Case Study of the Effect of Rainfall Infiltration on a Tunnel Underlying the Roadbed Slope with Weak Inter-Layer

Fan, Shenggen; Song, Zhanping; Zhang, Yu-Wei; Liu, Naifei

doi:10.1007/s12205-020-1165-0

Cited by 37 publications

(17 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many studies analyze the influence of rainfall on slope stability, and two main methods are utilized: (1) field investigations and monitoring data analysis through model tests [20][21][22][23] and (2) numerical simulations, such as the finite element method and finite difference method [24][25][26][27][28]. Numerical simulation has advantages in obtaining some key physical quantities, which are difficult to measure in the model tests and field investigations.…”

Section: Introductionmentioning

confidence: 99%

Effect of Rainfall Pattern and Crack on the Stability of a Red Bed Slope: A Case Study in Yunnan Province

Zhu

Sheng

et al. 2021

Advances in Civil Engineering

View full text Add to dashboard Cite

Red bed slopes in the southwest of China are associated with a grant number of geological hazards, such as landslides, mud-rock flows, and rock blocks falling, which are vital problems in geotechnical engineering. The damage can be induced or triggered due to a series of human and environmental activities, such as excavation, concentrated or long-term rainfall, earthquake, and fluctuation of groundwater level. According to the field observations and geological exploration results, a small-scale landslide was observed on January 10, 2016, after excavation along XiaoMo highway in Yunnan Province. A numerical model in actual size using GeoStudio software based on this typical red bed engineering slope was established in this study. Back analyses and laboratory tests were used to obtain the mechanical parameters of the geomaterial inside the slope. The historic rainfall data of Mengla County from July to September in 2016 was utilized as the flux boundary in analyzing the seepage variation features and the stability of the engineering slope in the rainy season. One major tension crack was set in the shallow region of the silty clay according to the geology survey to perform the disturbance of excavation on the geomorphology of the slope. Attempts were made to establish the anisotropic permeability of the crack induced by the complex fillings, and differences in the hydraulic response between the cracking and completed slope during the rainfall process were discussed. The result shows that the factor of safety of the slope without crack before the rainfall is 1.076, and the slope is considered in the state of the critical limit equilibrium, which is in accordance with the previous state of the slope under real conditions. The pore water pressure variations of the monitor points in the shallow region of the completed slope present close compliance with the rainfall intensity subjected to different rainfall patterns, which also controls the distribution of the plastic zone in the slope after rainfall. The comparisons in the seepage field and plastic zone between the cracking and completed slope reveal that the crack can shorten the infiltration path effectively, and the higher the permeability coefficient in the vertical direction is, the larger the pore water pressure increasing zone is and the higher the underground water level is, which should be paid more attention in highway constructions.

show abstract

Section: Introductionmentioning

confidence: 99%

Effect of Rainfall Pattern and Crack on the Stability of a Red Bed Slope: A Case Study in Yunnan Province

Zhu

Sheng

et al. 2021

Advances in Civil Engineering

View full text Add to dashboard Cite

show abstract

“…Engineering practice shows that rainfall often triggers water and mud inrush; water is an important factor that induces the instability of rock surrounding tunnels (Li et al 2009;Lin et al 2019). Water infiltrates into the surrounding rock of a tunnel through rock interfaces such as joints and cracks, which lead to the surrounding rock losing its stability and deteriorating under the action of softening, soaking and erosion, which is then followed by collapse and even water gushing and mud bursting (Fan et al 2020;Xu and Li 2010;Yu et al 2020b). In addition, water and mud inrush will seriously affect the progress of tunnel construction and may even result in casualties, and most underground geological disasters pose a risk to surface subsidence and affect the water environment (Li et al 2016(Li et al , 2017Parise and Lollino 2011;Song et al 2012).…”

Section: Introductionmentioning

confidence: 99%

The failure characteristics around shallow buried tunnels under rainfall conditions

Wang

Zheng

et al. 2021

Geomatics, Natural Hazards and Risk

View full text Add to dashboard Cite

The instability of weak surrounding rock around shallow buried tunnels induced by rainfall is a challenge for tunnel engineering and threatens construction safety. To reveal the influence of rainfall on the rock surrounding a tunnel, the results of experiments on the failure of surrounding rock under different rainfall intensities and durations using a self-developed test system are presented. First, the stress and seepage behaviors of the surrounding rock under rainfall were analysed, and the results showed that the stress increased while the pore water pressure decreased as the rainfall intensity decreased. It was more difficult to maintain vault collapse as rainfall intensity increased, and the particle erosion in the model intensified as the rainfall duration increased. The change in pore water pressure was greater than the change in stress, but the stress and pore water pressures influenced each other during rainfall. The influence of rainfall on the rock at the top of the tunnel was greater than that at the two sides of the tunnel because the seepage channels at the top of the tunnel were more developed and collapsed more easily due to smaller stresses. According to the phenomena of the surrounding rock observed during the test, the evolution of progressive failure under rainfall was roughly divided into eight stages: stability, water drop, continuous water flow, partial collapse, mud and water mixture, vault collapse, throughgoing collapse, and massive water and mud gushing. Furthermore, the final failure pattern of the surrounding rock consists of an excavation disturbance zone, vault damage zone and collapse failure zone. This research helps to reveal the progressive failure of surrounding rock around tunnels under rainfall conditions and can be used as a reference for designing disaster prevention strategies in practical engineering.

show abstract

“…In recent years, subway construction has developed rapidly. Nowadays, the common methods in urban subway construction include open excavation, cover excavation [1][2][3], and concealed excavation [4,5]. Among them, the concealed excavation method includes drilling and blasting method, shield method, TBM, and pipe jacking method.…”

Section: Introductionmentioning

confidence: 99%

Risk Analysis of Tunnel Construction Scheme Change based on Field Monitoring and Numerical Analysis

Song

Tian

et al. 2021

Advances in Civil Engineering

View full text Add to dashboard Cite

Because of the surrounding environment restriction, some sections of the Lanzhou Metro Line 2 were forced to change the original open excavation method to the concealed excavation method. Among them, the ingate is the transitional section connecting the shaft and the cross passage, which is accompanied by the force conversion of the structure during the plan change process, and accidents are prone to occur. Combining this project situation, a construction scheme for turning the shaft from the cross passage into the ingate of mine line was proposed, and the finite element software is used to simulate the scheme. Numerical analysis shows that the stability of the tunnel supporting structure, shaft, and cross passage all meet the design requirements. The final ground settlement caused by the proposed construction method is 7.1 mm, and the settlement of the vault is 11.97 mm. It also turns out that the proposed construction method causes less deformation, and the method can be applied to the construction of the ingate conversion. The rationality of the method and numerical model was further verified by the comparison between the monitored data of surface settlement and vault sinking and numerical simulation results. Finally, the modified concealed excavation method and the original open excavation construction method is compared. It is concluded that the concealed excavation method is superior to the original open excavation method in terms of construction schedule, construction safety, economic benefits, and impact of construction on the surrounding environment. It indicates that it is a good choice to replace the construction method early if necessary. The successful implementation of this project can provide a reference for the design and implementation of similar urban subway projects.

show abstract

Case Study of the Effect of Rainfall Infiltration on a Tunnel Underlying the Roadbed Slope with Weak Inter-Layer

Cited by 37 publications

References 31 publications

Effect of Rainfall Pattern and Crack on the Stability of a Red Bed Slope: A Case Study in Yunnan Province

Effect of Rainfall Pattern and Crack on the Stability of a Red Bed Slope: A Case Study in Yunnan Province

The failure characteristics around shallow buried tunnels under rainfall conditions

Risk Analysis of Tunnel Construction Scheme Change based on Field Monitoring and Numerical Analysis

Contact Info

Product

Resources

About