Hello, everyone.

This is Enta.

Today's topic is drain pipes.

I’d like to write about a common misconception among drainage drilling workers.

Well, generally speaking, rain falls from above, lol.

Water in the mountains comes from both seepage from above and inflows from deep within the mountains, but in this article, we’ll focus exclusively on water from above.

As shown above, rain falls and seeps into the ground.

 

Since we’ve installed drainage pipes, I’m sure you can imagine that the rainwater is flowing into them.

Go into the pipe and come out the other side.

That's all there is to it, but this is where the misunderstanding begins.

Many people think this way.

I think the water flows into the drainpipe from above and goes outside.

Let's start by looking at the picture on the front.

Let's say there are three drain pipes installed when viewed from the front.

If it rains and water flows into the drainpipe from above, the situation would be as follows.

It's almost as if the water has a mind of its own and is flowing straight down the drainpipe!!? lol

That's right; when the internal pressure rises, the area where the pipe is located is where the pressure is released.

So, while I can't say for sure that they won't gather there, it does seem a little too unnatural, doesn't it?

 

When water comes out,The mountain is saturatedIf we assume that this is the case, this is the most natural way for water to flow in.

Rainwater flows down to the foot of the mountain. (I'm writing about a specific part of the process.)

That rain isn't draining away and is steadily accumulating inside the mountain. (Saturated state)

Water rising from below is discharged through the drain pipe.

This is where the misunderstanding lies.

Water rises from below, enters the drain pipe, and is discharged.

 

And, as is often the case, drain pipes are usually installed with a 3- to 5-degree upward slope, right?

Actually, that works even at 0 degrees. (Although the design always specifies an angle, this is strictly theoretical.)

The worst part is, water still comes out even when it's pointing down lol

Based on the reasons stated above, water will always settle horizontally.

For example, if there is a 5-degree angle at the top, the range is from 0 to 5 degrees. This is because they are arranged diagonally. (Especially at the tips.)

Don't you think the horizontal one drains the water faster?

You might think that tilting it at an angle makes it come out faster, but it doesn't really make much difference lol

When the internal pressure is high (saturated), if the drain pipe is the only way for the water to escape, the water will inevitably try to flow out through the drain pipe.

Well, I don't really intend to argue about the design philosophy or anything at this point, but this is purely theoretical. (Does this sound like nitpicking to those who don't get it? lol)

That's why water comes out of the pipe even when it's facing down.

Well, since the standard practice for design and such is to aim for an upward trend, I don’t intend to go against that, but I do hope that design consultants might have at least a little doubt about this aspect.

 

See you later.