The multi-objective optimization method was used for shape optimization of cement sand and gravel (CSG) dams in this study. The economic efficiency, the sensitivities of maximum horizontal displacement and maximum s...The multi-objective optimization method was used for shape optimization of cement sand and gravel (CSG) dams in this study. The economic efficiency, the sensitivities of maximum horizontal displacement and maximum settlement of the dam to water level changes, the overall stability, and the overall strength security were taken into account during the optimization process. Three weight coefficient selection schemes were adopted to conduct shape optimization of a dam, and the case studies lead to the conclusion that both the upstream-and downstream dam slope ratios for the optimal cross-section equal 1:0.7, which is consistent with the empirically observed range of 1:0.6 to 1;0.8 for the upstream and downstream dam slope ratios of CSG dams. Therefore, the present study is of certain reference value for designing CSG dams.展开更多
The first author proposed the concept of the cemented material dam (CMD) in 2009. This concept was aimed at building an environmentally friendly dam in a safer and more economical way for both the dam and the area d...The first author proposed the concept of the cemented material dam (CMD) in 2009. This concept was aimed at building an environmentally friendly dam in a safer and more economical way for both the dam and the area downstream. The concept covers the cemented sand, gravel, and rock dam (CSGRD), the rockfill concrete (RFC) dam (or the cemented rockfill dam, CRD), and the cemented soil dam (CSD). This paper summarizes the concept and principles of the CMD based on studies and practices in projects around the world. It also introduces new developments in the CSGRD, CRD, and CSD.展开更多
The cement sand and gravel(CSG)dam is a new style of dam that owes the advantages both of the concrete faced rock-fill dam(CRFD)and roller compacted concrete(RCC)gravity dam,because of which it has attracted much atte...The cement sand and gravel(CSG)dam is a new style of dam that owes the advantages both of the concrete faced rock-fill dam(CRFD)and roller compacted concrete(RCC)gravity dam,because of which it has attracted much attention of experts home and abroad.At present,some researches on physic-mechanical property of CSG material and work behavior of CSG dam have been done.This papcr introduces the development and characteristics of CSG dam systematically,and summarizes the progress of the study on basic tests,constitutive relation of CSG material and numerical analysis of CSG dam,in addition,indicates research and application aspect of the dam.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 51179061)the Specialized Research Fund for the Doctoral Program of Higher Education (Grant No. 20100094110014)
文摘The multi-objective optimization method was used for shape optimization of cement sand and gravel (CSG) dams in this study. The economic efficiency, the sensitivities of maximum horizontal displacement and maximum settlement of the dam to water level changes, the overall stability, and the overall strength security were taken into account during the optimization process. Three weight coefficient selection schemes were adopted to conduct shape optimization of a dam, and the case studies lead to the conclusion that both the upstream-and downstream dam slope ratios for the optimal cross-section equal 1:0.7, which is consistent with the empirically observed range of 1:0.6 to 1;0.8 for the upstream and downstream dam slope ratios of CSG dams. Therefore, the present study is of certain reference value for designing CSG dams.
文摘The first author proposed the concept of the cemented material dam (CMD) in 2009. This concept was aimed at building an environmentally friendly dam in a safer and more economical way for both the dam and the area downstream. The concept covers the cemented sand, gravel, and rock dam (CSGRD), the rockfill concrete (RFC) dam (or the cemented rockfill dam, CRD), and the cemented soil dam (CSD). This paper summarizes the concept and principles of the CMD based on studies and practices in projects around the world. It also introduces new developments in the CSGRD, CRD, and CSD.
文摘当前国内外对胶凝砂砾石大坝(CSG Dam)渗流场的研究均局限于稳定渗流场,但由于库水位的不断波动,大坝在运行期大都处于非稳定渗流状态,保证这种新型坝在库水位变化时的安全稳定非常重要。采用有限体积法及计算流体力学中的VOF(volume of fluid, VOF)法,对CSG坝两个极端工况下的非稳定渗流场进行模拟,获得孔隙水压力、浸润面、流速及流量的演变过程,结果表明:1)CSG坝体防渗效果良好,即使在面板防渗性能降低的情况下,浸润线也处于较低的高程;2)在水位上升阶段,坝踵附近在水位上升初期渗流量会出现不稳定波动,下游节点渗流量变化起步较晚,且需要经历一个较长的时间才能达到渗流稳定;3)水位下降时,坝体浸润面呈现中间高、两边低,上游高、下游低的趋势。一部分坝内渗水会向上游排出,产生的渗透压力不利于面板的稳定,建议在坝趾处采取排水措施,引导坝内渗水排出,减少对上游面板的不利影响。
基金The presented work is financially supported by the National Natural Science Foundation of China(Grant No.51179061)Research Fund for the Doctoral Program of Higher Education(No.20100094110014).
文摘The cement sand and gravel(CSG)dam is a new style of dam that owes the advantages both of the concrete faced rock-fill dam(CRFD)and roller compacted concrete(RCC)gravity dam,because of which it has attracted much attention of experts home and abroad.At present,some researches on physic-mechanical property of CSG material and work behavior of CSG dam have been done.This papcr introduces the development and characteristics of CSG dam systematically,and summarizes the progress of the study on basic tests,constitutive relation of CSG material and numerical analysis of CSG dam,in addition,indicates research and application aspect of the dam.