Aswan Dam: An example for Grout Curtain Application

In my Water Resources Engineering course, it was mentioned that before building a dam the foundation must be stable. The foundation must have less deformation under high loads, must have little to no permeability and seepage, increase shearing strength, and satisfy slope stability for the side hills. But regular foundation applications do not comply with the properties stated above. This is why grouting must be used. While I was searching videos about grouting, I came across this one:

In the video, the construction of the Aswan High Dam is being mentioned. This dam is very important for Egypt because of the drought problem and irrigation is now mostly provided by this dam. Periodic floods and droughts have affected Egypt since ancient times. The dam mitigated the effects of floods, such as those in 1964, 1973, and 1988. Navigation along the river has been improved, both upstream and downstream of the dam. 

Green irrigated land along the Nile amidst the desert

The base of the dam is nearly a wile wide and is the key to dam stability. As seen in the figure below, the dam has a core that must sit on the bedrock but in the region where the Aswan Dam is placed, bedrock is under 600 feet of silt and loose rock. So the most cost and time efficient solution was to transform a slice of the riverbed with a grout curtain. The workers drilled narrow holes lined with iron pipes into the sediment. Then the grout was pumped into the holes while the pipes were going up. This process was repeated hundreds of times until a grout wall was formed under the core. 

Source: 
(Water Resources Engineering, Yanmaz A. Melih, 2018)

Storm Surges

In this post, I will be writing about storm surges. For my Coastal Management course, we were assigned to watch some videos related to storm surges. While working on the course, I said might as well create a blog post about it.

A storm surge is not directly related to rain but is related to wind, basically, the sea level rises so much that it causes extreme flooding. This is an outcome of hurricanes mostly. 

Sea level usually changes because of the gravitational rotation of the moon, sun, and earth. When in line, the forces combine to create the highest of the high tides and lowest of the low tides, which are referred to as “spring tides.” These occur every 14-15 days, during the full and new moons. When the forces are perpendicular to each other, the variation between high and low tide is at its least since the forces are pulling the water in different directions. This is referred to as a “neap tide,” and it occurs during the first and last quarters of the moon.

Another effect on the sea-level rise is the wind, where the wind transfers its momentum into the water which causes water to crash into the shoreline with high momentum. So the speed of wind would be simply equal to the speed of the water. But speed varies a lot inside a storm, intensity, direction, and size change so it is extremely difficult to measure that. 

By tracking the sea level rise and collecting the timing, extent, and magnitude data to analyze it. Some sea walls as barrier structures might help and ease the damage, as for infrastructures they should also be designed keeping in mind the maximum flooding caused by precipitation values with the storm surge flooding values. According to the Panel on Climate Change, frequency and intensity may change in the future. And as for frequency, it may be decreasing. But the intensity, which is the wind speed and rainfall amount, is most likely increasing because of greenhouse warming. 

Here is a nice video about storm surges;

About Venus

So, in my previous posts, I mentioned Mars a lot. The reason behind this is that it is the best option for becoming our second home, and also we have the technology to travel through Mars and examine the needed properties. While doing research for my blog, I came across an article about how Venus went through global warming. And it sure does sound familiar. So today, I will briefly mention Venus and why it should be a warning sign for us. 

Venus has the same mass and same mass as Earth. It has a thick atmosphere. Its atmosphere contains greenhouse gas carbon dioxide and its clouds are made up of sulfuric acid. It rotates so slow that 1 year on Earth is equal to 2 days in Venus. It is the hottest planet we know, but it is not the closest planet to the Sun, its surface temperature is 460 degrees in Celcius. The best survival rate for a robot in Venus is 2 hours. 

Heres a brief video about Venus;

Data collected at NASA's Pioneer Mission to Venus has given some insight into Venus's past climate and geology. It is suggested that Venus had a very familiar climate and geology to ours, but its seas has evaporated because of its nearness to Sun. "As a result, the planet’s early ocean evaporated, water-vapor molecules were broken apart by ultraviolet radiation, and hydrogen escaped to space. With no water left on the surface, carbon dioxide built up in the atmosphere, leading to a so-called runaway greenhouse effect that created present conditions." 

Venus 700 million years ago and now. Credit: NASA.

Sources:

4https://climate.nasa.gov/news/2475/nasa-climate-modeling-suggests-venus-may-have-been-habitable/

https://www.space.com/venus-runaway-greenhouse-effect-earth-next.html

https://solarsystem.nasa.gov/planets/venus/overview/

Mars Might Have Water Encapsulated Inside It's Crater

In my previous posts, I mentioned Jezero Crater in Mars and its similarities with Lake Salda in Turkey. In this post, I will be writing about how Mars is extremely similar to our world, Earth. In those posts, it was briefly mentioned that Mars once had water on its surface. Today Mars is extremely dry at first glance, this creates many questions such as what happened to the water on Mars's surface? Is it possible that one day Earth may have a similar change? I think with further investigations to Mars it would be possible to answer these questions.  

There are some theories about where the water went such as a study that proposes that a combination of two mechanisms – the trapping of water in minerals in the planet’s crust and the loss of water to the atmosphere – can explain the observed deuterium-to-hydrogen signal within the Martian atmosphere. So water went nowhere, again a reference to the previous post about Jezero Crater, there was a moisturized section below the hard crust of Mars. Water is trapped in the crust, now another question might arise, why is the water encapsulated? This question will be answered when we have more data about the climate of Mars. 

Scientist have examined yet another crater that has extreme similarities with an Earth lake. "They also noted the presence of a distinct set of ridges that face upward toward the crater wall, which bear a striking resemblance to ridges on Earth that formed at the edges of glaciers. " 

A topographic map shows the raised ridges (dark yellow) and low-lying areas where water ponded (white). Credit: NASA/Boatwright et al./Brown University

For this reason, I think this is a very interesting topic when considering the world's climate is getting hotter by the day. Earth is very similar to Mars geologically, maybe they had similar climates. Maybe the data and information collected by the rovers would be somewhat beneficial for Earth's climate issues and how to prevent the Earth from becoming a dry crust with little to no life on it. 

Sources:

https://www.sciencedaily.com/releases/2021/03/210316132106.htm

https://www.jpl.nasa.gov/news/new-study-challenges-long-held-theory-of-fate-of-mars-water

https://www.universetoday.com/150726/a-lake-in-a-martian-crater-was-once-filled-by-glacial-runoff/

Understanding BIM and It's Implementation in Our Jobs

This weekend, I attended a BIM Education seminar by Saniye Öktem and a Revit seminar by Tolga Arçok. For the people who are interested in this kind of stuff, I wanted to mention some highlights from the seminar. In the beginning, the image below was presented and some important differences were asked.

 

The most important thing that caught my attention was the VR headsets, this technology is being used in some firms to examine the building by simply putting on the headset and wander inside the structure. There are some pretty interesting gadgets as well and the environment looks very diverse and safe. I think this model is a great example, and with the technology we use I think this image is not so far away from reality. 

BIM is a methodology that can enable safe, efficient, and sustainable construction site the image represents. Efficiency is obtained because every discipline can work with coordination in the same model. When exporting a model or data, there is no loss or misunderstanding because while using Revit, everything is assigned prior to it being included in the schedules. I think the construction process would be much more organized and revisions would decrease is BIM methodology is used. 

There are many software's and add-ins that can be used with Revit, most outstanding ones in my opinion is firstly Advanced Steel and Robot Structural Analysis. Aside from them a program I found very impressive and advanced was TestFit. In this program, the user assigns the map location and the program generates example models. The models can be imported to Revit or another modeling program and can be later on adjusted and improved but it was pretty impressive seeing software generating a whole model. Here is a youtube video explaining;

                                                        

Here is an article about BIM Methodology:

https://www.archdaily.com/957097/bim-methodology-for-the-creation-of-smart-buildings?ad_source=search&ad_medium=search_result_all