China's viaducts are full of ivy, why plant ivy? Won't it destroy the bridge?

In the long process of human development , among the four ancient civilizations, there is only one Chinese civilization left in the 21st century.

However , it is precisely because of our long-term prosperity that our country cannot keep up with the development of the Industrial Revolution. Compared with capitalism , the relatively backward and aging feudal system has shackled the minds of the rulers and caused the country to suffer. The ravages of greedy robbers .

In the last century, countless people of insight worked hard , and in the years of war, they finally defeated the crazy war criminals and ushered in socialism. After the reform and opening up, China's economic level and scientific and technological development have been greatly improved, and the people have gradually become richer. However, due to historical reasons and traditional thinking, China has always been in a poor and backward state. From backwardness to progress , from backwardness to development, after the founding of the People's Republic of China, China 's infrastructure construction has made remarkable achievements .

From 2005 to 2017, China's newly added expressway mileage exceeded 70,000 kilometers , ranking first in the world. By 2021, in addition to the third , 17th , and 18th bridges , the longest bridges in the world will be is foreign .

If you look closely , the Three Gorges Dam , the world's tallest bridge with a length of 1341.4meters , and the Beipanjiang Bridge are all landmark construction .

In 2021, those of us who live in China , especially those who take taxis , don't have to worry about traveling. After all, there are subway stations, subway stations , and taxis everywhere. If you don't have to wait too long, you can click on your mobile phone and open it. The corresponding APP taxis.

In prosperous cities, we often see bridges spanning surface highways, opening new traffic paths on top of existing roads, also known as viaducts.

A lot of creepers can often be seen on the piers of viaducts. Some people may wonder, what are the uses of creepers on viaducts? Don't they get into the cracks of the piers and damage the bottom of the viaduct?

Creeper

First, let's get to know this creeper. It is native to China and is a perennial vine of the Vitis family. In addition to its scientific name, it is also known by the names Red Silk Grass, Maple Vine, Flying Centipede, and Bundle Stone Dragon.

Creeper tends to bloom in summer with small yellow-green flowers that are sometimes overlooked.

The color of the leaves of the creeper is bright green, very bright and beautiful, and it looks very pleasing to the eye. At the same time, its leaves are alternate, just like a perfectionist, the leaves will grow in the same direction, and they are very orderly and tidy. When there is a crowded situation, one by one stays where they should be honestly, neither overlapping nor bifurcated, and the edges are large and small jagged.

Most of its leaves are wide oval, usually stem, succulent texture, 8-18cm long and 6-16cm wide. The veins on both sides of the leaf surface are mirror-looking and symmetrical, which is very in line with the preferences of "obsessive-compulsive disorder".

The climbing tiger has a strong ability to climb. There are often short tendrils on the branches. It is a sucker-like object, which is composed of several threads. It is very sticky and can only be attached to objects. These tendrils, the ivy can't climb up at all.

For example, if we look closely at a creeper, we can see that it has thin "feet" growing on its petioles, and they are not bright green like creepers, but bright red and look very delicate.

When the creeper's foot hits the wall, thin red filaments extend up to a powerful suction cup that attaches to the wall. The filaments are straight at first and then slowly bend.

If the creeper's feet are not against the wall, the filaments are discarded as non-functional until they fall off and disappear.

The creeper even bears fruit between September and October, when it produces small ball-shaped berries, mostly purple-black or bluish-black, that are often eaten by birds.

Why does this phenomenon happen to the ivy on the viaduct?

In fact, the ivy under the viaduct deliberately attached itself to the entire viaduct pier. Although this approach may seem very dangerous, it is a safe and effective way, and it can also play a role in beautifying the urban environment. In foreign countries, many cities have banned the use of creepers as green plants. Why is this happening? This is also because creepers actually have a lot of advantages, one of which is that they lower the temperature.

Creeper generally piles up walls or rocks layer by layer, densely packed with stems and leaves, and is firmly attached to it like a needle and thread for weaving.

Viaducts are generally in the form of reinforced concrete structures. Due to their high strength and ignition point, coupled with the harsh external climate environment, the concrete is prone to thermal expansion and contraction, which affects the normal use of the viaduct. Therefore, in the actual construction process, management and control should be strengthened to prevent problems such as cracks or deformation due to changes in temperature difference. In addition, attention should be paid to avoid cracking of bridges in high temperature seasons to ensure their safety and stability. In the long run, unnecessary risks may arise.

Statistics show that in summer, the pier cement columns of the viaduct can reach as high as 60 degrees Celsius.

But if a creeper is planted below, this wild grape-like plant will quickly climb up along the cement column, thereby forming a shelter like a parasol. Strictly, do not give the sun a chance to prevent the reinforced concrete from being exposed, resulting in accidents.

It turns out that walls covered in creepers are three to five degrees cooler than those exposed to sunlight without the help of reptiles.

Creeper has a good waterproof effect. Climbing up the hillside, if there is no windshield, then it will get wet, and it may even be dangerous; the third is because the creeper has a shade function. When the sun goes down, it can reflect sunlight onto the ground. Creeper is not only a sunshade to block the rain, but the umbrella has a strict protective effect on the cement column, and can also play a good role in resisting the erosion of rain.

When it rains, the rain first falls on the surface of the leaves of the creeper, and then pours down from the layer of leaves, causing little damage to the reinforced concrete of the viaduct. But, you know what? If this rainwater is collected and reused, a lot of water resources can be saved! This is the story we are going to tell today - "Sponge City". Why use a "sponge city"? So here comes the question: what if we use cement pillars instead of water for flushing?

The answer is of course yes, cement is much stronger than soil, but cement is called dripping water, which can corrode stones for a long time, so how can cement remain intact under the sun, rain and rain?

In addition, since the Industrial Revolution, with the rapid development of human science and technology, factories and other buildings have been polluted all over the world. In the past, there were no international restrictions on the emissions of these factories.

The existence of creepers can well block acid rain, "block out" the acid rain, and prevent the viaduct from being damaged.

Third, the greening effect of the creeper. The fourth is that it has a strong ornamental. Its main features are: 1. Beautiful shape; 2. Wide adaptability; 3. High ornamental value. 4. It is easy to propagate and simple to cultivate.

There are many species of ivy, and the buildings formed are different according to the terrain and topography of the area where they are located. After climbing a hill, the higher you climb, the easier it is to be crushed to death; the slower you climb, the less likely you will fall off the cliff. So creepers are very spiritual plants. Creeper flowers are very special. Its color also changes with the seasons, such as green in spring and yellow-green flowers in summer.

When the autumn is high and cool, the leaves will turn back to orange-yellow color, which is consistent with the color of autumn, and small purple-black or blue-black berries will grow, attracting birds to come for food, which is not only beautiful but also interesting. Creeper is a kind of bird that likes to eat fallen leaves very much. There are many small holes in their body, which can absorb dust and moisture in the air, thereby reducing the dust content in the air.

In addition, the creeper also has the function of protecting the wall.

Of course, it also has some shortcomings. For example, due to the needs of survival, its roots are very developed, and it will drill into the cracks of the wall and continue to deepen, so that the gaps in the wall increase day by day, the damage is more and more serious, and the collapse is very likely.

At the same time, the roots and suckers of creepers secrete acid substances that corrode rocks.

However, in actual life, the root of the creeper is only active in the underground soil, and it can't drill into the cement column at all. It is only its "feet" that climbs to the top, and the feet only have the ability to absorb, and do not have the function of expanding and growing outwards. .

Creeper feet also secrete an acid that reacts to the lime composition of the cement posts, but the reaction is actually very slow and subtle.

These small shortcomings, compared with the advantages of the ivy, are basically impossible. After all, the person who chose the ivy must have carefully analyzed and judged everything, and there is no reason to rush for success.