Ram Jack Helical Pile Q & A: Part 2
Your questions posted during our live engineering webinar, “Helical Design: Code Compliance and Effects of Seismic Activity,” answered.
If you weren’t able to attend or participate in the accredited webinar, you can register for the recorded online session to earn your PDHs or contact your local Ram Jack for a free Lunch & Learn with the accredited webinar. You can also read Part 1 of the series.
Does Ram Jack execute the installation of your products or just sell the parts?
Ram Jack manufactures and installs the piles so we can have more quality control in the process. All the installers are certified by Ram Jack, and the product is sold to and can be installed only by an authorized Ram Jack franchise. Consequently, we are able to provide a lifetime warranty for residential applications and warranty our products for its specific design life in commercial applications.
Is there LRFD design methodology for helical piles?
As with all foundations systems, helical piles can be designed by both LRFD and ASD methods. The respective load factors would be applied and the piles designed accordingly.
When designing using LRFD methods what phi factor should be applied to Q ultimate?
Section 188.8.131.52 – LRFD Method of AC358, “When using the LRFD or strength design method, and ASD provisions are not contained in the code-referenced standards, such as ACI 318, the allowable design capacity, P’, shall be taken as 0.7 times the design strength, ØPn, where ØPn is determined in accordance with the applicable code or reference standard. P = 0.7ØPn (LRFD)
Please discuss performance of helical piles for support of vibrating equipment such as generators and other rotating machinery.
Most helical manufacturers use through-bolted connections which can have as much as 1/8” of slop per connection and therefore can cause vibrations when you have reverse or dynamic load conditions. Ram Jack is the only helical manufacturer with a unique internal threaded connection. As the piles are torqued into the soil, the friction developed between the two faces of the connection weld themselves together. This makes for an extremely rigid connection with no eccentricity or slop.
Any thoughts for applications in areas with sink holes?
Ram Jack does a lot of work in Florida and Tennessee where sink holes are active. Typically, we use our system to underpin the structure and perform a controlled lift of the foundation. Once the piles have been installed, deep grouting is performed as normal. However, less grout is typically needed when performed in combination with the underpinning. Here is a link to a case study of a Fire Station in Williston, FL where this method was used. 420 cubic yards of grout was estimated in the original proposal. Ram Jack underpinned and raised the structure. Afterwards, only 40 cubic yards of grout was required.
Do you have contact information (address and phone number) for a Ram Jack provider in my area?
With over 60 locations across North, Central, and South America, we’ve got you covered. You can find your local Ram Jack on our site.