Frequently Asked Questions

What is the purpose of failing a test pile?

A test pile will be considered to have failed when the failure criteria given in Section 804.11 has been achieved. After meeting these criteria, the ultimate strength of the soil down to the test pile tip elevation may be used to help develop production pile lengths for a bridge site.

What is needed for pavement design/review?

    • Subgrade Soil Survey
    • Cores of Existing Roadway
    • Traffic Data Provided By Data Collection and Analysis Section (Thirteen different vehicle type classifications as specified by 1993 AASHTO Guide for Design of Pavement Structures)
    • Preliminary Typical Sections if Available

What is the Pile Driving AnalyzerTM (PDA)?

The Pile Driving Analyzer TM is a computerized data acquisition system that records the Force and Velocity waves in the pile during a hammer blow. These measurements are obtained by attaching two strain gauges and two accelerometers below the top of the pile. This system is used to measure the pile driving hammer performance, pile driving stresses, pile capacity, and soil parameters during the installation of the pile. The field data is evaluated to develop efficient pile driving criteria for field personnel.








How does boring elevations affect the construction and/or Design of a structure?

Without proper elevations the following can occur:

    • Pile cutoff
    • Pile failure
    • Over designed piles
    • Stability issues
    • Ineffective embankment settlement estimations

 How do I determine the pile bearing capacity in the field?

The pile bearing capacity is the pile capacity obtained during the end-of-driving or pile restrike. The pile bearing capacity determination shall be made by use of either the Dynamic Formula or the Wave Equation as specified in the plans.

 Is there a Geotechnical Design Manual?

Not yet; however, we are working on it.  We are currently working on getting the first few chapters finalized in the near future.