Контрольно-измерительные материалы по иностранному языку. Ч.3. Сборник тестов

involves advising those who are constructing such structures. In others, the IDB may need to take direct action to guarantee that floodwater drains in such a way as to not damage these infrastructure components.

At the most basic level, the primary job of an internal drainage board is controlling water levels within a given geographic area. On a day-to-day basis, this might involve modifying existing waterways, making new waterways, or otherwise modifying an area to better handle floodwater. These boards also commonly manipulate the distribution of plants, as some can help to maintain waterways or to improve floodwater handling. In emergencies, internal drainage boards can coordinate with emergency agencies to divert water from high-risk areas. They may also take charge of efforts to clear and repair an area after a flood situation.

There are actually two dams at Aswan, not one, although most people are talking about the Aswan High Dam when they refer to the “Aswan Dam.” Together, these two dams control the flow of the Nile river through Egypt, and they are also used to generate hydroelectric power for the people of Egypt. The Aswan Dam has generated a great deal of controversy ever since it was built in the 1960s. Some people fear that the dam may be causing irreparable environmental harm, and they would like to see it removed, although this would have some severe ramifications for Egypt.

The first dam at Aswan, known as the Aswan Low Dam, was built in the late 1800s by the British, and reinforced several times. This dam was initially designed to control the annual flooding of the Nile, an important event in Egypt. For thousands of years, Egyptians have lived and farmed near the Nile, taking advantage of the annual flooding to irrigate and fertilize their fields. As the population grew, the unpredictable flooding became an issue, causing loss of life and property damage, and the British responded by damming the river, in an attempt to control the flooding.

The first Aswan Dam proved to be inadequate for the task, and in the 1950s several countries including the United States pledged to help build a

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dam further upstream. However, these countries later reneged on the deal, forcing Egypt to turn to the Soviet Union for help, and in the 1960s, construction of the Aswan High Dam began.

As a result of the construction of the Aswan High Dam, mass flooding occurred upstream on the Nile, displacing people from their homes and causing considerable damage to some priceless archaeological sites. The lake which formed behind the dam is known as Lake Nasser, named for the late Egyptian President Nasser. Egyptians felt that the upstream flooding was a reasonable price to pay in exchange for controllable seasonal floodwaters and a steady source of hydroelectric power.

Over the long term, several problems have emerged in Egypt as a result of the Aswan Dam. The capacity of Lake Nasser is shrinking due to depositions of silt behind the dam, and because the silt is not reaching the rest of Egypt, Egyptians have been forced to use chemical fertilizers to support their crops. The banks of the Nile are also undergoing severe erosion, because they are being eaten away by the Nile without being replaced by fresh silt, and the fertility of the Nile Delta has declined dramatically. Evidence also seems to suggest that salinity levels in the Mediterranean increased after the construction of the second Aswan Dam, resulting in instability of fish stocks.

An earth dam is a dam built with highly compacted earth. This dam is classified as a type of embankment dam, being built in the shape of an embankment or wedge which blocks a waterway. These dams have been built by various human societies for centuries, and they continue to be produced in some regions of the world when they appear to be suitable for the location and intended use.

Earth dams can be very cost effective to build, which makes them appealing in some regions of the world. They can be made with local materials, cutting down on the expenses involved in acquiring and transporting materials to the dam site. In addition to earth, earth dams also

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often contain rock, and may be filled with a core of rock. Clay is another building material utilized in earth dams.

The design of an earth dam may be solid and consistent all the way through, or it may include layers of material. Layered materials may create an avenue for drainage which is designed to relieve pressure in emergencies. The weight of the dam as a whole creates a tight seal which secures the bottom and sides of the dam, and the pressure of the water behind the dam can also act to seal the dam in place.

Earth dams can be a safety issue. If the earth dam is overtopped, it can erode the dam, making it weak and prone to failure. Repeated overtoppings can eventually result in a catastrophic collapse of the dam. Earth dams can also experience seepage and structural failure caused by poor engineering and planning. If an earth dam fails, the water behind it will be rapidly released, and the force of the water can be highly destructive.

An earthfill dam, like other types of dams, benefits from routine inspection and maintenance. Inspections ensure that any problems with the dam are identified in the early stages, so that they can be addressed before the dam fails. Maintenance keeps the dam in good condition, reducing the risk of a catastrophic failure which could lead to loss of life and financial losses in communities located below the dam.

Earth dams can be used in the generation of hydroelectric power, for the purpose of containing water in a reservoir to secure the water supply, and in flood control. Numerous designs can be used, and software programs designed for engineering earth dams can be utilized to test possible scenarios to confirm that the earth dam will be safe once it is finished.

An embankment is an artificial barrier that is designed to hold back water or to support a roadway, railway, or canal. These man-made mounds mainly consist of stones, rocks, and earth. Most have sloping sides, much like small hills, and they're typically longer then they are tall. They can

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come in a range of sizes; some, like those supporting creeks or irrigationditches, are small, whereas those creating stability for major canals and the ships coursing through them tend to be quite large. While these barriers no matter their size can help steady and support their surroundings, they aren’t usually immune from environmental impacts. They’re often particularly vulnerable to structural stress, for instance, and need to be regularly monitored for stability. Things like cracks and weak spots usually need to be repaired right away. When the structures fail, the communities that depend on them often suffer, sometimes very seriously [15].

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Раздел 3.3. Тексты для профилей строительно-технологического факультета

Задание 1. Переведите текст.

CEMENT: MAN’S MIRACLE MIX

One of man's oldest building materials is finding its way into a lot of new places these days. Concrete, first discovered by the Romans, is now more widely used in construction than all other materials together.

The magic ingredient that makes concrete possible is cement, about which, according to one expert, more has been learnt in the past three decades than in the preceding 2000 years. Concrete is a synthetic stone, which can be formed while soft into practically any shape the builder wants. Portland cement mixed with water is the paste that binds sand, gravel, clinker into an artificial rock that becomes harder as the years pass. Portland cement does not come from a place of that name; it was called Portland because Joseph Aspdin, the English builder who invented the first dependable, scientifically made cement about 1824, thought it resembled the rock excavated on the Isle of Portland on the Dorset Coast.

What's so new about cement after all these years? Several things. One item is "squeezed" concrete, known technically as pre-stressed concrete. By giving concrete a big squeeze after it has hardened, builders can increase its elasticity ten times, so that it will bend under a heavy load without breaking. This is important in building bridges, viaducts, and floors of large buildings.

The simplest way to pre-stress concrete is to put steel wires or bars in the concrete when it is poured.

An unusual American use of reinforced concrete is the floating highway bridge across Lake Washington. The depth of the lake made piers too expensive, so engineers built the bridge on hollow concrete pontoons

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anchored in place by steel cables. It is the longest pontoon bridge structure on earth.

Until recently, the aim of engineers was to make concrete with as few bubbles as possible. Now they have come up with a new concrete that has millions of microscopic bubbles per cubic foot. It is made by adding an agent, which foams to form the bubbles when the concrete is mixed. This concrete doesn't crack when freezing. The first "air bubble" roads were built many years ago. They have stood up under winter freezes so well that today this concrete is used for new road construction.

Another discovery is "soil cement". Several years ago road builders lacking funds found that they could mix cement with soil on the site of the road, wet it and compact it, then cover it with bitumen. The first road they built is still carrying traffic. There are miles of soil-cement secondary roads and streets today. Construction goes so fast that with modern equipment a road builder can complete a mile of soil cement road in one day.

Scientists are working on research into the behaviour of cement and concrete under all kinds of conditions. Collaborating with engineers they are developing new ways of using concrete. Cement is changing the face of the earth.

Задание 2. Сделайте презентацию текста.

ROAD CONSTRUCTION MACHINERY

Road construction equipments are important for the growth of infrastructure on a national level. Road is an essential part of an infrastructure so much so that they are considered as the arteries of a geographical territory. Good roads not only make transportation easier but also benefit the economy in a substantial way. It is the roads that provide

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connectivity between two cities and between cities and rural areas. To construct roads and highways there are many construction machineries with different mechanical principles and operations.

Most of the road construction machinery are included in heavy construction machinery. There are numerous road construction machinery or road equipment traders who deal in the manufacturing and supplying of heavy construction equipment for roads. Asphalt equipment, paving equipment, concrete equipment etc. count for essential road construction machinery. Apart from fresh machine equipments, one can also source used road construction equipments like used excavators etc. for construction purposes.

Road Equipment Traders, Manufacturers, Suppliers and

Wholesalers

We cater to the needs of all types of construction machines for roads through our vast directory of road construction machines manufacturers, suppliers and wholesalers. Send Online Enquiry for Road Construction Machineries of all types and get competitive quotes from pre verified wholesale Roads Construction Machines traders and dealers.

There are different types of soil compactors in the market these days. The most common ones being:

o Sheepsfoot rollers, which run static, having tyres in the shapes of sheep's hoof and are typically towed,

o Pneumatic-tired rollers, which use rubber tires to provide pressure on soil,

o Vibratory rollers, which are used for granular and mixed soil materials; and

o Tamping foot rollers, which have the advantages of a vibratory roller with a sheepsfoot.

The sheepsfoot roller is highly demanded for compaction of plastic soils like clay or silt. These rollers penetrate through the loose soil material and

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compact the material directly with the foot tip. Pneumatic-tired rollers compact the soil from the top of the lift downward. The principle of working of vibratory rollers is by rearranging the soil from dynamic forces produced by the drum hitting the ground. A tamping foot roller also known as pad roller has feet, or pads, compacting the soil by penetrating deep into it and tilt the soil from the bottom to the top for uniform density. All these soil rollers work in accordance to their combination of vibration speed and foot shapes, thereby compacting the soil by producing a kneading effect.

Large Versus Small Projects: Selection Tips

To select a particular type of roller depends on the job size, the type of material, lift thickness and the congestion in the work site. In case of a small sized projects, the soil material is usually found to be spread. Hence a little bit of compaction is required until density is achieved, which is followed by another lift of material until the whole process is done. In such a situation, the working mechanism of the compactor is more important than size, because a large sized roller may be sitting idle on the job site during the entire compaction process. On a larger project, for instance, a highway, dam, or runway building, the compaction process is not a single day process but a continuous one. In such a case, it is important that the compactor's size and productivity match the hauling and spreading equipment on the project. Thicker lifts or or large sized rocks fill will require the large sized rollers in order to complete the project on time.

Most contractors and reputed manufacturers recommend selecting a soil roller that matches the production of your earthmoving fleet. The basic factor is weight. The roller must be able to keep up with the pace of the project. The size of your compaction equipment depends on the factors above. For example, if you need to compact thick lifts of limestone rock for a mile-long dam, you will have to get the largest vibratory roller you can get. If you are filling utility trenches on a congested site, then a midsize tamping-foot roller is what you want. If you are building a large 20acre pad for a new shopping mall, then a sheepsfoot roller is the best

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option. Its no pint running a vibratory roller in static mode on soils or base material. On the other hand, a sheepsfoot roller always runs in static mode and uses varied manipulation and impact to achieve the desired compaction of the soil.

Automation and robotics is the hot new trend in many different industries. Businesses are looking for ways of automating repetitive, timeconsuming, and dangerous tasks to enhance efficiency and improve the safety of workers. The construction industry is no different. In fact, automation is an excellent solution for builders to increase operational efficiency and to cut down on costs.

The scope of automation in the construction industry is quite broad, extending from initial planning stages all the way to operating and maintaining the final structure. Here are five examples of automation being used in the construction industry.

Autonomous Machines on the Construction Site

Perhaps the most common example of automation in construction is the use of autonomous machines. These are essentially self-driving machines that can be used to transport materials across the work site and to haul heavy items without posing a risk to workers.

For example, machines can be fitted with robotic technology solutions and sensors that enable forklifts, diggers, trucks, and other similar equipment to operate without a driver in the cabin. By creating relevant paths, providing GPS capabilities, and programming movement of the machine itself, construction site workers can remotely operate machinery and enjoy more efficient processes.

Drones to Survey Working Areas and Employees

Drones are another useful example of construction automation, allowing for the automated monitoring of worksites without the need for active supervision. Drones can be programmed to automatically scan the working area for any potential hazards, after which signals can be sent back to a centralised control system.

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Using drones allows construction companies to conduct pre-project inspections and other important site monitoring activities.

Robotics in Concrete Works

Automation in construction has also found its way to concrete mixing. Control systems and robotics are being used to mix concrete, lay the cement, polish floors, and remove surface water. This also allows companies to prepare precast and ready-mixed concrete products that take a much shorter time to install. Automation reduces material consumption and eliminates the human error that would otherwise go into concrete works.

Another area of concrete work that is enjoying the benefits of automation is concrete floor polishing. Programmable machines are being used to polish soft concrete in both commercial and residential structures. These machines can be programmed to pour and level concrete in the right portions while avoiding obstacles near the work zone.

Demolition robots are also being used to bring down walls and to dismantle concrete slabs. This often results in lower operational costs and a safer working environment for employees.

IoT Sensors to Collect and Process Data

Sensors are the key devices that make automation possible. These devices can take real-time readings of location, temperature, pressure and other conditions. Sensors allow construction companies to automate many different machines and robots according to their preferences.

Sensors can also transmit signals to machines to trigger a specific action. For example, automation is typically achieved in welding and fabrication machines through the use of sensors. These sensors collect important environmental data that can be used to trigger a relevant action in the welding machine.

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