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An Innovative and Sustainable Wet Joint Between Precast Beam and Columns from the Oil & Gas

  • V. Colone
  • P. Lopriore

Abstract

This innovative joint was conceived for the effective and sustainable construction of precast concrete pipe-rack structures in petrochemical plants. It consists in a cast-in-situ joint between precast beam and column concrete elements, featuring easy in-shop fabrication and on-site assembly, with no scaffolding and minimum formworks. The solution is characterized by high strength and ductile behaviour in the plastic range, by means of loop splices and cast-in-situ concrete with steel fibres. Experimental tests conducted on reduced-scale structures verified that the performance of the prefabricated solution during an earthquake is comparable to, if not better than, that of the corresponding cast-in-situ concrete solution, while fulfilling the American Concrete Institute requirements. This precast concrete solution economically mimics the behaviour of monolithic reinforced concrete frames and has been already successfully implemented in several pipe rack structures in remote seismic zones.

This innovative joint was conceived for the effective and sustainable construction of precast concrete pipe-rack structures in petrochemical plants. It consists in a cast-in-situ joint between…

What is the difference between dry joint and wet joint in precast segmental bridges?

Dry joints have been properly used in the past in which the bridge segments are formed by match casting. The prevalence in the past is due to it lower cost and time for construction. There is no gluing material to seal up the joint. As such, leakage through the joint into the box culvert occurs from time to time and this may affect the durability of external post-tensioning tendons. Moreover, owing to the effect of seismic, temperature and creep, the joints are found to open under these conditions. Spalling of top concrete slab at bridge joint was also reported.

Wet joint involves the use of epoxy glue at the mating precast segments. After the application of epoxy glue, a temporary precompression pressure of 0.3MPa is applied by stress bars at top, bottom and the sides of the mating precast segments. The epoxy sets under the applied pressure. The use of epoxy joints provides lubrication to help in the fit-up and alignment of the mating segments and minimizes the effect of hard point contact between segments.

What is the difference between dry joint and wet joint in precast segmental bridges? Dry joints have been properly used in the past in which the bridge segments are formed by match casting. The