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slab pour sequence
i have a 3 span horizonlly curve bridge designed by using mdx. i have to provide a slab pour sequence information ,so what is the methodology to do that? i totally have no idea.
thank you for your help
check out the particular state dot where you are performing the work. they often have a series of sequences available for use by designers.
note that just because one is specified, the contractor is often allowed to place the deck end to end if the bridge is sufficiently small enough. i've never had a problem with a three span bridge.
aun:
if i understand correctly, you have your beams ready and what is missing is the pouring of the slab.
two points: the main reinforcement of the slab is radial (or perpendicular to traffic), and in the two central supports, fixed or not to the columns, there must be some negative longitudinal reinforcement distributed in the slab.
avoid suspending the pouring of the concrete -which is radial- in the points of maximum moment or shear.
so, let us say that such negative reinforcement has a length .22l each side of the supports and that the spans are l1, l2 and l3.
you could follow the sequence: pour the concrete from .8l1 to the beginning of l1. go from the other side and pour the concrete from .8l1 to the end of l3.
if there is problem, for example due to weather , in this second stage, you could go from .8l1 to .2l2 and then , from there to .8l2 and afterwards to .2l3 and finally to the end of l3 ( i hope it is not confusing).
with these alternatives, it is possible to have two teams of workers going in opposite directions.
if you want, you also can go in one sense only, following similar steps.
the constructor will not have much problem in jointing the old to the new concrete, because it is easy to give roughness to the old concrete and besides, additional to the negative reinforcement, there are distributional longitudinal reinforcement at the top and bottom of the slab鈥?but if doubts persist, use additives. |
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