Alberta Bridge Maximum Loads

[liv4air]

Hey Guys

I'm trying to put a signage plan together for a newly installed bridge and our structural engineer is offsite for next week. I'll obviously followup with him prior to implementing, but was hoping someone could steer me in the right direction.

We have constructed a bridge on an oil site in Northern Alberta and utilized a CL-800 load design. My understanding is that in Alberta, bridge signage is required to state the following maximum loads:

CS1 (Single Axle)
CS2 (Tandem Axle)
CS3 (Tridem Axle)

As the bridge was designed for a CL-800 class truck, the CS3 value would be 80 metric tonnes.

How would I determine the values for a CS1 and CS2 class truck based on the design criteria for a CS3 truck?

Thanks
Johnny

 

[BridgeSmith]

Let me start with the disclaimer that I'm not familiar with the Canadian regulations or design truck configurations. However, if they're similar to the US design trucks, I don't think you can make a direct correlation in rated capacity, since the axle weights and spacings are different. For our designs, the ratings for the legal load trucks is done as part of the design, but those rated capacities do not have to be posted unless they fall well below the weight of the rating trucks (a rating factor well below 1.0), which would be very unusual for a new bridge.

All that to say, I would suggest a first step is to contact the designer and see if they have, or could provide, rated capacities (ratings) for the other truck configurations. Assuming those rated capacities are more than weight of the rating trucks (rating factors > 1.0), which is very likely the case, I would confirm that the bridge does actually have to be posted.

 

[Lomarandil]

HotRod is spot on.

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The name is a long story -- just call me Lo.