2023年全國碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
已閱讀1頁,還剩8頁未讀 繼續(xù)免費閱讀

下載本文檔

版權(quán)說明:本文檔由用戶提供并上傳,收益歸屬內(nèi)容提供方,若內(nèi)容存在侵權(quán),請進行舉報或認領(lǐng)

文檔簡介

1、Ground–liner interaction in rock tunnelingMoorak Son a,*, Edward J. Cording ba Korean Intellectual Property Office, Construction Technology Exam., Government Complex, Daejeon Building 4, Dunsan-dong, Seo-gu, Daejeon, Sou

2、th Korea b Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 205 N. Mathews Avenue MC-250, Urbana, IL 61801, United StatesReceived 20 March 2005; received in revised form 15 A

3、ugust 2005; accepted 20 March 2006 Available online 2 May 2006AbstractTunnel constructions are gradually increasing because of the development and upgrade of infrastructures such as highway, subway, railway, and many oth

4、er facilities. Most of tunnels are excavated either by using drilling and blasting or by using tunnel excavation machines such as TBM (tunneling boring machine) or Shield. NATM (new Austrian tunneling method) is one of m

5、ost frequently used tunneling methods and it uses drilling and blasting to excavate a tunnel in rock. While tunnel excavation using TBM or Shield machines produces quite a regular and smooth tunnel excavation surface, th

6、e tunnel excavation using drilling and blasting results in a very irreg- ular and rough excavation surface. The stress behavior in a shotcrete tunnel liner installed along the excavation surface is very dependent on the

7、surface status and tunnel engineer should consider the surface condition for the design of a shotcrete tunnel liner. Numerical analyses are conducted to investigate the effect of the irregularity of tunnel excavation sur

8、face on the response of the shot- crete tunnel liner. For the investigations, the controlled parameters include the irregularity of the excavation surface, the stiffness of the surrounding ground, and the coefficient of

9、earth pressure at rest. The investigations show that the response of a shotcrete tunnel liner is highly dependent on the parameters and for the same earth pressure condition the effect is more evident when the irregulari

10、ty is more severe and the surrounding ground is less stiff. ? 2006 Elsevier Ltd. All rights reserved.Keywords: Rock tunnel; Excavation surface irregularity; Shotcrete liner; Ground–liner interaction; Flexibility1. Introd

11、uctionTunnel is a main underground structure and is widely used for transportation transfer, water passage, and other purposes such as electricity or communication cable installation. With the development and upgrade of

12、infra- structures, tunnel construction is increasing all over the world and tunnel engineer is more aware of the impor- tance of the safety and economics of tunnel construction. In relation to tunnel construction, Peck (

13、1969) stated three issues, which are first, maintaining stability and safety during construction, second, minimizing unfavor-able impact on 3rd parties, and finally performing intended function over the life of a project

14、. Among the issues, the first issue is directly related to the appropriate design of tunnel support system. In rock tunneling, the tunnel excavation conducted either by using drilling and blasting or by using tunnel exca

15、vation machines such as TBM or Shield. NATM (new Austrian tunneling method), which is widely used for a tunnel construction, uses the drilling and blasting method to excavate a tunnel in rock and a shotcrete liner and ro

16、ck bolts are used as a main support system. The tun- nel excavation using drilling and blasting results in a rela- tively irregular tunnel excavation surface, compared with tunnel excavation machines using TBM or Shield.

17、 The level of the irregularity depends on blasting method, rock stiff- ness, rock joint characteristic, scaling, and workmanship.0886-7798/$ - see front matter ? 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.tust

18、.2006.03.002* Corresponding author. Tel.: +82 11 9831 6940; fax: +82 42 472 3519. E-mail addresses: moorakson@empal.com (M. Son), ecording@uiuc.edu (E.J. Cording).www.elsevier.com/locate/tustTunnelling and Underground Sp

19、ace Technology 22 (2007) 1–9Tunnelling and Underground Space Technologyincorporating TrenchlessTechnology ResearchFor the uniform external pressure, P, the diametral strain of the circular tunnel liner (Fig. 2b) is given

20、 byDDD ¼ PRElt ð8Þand the extensional stiffness of the liner in plane strain is defined by as follows:PDD=D ¼ EltRð1 ? t2 l Þ ð9Þwhere El is the elastic modulus of the liner and R

21、and t are, respectively, the radius and the thickness of the liner. The compressibility ratio (C) is obtained by dividing the exten- sional stiffness of ground by that of the liner and is defined as follows:C ¼E 

22、40;1þtÞð1?2tÞElt Rð1?t2 l Þ ð10ÞA tunnel liner should be designed safe and stable for the thrust and moment induced by the external load. Because of the interaction between the gro

23、und and the liner, the thrust and moment in the liner are affected by the flexibility and compressibility ratios as Burns and Richard (1964) have shown. For a given condition, the measure of moment and thrust in the line

24、r can be theoretically obtained as follows:MomentðMÞ ¼ PR22 ð1 þ KoÞ ð1 ? 2tÞC6F? ?½1 ? Ln??þ 0:5ð1 ? KoÞ½1 ? J n ? 2N n? cos 2h?ð11ÞThrustð

25、TÞ ¼ PR22 ð1 þ KoÞ½1 ? Ln f ?þð1 ? KoÞ½1 þ J n? cos 2hg ð12Þwhere Ko is the earth pressure coefficient at rest, h is the an- gle measured in counterclockwi

26、se from horizontal plane, F is the flexibility ratio and C is the compressibility ratio.Ln ¼ ð1 ? 2tÞðC ? 1Þ1 þ ð1 ? 2tÞC ð13ÞJ n ¼ ½ð1 ? 2tÞð1 ?

27、 CÞ?F ? 0:5ð1 ? 2tÞ2C þ 2½ð3 ? 2tÞ þ ð1 ? 2tÞC?F þ 0:5ð5 ? 6tÞð1 ? 2tÞC þ ð6 ? 8tÞð14ÞN n ¼ ½1 þ ð1

28、? 2tÞC?F ? 0:5ð1 ? 2tÞC ? 2½ð3 ? 2tÞ þ ð1 ? 2tÞC?F þ 0:5ð5 ? 6tÞð1 ? 2tÞC þ ð6 ? 8tÞð15ÞThe moment and thrust that are theore

29、tically deter- mined are based on the assumption that the liner has a uni- form thickness along the tunnel perimeter and there is no slippage at the contact between the ground and the liner. The theoretical values of the

30、 moment and thrust at the tun- nel crown and springline are plotted and compared with the results of numerical analyses under various conditions in the following section.3. Numerical analysisNumerical analyses are run to

31、 investigate the response of the liner in rock tunneling. As mentioned previously, rock tunneling with drilling and blasting induces a tunnel excavation surface irregular and rough. The irregularity of the excavation sur

32、face may result in the thrust and moment increase in the liner installed along the tunnel excavation perimeter due to the stress concentration. How- ever, the theoretical relationship for the ground–liner inter- action i

33、s based on the assumption that the tunnel excavation surface is smooth enough with no irregularity and the liner thickness is uniform along the tunnel perimeter. In rock tunneling excavated with drilling and blasting, it

34、 is difficult to make the tunnel excavation surface com- pletely smooth, though it is possible to reduce the level of irregularity. Accordingly, it is quite important to investi- gate the thrust and moment change in a sh

35、otcrete tunnel liner due to the irregularity and to provide some reasonable concepts for designing and installing a shotcrete tunnel liner for a tunnel in rock, which is excavated with drilling and blasting. Numerical an

36、alyses are performed with the 2-D Univer- sal Distinct Element Code (UDEC 3.1, 2000). The advan- tages of the numerical analysis are that many different conditions can easily be considered under limited time, cost, and s

37、pace, and reproducible analyses are possible. These characteristics enable the effects of various parame- ters on the responses of a shotcrete tunnel liner installed along the irregular tunnel excavation surface to be in

38、vestigated. A tunnel is assumed to have a circular shape with the diameter of 10m and to be constructed at the depth of 30 m below the ground surface (Fig. 3). Considering the symmetric condition of the tunnel, a quarter

39、 portion of the tunnel is used for the numerical tests (Fig. 4a–4d). The boundary condition for the ground and liner was roller supports at the left vertical and bottom horizontal bound- aries and the ground stress was a

溫馨提示

  • 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請下載最新的WinRAR軟件解壓。
  • 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
  • 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁內(nèi)容里面會有圖紙預(yù)覽,若沒有圖紙預(yù)覽就沒有圖紙。
  • 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
  • 5. 眾賞文庫僅提供信息存儲空間,僅對用戶上傳內(nèi)容的表現(xiàn)方式做保護處理,對用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯,并不能對任何下載內(nèi)容負責。
  • 6. 下載文件中如有侵權(quán)或不適當內(nèi)容,請與我們聯(lián)系,我們立即糾正。
  • 7. 本站不保證下載資源的準確性、安全性和完整性, 同時也不承擔用戶因使用這些下載資源對自己和他人造成任何形式的傷害或損失。

最新文檔

評論

0/150

提交評論