Search & filter
Search & filter
Papers from WTC and ITA conferences have been made available as PDF documents.
List of endorsed conferences
World Tunnelling Congress
Abstract: High Speed Two (HS2) is a new £56 billion ($67 billion) high speed (alignment for 400 km/hr) railway which will form a “spine” of a reshaped rail network providing an engine for growth and connecting eight out of the top ten regions within Great Britain. There are about 60km of twin bore (11 tunnels) and 11km of (17 tunnels) cut-and-cover tunnels along the HS2 route. This paper describes the...
Abstract: The tunnels of the Milan Metro 5 are located at a short distance from the rails of Domodossola railway station because it was necessary to maintain the elevation of the tracks and to avoid that the tunnel section would be totally submerged by the water table. The crown excavation reinforcing, realized by means of double overlapping sub horizontal jet grouting columns and forepoling, resulted...
Abstract: The Brusnice tunnel is an important part of the Prague City Ring Road. The tunnel was excavated using NATM method (mostly in shales and deluvial sediments). The geotechnical monitoring was carried out during construction and its results give a good opportunity to perform a back analysis. After a short introduction, the authors briefly describe the selected cross-section, the geological...
Abstract: The upgrade of the RBS railway station in Bern requires the excavation of two large station caverns with two cross-passages and four staircases. The new underground structures are mainly in soft rock and partially below the ground water table. Along with the minor overburden of the station caverns, the underground excavations are demanding because of the execution under operation of the...
Abstract: This paper focuses on the environmental impact of soil conditioning agents used in the mechanized excavation of tunnels. The effects of the chemical composition, dosage and injection mode of the different additives, as well as the effects of soil characteristics and the influence of the aerobic and anoxic environment on chemical biodegradation, through tailored laboratory tests were...
Abstract: Large shotcrete excavations in cohesionless soils require extensive measures, so that the excavation can be carried out in a safe way. Especially underneath existing buildings, the excavations should be carried out with minimal settlements. To be able to guarantee an excavation with the least possible settlement occurrence, various production methods exist. In this paper the results of...
Abstract: Up-close visual inspections have been mandatory and hammering tests were done as necessary in periodical inspections for all road tunnels in Japan from 2014. Information obtained by the inspections should be accurately evaluated in order to diagnose soundness of the tunnels and take proper countermeasures correctly. Defect and deformation mechanisms of the permanent lining of mountain...
Abstract: There are more than 10,000 road tunnels in Japan, and every year, more and more tunnels reach the end of their service lifetimes. These tunnels include some in which their lining concrete has been deformed by external force so that they require reinforcement measures. The authors have developed a reinforcement method that can guarantee adequate load-bearing capacity by using precast concrete...
Abstract: Preventing concrete spalling is very important in tunnel maintenance because spalling in railway tunnels may causes a direct safety hazard to train operations. This paper deals with the applicability of sprayed polyurea as the spalling prevention method of tunnel lining concrete. The model test and trial construction have been carried out. In the model test, vertical displacement was applied at...
Abstract: During ongoing underground construction of Line 8 of 3 phase of the metro expansion in Delhi, the Delhi Metro Corporation (DMRC) had good collective experience of tunneling in urban environment and building underground stations. Many key decisions were made during initial planning stage to benefit the project. New challenges had to be faced everyday, which are unique to underground tunneling in...
Abstract: The Ring Rail Line is an important circular route of the Helsinki Metropolitan Area. It is an ur ban rail line and a rail connection to the Helsinki-Vantaa airport. During excavation works under the Helsinki Vantaa airport liquid fluid was noticed leaking into the tunnel, which by odour is related to anaerobic process es. The fluids contain nutrients that enable the growth of microbes. The...
Abstract: Stability assessment of an underground powerhouse cavern is a challenging issue, especially in the Himalayan region where rock mass is heavily influenced with active tectonic movement. This article is concerned with the stability assessment of a large underground opening inside the valley toe, where the rock cover varies between 45m (minimum) and 48m (maximum). The planned powerhouse cavern has...
Abstract: Duct bank is a widely distributed and shallow buried underground structure. It can easily affected by engineering construction activities. In order to meet the demand of early warning of cracking of concrete and health monitoring of structure. The deformation characteristics of the duct bank was simulated using a three-dimensional finite element method to measure its structural performance....
Abstract: Road 6 is one of the largest infrastructure projects undertaken in Israel and is carried out mainly by private sector in form of concessionaire. Three tunnels named Yokneam, Rehasim and Ibtin are actually under construction. Each tunnel is arranged as a system of twin tunnels connected by transverse cross passages. Tunnels are excavated within a series of sedimentary rock mass formations range...
Abstract: Subsea tunnels are highly vulnerable to seawater intrusion caused by high water pressure during construction. The artificial ground freezing (AGF) will be a promising alternative to conventional reinforcement methods. Use of brine as a refrigerant is disadvantageous because of its longer freezing time due to the high boiling point. On the other hand, liquid nitrogen, which can freeze saturated...
Abstract: The form of shield tunnel cross sections has gone through several phases, from rectangular to circular, and then to non-circular. To study the key design and construction techniques of quasi rectangular shield tunnels, Chinese engineers have chosen to build the world’s first quasi rectangular shied tunnel in the construction of one interval of Ningbo Metro Line 3, taking into consideration both...