Unimog

Dedicated equipment can always be developed with and for our customers for example for overwater, railway or difficult access projects.

Projects

Tilbury Pull Out Resistance Tests – Tilbury Docks

At the request of Keller Ground Engineering, Lankelma has just completed a phase ground investigation as part of the installation and testing of Lime Cement Columns at Tilbury Docks, SE England.

The works comprised of Cone Penetration Tests and Mostap sampling through previously installed Lime Cement Columns and Pull-Out Resistance Tests (PORTs).

CPTs were used to determine the engineering properties of the Lime cement Columns. Continuous 65mm diameter Mostap samples were obtained for subsequent laboratory testing by the Client.

Lime cement columns were installed as the ground improvement system for this particular site. At selected column locations, 500mm wide flat vane were installed at the base of the column and an attached pull-out cable run out to ground level. Following the column curing, one of Lankelma’s 20 tonne crawler units, with modified 20 tonne capacity hydraulic rams, was use to connect up to the cable and pull the flat vane to ground surface.
As with CPTs, the force required to pull the vane through the column back to ground surface was recorded and downloaded using a modified and calibrated pressure gauge, data logger and logging software. The results obtained were used to determine the undrained shear strength (and so working strength) of the individual Lime Cement Columns tested. The net pressure was determined by dividing the net force used to retract the vane by the vane’s cross-sectional area. A factor of 0.1 was then applied to derive the undrained shear strength profile for the column.

Airport Site Investigation

Over a possession of three night shifts, Lankelma CPT Ltd completed a site investigation for the construction of a new taxiway at an airport for Ritchies. Difficulties encountered included the location of some very important buried services and the time constraints placed on all workers because of security clearance and flight operations.

Thirty three tests to an average depth of ≈5.0m were completed on an area of soft grass adjacent to the aircraft dispersal and main runway that required minimum disturbance of the ground surface to control the dangers of FOD damage to air-side traffic. The all-wheel drive ‘Track-Truck’ performed impressively in the very wet conditions leaving behind only flattened grass.

M2 Motorway

Lankelma was asked by W.S.Atkins for Carillion Highways Maintenance to carry out an extensive test program on the M2 motorway in Kent. In 19, 6 hour night sessions, a total of 349 tests were carried out. Factual reporting was carried out on a daily basis. Using cone testing techniques ensured a cost and time effective investigation.

A combination of different special cones were used in the investigation. Cone and friction CPT’s were carried out to determine the material and grade of the chalk layers present. Our new Gamma Cone was used to detect variations in the natural radioactivity of the stratification. This helps to determine between the infilled clay and the highly weathered chalk. Finally we used the videocone for visual confirmation of the material.

Factual reporting was carried out on a daily basis allowing the investigation to be tailored to the site conditions. Using cone techniques ensured a cost and time effective investigation.