Mr.Alireza hope you will get answer from the file attached herewith.  all the best..

Also, find your answer from the file attached herewith..

Thank you

Hello Alireza Rashiddel

To simulate rapid drawdown you need to know the pore pressure distribution before the drawdown begins. That is you need to do a seepage analysis of the downstream of the dam when it is full from which the top seepage line can be obtained. In the LEM (limit equilibrium method) the pore pressure on the trial slip circle need to be obtained via the usual procedure.

Subsequently the drawdown analysis will proceed in time increments stage by stage. The reservoir should be dewatered at the specified rate by reducing the reservoir level (dh) in a certain time increment. A new seepage analysis should be carried out to determine the seepage lines. Thereafter, another slope stability analysis should be conducted under the current conditions. Note that an error occurs in this method because as the soil unloads there will be an additional but small reduction of pore pressure due to soil expansion (reverse consolidation). This can be accounted for if the coefficient of reverse consolidation is known. (Cv = coefficient of consolidation).

It is very difficult you can use another software like SEEP 2D and Plaxis 2D. FLAC is very difficult and it needs to write the codes.

Best regards

Dear Mandana Bayat

Thank you for your reply but:

On 2018, I completed the project using the Fish language in FLAC software.

Please see this workshop:

https://civil808.com/shop/products/s23-26/22925/%D9%81%DB%8C%D9%84%D9%85-%D8%A2%D9%85%D9%88%D8%B2%D8%B4%DB%8C-%D8%B4%D8%A8%DB%8C%D9%87-%D8%B3%D8%A7%D8%B2%DB%8C-%D9%BE%D8%B1%D9%88%D8%B3%D9%87-%D9%85%D8%B1%D8%AD%D9%84%D9%87-%D8%A7%DB%8C-%D8%B3%D8%A7%D8%AE%D8%AA-%D8%B3%D8%AF-%D8%AE%D8%A7%DA%A9%DB%8C-%D9%88-%D8%A2%D8%A8%DA%AF%DB%8C%D8%B1%DB%8C-%D8%A7%D9%88%D9%84%DB%8C%D9%87-%D8%A2%D9%86-%D8%A8%D8%A7

I suggest learn FLAC2D-3D software !!

Warm Regards,

Rashiddel

In my idea, upstream is transient. I think that you make a model with different levels water in upstream,rapid drawdown is very difficult for modeling. The simulation is near the real.

1. The 3D analysis and estimation of transient seepage in earth dams through PLAXIS 3D software: neural network

Numerical study of Seepage for KORD-OLIYA dam and compare by using actual data

2.

Dear Mandana Bayat

Wouldn't it be better to see the workshop first before discussing it?

If I wanted to Rapid Drawdown of the earth dam in another software, I would not ask this question in Researchgate. The purpose of my project was to model in FLAC; otherwise, it could be accomplished in other software programs very easily. Additionally, using the icon does not create an engineer, but you must code and program in order to comprehend the concept of calculations and numerical analysis.