Control of Horizontal Cracking in the Ends of Pretensioned Prestressed Concrete Girders

Abstract

This paper describes a limited investigation of the stresses which occur in the ends of pretensioned prestressed concrete girders at the time of transfer of prestress, and which can result in the formation of horizontal cracks in the ends of such girders. Also reported is a study of the stresses set up in vertical stirrup reinforcement near the ends of pretensioned prestressed girders when horizontal end cracking does occur. On the basis of experimental data obtained in this study, an equation is proposed for the design of vertical stirrup reinforcement necessary to restrict the size of any horizontal end cracks which may occur in a pretensioned prestressed concrete girder.

Análisis de los fenómenos de estallido y exfoliación en piezas prefabricadas pretensadas no convencionales

“…Correspondientes también a los años 60, las investigaciones de Marshall y Mattock (19), y de Arthur y Ganguli (20), obtuvieron expresiones que permitían calcular la cuantía de estribos necesaria para resistir las tracciones producidas en la zona de transferencia. En general, estos trabajos señalan que las fisuras aparecen entorno al centro de gravedad de las piezas o en las zonas de unión entre ala y alma, y se centran en el cálculo de la armadura transversal necesaria para controlar dicha fisuración.…”

Numerical study on the temporal changes of the principal stresses at the ends of the hollow PC-girders to control horizontal end cracks

“…If end zones are not kept from the horizontal crack occurrence, it may create corrosion concerns (2) . It was founded around the 1960s; horizontal cracks occur in the pretensioned member ends, Marshall and Mattock (12) investigated with an experimental study. After that, multiple researchers have done analytical studies (such as the Gergely-Sozen model, strut-and-tie models, and nonlinear finite element analysis) and experimental studies to realize the end-zone stresses or to design the end-zone reinforcements (5)(6)(7)(8)11,(13)(14)(15)(16)(17)(18) .…”

“…Furthermore,Figures 11,12, 13 and 14 show the maximum principal stress' temporal changes at the https://www.indjst.org/ end of the BS18 girder.…”

Accurate finite element modeling of pretensioned prestressed concrete beams

“…A survey of previous studies did not reveal any significant effort leading to better understanding of the actual state of stress in the anchor zone or end region of, especially, pretensioned prestressed beams. Some of the early studies did, however, investigate the effects of vertical reinforcement in such regions for the prevention of horizontal cracks [7][8][9][10][11]. For instance, Padmarajaiah and Ramaswamy [9] undertook experimental studies on such beams incorporating short steel fibers as supplemental reinforcement.…”