Scope of Services:

Installation of 4 cast in-situ CFA 600mm test piles across the three bridge sites in Kampala, testing of the four test piles to 200% of their working load, installation of the working piles across the three sites. The piles vary in length from 11 to 19m, all 600mm diameter. 

Location: Northern Bypass, Kampala, Uganda 

Completion Date: February 2017 

Main contractor: Mota-Engil Africa 

Client: Uganda National Roads Authority 

EAP mobilised a Soilmec CM50 to install the test piles. The test load was resisted by four reaction piles around each test pile, which were installed concurrently with the test piles. The concrete and steel cages were provided by the contractor. 

EAP mobilised a test rig comprising steel beams and ties and installed temporarily at each location. The load tests were to 200% standard working load in two cycles, one to working load and the second to 200% SWL. The working loads varied between 810kN and 840kN. The testing and piling works were carried out to Uganda ministry of works specifications. 

Displacement of the pile head was measured by displacement gauges attached to reference beams anchored well away from the pile under test. The pile head movement varied greatly from site to site. At Kyebando the consulting engineer revised the design of the working plies and increased the length following the load test result. 

Working piles were installed with the same machine and method. Great care had to be taken with piles for the pier in the central reservation since the work took place very close to the existing roadway. 

All piles were subject to integrity testing using the frequency response method. The data was taken using TDR2 machine and analysed jointly between EAP and ND Technology of Southampton, in UK, experts in the analysis of pile integrity test data.