Analysis of Seismic Damage of Underground Powerhouse Structure of Hydropower Plants Based on Dynamic Contact Force Method

Based on the characteristics of the dynamic interaction between an underground powerhouse concrete structure and its surrounding rock in a hydropower plant, an algorithm of dynamic contact force was proposed. This algorithm enables the simulation of three states of contact surface under dynamic loads, namely, cohesive contact, sliding contact, and separation. It is suitable for the numerical analysis of the dynamic response of the large and complex contact system consisting of underground powerhouse concrete structure and the surrounding rock. This algorithm and a 3D plastic-damage model were implemented in a dynamic computing platform, SUCED, to analyze the dynamic characteristics of the underground powerhouse structure of Yingxiuwan Hydropower Plant. By comparing the numerical results and postearthquake investigations, it was concluded that the amplitude and duration of seismic waves were the external factors causing seismic damage of the underground powerhouse structure, and the spatial variations in structural properties were the internal factors. The existence of rock mass surrounding the underground powerhouse was vital to the seismic stability of the structure. This work provides the theoretical basis for the anti-seismic design of underground powerhouse structures.

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Earthquake and Underground Powerhouse: On the Aseismic Issues of Baihetan Underground Cavern Complex

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.594-597.1753 ◽

2012 ◽

Vol 594-597 ◽

pp. 1753-1761

Author(s):

Xian Lun Leng ◽

Jia Jin Liu ◽

Cui Zhen ◽

Sheng Qian

Keyword(s):

Safety Evaluation ◽

Hydropower Plant ◽

Seismic Stability ◽

Alternative Scheme ◽

Underground Powerhouse ◽

Seismic Displacement ◽

Underground Cavern ◽

Design Basis ◽

Rock Cavern ◽

Under Construction

A hydropower plant is usually the major electricity supplier in the region, the failure of underground powerhouse in an earthquake may cause not only the damage to itself, but also secondary disasters to the region in a way of an electricity outage. Seismic stability of these underground complexes is required to be seriously addressed. The underground cavern complex of the Baihetan hydropower plant in Yunnan Province, China, is currently the world's largest underground rock cavern group under construction. Aseismic issues of the underground cavern complex are discussed in this paper. On the basis of this research, seismic variables of the Baihetan project are firstly determined for Design Basis Earthquake and Safety Evaluation Earthquake. The artificial seismic motions for the dynamic analyses are simulated. Two alternative scheme of layout plans of the underground cavern complex are studied, with full 3-D elasto-plastic dynamic response analyses based on the parameters given by the cyclic dynamic loading tests with medium strain rate. The seismic response of seismic displacement and failure zones of each scheme are studied, respectively. A performance verification of the supporting measures during earthquake is also discussed. The results indicate that in spite a wider powerhouse cavern, the scheme "A" which involves a gallery-shaped surge chamber is more stabilized during an earthquake than the scheme "B" whom with barrel-shaped surge chambers. The underground cavern complex with scheme "B" is relatively stable under Design Basis Earthquake and Safety Evaluation Earthquake, despite a minor damage of the surrounding rock. And the implementation of the proposed support system may further guaranteed a safe state of the underground cavern complex in earthquake events.

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Numeric Simulation of Fracture Extension within Surrounding Rock under Continuous Excavation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.1473 ◽

2011 ◽

Vol 71-78 ◽

pp. 1473-1477

Author(s):

Gui Lin Li ◽

Li Wang ◽

Yuan Chun Mao

Keyword(s):

Underground Mining ◽

Progressive Failure ◽

Damage Model ◽

Complex Stress ◽

Complex Stress State ◽

Surrounding Rock ◽

Similar Material ◽

Underground Powerhouse ◽

Numeric Simulation ◽

Damage Law

This paper aims at progressive failure within surrounding rock under continuous excavation, such as mining, underground powerhouse building, etc. A meso-damage model is proposed, which include the damage law under complex stress state for brittle materials, and the damage evolution based on stiffness degradation. The damage model is embedded into the FEM program. To test and very the damage model, a example of continuous excavation of underground mining is simulated. The result shows that the crack field growth is in accordance with that the similar material experiment.

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Seismic stability of the underground main pipeline

Proceedings of the Mavlyutov Institute of Mechanics ◽

10.21662/uim2011.1.027 ◽

2011 ◽

Vol 8 (1) ◽

pp. 275-286

Author(s):

R.G. Yakupov ◽

D.M. Zaripov

Keyword(s):

Laplace Transformation ◽

Seismic Waves ◽

Generalized Functions ◽

Seismic Stability ◽

Main Pipeline ◽

Motion Equations ◽

Numerical Example ◽

Earthquake Force ◽

Deformed State

The stress-deformed state of the underground main pipeline under the action of seismic waves of an earthquake is considered. The generalized functions of seismic impulses are constructed. The pipeline motion equations are solved with used Laplace transformation by the time. Tensions and deformations of the pipeline have been determined. A numerical example is reviewed. Diagrams of change of the tension depending on earthquake force are provided in earthquake-points.

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Evaluation of vehicular contact force on bridge joints by vibration responses and object detection

IABSE Congress, Christchurch 2021: Resilient technologies for sustainable infrastructure ◽

10.2749/christchurch.2021.0396 ◽

2021 ◽

Author(s):

Di Su ◽

Yuichiro Tanaka ◽

Tomonori Nagayama

Keyword(s):

Object Detection ◽

Contact Force ◽

Dynamic Contact ◽

Contact Forces ◽

Expansion Joints ◽

Cyclic Movements ◽

Bridge Joints ◽

Vibration Responses ◽

On The Road ◽

Board System

<p>Expansion joints on bridges should accommodate cyclic movements to minimize imposition of secondary stresses in the structure. However, these joints are highly susceptible to severe and repeated vehicular impact that results their inherent discontinuity. In this paper, a portable on- board system including accelerometers and a drive recorder to evaluate the vehicular contact force on bridge joints is proposed. First, from the acceleration responses of the vehicle, the contact force exerted on the road surface is estimated from a half-car model by Kalman Filter. Next, extraction of the expansion joints is performed by object detection from videos taken by the drive recorder. Finally, a relative comparison of the contact forces acting on joints is performed, with location identification on the map. The proposed system benefits to utilize the dynamic contact forces results from on-board system to detect the potential risky joints more precisely and efficiently.</p>

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Study on Deformation and Damage of Rock Mass Subject to High In Situ Stress by Using a Elastoplastic Damage Model and Considering the Impact of Weak Planes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.838-841.705 ◽

2013 ◽

Vol 838-841 ◽

pp. 705-709

Author(s):

Yun Hao Yang ◽

Ren Kun Wang

Keyword(s):

Rock Mass ◽

Large Scale ◽

Damage Model ◽

Back Analysis ◽

In Situ Stress ◽

Surrounding Rock ◽

High In Situ Stress ◽

Underground Caverns ◽

The Impact

Large scale underground caverns are under construction in high in-situ stress field at Houziyan hydropower station. To investigate deformation and damage of surrounding rock mass, a elastoplastic orthotropic damage model capable of describing induced orthotropic damage and post-peak behavior of hard rock is used, together with a effective approach accounting for the presence of weak planes. Then a displacement based back analysis was conducted by using the measured deformation data from extensometers. The computed displacements are in good agreement with the measured ones at most of measurement points, which confirm the validities of constitutive model and numerical simulation model. The result of simulation shows that damage of surrounding rock mass is mainly dominated by the high in-situ stress rather than the weak planes and heavy damage occur at the cavern shoulders and side walls.

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