Technical Papers

The staff at Olson Engineering has created – and contributed to – numerous technical papers throughout the company's history. The publications featured on this page are available for download or review and are grouped by their common applications.


North Carolina Dam Tomography

This paper discusses how Sonic Pulse Velocity (SPV) analysis was used to assess the condition of a concrete arch dam in western North Carolina.

NDT of Dams and Other Structures

An overview of several stress-wave based nondestructive testing methods which can be used to assess the condition of concrete structures such as dams, buildings, and foundations.

Assessment of Concrete Dams

There are a number of nondestructive evaluation (NDE) methods applicable to the condition assessment of concrete dam structures. This paper includes a discussion of the methods and their applicability to different types of dams and structures related to dams.


IES Method on Post Tension Duct Voids

This paper focuses on imaging and scanning technology based on the rolling Impact Echo (IE) method. The basic background of the Impact Echo technique and its implementation with a rolling scanning transducer are discussed.


Epoxy injection and a concrete patching material were used to repair cracks in the damaged girder; after repairs were complete, a nondestructive testing program was developed to assure the quality of the repairs.

Unknown Bridge Foundations

A summarization of research work undertaken to evaluate the capabilities of the various nondestructive testing methods to indicate depth and other information on unknown bridge foundation characteristics.

Bridge Load and Stay Cable Testing

This paper discusses bridge displacement monitoring using a remote, noncontacting interferometric phase radar system (IBIS-S) and its results compared to a conventional bridge load test using string potentiometers.


Drilled Shaft Investigation

The Crosshole Sonic Logging (CSL), Crosshole Tomography (CT) and Sonic Echo/Impulse Response (SE/IR) methods are discussed along with case studies to illustrate the use of each method to determine shaft integrity.

CSL Tomography of Drilled Shafts

This paper presents a review of the Crosshole Sonic Logging (CSL) method in consulting and research projects and discusses the use of Crosshole Tomographic (CT) velocity imaging of concrete defects in shafts.


NDE of Concrete Pipe (PCCP)

This paper presents research and field work performed on Precast Concrete Cylinder Pipe (PCCP) using NDE methods to determine outer grout layer integrity and concrete bonding to an embedded steel cylinder.


IE Method on the Lincoln Memorial

The IE method was used on the Lincoln Memorial for two different projects: the first was a condition survey of concrete portions of the memorial under the Raised Terrace and Approachway Slabs; the second was a preliminary stone survey.