000 03780nas a2200433 a 4500
005 20260817163731.0
008 160129s2013 th uu|m rtt 0| a1eng d
035 _a.b12160799
099 9 _aAIT Thesis no.GE-12-04
100 1 _aTahir, Muhammad Usman
245 1 0 _aAssessment on applicability of sequential tunnel excavation in Bangkok soft ground by means of numerical analysis
260 _aPathum Thani, Thailand :
_bAsian Institute of Technology,
_c2013
300 _a1 online resource (122 p.) :
_bill. +
_e1 online resource
490 1 _aThesis ;
_vno. GE-12-04
500 _aA thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Geotechnical and Earth Resources Engineering, School of Engineering and Technology
502 _aThesis (M. Eng.) - Asian Institute of Technology, 2013
520 _aMechanized tunneling is always feasible and justified with its boring length and in case of short length tunnels or cross cuts between two tunnels or a non circular tunnels required then the excavation method is to be changed from mechanized to the conventional excavation method. A numerical study is performed for assessment of applicability of sequential tunnel excavation in Bangkok subsoil condition. Three schemes of sequential excavation are investigated using the Mohr Coulomb and the Hardening soil model. Three water pressure conditions in the soil layers are defined to explore the effect on tunneling. The undrained effective stress analysis is performed using effective strength and stiffness parameters. The 2D plane strain model is implemented with consideration of the 3D face effect by stress reduction method. Shotcrete lining is considered with two different stiffness values to incorporate approximate effect of shotcrete aging. The results demonstrate that sequential tunnel excavation is not feasible in Bangkok subsoil. Two mechanisms of failure are found first is failure of soil cover above roof and second is the base heave. However, with improved ground it is possible to excavate the tunnel sequentially. Increase in dimension or strength of improved ground results in reduction in lining loads and surface settlement. Hardening soil model results in narrow and deeper surface settlement troughs if compared to the Mohr Coulomb model result. Water pressure variation results in higher bending moment in lining.
650 0 _aTunneling
_xSimulation methods
_zThailand
_zBangkok
650 0 _aExcavation
_xSimulation methods
_zThailand
_zBangkok
700 0 _aNoppadol Phien-Wej,
_eChairperson
700 1 _aBergado, Dennes T.,
_eExamination Committee
700 1 _aPham, Huy Giao,
_eExamination Committee
710 2 _aAsian Development Bank (ADB),
_eScholarship Donor
810 2 _aAsian Institute of Technology.
_tThesis ;
_vno. GE-12-04
856 _3Full-Text
_uhttp://203.159.5.9/ait-thesis/detail.php?q=B03033
907 _a.b12160799
_bmnait
_cz
902 _a240405
998 _b0
_c160129
_dm
_ea
_fz
_g0
962 _a000:001:PDF:b1216079:002391:0:0:0:0:0:0
_tAbstract--AIT Thesis no.GE-12-04
_vn
945 _lmnait
945 _lmnait
945 _lmnarc
942 _c20
942 _c40
909 _aBarcode : 30050120813547
_bCREATED : 2016-01-29
_cRECORD # : i12875636
_dLPATRON : 0
_eLCHKIN : -
_f# RENEWALS : 0
_g# OVERDUE : 0
_hIUSE3 : 1
_iTOT CHKOUT : 0
_jTOT RENEW : 0
909 _aBarcode : 30050120813539
_bCREATED : 2016-01-29
_cRECORD # : i12875648
_dLPATRON : 0
_eLCHKIN : -
_f# RENEWALS : 0
_g# OVERDUE : 0
_hIUSE3 : 0
_iTOT CHKOUT : 0
_jTOT RENEW : 0
909 _aBarcode : 30050120401822
_bCREATED : 2017-09-14
_cRECORD # : i13100464
_dLPATRON : 0
_eLCHKIN : -
_f# RENEWALS : 0
_g# OVERDUE : 0
_hIUSE3 : 0
_iTOT CHKOUT : 0
_jTOT RENEW : 0
999 _c9567
_d9567