The aim of the Cross-Hole ultrasonic analysis is to estimate the actual depth of the foundation stuctures, as well as their integrity, the material homogeneity due to the absence of construction defects, such as crawl spaces, runoff, restrictions, and the intrusion of any raw material.
The analysis’ technique relies on the study about the mechanical vibration’s pulses propagation along a serie of trajectories within the structure to be examined (usually three of them).
Such methodology relies on the principle that in the concrete with good mechanical features, intact, homogeneous and compact, there are well defined and high value (3500-4500 m/s) propagation speeds of vibration pulses.
Emission and reception of the vibration pulses take place through two probes, one emitter and one recipient, moving on the operator’s command within the structures in question, by using appropriate diameter tubes, meant for this specific goal and then, embedded in the concrete during the jet process.
The probes move within distinct and parallel holes, remaining on the same horizontal line joining, or on an appropriate lag. The inquired material is that one included between the emitter probe and the recipient one.
The issuing probe, moving into the structure, delivers constantly (with an appropriate adjustable frequency) vibration pulses that, once picked up by the recipient probe, are introduced into a special processing unit. The latter prints, according to the the pulse’s inspection depth into the structure.
The graphic and numerical analysis of the US pulse’s speed is made by processing, through PC or dedicated software, the data recorded during the test; the result consists in a diagraphy allowing the immediate detection of possible defects on the pole’s stem.
- Establishing the foundation pole’s length
- Identification of discontinuity, gaps, break-lines and sbulbatures.
- Identification of the flaw’s location through tomographic techniques by making a greater number of analysis along the different sonic routes.
- Non-invasive technique
- Establishing immediately the test values
- Check on poles of large diameter