CROSS Safety Report
Failure of pile load test arrangement
This report is over 2 years old
Overview
A pile was being load-tested, for confirmation of design pile loads for the foundations of a road bridge, when the web of the deep steel beam used in the testing arrangement buckled.
Key Learning Outcomes
For construction professionals:
-
It is good practice to have a load test arrangement designed and assessed by a suitably qualified engineer to ensure the members can accommodate the test load
Full Report
Find out more about the Full Report
The Full Report below has been submitted to CROSS and describes the reporter’s experience. The text has been edited for clarity and to ensure anonymity and confidentiality by removing any identifiable details. If you would like to know more about our secure reporting process or submit a report yourself, please visit the reporting to CROSS-UK page.
In 1985, a 12m long 600mm diameter pile was being load-tested for confirmation of design pile loads for the foundations of a road bridge. The testing arrangement was a deep steel beam with a tension pile at each end and a load cell in the centre pushing against the pile (Figure 1). At around 1.5 x working load (105t), the beam web buckled, and the load dropped back to an approximate working load of 76t.
The pile contractor unloaded the pile, welded some stiffeners in and reloaded satisfactorily to 1.5 x working load for 48 hours. Analysis of the beam to BS449, showed the web as being close to buckling at 105t, with fbc=179N/mm2 and fe (fbc+fb+fq) =194N/mm2 at midspan, cf 230N/mm2 max.
The pile contractor had just taken over the sub-contract from the previous contractor, who had gone into administration. Hopefully this failure would not be dealt with in this manner these days!
Submit a report
Your report will make a difference. It will help to create positive change and improve safety.
Our secure and confidential safety reporting system gives professionals the opportunity to share their experiences to help others.
Feedback
No feedback has yet been published for this page.
Expert Panel Comments
Expert Panels comment on the reports we receive. They use their experience to help you understand what can be learned from the reports. If you would like to know more, please visit the CROSS-UK Expert Panels page.
There are no Expert Panel comments on this report. The Expert Panels are only asked to comment on selected reports. These are normally reports where there is an opportunity for them to help you understand what can be learned from the report.