Forensic investigations to evaluate sulfate-induced heave attack on a tunnel shotcrete liner

Puppala, AJ; Saride, S; Dermatas, D; Al-Shamrani, M; Chikyala, V

dc.contributor.author	Puppala, AJ	en
dc.contributor.author	Saride, S	en
dc.contributor.author	Dermatas, D	en
dc.contributor.author	Al-Shamrani, M	en
dc.contributor.author	Chikyala, V	en
dc.date.accessioned	2014-03-01T01:33:30Z
dc.date.available	2014-03-01T01:33:30Z
dc.date.issued	2010	en
dc.identifier.issn	0899-1561	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/20453
dc.subject	Ettringite	en
dc.subject	Gypsum	en
dc.subject	Limestone	en
dc.subject	Rock testing	en
dc.subject	Shotcrete	en
dc.subject	Sulfate heaving	en
dc.subject	Tunnels	en
dc.subject.classification	Construction & Building Technology	en
dc.subject.classification	Engineering, Civil	en
dc.subject.classification	Materials Science, Multidisciplinary	en
dc.subject.other	Comprehensive research	en
dc.subject.other	Energy dispersive X ray spectroscopy	en
dc.subject.other	Engineering tests	en
dc.subject.other	Ettringite formations	en
dc.subject.other	Ettringites	en
dc.subject.other	Forensic investigation	en
dc.subject.other	High strength	en
dc.subject.other	Indirect tensile strength	en
dc.subject.other	Potential loss	en
dc.subject.other	Powder material	en
dc.subject.other	Rock core	en
dc.subject.other	Rock materials	en
dc.subject.other	Rock testing	en
dc.subject.other	Shotcrete liners	en
dc.subject.other	Shotcretes	en
dc.subject.other	Sulfate heaving	en
dc.subject.other	Sulfate measurement	en
dc.subject.other	Triaxial test	en
dc.subject.other	Unconfined compression strength	en
dc.subject.other	Gypsum	en
dc.subject.other	Limestone	en
dc.subject.other	Rocks	en
dc.subject.other	Sewer linings	en
dc.subject.other	Tensile strength	en
dc.subject.other	X ray powder diffraction	en
dc.subject.other	X ray spectroscopy	en
dc.subject.other	Shotcreting	en
dc.subject.other	anhydrite	en
dc.subject.other	gypsum	en
dc.subject.other	heave	en
dc.subject.other	hydration	en
dc.subject.other	limestone	en
dc.subject.other	liner	en
dc.subject.other	shotcrete	en
dc.subject.other	sulfate	en
dc.subject.other	tunnel	en
dc.subject.other	Dallas	en
dc.subject.other	Texas	en
dc.subject.other	United States	en
dc.title	Forensic investigations to evaluate sulfate-induced heave attack on a tunnel shotcrete liner	en
heal.type	journalArticle	en
heal.identifier.primary	10.1061/(ASCE)MT.1943-5533.0000087	en
heal.identifier.secondary	http://dx.doi.org/10.1061/(ASCE)MT.1943-5533.0000087	en
heal.language	English	en
heal.publicationDate	2010	en
heal.abstract	This paper presents the results of a comprehensive research study to determine the potential causes for an inordinate distress developed on a shotcrete liner material of a tunnel located near Dallas, TX. This tunnel was originally founded on a limestone material. Distress locations were identified where possible delamination of shotcrete layer and moisture leaks were either suspected or noticed. As a part of the research, rock cores and white powderlike substance behind the liner were collected around the distressed locations, and these cores and powder material were subjected to chemical, mineralogical, and engineering tests to understand the potential causes of this distress. Mineralogical tests, in particular, X-ray powder diffraction analysis on a powder material and gel-like substances collected on the liner, showed the presence of anhydrite, gypsum, and ettringite traces. High amounts of sulfate measurements in chemical and energy dispersive X-ray spectroscopy studies also showed that both gypsum and ettringite formations were possible in and around the limestone material. Upon hydration, mineral expansion of ettringite and anhydrite led to heaving and subsequent cracking of the adjacent shotcrete layer. Engineering characterization tests including unconfined compression strength (UCS), indirect tensile strength (ITS), and triaxial tests on rock cores embedded with a powder type sulfate material revealed that low strength cores were obtained near high distress zones and high strength cores were collected at low distress zones. The UCS values ranged from 6.2 (high distress) to 13.8 MPa (low distress) whereas the ITS values of the cores varied from 0.5 to 1.1 MPa for the same distress locations. This indicates the potential loss of strength of these rock materials from the presence of gypsum material in them. Possible methods to mitigate this heaving problem behind the liner are also discussed. © 2010 ASCE.	en
heal.publisher	ASCE-AMER SOC CIVIL ENGINEERS	en
heal.journalName	Journal of Materials in Civil Engineering	en
dc.identifier.doi	10.1061/(ASCE)MT.1943-5533.0000087	en
dc.identifier.isi	ISI:000280952200011	en
dc.identifier.volume	22	en
dc.identifier.issue	9	en
dc.identifier.spage	914	en
dc.identifier.epage	922	en