A Numerical Investigation of Segmental Lining Joints Interactions in Tunnels-Qomrud Water Conveyance Tunnel
Abstract: A comprehensive
analysis of segmental lining joints can assist to guarantee a safe construction
during tunnelling and serviceably stages.
This paper has thoroughly investigated the interaction mechanism of
precast concrete lining joints in tunnels. The Universal Distinct Element Code
(UDEC), a two-dimensional numerical program based on the distinct element
method (DEM) for discontinuum modelling, was implemented to simulated a typical
segmental lining model consisting of six segment rings. In the analyses, the
typical segmental lining design parameters of Qomrud water conveyance tunnel,
aimed to transfer 100 million cu. m. water from the origins of Dez River to
central Iranian desert, were employed to fulfil the purpose of the research. In the conducted analyses, the worst-case
scenario of the loading faced during the boring of Qomrud tunnel was
considered. This was highly associated with the existence of the crushed zone
dipping at 75 degree at the location of the key segment. The worst scenario based on the condition
that concerns the crushed zone intersect segmental lining at the location of
key segment has been taken into consideration. In this study, the load acting
on the joints of the segments includes the gravity load from the tunnel
overburden and the crushed zone stratum force that intersects tunnel with 75
slopes at the location of the key segment, the gravity force of the segments
and the earth pressure. The numerical investigation has been used for the
different coefficients of stress concentration of 0.5, 1, 1.5, 2 and also
different geological conditions of the saturated crushed zone under critical
scenario.
Keywords: The Universal
Distinct Element Code (UDEC); DEM Method; Contact Problem; Longtidunal Joint;
Interface; Key Segment
Author: Mohammad Hossein
Ahmadi, Ali Mortazavi, Seyed Morteza Davarpanah, Hamid Zarei
Journal Code: jptsipilgg160041
