Cut-and-Cover Tunneling in the Light Rail
E. Yaşar, A. Kılıç, Y. Erdoğan, and A. Tapınç
Çukurova University, Mining Engineering Department, Balcali-Adana, Turkey
This paper reports applications of engineering techniques of cut-and-cover tunneling and underground stations carried out Adana Light Rail Transit System (Adana Metro). The tunnel was executed using the cut-and-cover construction method. The design included estimates of deformations caused by excavations and other construction activities, evaluation of potential settlements of adjacent buildings and structural evaluation of the response of the buildings to the estimated settlements. Adana Metro project involved complex soil-structure interaction and geometry, and variable ground conditions. The uncertainties in predicting performance in these grounds enhanced the potential for the success of the observational method. The cut and cover tunnel of 5 m. in diameter and 705 m in length was advanced through Quaternary and Tertiary rock unit. Groundwater inflows are expected to be as high as 10-1-10-4 m/s in water-bearing terrace-kalich in this part of tunnel. Anchor support system was used and also intersected piles and impermeable diaphragm wall provided to build in dry site excavation and construction works in 16 m. depth. Ground were characterised in terms of soil classification system. Rock and soil samples were obtained from drilling were tested in rock and soil mechanics laboratory to determine uniaxial compressive strength, deformability parameters, unit weight, atterberg limits, proctor tests, testing of classification of soils.
KEYWORDS: Cut and cover tunnelling, deformation, excavation, weak rock, metro
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