Why is the manhole cover on the road round

1.The hole under the lid is round, as the cylindrical shape best withstands the pressure of the surrounding land. Moreover, sewer access holes meant that there was enough space for one person to pass through, and the cross-section of a person climbing down a ladder was basically round.

So the round shape naturally becomes the shape of the sewer access hole. The round manhole cover is only to cover the circular opening.

2.Regarding the problem of the manhole cover circle, it can be traced back to France in the 13th century, when France was building Paris, considering the problem of building sewers, some people proposed to rebuild the cellar as a sewer, because the French winemaking was every household at that time, almost every family had a winemaking cellar, because there was a round hole in the ground for transporting the cellar of winemaking oak barrels, in order to avoid danger, these caves used round discus as manhole covers. Until the Roman Empire used French sewer technology in the construction of the city of Rome, major cities around the world used Roman sewer technology.

3.In fact, sewer covers are also square and rectangular.

4.Because the sewer is round, the manhole cover must be round.

Because the diameter of the circle is the same, even if it is turned over, the manhole cover will not fall.

The manhole cover is so heavy, and the round one is easy to transport. Just get on the roll.

The same iron sheet is made of the largest circular area, in other words, the most economical iron sheet of the circle.

The reasons why the manhole cover is designed to be round: 1. It is not easy to fall; 2. It is not easy to be damaged; 3. Easy to handle and move; 4. Reduce the occurrence of hazards.

Take a closer look, in life, we see that the manhole covers are designed to be round, why is this? Let me explain it to you.

01 Not easy to fall: the biggest feature of the circle is that the distance from the center to each side is to think, when the round manhole cover is placed at the wellhead, it can be completely overlapped, and the manhole cover will not fall to the bottom of the well. If the manhole cover is rectangular or triangular, the manhole cover and the inlet cannot coincide, resulting in the manhole cover falling easily.

02 Not susceptible to damage: The force on the entire surface of the circle is equal, and the gravitational force will be greater. When the wheels run over, the manhole cover is still flat. If it is a polygon with a shape, it is not only easy to warp and cause safety accidents, but also cause wear and tear to the edges and corners.

03 Easy to carry and move: The round manhole cover is easy to handle. Since the manhole cover is a heavy large iron block, if the manhole cover is damaged or needs to be replaced, the maintenance worker only needs to roll the manhole cover to move it to the side, which is very labor-saving and more convenient.

04 Reduce the occurrence of hazards: The round manhole cover causes the sewer mouth to be round, which can reduce the possibility of pedestrians accidentally falling down after the sewer cover is stolen, and can reduce the probability of danger.

05 The circular manhole cover setting is obtained after a series of comparisons and measurements, and the circular manhole cover has the largest footprint and is also the most material-saving.

Because the force is most uniform in the circle. It can better disperse and transmit the pressure, and it is not easy to cause chipping and collapse, so in terms of durability, it is better to have a round manhole cover. Moreover, the round manhole cover can ensure that the size of any side of the manhole cover will not be less than the size of the wellhead, and also avoid the situation of the manhole cover falling.

In the city standard and reputation, the weight of the drainage manhole cover is as high as tens of kilograms, and it takes at least a few adult men to carry it. The round manhole cover is easy to transport and can be transported away when rolled up.

Extended Materials. There will be a lot of underground pipelines in urban construction, such as sewers, underground gas pipelines, water pipelines, power pipelines, communication pipelines, national defense pipelines, etc., these pipelines must have an outlet to the ground every other section, and this section from the pipeline to the ground is called a manhole, and the manhole mouth is usually flush with the ground, so a cover is needed to cover the cover of the manhole, which is called a manhole cover. Manhole covers are usually made of reinforced concrete, metal, reinforced plastic and other materials, and the shape is mainly round and square.

On the manhole cover, it is generally necessary to indicate the purpose of the underground pipeline and the custody unit and other information. In April 2020, the Supreme People's Court, the Supreme People's Procuratorate, and the Ministry of Public Security jointly issued the Guiding Opinions on Handling Criminal Cases Involving Manhole Covers, which stipulates that theft and destruction of manhole covers can be convicted and punished as intentional injury and intentional homicide in accordance with the law.

Manhole covers are generally divided into round and square. Different shapes are used in different situations.

In the urban road administration, the circle is generally used, because the circular manhole cover is not easy to tilt, which can better protect the safety of pedestrians and vehicles.

In the countryside and cable wells, the square shape is generally used, which can better prevent the entry of liquids such as rainwater.

Reasons: 1. The force of the circle is evenly dispersed, relative to other shapes. Round manhole covers are more compressive resistant.

2. The circular manhole cover is not easy to tilt, which can better protect the safety of pedestrians and vehicles.

3. In a flat figure of the same area, the circumference of the circle is the smallest. The round shape of the manhole cover ensures that the material is used most economically with the same amount of water flow, or the water flow is the most abundant when the amount of material is used.

4. The distance from any side to the center of the circle is equal, while for other shapes such as a square, the distance from the four endpoints to the center is longer than the distance from the four sides to the center. The use of a round shape can make the manhole cover evenly stressed on the ground, and it is not easy to fall into the well.

Why are manhole covers round? 1.The manhole cover is not round, in fact, there are many square manhole covers, but everyone is used to seeing the manhole cover on the road, and the manhole cover on the road surface is indeed relatively round.

2.Why is the manhole cover round before taking it? The fundamental starting point is its shape, and since the manhole cover is round, the manhole cover is round.

3.If it is a rainwater well (which does not contain water, the water is seamed and can flow water out of the manhole cover, square), or an artesian sewage pipe well, it is round, because the round well can receive horizontal pipes in any direction. 4.

Considering the strength of the force and other issues, the same size of manhole cover can be made into a round manhole cover, to achieve the most cost-saving. 5. Some people explained: Because the Chinese have a saying called the heaven is round, so in the sewer, the manhole cover is the sky, and the sky is the circle.

Actually, this statement is more abstract, but it is not unreasonable. It is also said that no matter how the manhole cover turns, it is round, and it will not fall down easily because it is narrow. Less material can be used in the same area.

At the same time, the sewer mouth is round, which can easily reduce the probability of irregular objects such as bicycles, stones and other objects falling after the sewer is stolen. In fact, the round cover can really reduce the possibility of pedestrians accidentally falling after the sewer cover is stolen, and can reduce the possibility of dangerous outbreaks. There is also a saying, which is also interesting, that because a woman's eyes are round, the sewer mouth is also round, which can reduce the eye tiredness and physical fatigue caused by the uneven force of the eyes due to seeing other objects, thus helping us to reduce the possibility of falling into the sewer.

All in all, the manhole cover is round, which has many benefits, and it is a more correct design for the troublemaker, because if it is square or round, it is easy for us to fall into the basement. The round manhole cover can reduce the occurrence of such events. In fact, the most amazing thing is that some science and engineering students say that other shapes, such as triangular manhole covers, are really easy to fall down physically.

The reasons are as follows: 1. Because the sewer sometimes needs to be manually dredged, the area of the sewer is required to be as large as possible. In geometric figures such as square, triangle, circle, etc., the area of the circle is the largest when their circumference is equal.

At the same time, the circular shape conforms to the cross-section of the human body, making it easy for workers to enter and exit.

2. The side of the triangle or square is composed of straight line segments, and the corners formed are sharp, which can easily cause injury when encountering them during repair. The edge of the circle is an arc, so this problem does not occur. Finally, the arched structure effectively resists the pressure of the land in all directions.

3. If it is round, as long as the diameter of the manhole cover is a little larger than the sewer, the manhole cover will not fall. And the rectangular triangular manhole cover, rotated at an angle, may fall.

4. Stress consideration. Imagine if the cover of the sewer is square or other angular shape, when the impact load of the wheel acts on it, the edges and corners are very easy to damage. The round manhole cover can withstand loads from uncertain directions.

1. The lid is round, so it fits into the ground.

2. Because the diameter of each circle is equal, and the other shapes will always have the longest inner diameter.

3. Because the circumference of the circle is small, the area is large; Because the circle has 4 corners removed, the cost can be saved to the greatest extent.

4. The round manhole cover can be moved by one person, because it can roll on the ground, and the round cover can be rolled when it is replaced.

5. The wellhead can be directly covered from any angle, and the square must be adjusted to the same angle with the wellhead; A round manhole cover does not have to rotate its position in order to be erected on the wellhead.

6. From the perspective of mechanics, the round hand is relatively uniform, there is no relative stress concentration area, and it is not easy to be damaged; From a mechanical point of view, the force between the circular manhole cover and the support point is uniform, while the force point of the square or rectangular manhole cover is close to the force application point.