土木工程 建筑外文翻譯 --基于盾構(gòu)法的istanbul地鐵施工引起的地面沉降預(yù)測(cè)（英文）

1、ORIGINAL ARTICLESurface settlement predictions for Istanbul Metro tunnels excavated by EPB-TBMS. G. Ercelebi ? H. Copur ? I. OcakReceived: 13 July 2009 / Accepted: 15 March 2010 / Published online: 27 March 2010 ? Spring

2、er-Verlag 2010Abstract In this study, short-term surface settlements are predicted for twin tunnels, which are to be excavated in the chainage of 0 ? 850 to 0 ? 900 m between the Esenler and Kirazl? stations of the Istan

3、bul Metro line, which is 4 km in length. The total length of the excavation line is 21.2 km between Esenler and Basaksehir. Tunnels are excavated by employing two earth pressure balance (EPB) tunnel boring machines (TBMs

4、) that have twin tubes of 6.5 m diameter and with 14 m distance from center to center. The TBM in the right tube follows about 100 m behind the other tube. Segmental lining of 1.4 m length is currently employed as the fi

5、nal support. Settlement pre- dictions are performed with finite element method by using Plaxis finite element program. Excavation, ground support and face support steps in FEM analyses are simulated as applied in the fie

6、ld. Predictions are performed for a typical geological zone, which is considered as critical in terms of surface settlement. Geology in the study area is composed of fill, very stiff clay, dense sand, very dense sand and

7、 hard clay, respectively, starting from the surface. In addition to finite element modeling, the surface settlements are also predicted by using semi-theoretical (semi-empirical) and analytical methods. The results indic

8、ate that the FE model predicts well the short-term surface settlements for a given volume loss value. The results of semi-theoretical and analytical methods are found to be in good agreement with the FE model. The result

9、s of predictions are compared andverified by field measurements. It is suggested that grouting of the excavation void should be performed as fast as possible after excavation of a section as a precaution against surface

10、settlements during excavation. Face pres- sure of the TBMs should be closely monitored and adjusted for different zones.Keywords Surface settlement prediction ? Finite element method ? Analytical method ? Semi-theoretica

11、l method ? EPB-TBM tunneling ? Istanbul MetroIntroductionIncreasing demand on infrastructures increases attention to shallow soft ground tunneling methods in urbanized areas. Many surface and sub-surface structures make

12、under- ground construction works very delicate due to the influ- ence of ground deformation, which should be definitely limited/controlled to acceptable levels. Independent of the excavation method, the short- and long-t

13、erm surface and sub-surface ground deformations should be predicted and remedial precautions against any damage to existing structures planned prior to construction. Tunneling cost substantially increases due to damages

14、to structures resulting from surface settlements, which are above toler- able limits (Bilgin et al. 2009). Basic parameters affecting the ground deformations are ground conditions, technical/environmental parameters and

15、tunneling or construction methods (O’Reilly and New 1982; Arioglu 1992; Karakus and Fowell 2003; Tan and Ranjit 2003; Minguez et al. 2005; Ellis 2005; Suwansawat and Einstein 2006). A thorough study of the ground by site

16、 investigations should be performed to find out the physicalS. G. Ercelebi (&) ? H. Copur Mining Engineering Department, Istanbul Technical University, Maslak, 34469 Istanbul, Turkey e-mail: ercelebi@itu.edu.trI. Oca

17、k Rail Transportation Department (IETT), Istanbul Metropolitan Municipality, Istanbul, Turkey123Environ Earth Sci (2011) 62:357–365DOI 10.1007/s12665-010-0530-6300 kPa of pressure through the grout cannels in the trailin

18、g shield. This method of construction has been pro- ven to minimize the surface settlements.The study area includes the twin tunnels of the chai- nage between 0 ? 850 and 0 ? 900 m, between Esenler and Kirazl? stations.

19、Gungoren Formation of the Miosen age is found in the study area. Laboratory and in situ tests are applied to define the geotechnical features of the formations that the tunnels pass through. The name, thickness and some

20、of the geotechnical properties of the layers are summarized in Table 2 (Ayson 2005). Fill layer of 2.5-m thick consists of sand, clay, gravel and some pieces of masonry. The very stiff clay layer of 4 m is grayish green

21、in color, consisting of gravel and sand. The dense sand layer of 5 m is brown at the upper levels and greenish yellow at the lower levels, consisting of clay, silt and mica. Dense sand of 3 m is greenish yellow and consi

22、sts of mica. The base layer of the tunnel is hard clay, which is dark green, consisting of shell. The underground water table starts at 4.5 m below the surface. The tunnel axis is 14.5 m below the surface, close to the c

23、ontact between very dense sand and hard clay. This depth isMarmara SeaAksarayOtogarBa ak ehir0 km 5 kmEuropean SideAnatolia SideBosphorusBak?rkoy IDOHalkal?Olimpiyat köyüGüney sanayiAtatürk AirportG

24、olden HornKirazl? 10+000 0+500 1+000 1+500 2+000 2+500 3+000 3+500 4+000

25、 4+500 5+000 Viad. At Grade R.W Bored Tunnel Bored Tunnel Bored Tunnel

26、 Bored Tunnel 10 20 30 40 50 60 70 80 Cut& CoverCut& CoverCut& CoverCut& Cover Structure Type Kilometer Fill Clay Sand Trakya formation Metro line 0 m 250 m F

27、ig. 1 Main route and geological section of Esenler and Basaksehir Metro Line (Ocak 2009)Table 1 Some of the technical features of the EPB-TBMsHerrenknecht LovatExcavation diameter 6.500 m 6.564 mShield outside diameter 6

28、.45 m 6.52 mTBM length 7.68 m 9.30 mBackup length 80 m 65 mTotal weight 578 t 534 tMaximum cutter head RPM 0–2.5 0–6.0Total installed power 963 kW 1,622 kWCutter head type Mixed ground Mixed groundCutter head power 630 k