When submitting a permit application, use industry-developed tools and your manufacturer’s data to explain your plan.
The anchoring plan for your tent or structure is the one part of your permit submittal package that will change from job to job. The key to any plan is to present a professional, easy-to-read document for your permit official to follow and understand. The Tent Rental Division (TRD) of the Industrial Fabrics Association International (IFAI) has built tools for you to use just for this purpose. Here are a few pointers to help you develop a system to produce your own plan for each installation.
Know your engineering
The starting point for your anchoring plan will be the reaction load data from your tent manufacturer’s engineering documentation. This reaction data will show you all of the forces that must be resisted by your anchoring system under the analyzed wind pressures. Often, this information is available in generic form on a simple one-page reaction forces summary document or structural drawing from your tent manufacturer. This information is also commonly shown in product manuals and installation instructions. Pay close attention to the required safety factors because most tools and testing will only provide failure loads.
Use your tools
TRD has produced two engineering studies to put engineering and science behind how products are anchored and secured in the commercial tent industry.
The IFAI Staking Study, completed in 2006, was intended to provide tent renters with a valuable set of data they could use to estimate the holding power of traditional tent stakes. It addresses different staking variables such as stake diameter, stake embedment depth, stake inclination, stake fastening heights, group staking and different load angles. The study also provides tables of baseline holding capacities in different soils and shows ways for field personnel to correlate individual site conditions to the chart of listed loads. Information from the staking study is summarized in Pocket Guide: Pullout Capacity of Tent Stakes and IFAI Procedural Handbook for the Safe Installation and Maintenance of Tents and Fabric Structures.
The TRD Ballasting Tool, completed in 2012, was intended to provide tent renters with a viable method to address anchoring a tent without ground-penetrating devices. The study addresses multiple methods/configurations of use that will match up with the engineering data provided by your tent manufacturer. The results of this study were used to create variable formulas based on the design criteria of your tent system combined with the specific dimensional details of the ballast you intend to use. The output of the Ballasting Tool provides you the weight in ballast you need to resist the forces you enter into the input form.
TRD members may download the pocket guide and the handbook and access the ballasting tool at the “Resources” drop-down menu at the TRD website, www.ifai.com/tent.
Document your plan
Using the structural information provided by your tent manufacturer and one of the above tools, develop your anchoring plan. Provide the permitting official with clear information about your anchoring plan and the location of the anchors around the tent. Drawings, diagrams and dimensions are critical here. Most importantly, explain how you came up with your plan and tie it to one of the TRD studies.
Be prepared to back it up
In some situations, a permitting official may require you to perform a third-party test of your anchoring system plan. This may require a testing company to visit the jobsite with you prior to the event to mechanically pull on the anchoring system in the direction of resistance to document the results. Some tent rental companies own a device called a dynamometer, which they use to test anchoring loads on their own. In some situations, the permitting official may also want a structural engineer to review the results and plan for anchorage and to certify the plan with their stamp. Before a permitting official asks you for this backup, you’ll want to make sure you have your contacts established and know who you’ll need to call.
By Alex Kouzmanoff, CERP, vice president, Aztec Tents, Torrance, Calif.
Sidebar: Tent permit guide
What should be included in a tent permit application package? Tent manufacturer Aztec Tents, Torrance, Calif., has published a guide for tent rental companies. The document, Tent Permit Submittal Guide, covers topics such as site layout, flame certification, evacuation plans, statement of structural integrity and the anchoring plan.
The guide is available on the Aztec Tents website, www.aztectents.com, in the “Client Resource” tab in the “Documents” section. Printed copies are available from Aztec regional account managers.