Other Nondestructive Test Methods

other nondestuctive testing methods

Testing to see if it vibrates, resonates or dissipates

CTLGroup has experience with other nondestructive testing methods.

Vibration Monitoring

As a nondestructive testing company, CTLGroup uses state-of-the-art technology to measure and monitor vibrations in structures and construction sites. Electronic sensors capture and store recorded vibrations above a preset trigger level. Recorded data are then plotted against a curve representing the U.S. Bureau of Mines criteria for building damage. The systems can be configured to alert personnel automatically when established threshold values are exceeded. Our experts can design, supply, install, and implement monitoring systems to serve a wide range of purposes.

Baseline Vibration Measurement

Baseline ground vibration measurements can serve as a base for comparison to subsequent construction and operation vibration levels.

Continuous Vibration Monitoring

CTLGroup can supply systems to monitor vibrations continuously during the course of a project and record changes in vibration levels over time. 

Laser Vibration Monitoring

CTLGroup uses a non-contact laser vibrometer to measure low-level vibration in structural cables on bridges.  In this procedure, a laser beam is aimed at each cable in order to acquire vibration data. Ambient excitation sources, including wind and traffic, usually induce sufficient vibration in cables. The laser can target the cables from distances of hundreds of feet, thus reducing the need for laser repositioning and time required for force measurement.  The laser technique provides a rapid and cost-effective alternative to other force measurement techniques for stay cables, such as the lift-off method.

Who and Why?

Both owners and contractors have hired CTLGroup as a nondestructive inspection company to monitor vibration on their construction sites and ensure that levels are low enough not to damage adjacent properties. Historic buildings can be particularly vulnerable, so vibration limits for nearby construction activity may be limited more strictly in historic districts.

Ultrasonic Flaw Detection (UT)

Ultrasonic Testing (UT) uses high frequency sound energy to conduct examinations and make measurements. Ultrasonic inspection can be used for flaw detection/evaluation, dimensional measurements, material characterization, and more.

Benefits of UT

  • It is sensitive to both surface and subsurface discontinuities.
  • The depth of penetration for flaw detection or measurement is superior to other NDT methods.
  • Only single-sided access is needed when the pulse-echo technique is used.
  • It is highly accurate in determining reflector position and estimating size and shape.
  • Minimal part preparation is required.
  • Electronic equipment provides instantaneous results.
  • Detailed images can be produced with automated systems.
  • It has other uses, such as thickness measurement, in addition to flaw detection.

Infrared Thermography

Infrared techniques can be used to detect flaws in materials or structures. The inspection technique monitors the flow of heat from the surface of a solid and this flow is affected by internal flaws such as disbonds, voids or inclusions. Sound material will see heat dissipate rapidly whereas a defect will retain the heat for longer.