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Durability of hot rolled asphalt surfaces in bunker silos - Extended field trials - WA0808

WA0808. Durability of hot rolled asphalt surfaces in bunker silos - extended field trials.

Hot rolled asphalt (HRA) is currently promoted as a suitable material for resurfacing the floors of silos. Although HRA is claimed to be chemically resistant to silage effluent attack, its use in silos is relatively recent and its long term performance is unknown. A wide range of HRA mixes is available for different applications such as roads and paved areas; there is a need to evaluate the most suitable HRA mixes for use specifically in forage silo floors. This study, which forms an extension to the recently completed project WA0113, will evaluate the durability of 3 different HRA mixes under field conditions.

The study will be composed of 4 objectives outlined as follows, together with ways in which they might be achieved:
1. Monitoring of the condition of 3 different HRA mixes already laid as floor strips in silos on 2 commercial farms. A visual inspection will be undertaken of the parts of the silo floor that are accessible. When the silo is empty it will be cleaned in order to inspect whether any repairs are necessary. A diary of any faults or repairs to the HRA floor will be kept;
2. Obtaining data on the management practices relating to the silos on the 2 farms. Co-operating farmers will be asked to keep a diary of events such as dates of silage making and feeding. Samples of effluent will be taken soon after ensiling and analysed. Later in the year, silage samples will be taken for analysis and information will be collected about the herd size, feed usage, etc.;
3. Determination of the relative performance of the HRA mixes. Data relating to the surface profiles will be collated and analysed annually to update information on the relative performance of the 3 HRA strips in the 2 silos studied; and
4. Dissemination of results to the industry. Analysed data will be submitted to BSI, and findings of field trials will be published in the popular farming press and to HRA suppliers. Any findings will be incorporated into revisions of the MAFF/ADAS Construction Guidance Note (CGN) on silos. Results of the study should directly benefit farmers through provision of better information on more durable HRA mixes; this should result in lower silo maintenance costs. MAFF/DEFRA and the EA will indirectly benefit, as utilization of appropriate HRA mixes should result in less silo deterioration, hence fewer water pollution incidents from silage effluent.
Project Documents
• FRP - Final Report : Durability of hot rolled asphalt surfaces in bunker silos - Extended field trials   (715k)
Time-Scale and Cost
From: 2001

To: 2005

Cost: £32,604
Contractor / Funded Organisations
Environmental Protection              
Land Contamination              
Sustainable Production              
Fields of Study
Environmental Protection - Agriculture