Shear behavior of fiber-reinforced concrete hollow-core slabs under elevated temperatures
Experimental results of shear investigations on six hollow-core slabs with and without fibers cast by the extrusion method and tested under elevated temperatures are presented here. The purpose is to investigate shear behavior of precast/prestressed concrete hollow-core (PCHC) slabs using different...
Saved in:
Main Authors: | , , |
---|---|
Other Authors: | |
Format: | Article |
Language: | English |
Published: |
2022
|
Subjects: | |
Online Access: | https://hdl.handle.net/10356/162320 |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Institution: | Nanyang Technological University |
Language: | English |
id |
sg-ntu-dr.10356-162320 |
---|---|
record_format |
dspace |
spelling |
sg-ntu-dr.10356-1623202022-10-14T05:46:50Z Shear behavior of fiber-reinforced concrete hollow-core slabs under elevated temperatures Nguyen, Hang T. N. Li, Ye Tan, Kang Hai School of Civil and Environmental Engineering School of Materials Science and Engineering Engineering::Civil engineering Polypropylene Fibers Shear Behavior Experimental results of shear investigations on six hollow-core slabs with and without fibers cast by the extrusion method and tested under elevated temperatures are presented here. The purpose is to investigate shear behavior of precast/prestressed concrete hollow-core (PCHC) slabs using different types of fiber and fiber contents to resist fire effects. Three types of fiber including polypropylene (PP), hooked steel, and high-strength/straight steel fibers were employed. Two volume fractions of PP fibers (0.11 and 0.22%) and of steel fibers (0.51 and 0.89%) were examined. The effectiveness of PP fibers and steel fibers with different contents on structural performance of fire-exposed hollow-core slabs was quantified. Experimental results showed that the use of PP fibers increased resistance of concrete to explosive spalling, while resistance to load and elevated temperatures was substantially enhanced with the use of steel fibers. In addition, web-shear failure at an early stage of fire exposure was observed in all specimens without fibers and those with only PP fibers, exhibiting premature/brittle behavior. However, with the use of steel fibers, failure mode shifted from web-shear to flexural-shear or even flexural failure. Ductility and toughness of steel-fiber specimens subjected to elevated temperatures were also significantly enhanced. Test results from the experimental studies were then used to verify finite element (FE) models that simulated fire behavior of PCHC slabs with and without fibers. Good agreement between the test results and the FE models in terms of furnace temperature at failure, maximum deflection, and failure mode was obtained, thus verifying the numerical models. The verified FE models were then used to investigate web-shear mechanism of PCHC slabs exposed to fire. It is shown that temperature-induced tensile stresses in concrete webs (instead of temperature-induced reduction in strength of concrete and strands) governed web-shear behavior of PCHC slabs under elevated temperatures. Ministry of National Development (MND) National Research Foundation (NRF) The first author recognizes the support of the National University of Civil Engineering (NUCE), Vietnam for granting the first author a sabbatical leave to conduct this research project at the Nanyang Technological University, Singapore. The research presented in this paper was financially supported by the Singapore Ministry of National Development and National Research Foundation (Singapore) under L2 NIC Award No. L2NICCFP1-2013-4. 2022-10-13T07:54:30Z 2022-10-13T07:54:30Z 2021 Journal Article Nguyen, H. T. N., Li, Y. & Tan, K. H. (2021). Shear behavior of fiber-reinforced concrete hollow-core slabs under elevated temperatures. Construction and Building Materials, 275, 121362-. https://dx.doi.org/10.1016/j.conbuildmat.2020.121362 0950-0618 https://hdl.handle.net/10356/162320 10.1016/j.conbuildmat.2020.121362 2-s2.0-85100244875 275 121362 en L2NICCFP1-2013-4 Construction and Building Materials © 2020 Published by Elsevier Ltd. All rights reserved. |
institution |
Nanyang Technological University |
building |
NTU Library |
continent |
Asia |
country |
Singapore Singapore |
content_provider |
NTU Library |
collection |
DR-NTU |
language |
English |
topic |
Engineering::Civil engineering Polypropylene Fibers Shear Behavior |
spellingShingle |
Engineering::Civil engineering Polypropylene Fibers Shear Behavior Nguyen, Hang T. N. Li, Ye Tan, Kang Hai Shear behavior of fiber-reinforced concrete hollow-core slabs under elevated temperatures |
description |
Experimental results of shear investigations on six hollow-core slabs with and without fibers cast by the extrusion method and tested under elevated temperatures are presented here. The purpose is to investigate shear behavior of precast/prestressed concrete hollow-core (PCHC) slabs using different types of fiber and fiber contents to resist fire effects. Three types of fiber including polypropylene (PP), hooked steel, and high-strength/straight steel fibers were employed. Two volume fractions of PP fibers (0.11 and 0.22%) and of steel fibers (0.51 and 0.89%) were examined. The effectiveness of PP fibers and steel fibers with different contents on structural performance of fire-exposed hollow-core slabs was quantified. Experimental results showed that the use of PP fibers increased resistance of concrete to explosive spalling, while resistance to load and elevated temperatures was substantially enhanced with the use of steel fibers. In addition, web-shear failure at an early stage of fire exposure was observed in all specimens without fibers and those with only PP fibers, exhibiting premature/brittle behavior. However, with the use of steel fibers, failure mode shifted from web-shear to flexural-shear or even flexural failure. Ductility and toughness of steel-fiber specimens subjected to elevated temperatures were also significantly enhanced. Test results from the experimental studies were then used to verify finite element (FE) models that simulated fire behavior of PCHC slabs with and without fibers. Good agreement between the test results and the FE models in terms of furnace temperature at failure, maximum deflection, and failure mode was obtained, thus verifying the numerical models. The verified FE models were then used to investigate web-shear mechanism of PCHC slabs exposed to fire. It is shown that temperature-induced tensile stresses in concrete webs (instead of temperature-induced reduction in strength of concrete and strands) governed web-shear behavior of PCHC slabs under elevated temperatures. |
author2 |
School of Civil and Environmental Engineering |
author_facet |
School of Civil and Environmental Engineering Nguyen, Hang T. N. Li, Ye Tan, Kang Hai |
format |
Article |
author |
Nguyen, Hang T. N. Li, Ye Tan, Kang Hai |
author_sort |
Nguyen, Hang T. N. |
title |
Shear behavior of fiber-reinforced concrete hollow-core slabs under elevated temperatures |
title_short |
Shear behavior of fiber-reinforced concrete hollow-core slabs under elevated temperatures |
title_full |
Shear behavior of fiber-reinforced concrete hollow-core slabs under elevated temperatures |
title_fullStr |
Shear behavior of fiber-reinforced concrete hollow-core slabs under elevated temperatures |
title_full_unstemmed |
Shear behavior of fiber-reinforced concrete hollow-core slabs under elevated temperatures |
title_sort |
shear behavior of fiber-reinforced concrete hollow-core slabs under elevated temperatures |
publishDate |
2022 |
url |
https://hdl.handle.net/10356/162320 |
_version_ |
1749179187784056832 |