東華大學圖書館 |

語系: 繁體中文

說明(常見問題)

回圖書館首頁

手機版館藏查詢

登入

回首頁

切換: 標籤 | MARC模式 | ISBD

Development of Deformation-Based Lim...

Khalilzad, Mahdi.

FindBook

Google Book

Amazon

博客來

Development of Deformation-Based Limit States for Reliability Assessment of Flood Protection Earth Dams and Levees.

紀錄類型:	書目-語言資料,印刷品 : Monograph/item
正題名/作者:	Development of Deformation-Based Limit States for Reliability Assessment of Flood Protection Earth Dams and Levees./
作者:	Khalilzad, Mahdi.
面頁冊數:	148 p.
附註:	Source: Dissertation Abstracts International, Volume: 75-03(E), Section: B.
Contained By:	Dissertation Abstracts International75-03B(E).
標題:	Engineering, Civil. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3575764
ISBN:	9781303547454

Development of Deformation-Based Limit States for Reliability Assessment of Flood Protection Earth Dams and Levees.
Khalilzad, Mahdi.

Development of Deformation-Based Limit States for Reliability Assessment of Flood Protection Earth Dams and Levees. - 148 p.

Source: Dissertation Abstracts International, Volume: 75-03(E), Section: B.

Thesis (Ph.D.)--North Carolina State University, 2013.

Traditional design approaches based on the concept of factor of safety do not provide a complete indicator of level of safety pertinent to earth structures given uncertainties in loading, soil properties, and changes in geometry that can take place with time. Thus, there has been a tendency to utilize probabilistic analysis in addition to conventional design methods. Work is presented herein to introduce performance limit states and incorporate them into probabilistic analysis, for water holding embankments and flood protection structures. Coupled flow/deformation analysis is employed in the numerical analyses to capture the interdependency of under-seepage and through-seepage with deformation associated with the development of plastic zones and shear bands. Limit states were defined in terms of deformations that correspond to levels of performance or extent of damage in the embankment.

ISBN: 9781303547454Subjects--Topical Terms:

783781
Engineering, Civil.

Development of Deformation-Based Limit States for Reliability Assessment of Flood Protection Earth Dams and Levees.
LDR:04435nam a2200325 4500 001 1958950
005 20140512081856.5
008 150210s2013 ||||||||||||||||| ||eng d
020 $a 9781303547454
035 $a (MiAaPQ)AAI3575764
035 $a AAI3575764
040 $a MiAaPQ $c MiAaPQ
100 1 $a Khalilzad, Mahdi. $3 2094205
245 1 0 $a Development of Deformation-Based Limit States for Reliability Assessment of Flood Protection Earth Dams and Levees.
300 $a 148 p.
500 $a Source: Dissertation Abstracts International, Volume: 75-03(E), Section: B.
500 $a Adviser: Mohammed Gabr.
502 $a Thesis (Ph.D.)--North Carolina State University, 2013.
520 $a Traditional design approaches based on the concept of factor of safety do not provide a complete indicator of level of safety pertinent to earth structures given uncertainties in loading, soil properties, and changes in geometry that can take place with time. Thus, there has been a tendency to utilize probabilistic analysis in addition to conventional design methods. Work is presented herein to introduce performance limit states and incorporate them into probabilistic analysis, for water holding embankments and flood protection structures. Coupled flow/deformation analysis is employed in the numerical analyses to capture the interdependency of under-seepage and through-seepage with deformation associated with the development of plastic zones and shear bands. Limit states were defined in terms of deformations that correspond to levels of performance or extent of damage in the embankment.
520 $a The effect of various parameters on the flow and deformation response of embankment dams and the corresponding performance limit states are also investigated in this study. The parameters are pertinent to the geometry of dams, and applied loads in terms of intensity, duration, and cycles of loading and unloading which are equivalent to the rising and falling of water level in the reservoir. In addition, the effects of woody vegetation on soil hydraulic conductivity and the related probability of exceeding deformation-based performance limit states are investigated in this study.
520 $a Finally, the results of a series of numerical analyses simulating remedial measures conducted on embankment dams in order to mitigate the hazard. Three remedial measures including constructing a berm at the toe, constructing drainage system within the toe area, and adding an impermeable curtain from the crest extending to three different depths are investigated.
520 $a The analysis showed as the water level increased in the reservoir, the probability of exceeding each limit state increased and the target deformation was changed to the next limit state. It is shown that in a larger embankment model, the shear zone propagates deeper for failure to occur. The time to exceed LS I, II and III increases as the size of an embankment model become larger. For example, failure occurs after 4.6 days in the model with a size factor of 0.1 compared to 12 days for a model with a size factor of 0.2. This is mainly because the saturation front reaches the critical level in less time in a small dam, considering that the hydraulic conductivities are the same. After two weeks of water rising in the reservoir and sustained at the maximum pool level, the magnitudes of horizontal deformations at toe are 0.16m, 0.08m, and 0.048m for embankment models with side slopes of 1:2.5, 1:3, and 1:4, respectively. The analyses demonstrated the importance of accounting for the storm loading history when assessing the stability of the flood protection earth structures under future flood events.
520 $a Even though the levee case used in this study (Elkhorn) was in a marginal condition of stability based on limit equilibrium analysis, the probability of exceeding LS III after 10 days of a sustained high water level was 2%. This probability, however, increased over time to 37% and 72% after 20 and 30 days of sustained water loading, respectively, which signifies the importance of considering the transient nature of hydraulic loading in making condition assessments after a storm event.
590 $a School code: 0155.
650 4 $a Engineering, Civil. $3 783781
650 4 $a Geotechnology. $3 1018558
690 $a 0543
690 $a 0428
710 2 $a North Carolina State University. $b Civil, Construction and Environmental Engineering. $3 2094206
773 0 $t Dissertation Abstracts International $g 75-03B(E).
790 $a 0155
791 $a Ph.D.
792 $a 2013
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3575764