Contour profile quality affects tunnel excavation costs, in terms of operational safety, support materials and construction time. In drill and blast tunnelling, under/over-excavation and rock mass damage arising from excavation phase can be evaluated by means of the elaboration of survey data and geophysical testing or coring, before and after the blast. As far as the quality of the profile is concerned, some indices can be used to define the contour and for the rock mass in the boundary as well. This paper proposes a methodology well applicable to rock tunnelling, and a case study based analysis to correlate the over-excavation and the rock mass conditions is discussed to validate the procedure. Profiles and geological parameters have been processed with automatic code specifically developed for the study. Over-excavation distance and Tunnel Contour Quality Index are evaluated and compared with Q-system values. The results have been discussed, compared with other literature cases and validated for engineering applications.

Assessment of contour profile quality in D&B tunnelling / Costamagna, Elisa; Oggeri, Claudio; Ricardo, Castedo; Pablo, Segarra; Juan, Navarro. - In: TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY. - ISSN 0886-7798. - STAMPA. - 75:May 2018(2018), pp. 67-80. [10.1016/j.tust.2018.02.007]

Assessment of contour profile quality in D&B tunnelling

COSTAMAGNA, ELISA;Claudio Oggeri;
2018

Abstract

Contour profile quality affects tunnel excavation costs, in terms of operational safety, support materials and construction time. In drill and blast tunnelling, under/over-excavation and rock mass damage arising from excavation phase can be evaluated by means of the elaboration of survey data and geophysical testing or coring, before and after the blast. As far as the quality of the profile is concerned, some indices can be used to define the contour and for the rock mass in the boundary as well. This paper proposes a methodology well applicable to rock tunnelling, and a case study based analysis to correlate the over-excavation and the rock mass conditions is discussed to validate the procedure. Profiles and geological parameters have been processed with automatic code specifically developed for the study. Over-excavation distance and Tunnel Contour Quality Index are evaluated and compared with Q-system values. The results have been discussed, compared with other literature cases and validated for engineering applications.
File in questo prodotto:
File Dimensione Formato  
TUST_ 75_2018_oggeri.pdf

non disponibili

Descrizione: Articolo principale e definitivo, sia in versione a stampa che online
Tipologia: 2a Post-print versione editoriale / Version of Record
Licenza: Non Pubblico - Accesso privato/ristretto
Dimensione 2.11 MB
Formato Adobe PDF
2.11 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
ASSESSMENT OF PROFILE QUALITY draft final.pdf

accesso aperto

Tipologia: 1. Preprint / submitted version [pre- review]
Licenza: PUBBLICO - Tutti i diritti riservati
Dimensione 807.08 kB
Formato Adobe PDF
807.08 kB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11583/2691975
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo