FE ANALYSES OF EXPERIMENTS FOR SHEAR PROPERTIES OF RUBBER BEARINGS WITH PARAMETERS OF AXIAL STRESS PARAMETERS AND EVALUATION OF LOCAL INTERNAL STRESS OF RUBBER BEARINGS

Comprehensively considering the positive contribution of energy conservation and the reduction of the construction skill requirement for workers, a new type of interlocking hollow block using recycled aggregates concrete (IHAC) with the compressive strength defined as MU10 was proposed, which could help improve more than 56% of the construction efficiency compared to common used concrete hollow blocks. In order to study the shear properties and promote its application in building engineering, the shear strength of 10 groups (three specimens for each group) of masonries considering different axial stress level and whether or not to use concrete in the grouting holes were studied, and the failure mode as well as the shear strength of the masonries were analyzed. And then, the calculation formulas for predicting the shear strength of the IHAC masonry were obtained by using the parameter fitting method based on the Coulomb failure theory, which could well reflect the parabolic shaped changing characteristic of the shear strength with the increasing of the axial stress, and the maximum difference was within 18% between the calculated and test results.

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Development of an Evaluation Method for Seismic Isolation Systems of Nuclear Power Facilities: Part 8 — Fundamental Properties of Full-Scale Lead Rubber Bearings Based on Breaking Test

Volume 8: Seismic Engineering ◽

10.1115/pvp2014-29006 ◽

2014 ◽

Cited By ~ 1

Author(s):

Nobuhisa Sato ◽

Takashi Nakayama ◽

Takashi Kaneko ◽

Seiji Nagata ◽

Tetsuo Imaoka ◽

...

Keyword(s):

Nuclear Power ◽

Seismic Isolation ◽

Evaluation Method ◽

Axial Stress ◽

Tensile Force ◽

Full Scale ◽

Fundamental Properties ◽

Lead Rubber Bearings ◽

Rubber Bearings ◽

Seismic Isolation Systems

This paper provides a part of the series “Development of an Evaluation Method for Seismic Isolation Systems of Nuclear Power Facilities.” This part shows the fundamental properties of full-scale lead rubber bearings with 1600 mm diameter based on break tests. The following results are mainly obtained. One: The deformations and the acting loads of the full-scale specimens were accurately obtained up to break by the measurement system for the break tests. Two: The fundamental properties for the full-scale lead rubber bearings with a large-diameter lead plug were obtained by the basic property tests. The load-displacement relations were stable and similar basic properties were obtained among the specimens. Three: The result of shear break tests showed that the hardening property of the specimens had a certain harmony with the hardening stiffness model which was used in the seismic response analysis to investigate the safety margin for severe earthquakes beyond design basis earthquakes of nuclear power facilities. The effect of axial pressure on hardening property was not specifically observed. The evaluated linear strain limit was larger than 250% for every specimen. Four: The softening property of the specimens was obtained from the tensile break tests. The axial stress of tensile yield was approx. 1.4 MPa and the axial stress did not show any negative gradient at least up to approx. 10% axial strain after the tensile yield even with offset shear strains. Five: The tensile force acting on the bolts which secure the specimen to the testing machine was lower than the estimated tensile force at shear break, which indicates tensile force was conservatively calculated to maintain safety in the design for foundation of lead rubber bearings.

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