Design guidelines for sole plates in the elastomeric bearing system

Design of elastomeric bearing system and analysis of it mechanical properties

KSME International Journal ◽

10.1007/bf03028786 ◽

2004 ◽

Vol 18 (1) ◽

pp. 20-29 ◽

Cited By ~ 1

Author(s):

Byung-Young Moon ◽

Gyung-Ju Kang ◽

Beom-Soo Kang ◽

Dae-Seung Cho

Keyword(s):

Mechanical Properties ◽

Elastomeric Bearing ◽

Bearing System

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Finite element analysis of multirecess hybrid spherical journal bearing system

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650119884829 ◽

2019 ◽

Vol 234 (11) ◽

pp. 1798-1821

Author(s):

Adesh K Tomar ◽

Satish C Sharma

Keyword(s):

Finite Element ◽

Journal Bearing ◽

Design Guidelines ◽

Numerical Results ◽

Fluid Film ◽

Frictional Torque ◽

Element Analysis ◽

Fluid Film Thickness ◽

Film Stiffness ◽

Bearing System

The present work deals with finite element method analysis of a multirecess hybrid spherical journal bearing system. The governing equations have been discretized using Galerkin’s technique and are solved simultaneously using a suitable iterative technique. The effect of span angle on the static and dynamic behavior of a hybrid spherical journal bearing compensated with membrane restrictor is investigated in the present work. Numerical results indicate that larger values of span angle provide enhanced value of minimum fluid-film thickness [Formula: see text], reduced lubricant flow requirement [Formula: see text], and higher value of frictional torque [Formula: see text]. Further, the results have been compared with a correspondingly similar capillary-compensated bearing. The comparison of numerically results demonstrates that the value of direct fluid-film stiffness coefficient [Formula: see text] could be 45.90% higher than that of correspondingly similar capillary-compensated bearing. The numerical results presented in this work may be useful as design guidelines for a recessed hybrid spherical journal bearing.

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Flexural design of precast, prestressed ultra-high-performance concrete members

PCI Journal ◽

10.15554/pcij65.6-02 ◽

2020 ◽

Vol 65 (6) ◽

pp. 35-61

Author(s):

Chungwook Sim ◽

Maher Tadros ◽

David Gee ◽

Micheal Asaad

Keyword(s):

Prestressed Concrete ◽

High Performance ◽

High Performance Concrete ◽

Limit State ◽

Design Guidelines ◽

Design Tool ◽

Supplementary Cementitious Materials ◽

Ultra High Performance Concrete ◽

Concrete Members ◽

Cylinder Strength

Ultra-high-performance concrete (UHPC) is a special concrete mixture with outstanding mechanical and durability characteristics. It is a mixture of portland cement, supplementary cementitious materials, sand, and high-strength, high-aspect-ratio microfibers. In this paper, the authors propose flexural design guidelines for precast, prestressed concrete members made with concrete mixtures developed by precasters to meet minimum specific characteristics qualifying it to be called PCI-UHPC. Minimum specified cylinder strength is 10 ksi (69 MPa) at prestress release and 18 ksi (124 MPa) at the time the member is placed in service, typically 28 days. Minimum flexural cracking and tensile strengths of 1.5 and 2 ksi (10 and 14 MPa), respectively, according to ASTM C1609 testing specifications are required. In addition, strain-hardening and ductility requirements are specified. Tensile properties are shown to be more important for structural optimization than cylinder strength. Both building and bridge products are considered because the paper is focused on capacity rather than demand. Both service limit state and strength limit state are covered. When the contribution of fibers to capacity should be included and when they may be ignored is shown. It is further shown that the traditional equivalent rectangular stress block in compression can still be used to produce satisfactory results in prestressed concrete members. A spreadsheet workbook is offered online as a design tool. It is valid for multilayers of concrete of different strengths, rows of reinforcing bars of different grades, and prestressing strands. It produces moment-curvature diagrams and flexural capacity at ultimate strain. A fully worked-out example of a 250 ft (76.2 m) span decked I-beam of optimized shape is given.

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