Research on Deformation of Surrounding Rock and Mechanical Characteristics of Lining of Dolomitic Limestone Tunnel Based on Field Measurement and Numerical Analysis

Author(s):  
Wenqi Ding ◽  
Rongqing Zhu ◽  
Xuancuong Tran
2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Jin Zhang ◽  
Chuanhao Xi ◽  
Qian Zhang ◽  
Mengxue Wang

Carbonaceous slate is heterogeneous and anisotropic, which has a great influence on the stability of tunnel. In this paper, by means of laboratory test, field measurement, and numerical simulation, the surrounding rock stability and plastic zone distribution characteristics of the carbonaceous slate tunnel at different intersection angles are analyzed. First, combined with the Haibaluo tunnel project, Brazilian splitting and uniaxial compression tests of jointed carbonaceous slate are performed. The test results show that the tensile strength of carbonaceous slate is related to joint dip angle. When the joint angle is 0°, the tensile strength is the largest and decreases with the increase of the joint angle. The uniaxial strength of rock decreases first and then increases. Based on the discrete fracture network (DFN) technology, a calculation model is established. The calculation results show that the maximum displacement is 0.45 m, when the dip angle of the surrounding rock joint is 45°. The field measurement also shows that the dip angle of the surrounding rock joint has an important influence on the distribution of the plastic zone. When the joint dip angle is 45°, the plastic zone develops most strongly.


2008 ◽  
Vol 15 (5) ◽  
pp. 632-638 ◽  
Author(s):  
Yu-jun Zuo ◽  
Chun-an Tang ◽  
Wan-cheng Zhu ◽  
Di-yuan Li ◽  
Shu-cai Li

2012 ◽  
Vol 204-208 ◽  
pp. 4481-4485
Author(s):  
Bin Wang ◽  
Fu Jun Zhao ◽  
Wen Bin Peng

The current researches on bolt length are rarely concerned with self-bearing characteristics of anchorage surrounding rock,its stress response is seldom used to analyze the bolt effective length. Tangential stress σθ of surrounding rock is sensitive to mechanical variation of surrounding rock plastic failure fields. When surrounding rock bolted, the distribution curve of σθ presents internal and external peak values from the surface rock to the deep rock, which is verified by numerical simulation. Internal peak value of σθ curve increases with the bolt length, which means the bearing capacity of surrounding rock in plastic failure division is improved, correspondingly, external peak value decreases which shows the supporting behavior of the deep rock is weakened. The results of numerical simulations prove that there exists an effective value of bolt length. If bolt length beyond it, the bearing capacity of anchorage surrounding rock cannot be improved obviously.


2011 ◽  
Vol 90-93 ◽  
pp. 74-78 ◽  
Author(s):  
Jun Hu ◽  
Ling Xu ◽  
Nu Wen Xu

Fault is one of the most important factors affecting tunnel instability. As a significant and casual construction of Jinping II hydropower station, when the drain tunnel is excavated at depth of 1600 m, rockbursts and water inrush induced by several huge faults and zone of fracture have restricted the development of the whole construction. In this paper, a progressive failure progress numerical analysis code-RFPA (abbreviated from Rock Failure Process Analysis) is applied to investigate the influence of faults on tunnel instability and damaged zones. Numerical simulation is performed to analyze the stress distribution and wreck regions of the tunnel, and the results are consistent with the phenomena obtained from field observation. Moreover, the effects of fault characteristics and positions on the construction mechanical response are studied in details. Some distribution rules of surrounding rock stress of deep-buried tunnel are summarized to provide the reasonable references to TBM excavation and post-support of the drain tunnel, as well as the design and construction of similar engineering in future.


2006 ◽  
Vol 306-308 ◽  
pp. 1473-1478
Author(s):  
Wei Shen Zhu ◽  
Jian Hua Liu ◽  
Shu Cai Li

A brief description is given to the visco-plastic constitutive model of 3-D FLAC software and some treating methods for the numerical analysis. The excavation steps and the exerting time of excavation loads are determined in the light of the real construction process. The rockmass mechanical parameters are determined according to back analysis of in-situ measured displacement data. The analysis results of displacement and stability of the opening complex surrounding rocks in the construction process and in a long period of time after excavation completion are given.


2011 ◽  
Vol 255-260 ◽  
pp. 3749-3753 ◽  
Author(s):  
Wei Jian Yu

Since deformations of tunnel nearly mined area are larger, the reasonable support is very important. According to a side working face tunnel nearly mined area in one Mine, FLAC 2D was applied to numerical analyze on two type bolt net supported tunnel of “short bolt and long anchor cable” and “full anchor cable”. The results showed as follows: (1) plastic region of surrounding rock relatively large, which supported by short bolt and long anchor cable. Displacement reaches 27cm, the effect of this type supporting not significant; (2) The supporting of full anchor cable can effectively control deformation of tunnel, displacement less than 5cm, plastic region of surrounding rock also less than 2.3m. So, the supporting of full anchor cable can meet operating requirements.


2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Zhan-ping Song ◽  
Ten-tian Yang ◽  
An-nan Jiang

To study the tunnel stability at various static water pressures and determine the mechanical properties and deformation behavior of surrounding rock, a modified effective stress formula was introduced into a numerical integration algorithm of elastic-plastic constitutive equation, that is, closest point projection method (CPPM). Taking the effects of water pressure and seepage into account, a CPPM-based formula was derived and a CPPM algorithm based on Drucker-Prager yield criterion considering the effect of pore water pressure was provided. On this basis, a CPPM-based elastic-plastic numerical analysis program considering pore water pressure was developed, which can be applied in the engineering of tunnels and other underground structures. The algorithm can accurately take the effects of groundwater on stability of surrounding rock mass into account and it can show the more pronounced effect of pore water pressure on stress, deformation, and the plastic zone in a tunnel. The stability of water flooding in Fusong tunnel was systematically analyzed using the developed program. The analysis results showed that the existence of groundwater seepage under tunnel construction will give rise to stress redistribution in the surrounding rock mass. Pore water pressure has a significant effect on the surrounding rock mass.


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