This policy addresses deck closure pour and associated requirements for the following bridge superstructure types: • Cast-in-place (CIP) construction (slabs, box girders, and tee beams)
How should a bridge deck closure pour be positioned?
2015年9月23日 · When designing a steel girder bridge using phased construction with dead load deflections exceeding 2", my state (Nebraska, USA) requires a closure pour. No guidance is provided on how to locate or design the closure pour.
Closure pour — A concrete deck slab pour for the remaining deck between the widening or staged bridge and the existing bridge to accommodate the differential deflections caused by creep, shrinkage and elastic shortening.
Closure pours should be placed in areas with constant cross-slope in the bridge deck. In addition, closure pours over beams should be avoided. For large deflections it may be difficult for the contractor to match up the elevations of the construction joints without a closure pour.
Chapter 1 outlines key components, personnel, and procedures necessary for bridge deck construction. Following are a series of lists, guidelines, and questions to serve as frameworks for preconstruction planning:
As per NJA and JMW, a deck closure pour shall be used between phases for all Phased Bridge Construction projects and for all Bridge Widening projects. Closure pours shall be called out and detailed in the appropriate Plan of Span sheets and Typical Sections in the Bridge plans.
A concrete closure pour completes the deck connection and ties the individual units together in a manner that is intended to emulate monolithic behavior. Traditionally, different grouts as closure pour materials for the precast bridge deck system
Chapter 11: Selection of Durable Closure Pour Materials for …
370 Chapter 11 Selection of Durable Closure Pour Materials for Accelerated Bridge Construction 11.0 Introduction For precast bridge deck systems with cast-in-place (CIP) connections, precast elements are brought to the construction site ready to be set in place and quickly joined together.
pour sequences to help mitigate deck misalignment at joint closure pours, fabrication tolerances, the steel "fit-up" condition, and actual construction practices may affect the final result. This project focuses on identifying deck sequencing issues to provide better prediction of dead load deflections during bridge deck pours.
after the structural steel is erected but before the deck forms are built, elevations on the top flange of the girders are obtained at the points indicated in the table. THE DIFFERENCE BETWEEN THE ELEVATIONS OBTAINED AND THOSE IN THE TABLE IS THE ACTUAL BLOCKING DISTANCE FROM THE TOP OF THE GIRDER TO THE BOTTOM OF …