Study on Stress Characteristics of Multi-arch Tunnel Lining under Weak Surrounding Rock Conditions Based on Field Measurement

In the aspect of stability analysis of tunneling engineering, geomechanical model test is an important research method. A similar material is the prerequisite for the success of geomechanical model test. In the field of major engineering applications, a variety of similar materials are prepared for different geological conditions of surrounding rock and applied in some major engineering. With the use of standard sand, fine sand, and silt clay as materials, similar materials for weak surrounding rock were developed. Based on the orthogonal design method, through the direct shear test, the range analysis and variance analysis of various factors affecting the physical and mechanical parameters of weak surrounding rock are carried out. The results show similar material can meet the requirements in weak surrounding rock. Standard sand is the key factor that influences the internal friction angle of similar materials, and silt clay is the key factor affecting the cohesion of similar materials. Similar materials can meet the elastic modulus and severe requirements of the weak surrounding rock and can be used for the weak surrounding rock engineering. The new type of similar material configuration is widely used in shallow buried tunnel entrance section and urban shallow buried excavation engineering, in addition to tunnel engineering in loess stratum, and the problems of engineering design and construction are solved through geomechanical model test.

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The Slabbing Mechanics Analysis of the Tunnel Lining

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.3530 ◽

2011 ◽

Vol 243-249 ◽

pp. 3530-3537

Author(s):

Zu Song Wu ◽

Guang Qi Chen ◽

Kou Ki Zen ◽

Xin Rong Liu

Keyword(s):

Surrounding Rock ◽

Tunnel Lining ◽

The Self ◽

Road Tunnel ◽

The Road ◽

Mechanics Analysis ◽

The Stability

When the road tunnel is excavated, the multi lining is used to being applied. In order to keep the surrounding rock stabilize and arouse the self-stability of the surrounding rock, building the first support is essential. But the slabbing often occurs near the spring line on the surface of the first lining, and because the slabbling is a common failing and not attracted our most attentions, it will develop to the crack and threaten the stability of the structure finally. This paper uses the line elastic method to analyze the mechanics that causes this slabbing phenomenon via the interaction between the surrounding rock and the first lining, and suggests the measure that escape the slabbing.

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Study on Stability and Plastic Zone Distribution of Tunnel with Thin Carbonaceous Slate at Different Dip Angles

Shock and Vibration ◽

10.1155/2021/6345879 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Jin Zhang ◽

Chuanhao Xi ◽

Qian Zhang ◽

Mengxue Wang

Keyword(s):

Tensile Strength ◽

Plastic Zone ◽

Field Measurement ◽

Joint Angle ◽

Rock Joint ◽

Great Influence ◽

Surrounding Rock ◽

Test Field ◽

Maximum Displacement ◽

Dip Angle

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.

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Tunnel Bottom Cavity Laws of Heavy-Haul Railway Tunnel under Train Load and Groundwater in Weak Surrounding Rock Condition

KSCE Journal of Civil Engineering ◽

10.1007/s12205-021-5953-y ◽

2021 ◽

Author(s):

Ziqiang Li ◽

Zheng Li ◽

Weiwei Huang ◽

Zhifan Xu ◽

Wengang Zhang ◽

...

Keyword(s):

Surrounding Rock ◽

Railway Tunnel ◽

Bottom Cavity ◽

Heavy Haul ◽

Heavy Haul Railway ◽

Weak Surrounding Rock

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IBIEM Analysis of Dynamic Response of a Shallowly Buried Lined Tunnel Based on Viscous-Slip Interface Model

Advances in Civil Engineering ◽

10.1155/2019/1025483 ◽

2019 ◽

Vol 2019 ◽

pp. 1-14

Author(s):

Xiaojie Zhou ◽

Qinghua Liang ◽

Zhongxian Liu ◽

Ying He

Keyword(s):

Stress Concentration ◽

Incident Wave ◽

Dynamic Stress ◽

Surface Displacement ◽

Surrounding Rock ◽

Tunnel Lining ◽

Wave Frequency ◽

Dynamic Stress Concentration ◽

Interface Model ◽

Rock Interface

A viscous-slip interface model is proposed to simulate the contact state between a tunnel lining structure and the surrounding rock. The boundary integral equation method is adopted to solve the scattering of the plane SV wave by a tunnel lining in an elastic half-space. We place special emphasis on the dynamic stress concentration of the lining and the amplification effect on the surface displacement near the tunnel. Scattered waves in the lining and half-space are constructed using the fictitious wave sources close to the lining surfaces based on Green’s functions of cylindrical expansion and the shear wave source. The magnitudes of the fictitious wave sources are determined by viscous-slip boundary conditions, and then the total response is obtained by superposition of the free and scattered fields. The slip stiffness and viscosity coefficients at the lining-surrounding rock interface have a significant influence on the dynamic stress distribution and the nearby surface displacement response in the tunnel lining. Their influence is controlled by the incident wave frequency and angle. The hoop stress increases gradually in the inner wall of the lining as sliding stiffness increases under a low-frequency incident wave. In the high-frequency resonance frequency band, where incident wave frequency is consistent with the natural frequency of the soil column above the tunnel, the dynamic stress concentration effect is more significant when it is smaller. The dynamic stress concentration factor inside the lining decreases gradually as the viscosity coefficient increases. The spatial distribution and the displacement amplitudes of surface displacement near the tunnel change as incident wave frequency and angle increase. The effective dynamic analysis of the underground structure under an actual strong dynamic load should consider the slip effect at the lining-surrounding rock interface.

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STUDY ON VERIFICATION BY FIELD MEASUREMENT AND APPLICATION OF SINGLE-SHELL STRUCTURE IN TUNNEL LINING

Doboku Gakkai Ronbunshuu C ◽

10.2208/jscejc.63.1079 ◽

2007 ◽

Vol 63 (4) ◽

pp. 1079-1090

Author(s):

Toshio TOSAKA ◽

Toshio ABE ◽

Toshihiro ASAKURA

Keyword(s):

Shell Structure ◽

Field Measurement ◽

Tunnel Lining ◽

Single Shell

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Research on Spacial Displacement Regulations in Soft Surrounding Rock Tunnel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.886 ◽

2013 ◽

Vol 690-693 ◽

pp. 886-889

Author(s):

Bao Long Lin

Keyword(s):

High Speed ◽

Surrounding Rock ◽

Construction Process ◽

High Speed Rail ◽

Tunnel Stability ◽

Construction Methods ◽

Minimum Principal Stress ◽

Initial Support ◽

Rock Tunnel ◽

Weak Surrounding Rock

Based on the engineering background of Dongkeling tunnel of Guizhou-Guangzhou high-speed rail, construction process in soft surrounding rock is simulated by using finite difference software——FLAC according to large-deformation characteristics in water-rich and weathering altered granite weak surrounding rock. Several aspects, such as vault settlement, invert uplift, clearance convergence, surface settlement, the maximum and minimum principal stress of the initial support and plastic zone of surrounding rock, are analyzed to determine the tunnel stability with different construction methods.

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