scholarly journals Shaking Table Experiment on Seismic Performance of a Scaled-Down Arch Dam with Initial Crack

2021 ◽  
Vol 16 (6) ◽  
pp. 683-689
Author(s):  
Mohammed Noori Hussein ◽  
Ahmed Alkadhimi ◽  
Wisam Abdullah Najim ◽  
Hashim A. Almousawi
Keyword(s):  
Water Pressure ◽  
Initial Crack ◽  
Earthquake Magnitude ◽  
Arch Dam ◽  
Shaking Table ◽  
Earthquake Resistance ◽  
Seismic Excitations ◽  
Stress Evaluation ◽  
Arch Dams ◽  
Seismic Loadings

Seismic responses of cracked scaled-down arch dams were investigated by experiment on a shaking table. Two different curvature models (M1 and M2) were cast by using a plan concrete. Dams properties, including materials and dimensions, were carefully simulated. A significant earthquake magnitude with (7.7M) and water pressure were applied on the dam's models. Considering water and seismic loadings, the dynamic reactions of the arch dam's system were investigated. Both models showed crack overstresses or propagation on the dam's model as a result of seismic excitations. The arch dam with a higher degree of curvature was recorded 44 Mpa of stress evaluation which less by 30.7% of the arch dam with the lowest degree of curvature. The results indicated that raising the degree of curvature led to raising the dam's stability, earthquake resistance, less displacement, and less growth of tensile cracks.

Study on Deformation-Based Seismic Performance Index of Arch Dams

2012 ◽  
Vol 226-228 ◽  
pp. 1401-1405
Author(s):  
Xiao Wen Yao ◽  
Jian Qun Jiang
Keyword(s):  
Seismic Performance ◽  
Performance Index ◽  
Regional Scale ◽  
Arch Dam ◽  
Seismic Excitations ◽  
Dam Foundation ◽  
Seismic Safety ◽  
Arch Dams ◽  
Contraction Joints ◽  
Concrete Damage

Concrete arch dams are critical structures, the failure of which would lead to catastrophic effects on a regional scale. Considering the uncertainty characteristics of earthquake and the self-adjustment of inner force of arch dams, it’s necessary to investigate the seismic performance index of arch dam for holistically evaluating the seismic safety of arch dam-foundation system subjected to high intensity seismic excitations. By considering the contraction joints movement and concrete material nonlinearity, a series of dynamic response-history analyses of arch dam were carried out under increasing levels of earthquakes. Based on these analyses, the performance index of crest deformation is recommended for the seismic safety assessment of arch dam. And several performance stages of seismic response including the opening of contraction joints and the distribution of concrete damage are also investigated.

SHAKING TABLE TESTS AND NUMERICAL ANALYSIS FOR VERTICAL SEISMIC RESPONSE OF QUAYSIDE CONTAINER CRANES

2012 ◽  
Vol 12 (05) ◽  
pp. 1250034 ◽  
Author(s):  
Y. L. JIN ◽  
T. X. WU ◽  
Z. G. LI
Keyword(s):  
Numerical Analysis ◽  
Seismic Design ◽  
Large Scale ◽  
Shaking Table ◽  
Earthquake Resistance ◽  
Shaking Table Tests ◽  
Seismic Excitations ◽  
Engineering Structures ◽  
Scaled Model ◽  
Container Cranes

Vertical seismic performance is an important issue for the seismic design of large-scale engineering structures. The structure, which is relatively flexible and unrestricted vertically, may resonate and its response is obviously magnified under vertical earthquake excitations. The main objective of this study is to investigate the earthquake-resistance performance of a quayside container crane under vertical seismic excitations. To this end, a geometric-scaled model of 1:50 was firstly constructed according to the similitude law. Then using this model, a hammering modal test and a series of shaking table tests were successively conducted to obtain the dynamic characteristics and vertical seismic responses. Furthermore, the experimental results were compared with the computed results of prototype obtained from numerical analysis and agreed fairly well. From dynamic response results, it is found that the large-scale structure has relatively high vertical earthquake-resistance capacity and could satisfy the seismic design requirement. The findings reported in this paper are expected to provide some valuable information for studying other similar structures in the future.

Theory of Temperature Dynamic Control in Arch Dams and its Application

2012 ◽  
Vol 594-597 ◽  
pp. 738-741 ◽  
Author(s):  
Yin Duan ◽  
Xing Hong Liu ◽  
Xiao Lin Chang
Keyword(s):  
Real Time ◽  
Temperature Control ◽  
Control Method ◽  
Dynamic Control ◽  
Arch Dam ◽  
Real Time Control ◽  
New Techniques ◽  
Time Dynamic ◽  
Arch Dams ◽  
Time Control

Main factors of the temperature control and crack prevention in arch dams are summarized. The Space-time Dynamic Control method in pipe cooling process and the Temperature Real-time Control and Decision Database System are introduced to help for temperature real-time control and rapid analysis. Successful application of these new techniques in the construction of Dagangshan arch dam indicates that the proposed method are of significant effectiveness on the temperature control and crack prevention, and have good application prospect in practical project.

scholarly journals Crack-Considered Elastic Net Monitoring Model of Concrete Dam Displacement

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Jiingmei Zhang ◽  
Chongshi Gu
Keyword(s):  
Water Pressure ◽  
Elastic Net ◽  
Arch Dam ◽  
Time Dependent ◽  
Concrete Dams ◽  
Displacement Monitoring ◽  
Concrete Dam ◽  
Monitoring Model ◽  
Proposed Model ◽  
Dependent Component

Displacement monitoring data modeling is important for evaluating the performance and health conditions of concrete dams. Conventional displacement monitoring models of concrete dams decompose the total displacement into the water pressure component, temperature component, and time-dependent component. And the crack-induced displacement is generally incorporated into the time-dependent component, thus weakening the interpretability of the model. In the practical engineering modeling, some significant explaining variables are selected while the others are eliminated by applying commonly used regression methods which occasionally show instability. This paper proposes a crack-considered elastic net monitoring model of concrete dam displacement to improve the interpretability and stability. In this model, the mathematical expression of the crack-induced displacement component is derived through the analysis of large surface crack’s effect on the concrete dam displacement to improve the interpretability of the model. Moreover, the elastic net method with better stability is used to solve the crack-considered displacement monitoring model. Sequentially, the proposed model is applied to analyze the radial displacement of a gravity arch dam. The results demonstrate that the proposed model contributes to more reasonable explaining variables’ selection and better coefficients’ estimation and also indicate better interpretability and higher predictive precision.

scholarly journals Seismic Assessment of Arch Dams Using Fragility Curves

2015 ◽  
Vol 1 (2) ◽  
pp. 14-20 ◽  
Author(s):  
Vandad Kadkhodayan ◽  
S. Meisam Aghajanzadeh ◽  
Hasan Mirzabozorg
Keyword(s):  
Fragility Curves ◽  
Routine Data ◽  
Seismic Assessment ◽  
Arch Dam ◽  
The Other ◽  
Intensity Measure ◽  
Limit States ◽  
High Arch Dam ◽  
Arch Dams ◽  
Engineering Demand Parameter

In the present paper, the IDA approach is applied to analyzing a thin high arch dam. The parameters of Sa, PGA and PGV are used as intensity measure (IM) and the overstressed area (OSA) is utilized as engineering demand parameter (EDP) and then, three limit states are assigned to the considered structure using the IDA curves. Subsequently, fragility curves are calculated and it is showed that the PGA is a better parameter to be taken as IM. In addition, it is found that the utilizing the proposed methodology, quantifying the qualitative limit states is probable. At last, having the fragility curves and considering their slope in addition to the other routine data which can be extracted from these curves, one may be able to conclude that in what performance level the considered dam body seems to be weak and needs retrofitting works.

scholarly journals Effect of Seismic Loading on Variation of Pore Water Pressure During Pile Pull-Out Tests in Sandy Soils

2021 ◽  
Vol 27 (12) ◽  
pp. 1-12
Author(s):  
Haider N. Abdul Hussein ◽  
Qassun S. Mohammed Shafiqu ◽  
Zeyad S. M. Khaled
Keyword(s):  
Pore Water ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Seismic Loading ◽  
Shaking Table ◽  
Dense Sand ◽  
Pressure Transducers ◽  
Pull Out ◽  
Pullout Tests ◽  
Pile Model

Experimental model was done for pile model of L / D = 25 installed into a laminar shear box contains different saturation soil densities (loose and dense sand) to evaluate the variation of pore water pressure before and after apply seismic loading. Two pore water pressure transducers placed at position near the middle and bottom of pile model to evaluate the pore water pressure during pullout tests. Seismic loading applied by uniaxial shaking table device, while the pullout tests were conducted through pullout device. The results of changing pore water pressure showed that the variation of pore water pressure near the bottom of pile is more than variation near the middle of pile in all tests. The variation of pore water pressure after apply seismic loading is more than the variation before apply seismic loading near the middle of pile and near the bottom of pile and in loose and dense sand. Variation of pore water pressure after apply seismic loading and uplift force is less than the variation after apply seismic loading in loose sand at middle and bottom of pile.

Seismic Behaviour of Composite Panel Composed of Laminated Wood and Bearing Glass - Experimental Investigation

2013 ◽  
Vol 778 ◽  
pp. 698-705 ◽  
Author(s):  
Lidija Krstevska ◽  
Ljubomir Tashkov ◽  
Vlatka Rajčić ◽  
Roko Zarnic
Keyword(s):  
Earthquake Engineering ◽  
Experimental Testing ◽  
Shaking Table ◽  
Composite Panel ◽  
Seismic Excitations ◽  
Seismic Behaviour ◽  
Time Duration ◽  
Earthquake Motion ◽  
Scientific Project ◽  
Real Earthquake

Within the bilateral scientific project between the Institute of Earthquake Engineering and Engineering Seismology - UKIM-IZIIS, St. Cyril and Methodius University, Skopje, Republic of Macedonia and the Civil Engineering Faculty, University of Zagreb, Croatia, experimental testing of full scale composite timber-glass innovative panels was carried out on the seismic shaking table at IZIIS for the purpose of defining their behaviour and stability under real earthquake conditions. The seismic excitations selected for the shake-table testing of the model were four representative accelerograms recorded during the following earthquakes: El Centro, Petrovac, Kobe and Friuli. The idea was to investigate the seismic behavior of the model under several types of earthquakes, considering their different frequency content, peak acceleration and time duration. The performed tests showed clearly the behaviour of the composite panels and the failure mechanism under strong earthquake motion.

Practical Constitutive Model in the Application of Arch Dam Shape Design Calculation

2011 ◽  
Vol 105-107 ◽  
pp. 857-861
Author(s):  
Hong Wang ◽  
Chong Jin ◽  
Xiao Zhou Xia ◽  
Hong Yuan
Keyword(s):  
Constitutive Model ◽  
Mechanical Performance ◽  
Water Pressure ◽  
Safety Margin ◽  
Least Square Method ◽  
High Water ◽  
Arch Dam ◽  
Least Square ◽  
Design Calculation ◽  
High Arch Dam

A fitting curve of stress-strain relation given is applied in numerical analyzing based on Legendre orthogonal polynomial and least square method. The nonlinear constitutive model is employed to examine the shape of an arch dam. For the asymmetries and high water pressure, the safety of High Arch Dam is one of key issues in the design and construction of High Arch Dam. The simulation results show that the basic mechanical performance index is symmetrical distribution. The dam mainly bears pressure and no obvious tensile stress exists in the dam when water level is normal. Material yields in dam heel when 1.4 times overloading is considered. It can be concluded that the dam is reliable and the safety margin is satisfactory.

Sign in / Sign up

Export Citation Format

Share Document