Effect of the impounding process on the overall stability of a high arch dam: a case study of the Xiluodu dam, China

2015 ◽  
Vol 8 (11) ◽  
pp. 9023-9041 ◽  
Author(s):  
Danni Luo ◽  
Peng Lin ◽  
Qingbin Li ◽  
Dong Zheng ◽  
Hongyuan Liu
2014 ◽  
Vol 45 ◽  
pp. 164-184 ◽  
Author(s):  
Peng Lin ◽  
Tianhui Ma ◽  
Zhengzhao Liang ◽  
Chun An Tang ◽  
Renkun Wang

2020 ◽  
Vol 10 (2) ◽  
pp. 524 ◽  
Author(s):  
Tao Yin ◽  
Qingbin Li ◽  
Yu Hu ◽  
Sanda Yu ◽  
Guohe Liang

General studies examining reservoir bank deformation during its impoundment primarily consider the coupling effect between the seepage field and the stress field, but thermal field variation in the bedrock and its effect are rarely considered. In this paper, a case study concerning a 285.5 m high arch dam project, where a valley narrowing deformation occurs after the initial impoundment, is implemented. An analysis of in situ measurement is given to interpret the causes of the unique hydro-thermal phenomenon of the project. Possible reasons for the valley narrowing deformation pattern are discussed. A numerical model based on the thermo-hydro-mechanical (THM) coupling theory of porous medium is used to calculate the evolution processes of the thermal, seepage, and stress fields of the area after impoundment of the reservoir. The simulated deformation trend and pattern of the river valley are consistent with the monitoring data. The results demonstrate that water infiltration after impounding cools the bedrock and the temperature decrease makes the bedrock contract, which induces the narrowing deformation of the valley. Factor analysis of the hydrothermal field shows that temperature variation is the main cause of long-term deformation. Thus, it shall be considered as a key factor in terms of structural safety assessment. Furthermore, sensitivity analysis of the hydraulic conductivities of rock strata suggests that future development of the deformation can be eased off if the anti-seepage method is adopted on the bedrock.


2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Tianhui Ma ◽  
Zhiqiang Feng ◽  
Chun'an Tang ◽  
Peng Lin ◽  
Kedar Prasad Yadav

The RFPA3D is used to establish a fine finite element model of 6.63 million elements, which realizes the fine simulation of the stability of the Xiluodu arch dam under layered, overall, multiworking conditions and multistress fields, and the cracking and failure process under overload. The structural design scheme of the arch dam and the corresponding foundation treatment design are evaluated. The model fully reflects the measures of dam shape structure design, angle fitting structure design, and foundation concrete replacement in the Xiluodu arch dam technical design stage. The RFPA3D adopts the mesoelement elastic damage model, which considers the Mohr–Coulomb criterion of shear fracture and the maximum tensile failure criterion, and assumes that the mechanical properties of the element satisfy Weibull distribution to consider its heterogeneity. The simulation results show that, under normal load conditions, the dam foundation surface after comprehensive reinforcement has better overall stability, the stress and deformation of the dam body have good symmetry, and the overload factor of crack initiation under overload calculation K1 = 2P0 (P0 is normal water load), the nonlinear deformation overload factor K2 = 3.5–4P0, and the limit load factor K3 = 7.5–8.0P0, dam safety can be satisfied. The RFPA3D is used to establish a superlarge fine model to study the overall stability of the high arch dam, which provides an effective method for analysis and research of other large hydraulic projects in the world.


2018 ◽  
Vol 8 (12) ◽  
pp. 2555 ◽  
Author(s):  
Peng Lin ◽  
Pengcheng Wei ◽  
Weihao Wang ◽  
Hongfei Huang

It is of great significance to study the cracking risk, the overall stability, and the reinforcement measures of arch dams for ensuring long-term safety. In this study, the cracking types and factors of arch dams are summarized. By employing a nonlinear constitutive model relating to the yielding region, a fine three-dimensional finite element simulation of the Xulong arch dam is conducted. The results show that the dam cracking risk is localized around the outlets, the dam heel, and the left abutment. Five dam stress zones are proposed to analysis dam cracking state base of numerical results. It is recommended to use a shearing-resistance wall in the fault f57, replace the biotite enrichment zone with concrete and perform consolidation grouting or anchoring on the excavated exposed weak structural zone. Three safety factors of the Xulong arch dam are obtained, K_1 = 2~2.5; K_2 = 5; K_3 = 8.5, and the overall stability of the Xulong arch dam is guaranteed. This study demonstrates the significance of the cracking control of similar high arch dams.


2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Baoquan Yang ◽  
Lin Zhang ◽  
Enlong Liu ◽  
Jianhua Dong ◽  
Honghu Zhu ◽  
...  

Geomechanical model testing is an important method for studying the overall stability of high arch dams. The main task of a geomechanical model test is deformation monitoring. Currently, many types of deformation instruments are used for deformation monitoring of dam models, which provide valuable information on the deformation characteristics of the prototype dams. However, further investigation is required for assessing the overall stability of high arch dams through analyzing deformation monitoring data. First, a relationship for assessing the stability of dams is established based on the comprehensive model test method. Second, a stability evaluation system is presented based on the deformation monitoring data, together with the relationships between the deformation and overloading coefficient. Finally, the comprehensive model test method is applied to study the overall stability of the Jinping-I high arch dam. A three-dimensional destructive test of the geomechanical model dam is conducted under reinforced foundation conditions. The deformation characteristics and failure mechanisms of the dam abutments and foundation were investigated. The test results indicate that the stability safety factors of the dam abutments and foundation range from 5.2 to 6.0. These research results provide an important scientific insight into the design, construction, and operation stages of this project.


2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Peng Lin ◽  
Xiaoli Liu ◽  
Hong-Xin Chen ◽  
Jinxie Kim

A dam ant colony optimization (D-ACO) analysis of the overall stability of high arch dams on complicated foundations is presented in this paper. A modified ant colony optimization (ACO) model is proposed for obtaining dam concrete and rock mechanical parameters. A typical dam parameter feedback problem is proposed for nonlinear back-analysis numerical model based on field monitoring deformation and ACO. The basic principle of the proposed model is the establishment of the objective function of optimizing real concrete and rock mechanical parameter. The feedback analysis is then implemented with a modified ant colony algorithm. The algorithm performance is satisfactory, and the accuracy is verified. Themgroups of feedback parameters, used to run a nonlinear FEM code, and the displacement and stress distribution are discussed. A feedback analysis of the deformation of the Lijiaxia arch dam and based on the modified ant colony optimization method is also conducted. By considering various material parameters obtained using different analysis methods, comparative analyses were conducted on dam displacements, stress distribution characteristics, and overall dam stability. The comparison results show that the proposal model can effectively solve for feedback multiple parameters of dam concrete and rock material and basically satisfy assessment requirements for geotechnical structural engineering discipline.


2013 ◽  
Vol 3 (3) ◽  
Author(s):  
Mohammad Hariri-Ardebili ◽  
Hasan Mirzabozorg ◽  
M. Kianoush

AbstractDam-reservoir interaction is one of the classic coupled problems in which two various environments with different physical characteristics are in contact with each other on interface boundary. Consideration of such interaction is important in design of new dams as well as on safety evaluation of the existing ones. In the present study, the effect of hydrodynamic pressures at various reservoir operational levels on seismic behavior of an arch dam is investigated. Dez ultra-high arch dam in Iran was selected as case study and all contraction and peripheral joints were simulated using node-to-node contact elements which have the ability of opening/closing and tangential movement. In addition, stage construction effects including joint grouting based on available construction reports were considered. The reservoir was assumed to be compressible and the foundation rock was modeled to account for its flexibility. The TABAS earthquake record was used to excite the finite element model of dam-reservoir-foundation system. It was found that dam-reservoir interaction has significant structural effects on the system and generally, operating the considered arch dam at different water levels can highly affects the distribution of the crack prone area under the maximum credible earthquake.


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