Stress Relaxation of Tufted Carpets and Carpet Components

Dimensional stability of tufted carpets has been a continuing problem in the industry for years. When a tufted carpet is installed by the stretch method, it experiences stress relaxation over time which can cause the carpet to buckle, wrinkle and become loose with the only option being a costly re-stretching of the carpet. Since woven carpets seldom require re-stretching, the carpet buckling problem seems to be linked primarily to the tufted construction. This research seeks to analyze the various components of the tufted carpet composite structure and identify the role each component plays in the phenomenon of stress relaxation. Since a carpet is always stretched in both dimensions simultaneously during installation, understanding its biaxial stress decay is important. To this end, a biaxial loading system has been used to test various samples of the primary backing alone (before tufting), primary backing after tufting (with tufts), the secondary backing alone, and the finished carpet after attaching the backings with various binder weights per area. The four variables under consideration include: primary and secondary backing constructions, tufting density, and latex weight, with the secondary backing and latex weight expected to have the greatest effects on stress decay. In order to collect the most information, the biaxial test system was connected to a computer-based data acquisition system to continuously monitor stress levels and generate stress relaxation curves over a 20-hour testing period. A viscoelastic model that included representations of each component in the carpet structure was used to analyze and understand the influence of the components on the stress relaxation of carpets.

Author dc:creator

• Phillips, Kristie Jo

Advisors dc:contributor.advisor

• Tushar K. Ghosh, Committee Chair
• William Oxenham, Committee Member
• Samuel C. Winchester, Committee Member
• David A. Dickey, Committee Member

• carpet structure
• stress relaxation
• carpet
• tufting
• tufted primary
• stress decay over time
• load decay
• laminated composites
• primary backing
• secondary backing
• tufted carpets
• viscoelastic modeling

Statement dc:rights

• I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to NC State University or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.

Dc Identifier Other

etd-10162002-173021

OAI record oai:identifier

https://repository.lib.ncsu.edu/server/oai/request?verb=GetRecord&metadataPrefix=dim&identifier=oai%3Arepository.lib.ncsu.edu%3A1840.16%2F3555