A massive concrete wall panel is being lifted from its horizontal position, where it was formed on a concrete slab, to a vertical orientation forming the perimeter of a new building. A large mobile crane applies the force while construction workers help orchestrate and control the fine-tuning of the panel as it moves through the air. This is the common scene to produce millions of square feet on construction projects around the world employing tilt-up concrete building envelopes, a process with more than six decades of history.
A team consisting of an owner, perhaps a developer, an architect, engineer and general contractor have worked hard to define a project with the optimum structural performance. This building is both resilient and highly energy efficient as well as making a striking and perhaps iconic statement of the owner’s goal with its aesthetics. The delivery of this program statement now turns to the talented team of craftspeople brought in with the expertise to achieve the final product. In an orchestrated fashion, the site is transformed into an array of activity across a broad horizontal landscape and seemingly little progresses until one day, a couple of weeks or more into the start, a building takes shape. Panels, massive and heavy with irregular geometry and patterns, have appeared from what was only the day before a flat site.
Unless you are present during the moments when these massive panels move into their designed positions, you might at first be concerned for the safety of those involved in erecting such concrete wall panels with large mobile cranes. While both reality and history note that tilt-up construction is an inherently safe method of construction, like all forms of construction, safety can always be greater. With this mindset, the Tilt-Up Concrete Association (TCA) has developed three new synergistic resources aimed at improving and communicating the safety of tilt-up construction. The revised TCA Safety Guideline for Tilt-Up Concrete Construction, the recently introduced TCA Company Certification Program, and the new TCA Erection and Rigging Training Program are now available to the industry. These resources and programs have been produced through the collaborative spirit of the industry’s leading contractors, committed to the continued improvement of both their own companies as well as the industry at large.
Safety Guideline for Tilt-Up Concrete Construction
A product of the TCA’s Safety Committee, led by Barclay Gebel of Concrete Strategies in St. Louis, Mo., the new safety guideline expands the concepts of safety programming, risk management and OSHA regulation implementation for tilt-up construction professionals.
“We were looking at documents developed during the middle of the last decade,” Gebel states. “We found that while much of the data was as effective and meaningful today as it was then, a whole lot more could be done to further stress the caution and preparation professional tilt-up contractors must have on their project sites. Our committee made the decision to overhaul the guidelines and strengthen the ability for them to be implemented effectively and routinely on project sites in any market.”
Gebel and the committee maintained the basic principles of the construction process to remain as true today as when it came into popularity during the mid-1950s. Since the floor slab is cast first as it is the primary casting surface for the wall panels, a solid dry work area is created for the building trades. In addition, constructing the primary building framework and structural elements on the ground eliminates the need for scaffolding, further increasing worker safety.
“Overall, tilt-up construction is recognized as a reliable and safe building method,” states Jim Baty, technical director for the TCA. “However, all construction methods require good planning, a solid safety program and regular review to make sure they represent the most effective means of protecting the workforce and the environment.”