scholarly journals Study on Optimization of Temperature Control Measures for Structure Concrete of Arc Dam

2021 ◽  
Author(s):  
Lei Zhang ◽  
Xiaofang Ma ◽  
Heng Zhao ◽  
Lei Zheng ◽  
Shouxun Ma
Keyword(s):  
Phase I ◽  
Temperature Stress ◽  
Temperature Control ◽  
Simulation Analysis ◽  
Complex Structure ◽  
Arch Dam ◽  
Control Measures ◽  
3D Fem ◽  
Water Pipes ◽  
Cooling Temperature

As the gate pier bracket of an arch dam are of complex structure which is characterized by use of high-grade concrete and more cement, higher adiabatic temperature rise, it is rather difficult to control temperature and vulnerable for cracking, and the cracks would absolutely affect the integrity, endurance and safety of pier gate bracket. It is necessary to take reasonable temperature control measures to reduce temperature stress during the construction and prevent cracking. This paper takes the gate pier bracket at the middle-hole dam section to perform simulation analysis of temperature field and stress field under different temperature control measures by 3D FEM. It proves that such measures as densifying water pipes, improving Phase I target cooling temperature appropriately, reducing Phase I cooling temperature falling variation and keeping insulation in low-temperature season can help reduce temperature stress and prevent cracking with good results.

Temperature Control Measures Optimization of RCC Gravity Dam

2012 ◽  
Vol 226-228 ◽  
pp. 1153-1156 ◽  
Author(s):  
Shu Ping Huang ◽  
Jian Yun Fu ◽  
Yan Cai Li
Keyword(s):  
Temperature Control ◽  
Simulation Analysis ◽  
Control Measure ◽  
Control Measures ◽  
Gravity Dam ◽  
Mass Concrete ◽  
Dam Construction ◽  
Construction Technology ◽  
3D Fem ◽  
Single Temperature

With the continuous development of dam construction technology, the RCC dam becomes one of the most popular types of dam in the world with its unique advantages. Temperature control measures research is one of the key issues of design and construction of mass concrete structures. How to choose the proper temperature control measures to prevent concrete cracks becomes the important problem of dam construction technology. In a RCC gravity dam, the climate environment is so severe that a single temperature control measure can’t meet the requirements of temperature control and crack prevention. In this paper, 3D FEM simulation analysis is used to calculate temperature field and thermal creep stress field during the whole construction process. According to the simulation results, the temperature control measures design of the dam has been comprehensively evaluated and the temperature control measures of this project have been put forward.

scholarly journals Research on concrete temperature control measures in deep hole area of super high arch dam

2021 ◽  
Vol 826 (1) ◽  
pp. 012035
Author(s):  
Yuchen Fu ◽  
Yaosheng Tan ◽  
Chunfeng Liu ◽  
Lei Pei ◽  
Yajun Wang ◽  
...  
Keyword(s):  
Temperature Control ◽  
Arch Dam ◽  
Control Measures ◽  
Deep Hole ◽  
High Arch Dam ◽  
Hole Area ◽  
Concrete Temperature

Study on Concrete Dam Temperature Evaluation Based on Distributed Optical Fiber Temperature

2012 ◽  
Vol 204-208 ◽  
pp. 457-462
Author(s):  
Yao Ying Huang ◽  
Dan Dan Liu ◽  
Li Xin Qu ◽  
Yi Hong Zhou
Keyword(s):  
Optical Fiber ◽  
Temperature Control ◽  
Evaluation System ◽  
Weak Link ◽  
Arch Dam ◽  
Control Measures ◽  
Entropy Weight ◽  
Weighting Method ◽  
Technical Requirements ◽  
Distributed Optical Fiber

The dam concrete material properties wre influenced by the implementation of temperature control measures on site. The weekly temperature evaluation system has been set up in order to evaluate current temperature control measures, combining with the distributed optical fiber temperature control techniques and construction technical requirements. The system has been applied to a concrete arch dam under construction in southwest China which established multi-objective fuzzy mathematical model by synthetic weighting method that was a combination of experts scoring method and entropy weight method. Practice shows that the system can estimate weak link of this week and give guidance to the temperature control’s adjustment of the following week.

Simulation Analysis of Concrete Temperature and Stress of Plant Elbow Section of Sluice Dam

2011 ◽  
Vol 368-373 ◽  
pp. 3011-3014
Author(s):  
Shou Kai Chen ◽  
Li Xia Guo
Keyword(s):  
Concrete Structure ◽  
Thermal Field ◽  
Simulation Analysis ◽  
Fem Simulation ◽  
Element Model ◽  
Control Measures ◽  
3D Fem ◽  
Whole Process ◽  
Concrete Temperature ◽  
Complex Constraints

In view of concrete structure of dam plant elbows section is complex and strong external constraints, the study of concrete temperature and stress during construction should be carried out by computer simulation. A case of plant elbow section of a sluice dam project is presented where the 3D FEM simulation of instability thermal field and stress field of the concrete structure is adopted after building the 3D finite element model, and the changes and distribution characteristics of temperature and stress during whole process of construction is obtained. The results show that, under the complex constraints condition, the concrete of plant elbow section has greater tensile stress, it can lead to structural cracking, and it is necessary to take appropriate temperature control measures.

A New Method for Improving the Stress Status of the Dam

2013 ◽  
Vol 444-445 ◽  
pp. 849-853
Author(s):  
Jian Hua Cui ◽  
Yong Feng Qi ◽  
Jie Su
Keyword(s):  
Temperature Control ◽  
Cooling Water ◽  
Control Measures ◽  
Sensitivity Analyses ◽  
Mass Concrete ◽  
Water Cooling ◽  
Concrete Gravity Dam ◽  
3D Fem ◽  
Construction Period ◽  
Operation Period

Under the action of annual change and sudden drop of air temperature, thermal induced cracking will occur in concrete dam during the operation period. For exploring the temperature control measures for crack prevention, taking a concrete gravity dam section as the research object, sensitivity analyses to the factors which affecting the water-cooling effect are conducted with 3D FEM, some significant suggestions for the water cooling are presented. The results show that, the stresses of the dam surface will decrease to a certain extent after water cooling in the operation period using the cooling water pipe which embedded during construction period, and the cracking risk of the dam will reduce. The study provides a new train of thought for the temperature control and crack prevention of the mass concrete during the operation period.

scholarly journals Temperature-stress coupling mechanism analysis of one-time pouring mass concrete

2019 ◽  
Vol 23 (3 Part A) ◽  
pp. 1615-1621 ◽  
Author(s):  
Ben-Gao Yang ◽  
Peng He ◽  
Gao-You Peng ◽  
Tong Lu
Keyword(s):  
Stress Field ◽  
Temperature Stress ◽  
Temperature Control ◽  
Damage Control ◽  
Control Measures ◽  
Effect Of Temperature ◽  
Actual Condition ◽  
Coupling Mechanism ◽  
Mass Concrete ◽  
Finite Element Software

Thermal damage control of mass concrete is the key to guarantee the quality of mass projects. Based on several engineering experiences and finite element software ANSYS, the temperature field and stress field of the typical dam section of the Tengzigou hydropower station in Sichuan province were simulated. Considering the actual materials used, cooling measures, etc., maximum tensile stress and compressive stress at different time points derived from the temperature stress field during the time of concrete maintenance were calculated, and the numerical results showed that strength increment under the given conditions was much less than the actual condition. After the concrete of the dam body of the hydro power station were poured, there was no significant temperature stress crack appeared through a long-term observation, and the project condition was in tune with the calculated expectation. The above research results are valuable to further prediction of concrete temperature in different periods, the pre-study of the effect of temperature control measures, and these could offer guidance of the adjustment of temperature control measures in the case of abnormal conditions.

Study on Thermal Stress and Temperature Cracks Control of Longlin Roller Compacted Concrete Gravity Dam

2012 ◽  
Vol 212-213 ◽  
pp. 912-916 ◽  
Author(s):  
Wen Yi Zheng ◽  
Peng Pan ◽  
Lie Ping Ye
Keyword(s):  
Temperature Control ◽  
Simulation Analysis ◽  
Control Function ◽  
Heat Of Hydration ◽  
Control Measures ◽  
Gravity Dam ◽  
Concrete Gravity Dam ◽  
Progress Control ◽  
Roller Compacted Concrete ◽  
Rational Construction

In order to guide temperature control design and construction and to guarantee the construction quality of roller compacted concrete (RCC) gravity dams in severe cold area, it is of great significance to carry out the simulation analysis of temperature and stress. The whole progress of construction and operation of Longlin RCC gravity dam in harsh climate region were simulated by using the heat of hydration analysis control function, construction stag analysis control function and the time-dependent material link of MIDAS.civil.2006. According to the construction process, the curves of temperature and the curves of stress were obtained. The locations where the crack ratio may exceed 20 were also obtained and the correct temperature control measures and the rational construction progress control system were pointed out.

scholarly journals Temperature Control Measures and Temperature Stress of Mass Concrete during Construction Period in High-Altitude Regions

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Zhenhong Wang ◽  
Li Tao ◽  
Yi Liu ◽  
Jiang Yunhui
Keyword(s):  
High Altitude ◽  
Temperature Stress ◽  
Temperature Control ◽  
Lower Layer ◽  
Temperature Drop ◽  
Control Measures ◽  
Mass Concrete ◽  
Prevention Measures ◽  
Concrete Gravity Dam ◽  
Climate Conditions

The focus on the development of China’s vast hydropower resources has shifted to Tibet and other plateau regions. These areas are high-altitude regions whose basic climatic characteristics are as follows: dry climate, significant differences in daily temperature, and strong solar radiation. If a dam is built under such special climate conditions, specific and strict temperature control and crack prevention measures should be taken. Therefore, this study explores the temperature control standards, as well as temperature control and crack prevention measures, for concrete in high-altitude regions using three-dimensional finite element methods and based on the concrete gravity dam in Tibet in combination with the characteristics of material properties that are disadvantageous to temperature control and crack prevention. The temperature drop process can be optimized in time, and the temperature drop rate can be controlled to prevent excessive scale and temperature drop rates. Moreover, the temperature gradient can be spatially optimized, and thus, the differences in foundation temperatures, upper- and lower-layer temperatures, and internal and external temperatures can also be reduced. The research shows that the recommended temperature control and crack prevention measures can effectively reduce temperature stress. This study has a significant value as a reference for similar projects in high-altitude regions.

Sign in / Sign up

Export Citation Format

Share Document