Long-term deformations of rockfill dams can be related to the type of dam,the pre-compaction achieved during the construction of the dam,the history of loading events,the rheological properties of the rockfill materia...Long-term deformations of rockfill dams can be related to the type of dam,the pre-compaction achieved during the construction of the dam,the history of loading events,the rheological properties of the rockfill material used,the seepage behavior caused by defects of the sealing,the interactions of the dam building with the foundation,and the hydrothermal phenomena of the stressed rockfill material.The present paper investigates the theological propcrtics of coarse grained rockfill materials using a hypoplastic constitutive model.Particular attention is paid to wetting deformation under different deviatoric loading states and pre-compactions.To quantify the state of weathering a so-called“solid hardness”is used in the sense of a continuum description.It is shown that an appropriate modeling of wetting deformations requires a unified description of the interaction at least between the state of weathering,the stress state,the density and the rate of deformation.The results obtained from the numerical simulations are compared with available experimental data for a rockfill material used in Xiaolangdi earth dam.展开更多
With the enlargement of core rockfill dam construction scale and the improvement of construction mechanization level, the traditional manual construction quality control method is now difficult to meet the quality and...With the enlargement of core rockfill dam construction scale and the improvement of construction mechanization level, the traditional manual construction quality control method is now difficult to meet the quality and safety demands of modern dam construction, so automatic and real-time dam construction quality monitoring with high-techs is urgently needed. The paper makes theoretical research on construction quality real-time monitoring and system integration of core rockfill dam, proposes implementation method and integrated solution of construction quality real-time monitoring of core rockfill dam construction process, realizes refining, all-whether, entire-process and real-time control and analysis on key links of dam construction, and introduces the application of the construction quality real-time monitoring and system integration technology to a practical core rockfill dam project.展开更多
The conventional quality control method of core rocldill dam construction exhibit difficulty controlling compaction parameters accurately or ensuring construction quality. This is because it is easily influenced by hu...The conventional quality control method of core rocldill dam construction exhibit difficulty controlling compaction parameters accurately or ensuring construction quality. This is because it is easily influenced by human behavior or lack of adequate management. We therefore establish the timely monitoring indexes and control criteria of compaction processes by considering the characteristics and quality requirements of high core rockffll dam construction. Based on the established indexes and criteria, integrating GPS, GPRS and PDA technologies, a real-time compaction quality monitoring method is proposed. The relevant key techniques are proposed as well, including automatic collection of information and a graphic algorithm for rolling-process visualization. By the proposed method and techniques, a real-time monitoring system is provided to realize the precise automatic online entire-process monitoring of compaction parameters, including compaction pass, rolling trajectory, nmning speed of roller, vibration status and rolled pavement thickness. The application of the Nuozhadu project shows that the proposed system can control compaction parameters effectively and ensure better construction quality. Therefore, it might become a new way towards construction quality control of high core rockfill dam.展开更多
基金This work was partially supported by the National Natural Science Foundation of China(Grant No.51179059)the Fund for Young Scientists in Nanjing Hydraulic Research Institute。
文摘Long-term deformations of rockfill dams can be related to the type of dam,the pre-compaction achieved during the construction of the dam,the history of loading events,the rheological properties of the rockfill material used,the seepage behavior caused by defects of the sealing,the interactions of the dam building with the foundation,and the hydrothermal phenomena of the stressed rockfill material.The present paper investigates the theological propcrtics of coarse grained rockfill materials using a hypoplastic constitutive model.Particular attention is paid to wetting deformation under different deviatoric loading states and pre-compactions.To quantify the state of weathering a so-called“solid hardness”is used in the sense of a continuum description.It is shown that an appropriate modeling of wetting deformations requires a unified description of the interaction at least between the state of weathering,the stress state,the density and the rate of deformation.The results obtained from the numerical simulations are compared with available experimental data for a rockfill material used in Xiaolangdi earth dam.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 50525927, 50879056)
文摘With the enlargement of core rockfill dam construction scale and the improvement of construction mechanization level, the traditional manual construction quality control method is now difficult to meet the quality and safety demands of modern dam construction, so automatic and real-time dam construction quality monitoring with high-techs is urgently needed. The paper makes theoretical research on construction quality real-time monitoring and system integration of core rockfill dam, proposes implementation method and integrated solution of construction quality real-time monitoring of core rockfill dam construction process, realizes refining, all-whether, entire-process and real-time control and analysis on key links of dam construction, and introduces the application of the construction quality real-time monitoring and system integration technology to a practical core rockfill dam project.
基金supported by the National Natural Science Foundation of China (Grant Nos. 51021004, 51079096)the Program for New Century Excellent Talents in University (Grant No. NCET-08-0391)
文摘The conventional quality control method of core rocldill dam construction exhibit difficulty controlling compaction parameters accurately or ensuring construction quality. This is because it is easily influenced by human behavior or lack of adequate management. We therefore establish the timely monitoring indexes and control criteria of compaction processes by considering the characteristics and quality requirements of high core rockffll dam construction. Based on the established indexes and criteria, integrating GPS, GPRS and PDA technologies, a real-time compaction quality monitoring method is proposed. The relevant key techniques are proposed as well, including automatic collection of information and a graphic algorithm for rolling-process visualization. By the proposed method and techniques, a real-time monitoring system is provided to realize the precise automatic online entire-process monitoring of compaction parameters, including compaction pass, rolling trajectory, nmning speed of roller, vibration status and rolled pavement thickness. The application of the Nuozhadu project shows that the proposed system can control compaction parameters effectively and ensure better construction quality. Therefore, it might become a new way towards construction quality control of high core rockfill dam.
