Channel size and style, fittings, elevations, spacings, and overall dimensions are important aspects of a Unistrut support structure design, but of equal or greater importance is how the system attaches to the concrete ceiling. Our recent work with a general contractor troubled by the presence of hollow core concrete panels is a case in point.
Hilti HDI-P Concrete Anchor
The low-cost, hollow core concrete ceiling sections commonly used in office building construction can create significant design challenges in hospital settings. In this case, our GC had concerns over securing 1,000 pounds of x-ray equipment to a hollow core panel style ceiling with traditional concrete anchors, per his supplied drawings.
One suggested option-reinforcing each hollow section panel with liquid grout-wasn’t feasible because the process would have taken 2-3 weeks and put the GC behind schedule and over budget. We don’t come across hollow core concrete panels in hospital settings often, but when we do, we recommend Hilti HDI-P drop-in anchors. The Hilti-HDI-P is an internally threaded, flush mounted expansion anchor designed for solid and core panels, precast plank, and
HDI-P Loads–Normal-Weight Concrete and Hollow Core Concrete Panels
Click to Enlarge Table
To eliminate any potential concerns over safety, each of the 12 anchors connecting the support structure to the concrete ceiling was pull-tested at 500 lbs:
The test results confirmed a secure connection at each anchor point, ensuring the safety of the x-ray equipment, as well as the lab technicians and patients. Our knowledge of concrete, medical support systems, and available anchoring products saved the general contractor boatloads of money—and time.
We don’t typically dedicate an entire post to a discussion of concrete anchors, but this installation offers some key takeaways that may serve you well in the future. For starters, this install ended well, but critical decisions made early in the design process could have led to a very different outcome. The GC (a repeat customer) brought us in
We have years of field experience, and the challenges we overcome during installations inform our design choices on a daily basis. Each overhead support structure—and each room—presents a unique combination of obstacles standing in the way of a successful installation, but GC’s, structural engineers, and architects rely on us because we have the technical expertise, materials, and installers needed to get the job done on time and on budget.
Do you have an upcoming project requiring the design and installation of a ceiling mounted