Assessment of Shear Stresses from Shrinkage and Thermal Deformation in Wood-Concrete Bridge Beams

AbstractThe aim of the paper is to assess the values of shear (delaminating) stress in the composition plane between the concrete (RC) deck slab and wood girder from concrete shrinkage, and shrinkage and swelling of wood, as well as difference in temperature between the wood web and concrete slab.

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Chloride Testing of 27-Vear-Old Prestressed Concrete Bridge Beams

PCI Journal ◽

10.15554/pcij.09011992.68.79 ◽

1992 ◽

Vol 37 (5) ◽

pp. 68-79 ◽

Cited By ~ 2

Author(s):

Valerie E. Murray ◽

Gregory C. Frantz

Keyword(s):

Prestressed Concrete ◽

Concrete Bridge ◽

Bridge Beams ◽

Prestressed Concrete Bridge

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Large-Size Jointless Concrete Slab-on-Grade with Combined Prestressing

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.309.201 ◽

2020 ◽

Vol 309 ◽

pp. 201-207

Author(s):

Andrei V. Tur

Keyword(s):

Rational Design ◽

Structural Reliability ◽

Concrete Slab ◽

Theoretical Background ◽

Shear Stresses ◽

Ground Floor ◽

Flat Slabs ◽

Large Size ◽

Floor Slabs ◽

Post Tensioned

In the international and national practice of design, a different type of slab on the various types of grade are becoming increasingly common. For such structural elements, shrinkage and temperature influences in combination with low tensile stress, mainly in early age, leads to the risk of cracking in reinforced concrete structures, and as result, a reduction of its durability. The present article describes some of the possible ways of usage of the post-tensioned flat slabs and the rational design procedures to provide their structural reliability. The theoretical background of the punching resistance checking, in the case when the piles support the foundation post-tensioned slabs, presented. For ground floor slabs, an iterative method is given for determining design compression pre-stresses distribution in slab sections, taking into account the restrained effect created by the friction shear stresses in contact between the slab and the base. Besides, the article presents some practical implementations of the post-tensioned slabs as an artificial base in the presence of weak soils and as a large-size ground floor (slab-on-grade) without any joints.

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GPR detection of voids in post-tensioned concrete bridge beams

10.1117/12.462217 ◽

2002 ◽

Cited By ~ 3

Author(s):

Antonios Giannopoulos ◽

Paul Macintyre ◽

Scott Rodgers ◽

Mike C. Forde

Keyword(s):

Concrete Bridge ◽

Bridge Beams ◽

Post Tensioned

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Influence of Early Age Volume Changes on Long-Term Concrete Shrinkage

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1610-05 ◽

1998 ◽

Vol 1610 (1) ◽

pp. 28-32 ◽

Cited By ~ 4

Author(s):

Erika E. Holt ◽

Donald J. Janssen

Keyword(s):

Concrete Slab ◽

Drying Shrinkage ◽

Early Age ◽

Volume Changes ◽

Test Procedures ◽

Cracking Behavior ◽

Concrete Shrinkage ◽

Cracking Potential ◽

Partially Restrained

Volume changes can occur in concrete during the first 24 hr and are generally missed in laboratory shrinkage evaluations. Unfortunately these early age volume changes are present in real pavements and structures and can contribute to the cracking behavior of the concrete at later ages. Early age volume changes can occur in two forms: drying shrinkage before the start of curing and autogenous volume changes. Although these early age volume changes are often dismissed as being insignificant, recent work in Europe has identified magnitudes for early age volume changes of some concretes that are equal to or greater than 28-day drying shrinkage measurements. Expansions have also been identified in some cases. The results of some investigations of volume changes in concrete during the first 24 hr under both drying and nondrying conditions are presented. An example of potential long-term cracking under partially restrained conditions (concrete slab-on-grade modeled by a concrete ring cast around a hollow steel ring) is used to illustrate the magnitude of influence of early age volume changes on concrete cracking. Both test procedures employ nonstandard methods to quantify the cracking potential of concrete.

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