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Papers from WTC and ITA conferences have been made available as PDF documents.
List of endorsed conferences
World Tunnelling Congress
Abstract: Underground stations of Jakarta MRT phase 1 project were constructed by top-down cut-and-cover method in alluvial clay and diluvial soil strata. Diaphragm walls for underground stations have a thickness of 1.0 m, and a depth of 21 – 30 m. The monitoring of lateral deflection of D-walls was conducted at all stations for controlling the safety of construction sites and the impact to surrounding...
Abstract: Pure geopolymers are typically made by mixing fly ash with a highly alkaline and caustic solution. Normally, curing at elevated temperatures is needed to gain acceptable strength development. However, most commercial geopolymer cements and concretes are made without the alkaline/caustic solution, but instead made by adding slag or another calcium based material to the mix. Possibly, the...
Abstract: Venda Nova III repowering project is an underground hydropower scheme. Its hydraulic circuit comprises, inter alia, an upstream surge tank, which aims to dissipate hydraulic transients due to turbine and pumping operations. This upstream surge tank consists of a main shaft, an expansion chamber, a lower chamber and two vertical shafts connecting to the headrace tunnel. The two vertical surge...
Abstract: The breakthrough of the TBM at the Røssåga HEPP on 10 December 2015 signaled that the first TBM breakthrough in Norway in more than 20 years was a fact. The Robbins TBM was delivered as an Onsite first time assembly (OFTA) in January 2013 and was ready to bore less than 11 months from when the contract was awarded. During the excavation the TBM encountered extremely hard rock (over 280 MPa),...
Abstract: During deep tunneling or mining infrastructure development, the assumed stress state has significant implications on geomechanical design. Remote measurement of the three dimensional stress state at depth has proven to be a significant challenge and is often assumed from historic tests or the regional tectonic setting. This paper presents a stress estimation methodology using numerical...
Abstract: The maintenance methodology for road tunnel especially over 50 years old become serious issue by a ceiling collapse accident in Sasago highway tunnel occurred in 2012. Following this accident, MLIT (Ministry of Land, Infrastructure, Transportation and Tourism JAPAN) required all administrator the periodic inspections for tunnel lining of road tunnel. A health monitoring for tunnel lining is...
Abstract: During tunnel excavation in soil with TM, either Slurry-Shield or Earth Pressure Balance type, it is of utmost importance assess the pressure to be exerted on the face to ensure the stability of the excavation and control surface deformations. In literature there are reported mostly two-dimensional models that do not consider the spatial nature of the problem. On the other hand, the available...
Abstract: The northern tunnel contract on the Follo Line project, EPC D&B, is excavating the northern part of the Follo Line through Ekeberg Hill. One of the main challenges on the project is the closeness to the already existing infrastructure and caverns. Several of the tunnels on the project will cross or come very close to the existing infrastructure, and there are several challenges related to the...
Abstract: Cracking in tunnel linings is a major cause for reduction in serviceability due to water infiltration and exfiltration, and reinforcement corrosion. In current industry practice, in order to control ground water inflow in lined tunnels, maximum crack width is limited to allowable values in a range of 0.15-0.3 mm specified by the codes, guidelines and recommendations. However, a correlation...
Abstract: The northern tunnel contract on the Follo Line project, EPC D&B, is excavating the last part of the Follo line through Ekebergåsen. One of the main challenges on the project is the closeness to the already existing infrastructure and caverns. Several of the tunnels on the project will cross or come very close to this infrastructure, and there are several challenges related to the low overburden...
Abstract: Pipe umbrella support systems have been used successfully for tunneling in challenging ground conditions since the 1970’s. Due to further developments of the drilling machinery, this pre-support system is used at shallow tunnels in weaker ground conditions on a regular basis. Pipe umbrella pipes are installed stepwise by connecting pipes to each other so the processes “coupling” and...
Abstract: The excavated material represents today a key issue due to environmental constraints and to the claim for possible reuse, so the knowledge of muck characteristics has become a topic. The produced muck presents different properties and behaviour, mainly due to the local geology and to the excavation mode and to the eventual treatment. Then, on the basis of the properties and of the possible...
Abstract: The present paper investigates the effect of the consolidation process on surface settlements developing during on-going tunnel advance or during standstills in water bearing ground. Comparative coupled hydro-mechanical analyses of 3D tunnel models have been performed for the paper. The results illustrate how surface settlements are affected by the advance rate, lining permeability and (for...
Abstract: Tunnels through hard jointed rock are commonly reinforced with a combination of fibre reinforced shotcrete (sprayed concrete), FRS, and rock bolts. The design of such reinforcement is a complex task. First, the interaction between rock bolts, FRS and rock should be considered. Secondly, a natural variation in important parameters such as thickness of the shotcrete, fracture energy, and bond...
Abstract: In this study, the average wear rates of slurry discharge pipes were determined from the thickness of slurry discharge pipe, which was periodically measured at the TBM site in Singapore. The wear rate of slurry pipes for Bukit Timah Granite was obtained. The wear rate of pipes was found to have higher values near the TBM. The wear rates for G(V) grade and mixed zone were 1.5 times higher than...
Abstract: The Lot 1 of Paris metro line 11 consists in 3,6km of tunnels and 4 underground stations in an urbanized environment. The design has been performed by SYSTRA, construction has begun in 2016. The station “Dhuys” consisting of a deep shaft and a 50m long mined tunnel will be realized in the plastic and expansive marly soils of “Ludien” through an instable slope beneath several buildings with a...