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Temporary post-tensioning

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Temporary post-tensioning bars are used in segmental balanced cantilever bridges construction. temporary post-tensioning used to hold the new segment in place and squeeze the epoxy joint until the main longitudinal post-tensioning is installed and stressed. the process of construction shall be arranged to left the segment, place the epoxy, install temporary post-tensioning and squeeze the joint before the expoy set. the number of post-tensioning bars depends on segment size but it ranges from 3 to 8 bars. temporary post-tensioning can be installed internally or externally. at least one bar shall be used for the wing of the segment. figure no:1 showing temporary external post-tensioning used to hold the precast segment until the main post-tensioning installed and stressed.




Figure 1
similarly, temporary post-tensioning will be used for span by span erection bridge type. temporary post-tensioning shall be used to hold precast segments in location and squeeze the epoxy joint until main post-tensioning installed and tensioned. 

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