|Table of Contents|

Axial Force Analysis of Restrained Concrete Beams During Heating and Cooling Phases(PDF)

《建筑科学与工程学报》[ISSN:1673-2049/CN:61-1442/TU]

Issue:
2010年01期
Page:
12-20
Research Field:
Publishing date:
2010-03-20

Info

Title:
Axial Force Analysis of Restrained Concrete Beams During Heating and Cooling Phases
Author(s):
WU Bo;  QIAO Chang-jiang
State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510640, Guangdong, China
Keywords:
reinforced concrete;  restrained beam;  axial force;  heating phase;  cooling phase
PACS:
TU375
DOI:
-
Abstract:
Using the program SAFIR, the influences of some parameters, including axial restraint stiffness ratio, section width, reinforcement ratio, and heating time, etc. on axial forces in restrained concrete beams exposed to ISO 834 standard fire with cooling phase, which compared with those fire without cooling phase were analyzed. Based on the simulation results of 288 cases, a practical calculation method for axial forces in restrained concrete beams subjected to fire with cooling phase was proposed. The results show that for axially-and-rotationally restrained beams in fire with or without cooling phase, the axial force ratio increases gradually first, then varies gently, and finally decreases quickly, but the gentle variation stage related to fire with cooling phase is longer than that without cooling phase; the influences of rotational restraint stiffness ratio, section height, beam span and load ratio on the axial force ratio of axially-and-rotationally restrained beams subjected to fire with cooling phase are limited, while the peak value of the axial force ratio increases with increasing of the axial restraint stiffness ratio and reinforcement ratio or with decreasing of section width; and the effect of concrete cover on the axial force ratio of axially-and-rotationally restrained beams can be neglected approximately.

References:

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Memo:
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Last Update: 2010-03-20