When it's late at night,
Have you ever heard the sound of marbles falling to the ground at home?
There are not so many people all over the country
I am interested in playing small marbles at night
This occasionally heard sound
The source of it is actually not simple
The "marble sound" on the ceiling at night often has nothing to do with marbles.
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The first possibility is the thermal expansion and contraction of the building. The temperature rises during the day, and the building fully absorbs heat. At night, the temperature of the gap in the middle of the building suddenly becomes lower. This time it is cold and hot, causing the concrete, cement and steel bars inside to expand and contract. Some building materials will make a crunch when they shrink.
The thermal expansion coefficients of these building materials are different, and the shrinkage speed is naturally different. The clanging sound at this time becomes quite rhythmic. These sounds are spread by solids and reach the ears of residents, and become the sound of marbles falling to the ground. Especially when it is late at night, the sound is extremely clear.
Another possibility is mold. This mold tastes a bit heavy, so I like to "eat" building materials cement. There is a pipeline outlet for electric light lines on the lower floor of the ceiling, which is suitable for mold survival and air, which is suitable for mold camping. Mold will invade the gaps in the cement along this hole, and then a hollow pipe will erode around it. After the surrounding cement is eroded to a certain extent by mold, the steel bars will bounce back and forth in the hollow pipeline, which will produce a "marble sound".
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Someone had done an experiment before and really ran upstairs to throw marbles, wanting to see how loud it would be when the marbles fell to the ground. The results show that the sound of marbles falling on the floor is almost impossible to hear downstairs, which is actually similar to the sound of other small objects falling downstairs. Even if you deliberately and vigorously hit the marbles to the ground, you need to hear them very carefully late at night.
In addition to these two reasons, the "marble sound" may also be related to another device.
The action of the water hammer causes the pipe to vibrate and make a sound. During the process of conveying water in the pipes in the room, the valve suddenly opens or closes, and the flow rate of the water will change, and it will also fluctuate greatly, resulting in a sound similar to the drop of marbles. For example, after using the toilet, or when the water pipes in the washing machine are drained or injected, the vibration sound is the most obvious when the water flow changes significantly.
In addition, there is another explanation about the "marble sound" that is that bricks are at work. Some people have found that the "marble" phenomenon often occurs in buildings and bungalows over ten years. Most of the roofs of these houses are made of porous plates, and the inner walls of the porous plates also collapse due to thermal expansion and contraction, and many small cement blocks were cracked. This sound spread through the hole grooves and perfectly disguised as the "marble sound".
It turns out that
The "marble sound" in the middle of the night
is not a supernatural event
There are not so many playful "children upstairs"
You don't have to worry about it when you hear similar sounds again
Just sleep steadily!
