tailieunhanh - Design Manual Metric 2009 Part 15

Tham khảo tài liệu 'design manual metric 2009 part 15', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Railroad overcrossings if requested by the railroad Slope protection is usually not provided under pedestrian structures. The type of slope protection is selected at the bridge preliminary plan stage. Typical slope protection types are concrete slope protection semi-open concrete masonry and rubble stone. 10 Slope Protection at Watercrossings The Olympia Service Center OSC Hydraulics Branch determines the slope protection requirements for structures that cross waterways. The type limits and quantity of the slope protection are shown on the bridge preliminary plan. 11 Protective Screening for Highway Structures The Washington State Patrol classifies the throwing of an object from a highway structure as an assault not an accident. Therefore records of these assaults are not contained in the Patrol s accident databases. Contact the region s Maintenance Engineer s office and the Washington State Patrol for the history of reported incidents. Protective screening might reduce the number of incidents but will not stop a determined individual. Enforcement provides the most effective deterrent. Installation of protective screening is analyzed on a case-by-case basis at the following locations On existing structures where there is a history of multiple incidents of objects being dropped or thrown and enforcement has not changed the situation. On a new structure near a school a playground or where frequently used by children not accompanied by adults. In urban areas on a new structure used by pedestrians where surveillance by local law enforcement personnel is not likely. On new structures with walkways where experience on similar structures within a kilometer radius indicates a need. On structures over private property that is subject to damage such as buildings or power stations. In most cases the installation of a protective screen on a new structure can be postponed until there are indications of need. Submit all proposals to install protective screening on .