which has up to a 128' 3" (39.09m) of vertical reach and 115' 2" (35.10m) of horizontal reach.”
According to Keys, both boom pumps have been averaging an output of about 100 cubic yards per hour (76m3). The trailer pumps have also proved to be workhorses on the job.
“Our Thom-Katts feature impressive output at high pressures,” notes George Swiger, TK operator for T&T. “The TK 40 can pump up to 40 cubic yards per hour (30m3/hr) at a maximum high pressure of 1,150 psi (79 bar), and our TK 70 can pump up to 74 cubic yards per hour (57m3/hr) at a maximum high pressure of 1,130 psi (78 bar).”
According to Phil Crawford, concrete project manager for T&T, their TKs will be on site yet for a few miscellaneous pours as the project wraps up.
Crawford also notes that multiple concrete mixes and strengths are being used on both schools.
“We have a regular 3,000- and 4,000-psi concrete mix,” says Crawford. “The 3,000-psi mix is being used for slab-on-grades and foundations while the 4,000-psi mix is being used for vertical walls and tilt-up panels.
“In addition, we have a 4,000-psi pump mix. The pump mix has a smaller aggregate mixed in. This mix was used for cast-in place tie beams, stairs and vertical columns on both schools.”
According to Crawford, they are also using a 3,500-psi blended mix which is a combination of large and small aggregate. The mix was used for the elevated slabs for both schools.
“We also have a 7,000-psi grout mix that was used for the tilt up panels. The grout was pumped by our trailer pumps,” adds Crawford. “This grout mix was placed under the tilt panels to give it more support; basically, the grout bound the panels and the floor together.”
All of the concrete mixes except for the 7,000-psi grout mix was placed with the two boom pumps.
Keeping it Moving
T&T has most of the concrete pumping and placement completed except for a few miscellaneous pours where the TKs will be needed through June 2009. Both schools will be ready for use in August 2009.
In the 14 years since it originated, T&T has grown into one of the largest concrete and masonry companies in Central Florida, and they don't show any signs of slowing down. A few projects the company is currently working on include Premeire Beverages’ 550,000 square-foot warehouse in Tampa, Florida; Osceola County Middle School in Kissimmee, Florida and a Target store in West Melbourne, Florida.