Dam - Science topic

3.26

What is meaning of the missing value ? Is it zero value ?

Hello, for some of them more than 40 years ago: see attachement.

Regards

Consulting a licensed dam engineer would be preferable, due to liability, etc. Wet clay would be difficult to apply and properly compact. Water release from upstream pond would be best diverted and piped or pumped around construction site. Bentonite clay is a hazardous type material that is sometimes injected to help plug leaks. It is best to follow engineering standards for type of clay, moisture of clay/clay mix, compaction frequency of lift layers, dimensions of clay core relative to dam size, etc. The potential of dam design and failure increases when engineering review is not included, increasing liability if considered negligent if civil actions occur. There are various internet papers on small dam design, construction and management. Providing a bypass channel to prevent overflow and mechanism to help lower or drain dam is desirable to help manage dam and prevent overflow during extreme flood periods. When the moisture level in the clay meets or exceeds its liquid limit, it becomes plastic and prone to failure. There are various engineering and soil material tests that test compatibility at various moisture levels and liquid limit.

Hi Haidar Hosamo thank you for comment.

i have pass step 4 and 5, when i want to validate, there is notification "there are 60 non-valid blocks in current set "model". what i have to do next?, i want to do seepage analysis, stability check up/down stream etc.

Dear all, do you know how we can model the subhorizontal drains for retaining wall drainage in PLAXIS 2D ?

GOOD QUESTION！

Hi Ilham.

It is of course an error not considering traffic loads. However, a typical distribute load will be of 10 to 20 KPa acting on the width of the road (7 to 10 m wide, normally), which is very small, when compared to the selfweight of the dam. Therefore, this load probably is often neglected for overall stability.

William F. Hansen Thank you for the advice. I will contact the author. I learned a lot from your explanation for this question and the previous question.

I assume that the foundations are made of hard and compact rock which can be modeled as an elastic material. In this case, there are almost no differences in the response of the dam (static and/or seismic). Another reason could be related to easier modeling and less computational cost.

Personally, I prefer to model also the foundation layer.

We have developed this software for OMA https://github.com/dagghe/PyOMA

It also has a GUI!

To cite this tool:

Pasca, D. P., Aloisio, A., Rosso, M. M., & Sotiropoulos, S. (2022). PyOMA and PyOMA_GUI: A Python module and software for Operational Modal Analysis. Software X, In press

Dag Pasquale Pasca Marco Martino Rosso Stefanos Sotiropoulos

Abaqus is powerful for modeling stage construction via the model-change feature (Interaction module). However, this capability is available in Abaqus Standard only (not yet available for Abaqus Explicit).

With SWAT, only data availability is the issue. If you are having high-quality data (especially DAM related data for the basin) then, you should go with the SWAT. It is very reliable and gives great results.

Chengyong Gong Thank you professor. I am still an entry level engineer. graduated from school just recently. Looking for some mentoring from fellow engineers here.

This is a typical confusion while using Seep/W at the startings. Before defining boundary conditions I recommend you align the axis to the exact elevation you have obtained from the topographical map. Then define the boundary condition by applying the head of exact elevation as that of field and assign that to the upstream face. Also, define a boundary condition with seepage face on the downstream. Then for the Flux, it's rather easy to draw the Flux line on GeoStudio 2012 than on recent, so at first, you can learn from the old version.

Hi

It is highly recommended. Calibration of sediment transport model is as important as hydrodynamic one which can make sure and prove the model works well.

Wetland ecosystem services can be assessed after the construction of dams by making a study of the biodiversity of plants and the biodiversity of animals and knowing the change that has occurred.

This is about the Santee Cooper project, South Carolina. I’m sure there is an abundance of studies / more recent. This may be helpful.

Kjerfve B. 1976. Santee-Cooper: A study of estuarine manipulations. Pp 44–56 in M. Wiley, ed. Estuarine Processes, Vol 1: Uses, Stresses and Adaptation to The Estuary Third International Estuarine Research Conference Galveston, TX. Academic Press, NY.

You can use the recently released HEC-RAS v6.0 (Beta) supports 2D sediment scour and deposition simulation.

Please find the paper, i think it will be helpful for you.

In my perspective, I think the term sensitivity analysis is more appropriate to use in mathematical models such as HecRAS, SWAT etc.

In case of AHP based overlay analysis, this is knowledge based modeling, and depends on the expert judgement.

In order to reduce the no of factors, one may use statistical techniques such as PCA or cluster analysis.

Regarding, validation in such as scenario, only one may propose various sites and let the field observations validate their suitability.

It is simply, throwing an arrow in dark but with sound scientific and rational judgement.

Thanks

Azazkhan Ibrahimkhan Pathan

Multi-Criteria Decision-Making (MCDM, also known as Multi-Criteria Decision Analysis, MCDA) refers to methods – including software – for making decisions where numerous criteria (or objectives) must be addressed concurrently in order to rank or choose between the options under consideration.

A Multi-Criteria Analysis (MCA) may be used to find and analyze policy choices by evaluating their effects, performance, impacts, and trade-offs. MCA is a systematic strategy for guiding complicated decisions based on predefined criteria and objectives.

However, Zardari et al. (2015) defined three key types of MCDM techniques, which are articulated in the form of an up-to-date classification Arslan (2017) as simple, original, and differentiated methods. Because of its simplicity and broad general application, the WSM is chosen as the best MCDM approach.

I agree with the responses! Additionally, all the factors influencing the shear key resistance should be taken into account in the calculation, in order to get high precise results and thus properly ensure the dam stability!

As said Deepak Hooda, the more closer area influence significantly. Also, it depends on seepage properties of soil and leaching with time.

That is a good question.

Dear Dileep,

As mentioned by other readers, the research topic is good, however, it quite broad in its scope and would require you have knowledge of multi-disciplinary field as it also require you to develop an earthquake ground motion estimation model.

Depends on the software and whether you have mapped all of the dams or not. I've done something similar with culverts in order to "hydro condition" the DEM. If you have GIS software like ArcGIS or QGIS you can digitize small polygons on top of where the dam is. Then attribute those polygons with the elevation of the river below the dam. Convert the polygon to a raster with the same cell size as your original DEM. In ArcMap you can run the mosaic tool, add both the new rasters and the original DEM, and then set the preference for FIRST but making sure that the new rasters are on top in terms of the order that you enter them into the mosaic tool. The general approach can also be automated if you have a shapefile of dams and the locations are accurate.

The fully coupled hydro-mechanical analysis should give flow results close to the flow only analysis. However, the stress and flow results from the fully coupled are influence each other and this should be more accurate than doing separate analyses.

The mass matrix M(p) describes the generalized mass and inertia of the system as a function of the vehicle pose. Contributions to this matrix can be determined for each rigid body by using algebraic manipulations to rearrange the kinetic co- energy (3.11) into the quadratic form (3.16), for which the mass matrix is then obvious.The mass matrix for the fuselage body is found by rearranging the energy and has the same form as that found in conventional aircraft equations of motion [1, 2]. The mass matrix is(3.19)׀׀Mp=׀׀m0I00which is a diagonal matrix with the mass and inertia tensor along the block diagonal. The mass matrix for the first linkage (i = 1, e.g. the wings) is given in (3.20), and should a second linkage (i = 2, e.g. the four-bar mechanism, tail surface, etc.) need to be modeled, the mass matrix is given in (3.21). Each mass matrix has along its block diagonal the scalar mass, the inertia relative to the fuselage center of mass, and the inertia of the linkage. Off-diagonal terms represent inertial couplings within the system. The total mass matrix of the system is a summation of the mass matrices of each rigid body.View chapterPurchase book

Models and model adjustments Alvar M. Kabe, Brian H. Sako, in Structural Dynamics Fundamentals and Advanced Applications, 2020 1.2.4 Bar finite element The mass and stiffness matrix coefficients for a uniform bar element are available from the Bernoulli-Euler beam element mass and stiffness matrices; see Eqs. (1.2-14) and (1.2-51). Since there is no coupling between the longitudinal coordinates, u1 and v1, and the lateral and rotational coordinates, u2, v2, u6, and v6, the coefficients associated with u1 and v1 are the values that yield the sought-after matrices(1.2-62)[mbar]=ρl420[1407070140][kbar]=AEl[1−1−11]View chapterPurchase book

Vibrations of structures Carl T.F. Ross BSc, PhD, DSc, CEng, FRINA, MSNAME, in Advanced Applied Finite Element Methods, 1998 8.4.4 Torque bar The mass matrix for a prismatic torque bar is now derived. From Fig. 8.3, the angle of twist ϕ is given by 📷Sign in to download full-size imageFig. 8.3.ϕ=[(1−ξ) Ξ]{ϕ1ϕ2}=[N]{ui}where ξ=x/l, but as the rotational displacement, at any point, varies with r(8.50)[m]=∫vol[N]Trρ[N]r d(vol) ϕ1ϕ2=ρIxl6[2112]ϕ1ϕ2,where Ix = 2nd polar moment of are of the cross-section of the torque bar about its centroid and in the direction of the x axis.View chapterPurchase book

Modal analysis of an undamped MDoF system Jimin He, Zhi-Fang Fu, in Modal Analysis, 2001 Example 5.4 The mass and stiffness matrices of the 4DoF system in Example 5.1 are respectively:[M]=[1000010000100001]kgand[K]=[2000−100000−10002000−100000−10002000−100000−10002000]N/mand the mode shape matrix is:[Ψ]=[0⋅37363−0⋅36180−0⋅44721−0⋅827060⋅60455−0⋅223610⋅276391⋅338210⋅604550⋅223610⋅27639−1⋅338210⋅373630⋅36180−0⋅447210⋅82706]Therefore, the modal mass matrix can be calculated as:[⋅mi.]=[Ψ]T[M][Ψ]=[1⋅0101700000⋅3618000000⋅5527900000⋅94966]According to equation (5.7), the mass-normalized mode shape matrix of the 4DoF system becomes:[Φ]=[0⋅37363−0⋅36180−0⋅44721−0⋅827060⋅60455−0⋅223610⋅276391⋅338210⋅604550⋅223610⋅27639−1⋅338210⋅373630⋅36180−0⋅447210⋅82706][1⋅0101700000⋅3618000000⋅5527900000⋅94966]−1/2=[0⋅37175−0⋅60150−0⋅60150−0⋅371750⋅60150−0⋅371750⋅371750⋅601500⋅601500⋅371750⋅37175−0⋅601500⋅371750⋅60150−0⋅601500⋅37175]This mass-normalized mode shape matrix can be used to verify equations (5.40 and 41).View chapterPurchase book

Model checks Alvar M. Kabe, Brian H. Sako, in Structural Dynamics Fundamentals and Advanced Applications, 2020 Problem 4.9 Given the mass and stiffness matrices of an unconstrained system[m]=[200020001][k]=[2−20−24−20−22]compute the circular frequencies squared, mode shapes, inertia relief matrix, and flexibility matrix, [Ge]; and then show that [Ge][m][ϕr]=[0] and that the inertia relief matrix multiplied by [m][ϕr] is also equal to a null matrix.View chapterPurchase book

Multi-degree-of-freedom systems Alvar M. Kabe, Brian H. Sako, in Structural Dynamics Fundamentals and Advanced Applications, 2020 Problem 6.1 For the given mass and stiffness matrices solve the eigenvalue problem by first inverting the mass matrix. Also, normalize the resulting mode shapes to unit modal mass. What is the relationship between the trace (sum of the diagonal elements) of [D] and the sum of the eigenvalues?[m]=[3001][k]=[4−2−24](−λ[I]+[D]){ϕ}={0}and[D]=[m]−1[k]View chapterPurchase book

CASIMIR—a human body model for the analysis of seat vibrations Alexander Siefert, Jörg Hofmann, in DHM and Posturography, 2019 4.1 Condensation of the occupied seat To integrate the occupied seat into an MBS analysis, a condensation of the system matrix of the detailed model has to be performed. In Abaqus, the substructure technique enables to condense a system to the relevant DOF. Because of the linearization of the system at the operational point, the variation of properties in the frequency range is not considered.The internal forces {I¯R} of the condensed system result from the equation of motion, see Eq. (10.3), of the defined DOF.(10.3){I¯R}=[M¯]{q¯R}+[C¯]{q˙R}+[K¯]{qR}EquationofmotionforcondensedsystemThe reduced mass matrix [M¯], the reduced damping matrix [C¯], and the reduced stiffness matrix [K¯] represent the substructure. The first step is the choice of the DOF to be considered in the substructure. This step is crucial as it defines the information handed over to the MBS calculation. In the case of a ride comfort analysis, these are the global eigenmodes relevant for the transmissibility. Further relevant points for the assessment must be considered. Accordingly, nodes of the seat structure, the seat surface, and the human body are chosen. The following list shows a general overview of the locations, which should be considered; see also Fig. 10.11: 📷Sign in to download full-size imageFigure 10.11. Exemplary nodes for generation of the substructure.•Fixation points at the seat rail•Structural locations of underframe and backrest•Rear and bottom suspension system•A-side of the upholstery cushion and backrest•Center of gravity of thighs, pelvis, lumbar spine, and torsoIn the next step, the reproduction of the dynamic properties should be checked. Accordingly, a natural frequency analysis is performed for the MBS solver, here Simpack, and for the FE solver, here Abaqus. If the nodes for the substructure are chosen correctly, the resonance frequencies and the mode shapes should correlate very well. Based on the correlation, it can be stated that the substructure reproduces the linearized properties of the detailed model very well and thus the condensation is v for the occupied seat.View chapterPurchase book

Pendulum model Timothy M. Barrows, Jeb S. Orr, in Dynamics and Simulation of Flexible Rockets, 2021 Linearized quasi-steady mass matrix for the pendulum model The above mass matrix must be recomputed at each time step. For some applications, such as a frequency domain analysis tool, this is undesirable. This section describes how to create a quasi-steady mass matrix. We can write

You raised a very important question.

Assuming your flow data is also bi-weekly, that can add to uncertainty. There may be other ways as suggested, but I would look at a variant of the water balance approach. Water input into dam minus water output from dam equals change in soil and surface water storage plus any evapotranspiration as well as deep seepage that isn’t measured at outlet. There are various models to help estimate ET. If you have detailed and much more frequent flow data, then you might be able to determine the storage of water factor during a flow generating storm preceded by low inflow period and no outflow. Collecting rainfall data probably also helpful. We would probably collect flow data at 15 minute intervals on a drainage this size, and vented transducers or unvented with barometric adjustment are fairly inexpensive, and if stable cross sections are selected, and stage discharge relationship developed, with the rain and storage capacity of the beaver dam, you would be in a good position with ET estimate to develop a spreadsheet that would help collect and present data which could be fashioned into a data driven, spreadsheet model based on the relationships and specific to the circumstances. I know, this sounds difficult. There is a difference most of the time between no data, some data and having sufficient data. As I have suggested to others at times, determine your study goals, consult a statistician to help design to meet your desired goal. It is not unusual to take a few bi-weekly samples to do a quick reconnaissance, but most hydrological simulation studies end up being quite detailed.

have you fond the answer? As I am also interested...

Please, if possible, share with us the studies focused on lanslide‘s dam failure laboratory and CFD modeling. It’s very interesting issue.

Thank you,

This link will be of use to you:

The best bet from what I could surmise would be to check to see if there is a stream gauging station, or as suggested by Dr. Kiptum, existing data from department of water. When streams or rivers are gauged, there is a stage discharge relationship developed by using a current meter or more recently in modern times a doppler meter. Some velocity data is collected with these measurements. I looked on Google Earth, and for a river this size of about 800 feet wide, a professional hydrologist or engineer, or trained specialist would be making these type measurements, often from a bridge or boat. The bridge about a mile downstream of dam may have some engineering cross sections, or flow data collections. The velocity profile will change with stage, with maximum velocities typically at bankfull stage, before the channel width spreads out onto the floodplain. Downstream, there are some added modifications for controlling flow and bank groins to help reduce bank scour and near bank stress. If you have discharge and cross section data at a location, the discharge in cfs English units divided by the cross sedtion in square feet, will give mean velocity in feet per second. But as I mentioned, velocity profiles are seldom anything close to being uniform. Often downstream of dams, the clean water effect will entrench the channel and reduce or eliminate point bars, and the former floodplain may seldom flood or become abandoned, so the bankfull indicators may be gone as the channel entrenches and stabilizes. If you cannot find data and try to measure yourself, the US Geological Survey probably has some guideline documents and as well review the safety specifics and equipment needed for conducting this type stream hydrology, engineering and morphology work. If you have access to a Doppler flow meter, I believe that might give you the velocity profile data you would want for model development.

Hello Nur,

If your sample is only comprised of rescued animals, then you won't be able to pinpoint features/attributes that distinguish them from non-rescued animals (especially if the vital traits differ by species). At best, you could look for traits that appear in a high fraction of the rescued animals, and propose that these might be salient features for survival via rescue.

Good luck with your work.

Thank you for your answer Jalaleddin Rafi

Hi,

You can use ACOLITE free software to calculate Chlorophyll-a automatically by applying different algorithms and atmospheric corrections. This is much easier than implementing equations by yourself.

Hi Patrick! I am performing a similar procedure with R26R-Confetti mice as reporter system, crossed with several Cre-ER drivers. In out case we found that the susceptibility of the pregant female to the tamoxifen and the abortive effect could depend on the strain. In fact, our other reporter mice don't seem to show the same embryo lethality or adverse effects when tamoxifen+progesteron are administered at E11.5. One thing that we were suggested to do in this case was to scale down the dose (but in our case it would be difficult to have a proper activation of the Cre in our developmental window), or try to cross the female driver with the male reporter in order to circumvent possible oversusceptibility of the reporter strain to tamoxifen.

Which kind of drivers and reporters were you using?

Hi,

Keeping the system cold reduces the resistance to electric current in the system. I would recommend you keep your transfer buffer in the fridge. So it will be cold upon use. Also, you can use a frozen cooling unit to keep the system cool.

It's better to use fresh Milli-Q water.

Best of luck,

Dear Suhail Ahmed ,

This question needs more explanation. Feel free to get in touch with me for a detailed description via:

Best regards

Well, 'Yes'. And not just the obvious spatial difficulties, it is the reliance on timing signals. The epicenter is NIST: Overview at https://www.nist.gov/news-events/news/2021/02/nist-finalizes-cybersecurity-guidance-positioning-navigation-and-timing and from there are other domain specific documents like https://www.nist.gov/news-events/news/2019/08/situational-awareness-electric-utilities-nist-publishes-cybersecurity

Behind all these is usually quite a paper trail of conference presentations, meeting transcripts, etc. from stakeholders providing input, usually referenced in the bibliographies of the documents. The exceptions are, obviously, classified content with specifics on actual incidents and unresolved current vulnerabilities.

Dear Saleh,

I think this thesis could help you.

The tool I normally use is public meetings with focus group discussions as a priority.

This report Lawrence, P. (2004) Guidelines for predicting and minimising sedimentation in small dams, Project Report. HR Wallingford Ltd available to download here:

https://eprints.hrwallingford.com/515/

This may be of help. I think means "small dams" means less than 15 m high.

This paper may also be of use:

There are many programs for this. Here is one that is free:

Thank you!

These may help

stelprdb1083097.pdf (usda.gov)

a102015.pdf (dtic.mil)

DEVELOPMENT OF RIVER FLOOD ROUTING MODEL USING NON-LINEAR MUSKINGUM EQUATION AND EXCEL TOOL 'GANetXL' on JSTOR

John

Check dams reduce erosion of the area around the highway. They can be designed also using EC 2 ON CONCRETE STRUCTURES.

Agreed fareed

no

Agreed with Dr. Hansen. Further, Landslide Susceptibility Mapping studies in parts of Reservoir area (the area falling in hilly terrain) may be carried out by professional Geologists/Geoscientists, to delineate various zones of susceptibility (say high, moderate, low) in reservoir area.

I had the same problem while modeling the dam and the source in ArcSWAT.

Finally, ArcSWAT installed on ArcMap 10.2 solved the problem.

you have to use Get data

This type of very old landslides (undated) / rock slides / glacier avalanches are also present in Hunza valley along Hunza river in Central Karakoram north Pakistan.

Regards

Ijaz

Hi everyone, I have some problems with the parameters of the CDP model for UHPC material due to lacking experiments. Could you please give me some suggestions? Thanks!

When planning for a local road constructions; The full knowledge of Geology of the areas increases the Strength; Stability & Durability of engineering projects.

Thank, dear Claudio Oggeri! I will study them, as soon as the pandemic allows me to return to my office at the university, with full internet access.

Best regards.

Hello, perhaps you can find updated applications looking at the websites of some contractors and companies, such as Liebherr, Menard, Keller, ICop, Nicholson and others relevant. Also some suggestions from the following:

https://menardoceania.com.au/wp-content/uploads/2015/02/2015-Utilisation-of-deep-groundwater-barrier-walls-using-soil-bentonite-and-biopolymer-slurries-in-geotechnical-and-environmental-applications.pdf

Slag-Cement-Bentonite Slurry Walls Shana and Evans, JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING of ASCE / JUNE 2005

Regards

What type of dam are you referring to? Earth dam, concrete/gravity dam, arch or buttresses?

Steven L Larson I believe you meant to respond to a different question

You can proceed by putting average of top width and bottom width ...

This space does not allow us to quote the history of the construction of dams.

The first is the legendary kingdom of Sheba whose splendor of their queen is famous in the Bible at the time of SOLOMON. In this kingdom, dams existed at EDRAA, ADSHMA, and near Marib, the capital. Not far from this city existed by far the most important work, the SUDD AL ARIM dam on the Dhana wadi, built around 750 BC. It consisted of an earth embankment of about 4 m high and 600 m long. It was not built at the narrowest point of the river, to avoid flooding and had on each bank of large drainage works in excellent masonry. Around 500 BC, this dam was raised to 7 m and again to 14 m in the year 325 AD. The successive elevations were probably due to the sedimentation of the reservoir which reduced the available capacity, as well as to the increase in water requirements at the rate of the increase in populations. Profiles successive works were triangles, the upstream and downstream facings being inclined at 45 °. The upstream facing was covered with masonry jointed with mortar. So for over a thousand years,

this work was the basis of agriculture and means of existence in the plain of Marib located in the east. After a first rupture in the 5th century, the dam was probably destroyed around 575.

This event is related in the Quran (Sura 34, Verses 14 and following) in the following terms:

“The inhabitants of Saba had 2 gardens crossed by a stream. We said to them: Enjoy the blessings of heaven. This valley is delicious. Be grateful ”. “They gave up worshiping the Lord. We unleashed the heaped waters of a torrent against them. Their submerged and destroyed gardens produced only bitter fruits, tamarisks and nabs ”

Dear Muhammed, there is no universal method of cleaning of the reservoirs bed. I investigated the problem in the Tereble-Rikske reservoir (Zakarpattia province in Western Ukraine) on the river Tereblia (the Tiszha river basin, the Danube). So, their method is once per 5-6 years to open down sluice and to send into the river Tereblia giant amounts of sludge and decaying remnants of vegetation. This is the reason then in modern world no one ecologist could recommend large and middle volume reservoirs with the main aim og electricity generation! For some detailes look, please, my Chapter in a monograph:

Andrey

Hi,

I would read these articles to get a better sense of what you need to do. Since many endogenous protease inhibitors already exist in serum/plasma, most proteomic studies don’t require the addition of extra inhibitors, although some proteins may be more susceptible to specific cleavage than others.

Hi Myriam,

Please have a look at this article you may find it useful.

Thanks

Ankur

Follow.

have also a look here

http://globaldamwatch.org/grand/

and here

https://datacatalog.worldbank.org/dataset/worldwide-reservoir-and-dams

Thanks for your answer, Mr. Miquel.

hi Mr. Karthigeyan

about pressure head you mean, I should take various points each line of the equipotential lines, because I have a pressure line above in an earth dam, I want to take the total uplift pressure beneath earth dam. that's means along the foundation. On the other hand, does the value of the total uplift pressure is sum or biggest result under an earth dam?

please can you explain more clearly or send me an example to understand you .

with best regards

Hello everyone, some of you may be interested in how I found the solution to my question. It was fairly easy to be honest, but I was unable to find any method of doing it in any of the provided documents, however I managed to do it with the help of an employee from Bentley Systems.

In order to extract a value for total discharge in PLAXIS 2D you need to simply define a cross-section when you are viewing the groundwater flow graph. By right clicking and defining two points on your model you will be presented with a value for total discharge. In my case the unit is m³/s/m and finding the maximum total discharge under my dam model was what I was looking for specifically.

I hope that helps readers who were struggling with computing the total discharge in PLAXIS 2D.

Mathematical modeling and regionalization of the construction of dams . I do not see a direct connection. take into account the peculiarities of hydrogeological and environmental features in the riverbed another question Akrom