摘要: |
A review was undertaken to understand the basis of the current and any future specification for treatments on structures, applicable to Transport Scotland requirements but also to inform future guidance issued by the National Winter Service Research Group (NWSRG). The review has identified a range of solid and liquid de-icers applied for bridge treatments and corrosion sensitive structures in the UK and worldwide, but special arrangements and non-corrosive de-icers are not always specified for winter service. The review has identified that treatments with sodium chloride brine and salt are used on many structures, including major suspension and cable stayed bridges, without significant adverse effect with reliance on protection techniques and construction to prevent corrosion. This will critically depend on the construction, protection measures and maintenance practices followed. Modern standards and protection measures have improved significantly, mitigating the risk of impacts from de-icing treatments, and key factors impacting the bridge susceptibility are identified in the review. A comparison was made between the real cost of treatments with salt and potassium acetate. The analysis indicated that acetate starts to gain positive benefit if its reduction of damage cost can reach 50% of the salt damage cost. The use of potassium acetate requires a significant additional de-icer cost; however, this analysis may indicate that the overall resulting cost - benefit may be positive from the reduction in damage costs. |