Creep of prestressing steels in fire

被引：22

作者：

Gales, John ^{[1
]}

Robertson, Lucie ^{[2
]}

Bisby, Luke ^{[3
]}

机构：

[1] Carleton Univ, Ottawa, ON, Canada

[2] Mott MacDonald, Glasgow, Lanark, Scotland

[3] Univ Edinburgh, Fire & Struct, Edinburgh, Midlothian, Scotland

来源：

FIRE AND MATERIALS | 2016年 / 40卷 / 07期

基金：

加拿大自然科学与工程研究理事会;

关键词：

high temperature creep; prestressing steel; optical strain measurement; necking; chemical composition; metallurgy; TENSIONED CONCRETE SLABS; DEFORMATION;

D O I：

10.1002/fam.2345

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

When prestressing steel (PS) is applied as continuous unbonded tendons within concrete, as in the case of post-tensioned (PT) construction, localized damage to the tendons may affect the integrity of the entire structure. When fire exposed, unbonded PT concrete structures are prone to tendon rupture because of a complex relaxation and strength reduction relationship influenced by high temperature PS creep. Explicit consideration of creep is necessary for the fire safe design of such buildings. High temperature PS creep has received limited research: few models can be used within the expected service stress range; none reliably model tertiary creep; and no studies are available investigating the influences of metallurgy on high temperature PS creep. A BS 5896 PS creep model is developed and validated. This model is used to provide PS failure insights at high temperatures. This understanding can be used to build validated models of structural fire experiments on PT concrete structural elements and to develop defensible, validated structural models that are essential towards performance based structural fire design of such systems. Finally, the high temperature creep performance of equivalent PS from different mills is compared, demonstrating strong influence of manufacturing and alloying techniques used. Future research is discussed. Copyright (c) 2015 John Wiley & Sons, Ltd.

引用

页码：875 / 895

页数：21

共 37 条

[1]

[Anonymous], 2003, A416 ASTM

[2]

[Anonymous], 1965, A416 ASTM

[3]

[Anonymous], 2007, 4672 ASNZS

[4]

ASTM, 2012, E119 ASTM

[5]

Bailey C, 2009, J Struct Eng, V87, P23

[6] Fire tests on unbonded post-tensioned one-way concrete slabs [J].

Bailey, C. G. ;

Ellobody, E. .

MAGAZINE OF CONCRETE RESEARCH, 2009, 61 (01) :67-76

[7]

Bisby L, 2014, NIST SPECIAL PUBLICA

[8]

BSi, 2012, 589612 BSI

[9]

CEN, 2004, EN 1992-1-2:2004 Eurocode 2: Design of concrete structures-Part 1-2: Structural fire design

[10]

Clark N., 1953, P I CIVIL ENG PT 1, V2, P107, DOI 10.1680/iicep.1953.11028.

← 1 2 3 4 →