1. Scope of Works This method statement describes the operations required to manufacture and produce dense bitumen macadam binder course and asphalt concrete wearing course. Both product are hot mixes produced in an asphalt plant specifically designed for the purpose. 2. Reference Documents General Specifications for Road and Bridge Works Republic of Uganda Volume 3A Section 4500 Special Conditions of Contract Tender Dossier Volume 4 Section 4500 3. Materials Approved aggregate produced at the on site crusher. (subject to separate MST) Penetration Grade Bitumen 60/70: specification BS 3690 4. Plant and Equipment
Refer to Annex A.
Asphalt Mixing Plant. The plant will be capable of producing DBM and AC at the required tempo and quality to suit the contract specifications and programme Asphalt Plant SBM 200 Comprising the following components 4 Compartment Cold Feed Unit each compartment 11m3 Collecting conveyor under cold feed bins Ermont/Fayat Drying drum 7500mm long x 2100mm diameter Weinshaupt Monarch Type Wk 4 Burner An Ankerloken bag filter dust collection unit with 13 m high chimney, captured fines are feedback to the mixer Endress Hauser Bitumen pump and system Astec Incline conveyor and Storage Bin
Rincheval/Fayat Heated Bitumen storage tanks Control cabin with an appropriate computer 500 Kva Volvo driven 400Volt/50 Hz Electric Generator Workshop Container Spares and store container Front End Loader Mass measuring devise (Weighbridge)
5. Supervision and Labour Plant Supervisor Plant Operators Labour 6. Production of Asphalt Calibration of plant. Scales, pumps, meters. Once the approved laboratory mix designs have been received trial mixes will be produced in the plant and tested, to check the comparison to the laboratory mix designs. Trial mixes will then be produced and paved. Once approval is received production of DBM will commence. The calibration of the mixing plant is regularly checked on an ongoing basis when in production. When the plant is in full production, the operational sequence will be.
A dedicated bitumen team supervises the bitumen storage yard and ensures that the product is properly handled and delivered to the tanks at the plant at the correct temperature. The plant supervisor checks that the start up procedure is correctly followed at the plant. Mixing of either DBM or AC is then started and product is stored in the surge bin. Transport vehicles load from the surge bin weighbridge and proceed to the paver on the road. Production continues throughout the day. Quality control as well as process control testing is carried out according to requirements. Close liaison between the mixing plant and the paving team is by radio. All Asphalt operations, quality, productions fall under the Asphalt Manager.
6. Hazards and Risks Risk assessments Refer to: - Health and Safety Plan 110.199/PRM/QSE/HSP/001 - BASIL READ Hazard Identification and Risk Assessment Forms
On going risk assessments and training of personnel is seen as paramount importance to site management with the view to maintain a high priority on safety risks issues. Environmental risks Refer to: - Environmental Management Plan: 110.199/PRM/QSE/EMP/001
The following environmental risks have been identified:
Dust Fuel and oil spillage Spillage of Bitumen Smoke and vapor emissions Leaks from Storage Tanks Waste Material
Measures to control and minimize risks are in place and the monitoring of these controls remains the responsibility of all site personnel.
