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  • We are the UKAS Accredited PTSI & NDT Experts

Post Tensioned Investigations

3 Steps to Preventing total Bridge Collapse

The HTA 3 Step process has transformed the Post-Tensioned Special Inspection process, utilising GPR and Tomography we reduce structural damage while locating tendons, their profile and subsequent detection of any hidden defects.

HTA have over 30 years of bridge investigation experience offering a Multi Disciplined & Multi Skilled Approach removing the necessity of having multiple companies on site and the required management of various operations.

Step 1: Location of Voids via GPR

This approach reduces damage from traditional stitch drilling

HTA reduces damage, time on site, and guesswork by taking advantage of GPR technology.

The following video highlights how Ground Penetrating Radar confirms the tendon location and their profile, reducing asset damage, time on site, and guesswork by taking advantage of GPR technology.

Step 2: Detecting Hidden Defects via Ultrasonics

Using Tomography via Proceq's Pundit Live Array

Watch the following video to see the Pundit Live Array being used to detect hidden defects as our Engineer runs this unit along the predetermined tendon profile.

Step 3: Targeted Localised Opening Up

Confirming the digital data with accurate breakout

Confirmation of a potential void location from step 2. Localised drilling is undertaken to expose the post tensioned system for the purposes of inspection to ascertain it's condition.

Localised breakout - Henderson Thomas Associates

The Result:

Below we have highlighted confirmation of the digital data along with localised breakouts. At two separate locations we exposed the tendon to confirm a well grouted tendon within it's sheath and hidden voidage at another location and their associated scans.

GPR & Ultrasonic Tomography result from Henderson Thomas Associates

Take advantage of our Open Door Policy

Even if you do not end up using HTA we are happy to advise on the best course of action for the outcome you wish to achieve.

It is impossible for one company to carry out every project, however we can share our expertise far and wide.

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