- Library Home /
- Search Collections /
- Open Collections /
- Browse Collections /
- UBC Theses and Dissertations /
- Plastic shrinkage in dry mix shotcrete
Open Collections
UBC Theses and Dissertations
UBC Theses and Dissertations
Plastic shrinkage in dry mix shotcrete Campbell, Kevin Neil
Abstract
Plastic shrinkage cracking of dry-mix shotcrete is a common problem encountered within the construction industry. Dry-mix shotcrete is used in a wide variety of applications most commonly, the repair and rehabilitation of deteriorated concrete structures. Dry-mix shotcrete is also used as a tunnel liner, for slope stabilization, and for refractory applications. Plastic shrinkage cracks pose a significant threat to the durability and aesthetic appeal of shotcrete structures. This work was intended to develop a simple test used to study restrained plastic shrinkage in shotcrete overlays. Plastic shrinkage cracking of bonded dry-mix shotcrete overlays subjected to a severe drying environment is investigated. A novel test method was developed to study the effects of fibers and various admixtures on restrained plastic shrinkage. Shotcrete is cast directly onto fully matured, roughened sub-base that provides dimensional restraint. The assembly is immediately transferred to a drying chamber where plastic shrinkage cracking is monitored under controlled conditions. It is found that this method is effective in estimating the potential and degree of plastic shrinkage cracking in shotcrete, and also in assessing the effectiveness of various fiber types and admixtures. Steel and synthetic fibers were found to delay the formation of plastic shrinkage cracks as well as substantially reduce both the amount and width of cracking.
Item Metadata
Title |
Plastic shrinkage in dry mix shotcrete
|
Creator | |
Publisher |
University of British Columbia
|
Date Issued |
1999
|
Description |
Plastic shrinkage cracking of dry-mix shotcrete is a common problem encountered within the
construction industry. Dry-mix shotcrete is used in a wide variety of applications most
commonly, the repair and rehabilitation of deteriorated concrete structures. Dry-mix
shotcrete is also used as a tunnel liner, for slope stabilization, and for refractory applications.
Plastic shrinkage cracks pose a significant threat to the durability and aesthetic appeal of
shotcrete structures. This work was intended to develop a simple test used to study
restrained plastic shrinkage in shotcrete overlays.
Plastic shrinkage cracking of bonded dry-mix shotcrete overlays subjected to a severe drying
environment is investigated. A novel test method was developed to study the effects of
fibers and various admixtures on restrained plastic shrinkage. Shotcrete is cast directly onto
fully matured, roughened sub-base that provides dimensional restraint. The assembly is
immediately transferred to a drying chamber where plastic shrinkage cracking is monitored
under controlled conditions. It is found that this method is effective in estimating the potential
and degree of plastic shrinkage cracking in shotcrete, and also in assessing the
effectiveness of various fiber types and admixtures. Steel and synthetic fibers were found to
delay the formation of plastic shrinkage cracks as well as substantially reduce both the
amount and width of cracking.
|
Extent |
14249672 bytes
|
Genre | |
Type | |
File Format |
application/pdf
|
Language |
eng
|
Date Available |
2009-06-16
|
Provider |
Vancouver : University of British Columbia Library
|
Rights |
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
|
DOI |
10.14288/1.0050144
|
URI | |
Degree | |
Program | |
Affiliation | |
Degree Grantor |
University of British Columbia
|
Graduation Date |
1999-11
|
Campus | |
Scholarly Level |
Graduate
|
Aggregated Source Repository |
DSpace
|
Item Media
Item Citations and Data
Rights
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.