On May 7, 2003, 3-D Concrete Correction Company installed 14 new construction anchors for Total Industries, Inc. Mr. Jack Long, CEO of Total Industries purchased from Giddons-Lewis LLC a State-of-the-art horizontal boring machine that is capable of cutting molds 20' x 15' horizontally within 4/1000 of an inch. However, the designed engineered foundation for the machine required an intricate concrete base 10' deep x 24' wide x 22' long with a web of reinforcing steel throughout. The problem for the business owner was four-fold; each posing a major hurdle to over-come:
- Depth. The machine was to be stationed in the pre-existing shop which was only 40' wide - the sub-grade consisted of sand, and with the existing structure's load bearing walls only 10' from 2 of the outside edges of the proposed machine site, and these load bearing walls resting on spread footings 4' deep, the required escavation needed to create a 10' deep pit would most definitely undermine the existing structure's foundation, based on the natural slope calculations of sand.
- Load Capacities. The machine was a dead load requirement of 80 kip, and also has a live load capacity of up to 50 kip, giving a working load requirement of 130 kip. Also, the machine operates on a horizontal plane which shifts horizontal loads laterally. This requires a stout anchoring system to secure the machine to the base pad for uplift constraints. Therefore, any reduction of depth to the original foundation plan would compromise compression load capacities as well as reduce uplift constraint capabilities.
- Time. The machine had been purchased and was scheduled to be delivered within 4 weeks. Had the original foundation plan been followed, sheet piling would have had to be driven, escavation accomplished, a massive reinforcing steel grid accomplished, a complex drain system and sump pit area formed, concrete poured (approx. 120 yrds), and curing time allotted. This task would have been impossible to achieve within the time frame given.
- Cost. The estimated cost of the original designed foundation reached over $40,000. We believe these estimated costs were low, based on hidden factors not known to the estimating concrete contractor who submitted a proposal.
3-D Concrete Correction Company escavated the foundation footprint to depths that would achieve a 17" concrete base pad. We then installed 14 A.B.Chance helical anchors, ss-5 triple lead sections and extensions to an average of 20' per anchor. No stabilization of the existing structure was required based on the same natural slope equations used for the originally proposed 10' deep base. The A.B.Chance helical anchors were installed to 50 kip load capacities each. Then, an engineered reinforcing steel configuration was installed encapsulating our anchors to give them uniformity. The concrete base pad (17" x 24' x 22') and reinforcing configuration was engineered by Keller Engineering, South Bend, IN, and installed by 3-DCCC. The successful outcome of this project answered all four original hurdles:
- The excavation depth required was a total of 24" eliminating the concern of undermining the existing structure's foundation.
- The load capacity given by the A.B.Chance helical anchors for compression and uplift of the machine was more than sufficient. Each anchor registered 50 kip times 14 anchors = 700,000 lbs total compression capacity.
- The time the project took from start to finish was 2 weeks. - well within the time frame given. It is 3-D's opinion that if the original foundation plan had to have been followed, it would have been impossible to complete that task within the four week time frame.
- The total cost of the project was $26,500.00. This was well within the budget of the owner who would have had a cost of $40,000 - $50,000 for the construction of the original foundation plan.
The A.B.Chance Helical Anchoring System and 3-DCCC again demonstrate the wide range of time and money-saving solutions we offer for deep foundation requirements in a variety of applications.