Artificial structures: types, classification, construction, maintenance, operation and repair

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

The concept of "artificial structures" is used as a generic name for various objects that are erected at the intersection of roads with rivers, streams, other transport lines, melt and rainwater flows, deep gorges, urban areas, mountain ranges. What is all this for?

Introduction

The creation of artificial structures allows you to solve the following problems:

1. Ensures the safe movement of people over transport routes.
2. Allows stability of deformable and round slopes.
3. Regulates water flow to protect pathways from washout and waterlogging.

Examples include bridges and tunnels, pipes, viaducts, flyovers, retaining walls, pedestrian bridges, regulatory structures, galleries, siphons, mudflows, fast currents, flumes, ferry piers, filter embankments. It should be noted that there is a very clear bias towards individual representatives. So, more than ninety percent of allfacilities.

What is their purpose?

The construction of the created objects is very complex and expensive. In addition, the maintenance of artificial structures costs a considerable amount. Replacing them is hard work. Therefore, it is not surprising that they are calculated for a long service life. At the same time, an interesting pattern is observed - artificial structures that are built at different times according to various projects, meet certain specific technical requirements, and also differ in terms of their purpose, types of structures, implementation systems and bearing capacity. The combination of these factors greatly complicates the operation, repair and maintenance. Let's look at individual representatives of this group of structures.

What are they like?

And we should start here with bridges. In this case, the following objects should be mentioned:

1. The bridge itself. It is a structure along which a certain road passes through a specific obstacle. For example, railway tracks often cross water barriers in this way. Although there may be a deep gorge, the road is for another type of transport.
2. Overpass. Found at intersections of roads and railways.
3. Trestle bridge. Foundation for tracks in big cities. Overpasses are a kind of bridges, for which an infrequent and uniform arrangement of supports is provided. This is done in order to less restrict the streets and provide convenient passage / passage underthem.
4. Viaduct. These are high bridges used to cross mountain gorges, deep ravines and valleys.
5. Aqueduct. This means a bridge or overpass with a conduit made in the form of a pipe, tray, channel. It is constructed in cases where the place of liquid flow intersects with a gorge, river, road, ravine, as well as a number of other obstacles.
6. Pedestrian bridge. Created to ensure the safety of people during the transition through potentially dangerous parts of the area. For example, suburban platforms, large stations, a tunnel, a major freeway, multiple railway tracks.

This is not the whole list

There are many more types and classifications of artificial structures, which include objects of special purpose. For example, bridges should not only be strong enough to allow traffic to move freely, but also to allow safe and unobstructed passage of water as well as river/sea traffic when needed. They must be classified on the basis of design standards for their carrying capacity. Depending on the width of the crossed obstacle, design features and elevation above the ground, they can be one-, two-, three- and multi-span. We should not forget about underground structures. Culverts are a popular option. They are being built in such a way as to meet the current demand for supplies, as well as taking into account the development in the next 15-20 years.

About tunnels

Very often they are laid in mountainous areas. This is done in order to avoid numerous detours, the development of deep recesses, and for other similar reasons. Rock is removed along a predetermined path. The resulting development is fixed with concrete, stone, metal tubing. When carrying out tunnel work, there are two main ways of working:

1. Temporary lining is fixed in rocky soils.
2. Tuning shield in use.

Created underground structures according to their purpose are divided into road, rail, subways, hydraulic engineering, mining, utilities and a number of others. Often they are equipped not only in mountainous areas, but also under the riverbed (the combination of these factors is not excluded). As a rule, it is assumed that the longitudinal profile in one or both directions should not have a slope of more than 3‰. Although there are exceptions. In addition, additional requirements for the structures being created may be introduced. For example, if the tunnel is planned to be located in a curve, then the radius for it should be at least 600 meters. When erecting objects whose length will be 1000 m or more, it is necessary to provide artificial ventilation (if it is planned to use transport on steam / diesel traction). For tunnels, a concrete finish is provided, iron inserts and structures are often used. If you have to create an object in difficult hydrogeological conditions, then metal is used for decoration.

Other artificial structures

The list can be very long. This is both an embankment, which is used as an integral part when laying a road, and a dam. It should be noted that it is very common to consider the concept of "artificial structures" from the standpoint of referring to them everything that a person has done. This point of view has the right to exist. But basically they mean a limited list of objects. So, a dam with a road at the very top is considered an artificial structure. Although it is very problematic to hear the same definition in relation to a private house. Although both of them were built by people and, in fact, are artificial structures.

About construction

This process is not much different from the construction of ordinary buildings. Although it is necessary to take into account certain features. For example, if a bridge is being built across a river, then it should be borne in mind that over time it can wash away the supporting structures. And this will increase the likelihood of collapse. Therefore, it is necessary to build a structure in such a way that it has a certain margin of safety. But this is far from the only point to be taken into account. For example, bridges and tunnels may need to be repaired in the future. And at the same time, it is not permissible to close the object due to certain reasons. In this case, it is necessary to provide for the possibility of performing the necessary actions without interrupting the main functional purpose of the object. The construction of artificial structures must also comply with applicable codes and regulations.

Aboutoperation

It is not enough to build something. It is also necessary to adequately use the object and prevent the development of problems. Suppose there is a bridge over a river. What can be said about exploitation? First of all, it is necessary to establish a clear limit on the loads. For example, if an object is designed to withstand 100 tons at the same time, then it should not be very long. In addition, as a rule, the load at a certain point is very relevant here. In other words, there may be a restriction on the weight of vehicles that cross the object. It is not uncommon for a river bridge to have a weight ceiling for trucks that want to cross it. For example, 20 tons. Sometimes even their movement is generally prohibited, because the object is intended only for cars. The question is to what extent such restrictions are respected. After all, if a bridge was built for cars, and the passage of freight transport was prohibited, and at the same time the truck was loaded to capacity (for example, 30 tons), then this could end in an accident.

About the content

The best problem is the one that was prevented in time. Of course, you can wait until the very last moment, then to catch yourself and overhaul the situation, carrying out expensive repairs. But an object can last much longer if it is simply given enough time for maintenance. For example, we have a bridge over a gorge made of concrete. Maintenance involves periodic inspection and eliminationproblems until they become widespread. For example: there was a crack. If it is qualitatively and quickly covered over, then a year or a few you can be calm. But if you miss the moment, wait for the autumn rains and winter frosts, then in the spring the object will begin to spread. And there will be not a small crack, but a gaping hole. Therefore, content is very important when it comes to durability.

About renovation

If it was not possible to protect from negative factors, they have too much destructive power (earthquake) or the object simply crumbles from old age, then it is necessary to restore it. Repairs can be either small (sealing individual cracks) or major. The first option is cheaper, although it needs to be done more often. Overhaul can significantly extend the service life. Although it costs a lot of money. Let's consider a small example. There are artificial structures on the roads - bridges. There was a small crack. If it was repaired right away (even if it is processed once a year - in the spring), then in ten years the bridge will still be usable. Although, perhaps, its appearance will not be the best. If the problems are ignored, then, it is quite likely that in ten years it will be possible to use this bridge only after a major overhaul and significant infusions of money.

Conclusion

So we looked at what artificial structures are, what they are, whatfeatures of their construction, operation, maintenance and repair. Of course, the information provided is not enough to learn how to design and build such objects on your own. But you can understand the subject of the article and support a thematic conversation.