Articles
Building Investigations Services - Infrastruct
January 8, 2020

Building Investigations

Late in 2019 Infrastruct was instructed by our Client to carry out testing and investigations on an old multi-storey building which was showing evidence of significant distress and deterioration. The goal of the structural testing and material investigation works was to conclusively determine the cause of the distress and deterioration.

The testing and investigation works included:

1. Reinforcement cover and layout surveys
2. Half-Cell Potential surveys
3. Carbonation depth measurements
4.Concrete dust sampling for chloride content analysis (laboratory testing)
5.Ultrasonic Pulse Velocity (UPV) testing on concrete beams and columns
6. Coring for:
a) Compressive strength and estimation of the characteristic compressive strength of the concrete
b) Petrographic examination of the concrete.

Photographs 1 and 2 below show the testing on the columns to determine the cover to the reinforcement and the UPV results for in-situ concrete quality assessment.

The results of the testing were recorded on-site by our staff and a comprehensive report, with interpretation, was prepared for our Client. The cause of the deterioration in the concrete was determined by the testing programme.

For more information on structural testing and investigations on buildings or other structures, please contact Dr Thomas Callanan in Infrastruct Asset Management Services Limited.

Articles
Non-Destructive Testing on Railway Track Slabs
April 21, 2018

Non-Destructive Testing on Railway Track Slabs

Infrastruct was part of an engineering team that carried out a range of structural testing and investigations on reinforced concrete track slabs in a tunnel in Scotland.

Infrastruct used combination of non-destructive testing systems on this project to investigate the integrity of two separate sections of track slab.

The non-destructive testing systems used by Infrastruct to locate and target weaker areas or to locate areas with structural changes in the track slab were as follows:

  1. s’MASH Impulse Response to survey on the top surface of the concrete track slab. This testing was completed in a grid pattern on the top surface of the track slab to rapidly identify suspect areas for further investigations using other testing systems. In total, there were 328 s’MASH test points recorded and analysed.
  2. MIRA Pulse Echo Tomography on the top surface of the concrete track slab to graphically examine the concrete integrity in the suspect areas of the track slab.  Selected areas on the slab were scanned using the MIRA pulse echo system to determine if major voids or anomalies were present within or beneath the track slab.
  3. Impact Echo (Olsen CTG-2D) to survey the selected locations and map the changes in the slab thickness.
  4. Ground Penetrating Radar (GPR) to survey the slab using a 1GHz antenna on the top surface and locate embedded reinforcement and other services.

The combination of s’MASH Impulse Response, MIRA Pulse Echo Tomography, CTG-2D Impact Echo and GPR proved successful on this project in determining the defects under the track slab.

The results of the non-destructive testing were recorded on-site by our Engineers and a comprehensive report, with interpretation was prepared for our Client.

For more information on non-destructive testing on structures, please contact Dr Thomas Callanan in Infrastruct Asset Management Services Limited.

Articles
Post-Tensioning Special Inspection on 3 Span Bridge
June 17, 2016

Post-Tensioning Special Inspection on 3 Span Bridge

Infrastruct AMS with a well-known civil engineering contractor recently completed a Phase 3 Post-Tensioned Special Inspection (PTSI) on a large three span bridge in the West of Ireland.

Combining the techniques of Ground Penetrating Radar (GPR), Impact Echo and Linear Polarisation Resistance (LPR) we were able to plot the post-tensioning duct profiles in each beam, non-destructively assess if voiding was present in the ducts and measure the rate of corrosion on the embedded reinforcing bars.

Duct and tendon exposures at selected locations confirmed the Impact Echo test results showing fully grouted sections as well as partially or fully voided sections in the ducts.

The pictures below show the marked-up duct profiles on the beams, the Impact Echo testing and a duct and tendon exposure in a fully voided section of post-tensioning duct.

For more information on any of the specialist testing described above or indeed any structural testing and investigations please contact Dr Thomas Callanan in Infrastruct Asset Management Services Limited.

Articles
July 9, 2015

Special Inspection of Reinforced Concrete Tanks

Special Inspection of Reinforced Concrete Tanks
In late 2014, Infrastruct AMS Limited carried out Special Inspections on 3 no. reinforced concrete tanks in a large wastewater treatment facility in Co Dublin. The tanks were out of service for several months and a brief inspection revealed chemical deterioration present on the internal surfaces. Confined spaces trained teams from Infrastruct AMS Limited completed the following works:

1. Hi-pressure water jetting of all structural elements to enable a detailed visual inspection of the internal surfaces;
2. Ground Penetrating Radar (GPR) survey to examine the integrity of the concrete and confirm the location and layout of the embedded reinforcement;
3. Corrosion assessment to confirm corrosion activity and determine the rate of corrosion in the concrete;
4. Crack mapping and measurement, including the depth of cracking on the internal surfaces;
5. Concrete sampling and laboratory testing to determine the properties of the concrete and conclusively establish the source of deterioration in the concrete. All Special Inspection work was under the supervision of our in-house Chartered Engineer.

A detailed technical report was prepared for the Client with recommendations on the most appropriate repair strategy for the three structures.

Articles
Concrete Testing on Reinforced Concrete Structure - Infrastruct
July 9, 2015

Concrete Testing on Reinforced Concrete Berthing Structure

Concrete Testing on Reinforced Concrete Structure - Infrastruct
During the spring of 2015, an engineering team from Infrastruct AMS Limited working with a large contracting firm carried out concrete testing and material investigations on a reinforced concrete deepwater structure to determine the following:

1. Location and layout of reinforcement in the structural beams supporting the deck slab;
2. The reinforcement properties to enable a comprehensive structural assessment to be carried out;
3. The condition of the embedded reinforcement to assess the severity of corrosion;
4. Compressive strength of the concrete by removing cores from the structure;
5. Determine the ingress of aggressive chloride ions in the concrete.
6. The results of the testing and investigation works were compiled and a detailed report issued on the findings.

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