Comparisons of Eurocodes design approaches for numerical analysis of shallow tunnels

Paternesi, Alessandra; Schweiger, Helmut; Ruggeri, Paolo; Fruzzetti, Viviene M. E.; Scarpelli, Giuseppe

doi:10.1016/j.tust.2016.12.003

Cited by 11 publications

(9 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…2015 [31]; Ruggeri et at. 2016 [32]; Ruggeri et al 2020 [33]), in the analysis of tunnels along the road (Paternesi et al 2017 [34]), and with more general studies of structurally complex formations (Scarpelli et al 2003 [35]; Ruggeri et al 2016 [36]; Ferretti et al 2019 [37]), aims at addressing possible design strategies to reduce the risk of inducing slope instabilities, dangerous releases of soil masses, and excessive stresses in the retaining structures. Because of the main structural features of the Blue Clay formation, the most effective design strategies could be found only on the basis of a detailed geological model, on the top of which geotechnical models could be implemented with due consideration of the pattern of existing discontinuities; in most cases, design solutions were sought with the aim of reducing stress release in the zone of influence of excavations.…”

Section: The Dg21 and Dg22 Maxi Lotsmentioning

confidence: 99%

Design Strategies to Mitigate Slope Instabilities in Structurally Complex Formations

2020

Self Cite

View full text Add to dashboard Cite

Stiff jointed clays (SJC) belong to so-called structurally complex formations in which the macroscale features of the deposit, that is the pattern of discontinuities affecting the soil mass, influence its response at the scale of engineering works. Such peculiar response was largely recognized during the excavation works carried out for the construction of two new road segments in southern Italy, where several structurally conditioned instability processes were triggered during excavation works. These phenomena mainly involved the Plio-Pleistocene marine clayey formation outcropping along the East coast of the Calabria region, where it constitutes most of the hills interested by construction works. Under a geotechnical perspective, the SJC-formation exhibits good mechanical characteristics at the scale of samples but, if considered as a whole, its behaviour is governed by the presence of discontinuities along which strength is typically at residual. Building on the author’s experience of some exemplary failure events, this paper aims at defining possible design strategies to minimize the risk of adverse and unexpected instability phenomena during construction in structurally complex formations. Design strategies oriented at reducing and possibly avoiding stress releases in the zone of influence were found to be most effective at preventing failures or restoring safety after the occurrence of a failure event.

show abstract

Section: The Dg21 and Dg22 Maxi Lotsmentioning

confidence: 99%

Design Strategies to Mitigate Slope Instabilities in Structurally Complex Formations

2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Generally, the urban shallow tunnel construction in silty soil is an urgent problem to be solved in tunnel construction in coastal areas. Many studies on tunnel construction in silty soil have proved the difficulty and complexity of the problem [23,24]. However, there are few studies on urban shallow tunnel construction by STM.…”

Section: Discussionmentioning

confidence: 99%

“…Fang et al [19], Yang and Huang [20], Ocak [21], and Bian et al [22] used field tests and theoretical calculation to study large deformation and rock mass pressure in soft rock of shallow tunnels in soft soil. Additionally, Paternesi et al [23] and Cao et al [24] employed finite element analysis and field measurement to analyze surface settlement of shallow tunnelling method (STM) for subway station in soft soil. Fetzer et al [25], Nazari et al [26], and Bryk [27] carried out laboratory tests and microscopic photographs to analyze the granular characteristics and permeability of silty soil.…”

Section: Introductionmentioning

confidence: 99%

Displacement Characteristics of an Urban Tunnel in Silty Soil by the Shallow Tunnelling Method

Zhang

Qiu

et al. 2020

Advances in Civil Engineering

View full text Add to dashboard Cite

The urban shallow tunnelling process in silty soil is easy to cause large displacement of surface and tunnel. Obviously, if the strata and the tunnel face are not treated by reasonable reinforcement method, instability and collapse phenomenon will be encountered during the tunnel excavation. There are a series of studies on construction methods of shallow tunnels, but these methods have limitations in silty soil. In this study, a comprehensive construction plan of the urban shallow tunnel in silty soil was proposed and applied to a case study in Fuzhou, Fujian Province in South China. The in situ monitoring tests and numerical simulation were employed to address displacement characteristics of surface and tunnel. Results indicated that the urban shallow tunnelling process could achieve good effect by dewatering of silty soil, reinforcing surface by vertical jet grouting piles, and advanced small pipes and circumferential grouting in the tunnel face; surface settlement during dewatering process accounted for about 30% of total surface settlement in silty soil; the excavation of the top heading, the middle, and lower benches had great effect on displacement of surface and tunnel for three-bench seven-step excavation method in silty soil; surface settlement troughs in silty soil were deeper and wider; lock-feet bolts had good effect on restricting horizontal convergence; and ratio of total crown settlement and total horizontal convergence was in range of 1.43∼1.59 when b/h was 0.88 in silty soil. The construction plan proposed in this paper is helpful for further study of shallow tunnel tunnelling process in silty soil.

show abstract

“…Zum letzten Punkt der Aufzählung muss an dieser Stelle jedoch betont werden, dass durchaus noch Diskussionsbedarf besteht, in welcher Form dies geschehen soll. Ein Vorschlag der Realisierung für oberflächennahe Tunnel ist in aufgezeigt und könnte auch für andere Problemstellungen adaptiert werden.…”

Section: Finite‐elemente‐methodenunclassified

Zur Beurteilung der Standsicherheit von Böschungen mit unterschiedlichen Verfahren

Schweiger

Tschuchnigg

2017

Geotechnik

Self Cite

View full text Add to dashboard Cite

Zur Beurteilung der Standsicherheit und damit von Sicherheitsfaktoren von Böschungen, Hängen und Dämmen werden in der Praxis vorwiegend Grenzgleichgewichtsbetrachtungen, meist mittels Lamellenverfahren, eingesetzt. Neuere Untersuchungen zeigen jedoch, dass diese Verfahren in manchen Fällen Ergebnisse liefern, die deutlich auf der unsicheren Seite liegen können. Als Alternative bieten sich numerische Verfahren wie die Finite‐Elemente‐Methode an, wobei zwei unterschiedliche Formulierungen zum Einsatz kommen können. Erstens Formulierungen, die auf Verschiebungsansätzen beruhen, und zweitens Formulierungen, die die Schrankentheoreme der Plastizitätstheorie als Grundlage haben. In diesem Beitrag wird gezeigt, dass diese numerischen Verfahren den Lamellenverfahren hinsichtlich Aussagekraft generell überlegen sind, wenn auch ein etwas höherer Berechnungsaufwand in Kauf zu nehmen ist.

show abstract

Comparisons of Eurocodes design approaches for numerical analysis of shallow tunnels

Cited by 11 publications

References 9 publications

Design Strategies to Mitigate Slope Instabilities in Structurally Complex Formations

Design Strategies to Mitigate Slope Instabilities in Structurally Complex Formations

Displacement Characteristics of an Urban Tunnel in Silty Soil by the Shallow Tunnelling Method

Zur Beurteilung der Standsicherheit von Böschungen mit unterschiedlichen Verfahren

Contact Info

Product

Resources

About