Global Stability of a Dam: Difference between revisions
No edit summary |
No edit summary |
||
| (2 intermediate revisions by 2 users not shown) | |||
| Line 12: | Line 12: | ||
When a dam impounds a body of water, it will experience a load or force commonly referred to as hydrostatic pressure. A variety of other forces such as uplift pressure, earth pressure, silt pressure, wave pressure, wind pressure, ice pressure, [[seismic]] acceleration, hydrodynamic pressure, and thermal stress from ambient temperature changes can also act on the dam depending upon site conditions. Global [[stability]] refers to the ability of the dam to withstand all design [[Loading Conditions|loading conditions]] with adequate safety margin. This is a function of the geometry and material properties of the dam as well as the magnitude and combination of loads acting on the structure. | When a dam impounds a body of water, it will experience a load or force commonly referred to as hydrostatic pressure. A variety of other forces such as uplift pressure, earth pressure, silt pressure, wave pressure, wind pressure, ice pressure, [[seismic]] acceleration, hydrodynamic pressure, and thermal stress from ambient temperature changes can also act on the dam depending upon site conditions. Global [[stability]] refers to the ability of the dam to withstand all design [[Loading Conditions|loading conditions]] with adequate safety margin. This is a function of the geometry and material properties of the dam as well as the magnitude and combination of loads acting on the structure. | ||
While this is imperative for gravity-type dams, global stability must also be demonstrated for appurtenances that impound water. For example, labyrinth spillway weir walls which impound the upper-most portion of a reservoir must be stable under normal and flood loadings. Failure of such a structure would result in the uncontrolled release of a portion of the reservoir. Therefore, they should be designed to gravity dam standards to resist overturning/sliding. This may require supplemental restraint such as grouted anchors due to the relatively low mass of the structure to resist the driving forces imposed by the reservoir. | |||
==Required Data== | ==Required Data== | ||
| Line 28: | Line 30: | ||
* [[Static Analysis]] | * [[Static Analysis]] | ||
* [[Dynamic Analysis]] | * [[Dynamic Analysis]] | ||
A critical aspect of any [[engineering]] analysis is communication. There are a variety of [[structural]] analysis approaches and methodologies, and it is important to owners, consultants, and regulators that clear communication is integrated in the process. General guidance and recommendations regarding both pre- and post-modeling communication are provided on this page: [[Modeling Communication]]. | |||
==Examples== | ==Examples== | ||
| Line 34: | Line 38: | ||
==Best Practices Resources== | ==Best Practices Resources== | ||
{{Document Icon}} [[Design Standards No. 13: Embankment Dams (Ch. 13: Seismic Analysis and Design) | Design Standards No. 13: Embankment Dams (Ch. 13: Seismic Analysis and Design), USBR | {{Document Icon}} [[Design Standards No. 13: Embankment Dams (Ch. 13: Seismic Analysis and Design) | Design Standards No. 13: Embankment Dams (Ch. 13: Seismic Analysis and Design), USBR]] | ||
{{Document Icon}} [[Earthquake Design and Evaluation of Concrete Hydraulic Structures (EM 1110-2-6053) | Earthquake Design and Evaluation of Concrete Hydraulic Structures (EM 1110-2-6053), USACE | {{Document Icon}} [[Earthquake Design and Evaluation of Concrete Hydraulic Structures (EM 1110-2-6053) | Earthquake Design and Evaluation of Concrete Hydraulic Structures (EM 1110-2-6053), USACE]] | ||
{{Document Icon}} [[Stability Analysis of Concrete Structures (EM 1110-2-2100) | Stability Analysis of Concrete Structures (EM 1110-2-2100), USACE | {{Document Icon}} [[Stability Analysis of Concrete Structures (EM 1110-2-2100) | Stability Analysis of Concrete Structures (EM 1110-2-2100), USACE]] | ||
{{Document Icon}} [[Roller-Compacted Concrete (EM 1110-2-2006) | Roller-Compacted Concrete (EM 1110-2-2006), USACE | {{Document Icon}} [[Roller-Compacted Concrete (EM 1110-2-2006) | Roller-Compacted Concrete (EM 1110-2-2006), USACE]] | ||
{{Document Icon}} [[Gravity Dam Design (EM 1110-2-2200) | Gravity Dam Design (EM 1110-2-2200), USACE | {{Document Icon}} [[Gravity Dam Design (EM 1110-2-2200) | Gravity Dam Design (EM 1110-2-2200), USACE]] | ||
{{Document Icon}} [[Arch Dam Design (EM 1110-2-2201) | Arch Dam Design (EM 1110-2-2201), USACE | {{Document Icon}} [[Arch Dam Design (EM 1110-2-2201) | Arch Dam Design (EM 1110-2-2201), USACE]] | ||
{{Document Icon}} [[Sliding Stability for Concrete Structures (ETL 1110-2-256)|Sliding Stability for Concrete Structures (ETL 1110-2-256), USACE | {{Document Icon}} [[Sliding Stability for Concrete Structures (ETL 1110-2-256)|Sliding Stability for Concrete Structures (ETL 1110-2-256), USACE]] | ||
{{Document Icon}} [[Design of Small Dams | Design of Small Dams, USBR | {{Document Icon}} [[Design of Small Dams | Design of Small Dams, USBR]] | ||
==Trainings== | ==Trainings== | ||
Latest revision as of 19:51, 27 August 2024
|
| Learn more about the need to consider uplift pressure when designing a gravity structure at DamFailures.org |
When a dam impounds a body of water, it will experience a load or force commonly referred to as hydrostatic pressure. A variety of other forces such as uplift pressure, earth pressure, silt pressure, wave pressure, wind pressure, ice pressure, seismic acceleration, hydrodynamic pressure, and thermal stress from ambient temperature changes can also act on the dam depending upon site conditions. Global stability refers to the ability of the dam to withstand all design loading conditions with adequate safety margin. This is a function of the geometry and material properties of the dam as well as the magnitude and combination of loads acting on the structure.
While this is imperative for gravity-type dams, global stability must also be demonstrated for appurtenances that impound water. For example, labyrinth spillway weir walls which impound the upper-most portion of a reservoir must be stable under normal and flood loadings. Failure of such a structure would result in the uncontrolled release of a portion of the reservoir. Therefore, they should be designed to gravity dam standards to resist overturning/sliding. This may require supplemental restraint such as grouted anchors due to the relatively low mass of the structure to resist the driving forces imposed by the reservoir.
Required Data
Evaluation Criteria
Types of Analyses
A critical aspect of any engineering analysis is communication. There are a variety of structural analysis approaches and methodologies, and it is important to owners, consultants, and regulators that clear communication is integrated in the process. General guidance and recommendations regarding both pre- and post-modeling communication are provided on this page: Modeling Communication.
Examples
Learn more about the need to consider uplift pressure (DamFailures.org)
Learn from the critical oversights that led to the failure of St. Francis Dam (DamFailures.org)
Best Practices Resources
Design Standards No. 13: Embankment Dams (Ch. 13: Seismic Analysis and Design), USBR
Earthquake Design and Evaluation of Concrete Hydraulic Structures (EM 1110-2-6053), USACE
Stability Analysis of Concrete Structures (EM 1110-2-2100), USACE
Roller-Compacted Concrete (EM 1110-2-2006), USACE
Gravity Dam Design (EM 1110-2-2200), USACE
Arch Dam Design (EM 1110-2-2201), USACE
Sliding Stability for Concrete Structures (ETL 1110-2-256), USACE
Trainings
On-Demand Webinar: Rehabilitation of Concrete Dams
On-Demand Webinar: Stability Evaluations of Concrete Dams
On-Demand Webinar: Analysis of Concrete Arch Dams
On-Demand Webinar: Introduction to Concrete Gravity Dams
Citations:
Revision ID: 8040
Revision Date: 08/27/2024