Overcoming Squeezing in the Yacambú-Quibor Tunnel,Venezuela   总被引：2，自引：2，他引：0  

E. Hoek  R. Guevara 《Rock Mechanics and Rock Engineering》2009,42(2):389-418

Summary  The 5 m diameter 23.3 km long Yacambú-Quibor tunnel is designed to carry water through the Andes from the Yacambú dam in the wet tropical Orinoco basin to the semi-arid but fertile Quibor basin in western Venezuela. The tunnel is excavated in silicified and graphitic phyllites at depths of up to 1270 m below surface and extreme squeezing problems have been encountered. Construction involved 8 contracts extending over 32 years with breakthrough being achieved in July 2008. Several excavation methods and various lining designs were used over the years until the adoption of yielding support permitted the Owner and the Contractor to agree that only a circular section would be used and emphasis was placed on developing a routine construction procedure, irrespective of the rock conditions encountered at the face. This paper describes some of the rock engineering issues that were faced during the construction of this tunnel. Correspondence: E. Hoek, Consulting Engineer, Vancouver, Canada  相似文献   

冰（雪）晶生长微物理过程的风洞实验研究     

龚乃虎  陶树旺 《高原气象》1996,15(2):250-257

该文简要介绍了（１）风洞实验研究的科学意义及应用前景；（２）冰（雪）晶增长微物理实验的研究的概况；（３）新研制的冰（雪）晶增长小型垂直过冷云风洞及其测试系统；（４）主要实验研究结果，包括风洞实验模拟出的冰（雪）晶，含水量对冰（雪）晶增长的影响，风洞中冰（雪）晶的运动方式，初始晶胚特性及运用实验结果指导象灾害的预测及防治。  相似文献   

Simple evaluation of the effect of seismic isolation by covering a tunnel with a thin flexible material     

Kazuo Konagai  Dae-Sang Kim   《Soil Dynamics and Earthquake Engineering》2001,21(4)

Long-term earthquake observations at different tunnel sites within a variety of alluvial soil deposits have clearly demonstrated that a tunnel, which exhibits rather flexible nature within its surrounding soil, follows closely the motion of the soil mass during an earthquake. Therefore, coating a tunnel with a soft material will be a possible measure for minimizing damage to tunnels. This paper provides a clear perspective on the feasibility of this measure by using simple solutions to idealized problems.  相似文献   

超前地质预报在隧道工程中的应用   总被引：11，自引：1，他引：11  

吴江滨 《工程地质学报》2003,11(2):162-168

前方地质情况不明常常给隧道施工带来危险, 为解决这一问题, 超前地质预报工作应运而生。通过长梁山隧道的工程实践, 进一步证明了开展超前地质工作的重要性。  相似文献   

Observations of Boundary-Layer Wind-Tunnel Flow over Isolated Ridges of Varying Steepness and Roughness   总被引：2，自引：2，他引：2  

Keith W. Ayotte  Dale E. Hughes 《Boundary-Layer Meteorology》2004,112(3):525-556

Boundary-layer wind-tunnel flow is measured over isolated ridges of varyingsteepness and roughness. The steepness/roughness parameter space is chosento produce flows that range from fully attached to strongly separated. Measurementsshow that maximum speedup at the hill crest is significantly lower than predictedby linear theory and that recovery in the lee of the hill is much slower for stronglyseparated flow over steep terrain. The measurements also show that behaviour ofthe mean and turbulent components of the flow on the downwind side of the ridgeis fundamentally different between separated and non-separated flows. This suggeststhe dominance of much increased turbulence time and length scales in the lee of thehill in association with a production mechanism that scales with the hill length ratherthan the proximity to the surface as on the windward side of the hill crest.  相似文献   

An example of landslide-inflicted damage to tunnel in the 2004 Mid-Niigata Prefecture earthquake     

Kazuo Konagai  Muneyoshi Numada  Athanasios Zafeirakos  Jörgen Johansson  Amir Sadr  Toshihiko Katagiri 《Landslides》2005,2(2):159-163

A large number of landslides induced by the 2004 Mid Niigata Prefecture earthquake resulted in the closure of 233 segments of national and prefectural routes in Higashiyama mountain district, and 61 localities were completely isolated. Since railway and road facilities follow closely the motion of soils, damage to these facilities has to be discussed in terms of soil deformations that they experienced. The example of Kizawa tunnel shows that even relatively small soil deformations can be large enough to cause serious cracking of tunnel lining.  相似文献   

深埋岩溶隧道涌水最大水头压力评估     

徐则民  黄润秋  范柱国  吴培关 《地球科学进展》2004,(Z1)

深埋隧道涌水最大水头压力的预测具有重要的实际意义。提出了充水水源为地下暗河、充水通道为管状、板状及裂隙网络3种条件下深埋岩溶隧道涌水水头压力的近似计算公式。  相似文献   

地铁隧道限界测量中横断面确定的研究     

吉文来  高俊强 《现代测绘》2004,27(6):22-23

盾构法施工构成隧道的中线测量和限界(横断面)测量是铺轨的前期必要的工作。结合南京地铁TAT标隧道限界测量探讨采用常规测量方法替代断面仪进行隧道横断面的确定并分析其精度。  相似文献   

渝遂高速公路中梁山隧道岩溶塌陷及涌水量分析   总被引：4，自引：1，他引：4  

付开隆 《水文地质工程地质》2005,32(2):107-110

修建于20世纪70年代的襄渝铁路中梁山隧道对测区水文地质环境影响很大。本文紧扣渝遂高速公路中梁山隧道横穿中梁山背斜且紧临襄渝铁路中梁山隧道这2大主题,详细分析隧道水文地质条件,预测了其涌水量和可能产生的岩溶塌陷。  相似文献   

水质分析在重庆笔架山隧道防腐设计中的应用   总被引：1，自引：0，他引：1  

康勇  李晓红  徐谋  阳光  夏小泉 《中国地质灾害与防治学报》2005,16(2):80-83

我国是拥有隧道数量最多及总长度最长的国家。同时也是隧道病害最严重的国家之一。由于隧道的主体是处于天然介质环境中的人工地下结构，在运营中会出现衬砌腐蚀等多种病害和危害。进行合理的防腐设计对隧道的安全、舒适、正常运营具重大意义。在南方富含腐蚀性介质地区，地下水容易沿衬砌的各种孔洞渗流到衬砌内侧，成为隧道渗漏水，对衬砌混凝土等产生侵蚀作用，造成衬砌腐蚀。故地下水对混凝土的侵蚀性是隧道防腐设计的重要组成部分。作者在掌握笔架山隧道工程地质、水文地质资料及查明环境水含腐蚀性介质的来源、成分基础上，利用隧道水简(化学)分析、地质调查、裂隙水统计等手段定性及定量评价环境地下水对衬砌混凝土腐蚀程度。认为基岩地下水不会对衬砌产生化学腐蚀。从而科学地修正了隧道的防腐设计。此结论及时反馈于施工，在后来的施工中取消了耐腐蚀混凝土及其它混凝土外加剂，节省了投资，加快了施工进度。  相似文献