A parametric study on three dimensional modeling of parallel tunnel interactions

Download
2010
Karademir, Salahaddin Miraç
A parametric study is performed to investigate the parallel tunnel interaction. Three dimensional finite element analyses were performed to determine the effects of soil stiffness, pillar width and advancement level of the second tunnel on the behaviour of displacement, bending moment and shear force of the previously constructed tunnel. In the analysis PLAXIS 3D Tunnel geotechnical finite element package was used. This program allows the user to define the actual construction stages of a NATM tunnel construction. In the analysis, construction stages are defined in such a way that firstly one of the tunnels is constructed and the construction of the second tunnel starts after the construction of the first tunnel. The mid-length section of the first tunnel is investigated in six different locations and at seven different advancement levels in terms of displacement, bending moment and shear forces. It is found that, displacement and bending moment behaviour are more related with soil stiffness and pillar width than the behaviour of shear forces. While the level of advancement of the second tunnel causes different type of responses on the shear force behaviour, level of advancement does not affect the type of behaviour of displacements and bending moments. Another finding of the research is that pillar width has an evident influence on the behaviour of displacements and bending moment than the soil stiffness. It is also found that the interaction effect may be eliminated by increasing the pillar width equal or larger than an approximate value of 2.5 – 3.0 D (diameter) for an average soil stiffness value.

Suggestions

A laboratory study of anisotropy in engineering properties of Ankara clay
İspir, Mustafa Erdem; Ergun, Mehmet Ufuk; Department of Civil Engineering (2011)
Anisotropy in engineering properties of soils occurs due to the depositional process forming the soil fabric and/or different directional stresses in soil history. This study investigates the anisotropy in undrained shear strength and drained compressibility of preconsolidated, stiff and fissured Ankara Clay. The compressibility behavior is determined using standard oedometer testing while the shear strength anisotropy is investigated through large diameter unconsolidated-undrained triaxial testing on undis...
A PARYLENE BONDING BASED FABRICATION METHOD FOR GRAVIMETRIC RESONANT BASED MASS SENSORS
Gokce, Furkan; Aydın, Eren; Kangül, Mustafa; Toral, Taylan B.; Zorlu, Ozge; Sardan-Sukas, Ozlem; Külah, Haluk (2017-06-22)
In this study, a fabrication method utilizing parylene bonding for gravimetric resonant based mass sensors is presented. First, parylene bonding was experimentally tested and compared with the literature. Average shear strength was measured as 16.3 MPa (sigma=3MPa). Then, resonators located on top of a microchannel for real-time detection were fabricated using the presented method. Simulations and experiments verify proper operation of the fabricated resonators, and the applicability of the method for fabri...
A parallel gas-kinetic Bhatnagar-Gross-Krook method for the solution of viscous flows on two-dimensional hybrid grids
Ilgaz, M.; Tuncer, İsmail Hakkı (Informa UK Limited, 2009-01-01)
In this study, a parallel implementation of gas-kinetic Bhatnagar-Gross-Krook method on two-dimensional hybrid grids is presented. Boundary layer regions in wall bounded viscous flows are discretised with quadrilateral grid cells stretched in the direction normal to the solid surface while the rest of the flow domain is discretised by triangular cells. The parallel solution algorithm on hybrid grids is based on the domain decomposition using METIS, a graph partitioning software. The flow solutions obtained ...
Monitoring the Microstructural Evolution in Spheroidized Steels by Magnetic Barkhausen Noise Measurements
DAVUT, Kemal; Gür, Cemil Hakan (Springer Science and Business Media LLC, 2010-12-01)
The aim of this study is to monitor nondestructively the degree of spheroidization in steels by Magnetic Barkhausen Noise (MBN) method. Various series of specimens consisting of either lamellar pearlite or partially/completely spheroidized carbides were produced from AISI 1060 steel by appropriate heat treatments. All specimens were characterized by metallographic examinations, hardness and MBN measurements. The results show that MBN signals are very sensitive to the variations in the microstructure caused ...
A LINEAR MATHEMATICAL-MODEL FOR THE SEISMIC INPLANE BEHAVIOR OF BRICK MASONRY WALLS .1. THEORETICAL CONSIDERATIONS
Mengi, Yalçın; Sucuoğlu, Haluk; McNiven, Hugh (Wiley, 1984-01-01)
In this study two mathematical models are presented for the linear dynamic behaviour of masonry walls. The study is completed in three stages: experimental observations, selection of a mathematical model and the determination of model parameters through optimization analysis. In the present paper (Part 1) the theoretical analysis used in the development of the mathematical models is presented. Part 2 is devoted to the optimization analysis. Evaluation of the experimental data, which is described in detail ...
Citation Formats
S. M. Karademir, “A parametric study on three dimensional modeling of parallel tunnel interactions,” M.S. - Master of Science, Middle East Technical University, 2010.