CONTRACT VALUE: R139,612,430.00
START DATE: 20th JANUARY 2012
END DATE: 16th JULY 2013 (18 MONTHS)
KPMM MANAGEMENT TEAM
CONTRACTS DIRECTOR: MR. M. HICKMAN
SITE AGENT: MR. B. PRIGGE
ENGINEERS: AURECON AME
DESCRIPTION OF WORKS
The main objective of the employer was the rehabilitation and addressing of the sinkholes on Road P28-1 (N14) between Road R500 turn off to Carletonville, to the former Gauteng border (D1755).
KPMM’s objective during construction was to provide black empowered economic enterprise contractors a portion of the work as well as providing employment and work opportunities for the local community. To ensure this was adequately accomplished training was provided to the local labourers. This assisted in ensuring that all the work was completed with a high degree of safety, sensitivity to the environment and quality within the specified contract period of 18 months
Some of the road works included in this project consisted of the following.
- Capacity improvements of existing pipe culverts by raising and improving the gradient of the floor levels
- Repairing of the sinkholes and provide dolomitic grouting
- Extensive Concrete lined drains with waterproofed joints as shown in the two photos below.
At the commencement of construction it was found that the material next to the road was of inferior quality for the purpose of road construction. A new design was therefore required and this in turn resulted in the road final levels being lifted. All layer works material now had to be imported from a commercial source due to the lack of sufficient quality material along the construction site
Construction of the Cement Stabilized Sub base
The last material in the drum is placed evenly over the upper selected layer. Care must be taken not to leave a heap of base and a hole in the base layer.
In order to complete the final cut lane a 180 degree turn is required. The water tanker is therefore disconnected thus enabling the recycler to turn.
Milling assistance ensures no execs water is spilt on the un-compacted material which could cause a wet spot and “pumping” during the compaction process
At this point care must be taken to ensure that the correct nozzle are turned off so as not to spray a double application of water into the overlapped portions.
Not all of the very important compaction unit machines are illustrated in the above pictures. The complete process also consists of two pad foot rollers, smooth drum roller, grader and a pneumatic tyre roller. There are all required to finish the surface once the final levels have been achieved.
Constant monitoring is required to ensure a good quality product. Seen in this photo a sample of the mixed material has been collected between the rear wheels. Few of the test done on this sample will be a UCS and ITS. Once the layer is completed cement content and compaction tests will be done.