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Bridge/Channel Survey
Posted by FrancisH on March 3, 2017 at 3:39 amHow do you execute a bridge survey that spans a channel?
The water crossing is about 6km in width.
Question i how do you set the positions of the piers from shore?FrancisH replied 7 years, 6 months ago 4 Members · 4 Replies -
4 Replies
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FrancisH, post: 416626, member: 10211 wrote: How do you execute a bridge survey that spans a channel?
The water crossing is about 6km in width.
Question i how do you set the positions of the piers from shore?Do you have a boat? How fast is the water moving? What is/are the diameter(s) of the piers? If you do and the water is moving slow enough to safely approach the piers, can you build a rig to attach a prism to the piers and take offset shots?
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Like this
http://www.newnybridge.com/coming-together-main-span-and-rockland-approach-now-linked/
5.2Km Tappan Zee Bridge across a River -
If you have 24 minutes .. here’s “my” now 20yr. old 13km. baby. The short answer is shore based total station for the approach piers and gps for the strait and navigation piers. The approaches were relatively shallow so they constructed a temporary causeway from the shore to the approach piers. In the straits it was all gps.
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Peter Hughes-Davies, post: 416656, member: 48 wrote: If you have 24 minutes .. here’s “my” now 20yr. old 13km. baby. The short answer is shore based total station for the approach piers and gps for the strait and navigation piers. The approaches were relatively shallow so they constructed a temporary causeway from the shore to the approach piers. In the straits it was all gps.
So for the strait piers, you mark it while on a platform/boat? Just wondering how do you get cm accuracy level for construction to mark pier positions?
Or is it a repetitive process with accuracy getting better until they get a construction platform in place?
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