Deep Foundations

A look back and a look ahead

In the mid 1960's, when I became involved with the Deep Foundations Industry, things seemed to be simple. Chellis was our leader, the choice of pile foundations went from timber, H piles, pipe piles and precast concrete to various forms of mandrel driven piles including the Raymond Step Taper Pile.

Raymond Concrete Pile Company had offices spread throughout the United States. U.S. Steel and Bethlehem Steel were the major suppliers of steel piling and sheet piling.

Piles were driven with air and steam powered impact hammers, manufactured by Vulcan, McKiernan-Terry, Union Iron Works and others. There were diesel hammers by Delmag, McKiernan Terry and Linkbelt Speeder. Drop hammers were in use in many areas. Load bearing capacity was determined by some form of a dynamic formula and confirmed by static load test. Land pile rigs in use included lift cranes and skid rigs. In Chellis' book titled "Pile Foundations", the inside covers show primitive, early and medieval pile drivers. Some of these show remarkable resemblance to machines I have seen in use.

There were several types of caisson piles and caissons in the market. Some remain in use, methods and equipment have improved.

Today Raymond Concrete Pile is long gone, and have been followed by the piling products of the two major steel producers. It seems that the bureaucracy of large corporations eventually exists to serve themselves rather than to serve the marketplace.

Publicly held Corporations, in many cases, have a difficult time serving two masters. The first are the Stockholders whose concern is the next quarter’s earnings and when and if they should sell their stock. The second is the marketplace where their income is generated.

To keep the market satisfied one must stay ahead of the competition in service, quality, and innovation. This requires long term planning; an idea whose time may be over, at least as far as large publicly held manufacturing corporations are concerned.

Innovation in deep foundations in the United States seems to be driven from outside. The diesel hammers, hydraulic hammers, vibrators, and various drilling techniques come to us from Europe and Asia. Many of the innovators using modern technology are domestic companies using non-domestic technology or domestic contractors whose ownership is offshore.

Change in the Industry is happening slowly, but it is happening. A Contractor using old methods and machinery, long ago paid for, can compete with new technology because of the high cost of the new technology. This cannot last forever. Contractors are investing in new technology and the trend will continue. Many pile foundations in this country are installed by General Contractors that, because of a lack of local Specialty Contractors, do their own foundation work; or because of, their company policy is to do this work themselves.

Certain markets have a fair share of Specialty Contractors. These markets will probably be effected most by Contractors that use new, more efficient equipment and methods. It is difficult to see a bright future for Contractors who need a convoy of trucks and a day or more to set up equipment when their competitors can have their equipment unloaded from a single trailer and be ready to install piles in less than the time it will take for the competitors crew to stop for coffee.

Driven piles will be with us into the foreseeable future. These piles carry less risk than other types of piles. They are easily understood by all participants of the construction process. To some this translates to fewer problems.

Computers have entered the Industry to do everything from predict pile capacity to monitor every blow of the hammer. I hope someone is working on a method to control the weather on the jobsite.

Vibrators have been in use for many years and some projects have been done using this tool to drive bearing piles. Several years ago a Lock and Dam Project on the Red River founded on H piles used the vibro for installation. Other projects have also used vibros as a final installation tool.

The Deep Foundations Institute has done some ground work in this area, to try to come up with a method to predict pile load capacity when a vibrator is used. This seems to be a monumental task and some progress has been made (for more on this contact the DFI).

Noise and vibration are items that from time to time become important especially in residential areas and near sensitive structures. Piles such as the Omega Pile and the Fundex Pile certainly address these issues.

Piling itself may be changing. New materials such as Fiberglass Tubular Piles and recycled plastic piling will find a place, certainly in the marine market. I have seen a few types of recycled plastic piles, but none has seem to hit the mark and cost is very high. Fiberglass piles on the other hand show promise. They may have a bright future, but the producers are now going in their own direction with little input from the industry. I hope the window of opportunity doesn’t slam shut on their fingers.

In summary, change is inevitable. The question is how much and how fast? The new century will produce many innovations not obvious to us now. But first we have to get our computers to recognize the date Jan 01, 2000.