Evaluation of elastomeric bearing performance at low temperatures

Recent studies on elastomeric bearings led to changes in the design specifications, which tend to indicate that bearings fabricated in the past, would fail the current test requirements. This is contrary to the fact that there have been no reported problems of poor bearing performance in low-temperature regions. AASHTO requires low-temperature tests to determine the change in the shear modulus, which is limited to a certain value. This criterion does not adequately address the performance of the bearings, because in-service conditions of an elastomeric bearing are not sufficiently taken into account. The field performance of the bearings depends primarily on the temperature characteristics of the geographic location where the bearing is installed, which also determines the probable amplitude of shear strain the bearing would experience. Thus, to adequately evaluate the in-service performance of the bearings, a performance-based procedure should be employed. In this paper, a variety of bearings were tested and checked at four different low-temperature locations. The test results have been reported in a companion paper. It was established that most of the bearings could in fact serve satisfactorily in spite of the fact that the bearings in many instances fail the current test procedures. This indicates that the current testing requirements related to cold-temperature performance are too severe. Hence, a procedure that relies on the historic temperature records of the region where the bearing would be installed is recommended to determine the performance requirements at a particular location. In this procedure, the acceptance criterion is based on the maximum expected shear force and the potential slip of the bearings.


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Vertical cracks, termed "pre-release cracks," beginning at the top flange and propagating downward into the section depth have been observed to develop during the production of long-span prestressed concrete bridge girders. The cracking which is attributed to the restrained shrinkage the concrete and thermal effects during the curing period prior to release of the prestressing strands, tends to be more critical for long-span girders with deep sections and large amounts of prestressing strands. Studies were ...
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Topkaya, Cem (American Society of Civil Engineers (ASCE), 2002-06-01)
The shear modulus of the elastomer is the most important material property related to the behavior of elastomeric bearings used principally at supports in bridges. Current methods for determining the shear modulus usually require small test samples cut from manufactured bearings. Such tests are costly, do not necessarily represent the performance of the full-size bearing, and are destructive. A new shear test method, called the inclined compression test, is reported that is nondestructive and only requires ...
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Composite action between a reinforced concrete deck and steel girders is usually achieved by making use of welded headed shear studs. The mechanics of shear studs embedded in mature concrete has been investigated extensively in the past. Current literature, however, lacks experimental evidence of steel-concrete interface behavior at early concrete ages. This information is useful in understanding the behavior of bridges during construction. Current testing methods are not suitable for determining the respon...
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Baran, Eray; French, Catherine (Precast/Prestressed Concrete Institute, 2005-01-01)
Inconsistencies in the sectional response of prestressed concrete flanged sections predicted by the AASHTO LRFD and AASHTO Standard Specifications, including the maximum reinforcement limits, may arise due to different interpretations of the equivalent rectangular compressive stress block idealization. Strain compatibility analyses with nonlinear material properties were performed for a variety of non-rectangular prestressed concrete sections to identify the inconsistencies between the two specifications. R...
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The strength of expansive cement grout borehole plugs cast in rock cylinders is investigated theoretically and experimentally as a function of curing and testing temperature of the plugged rock cylinder and of borehole size. The distributions of thermally induced stresses and displacements, shear stresses along the plug-rock interface due to an axial stress applied to the plug, and resultant interfacial shear stresses due to a combination of uniform elevated temperature and axial load are studied and analys...
Citation Formats
A. Yakut, “Evaluation of elastomeric bearing performance at low temperatures,” JOURNAL OF STRUCTURAL ENGINEERING-ASCE, pp. 995–1002, 2002, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/48764.