Loading and unloading works. Accounting features
To ensure safe working conditions during loading and unloading operations, it is necessary, first of all, to mechanize labor-intensive processes as much as possible by equipping all unloading points with auxiliary load-lifting devices and devices.
Loading and unloading operations are carried out in accordance with GOST 12.3.009-76 * and the requirements of SNiP Sh-4-80, the rules for the construction and safe operation of cranes approved by the USSR Gosgortekhnadzor.
It is also necessary to comply with GOST 12.3.020-80 and departmental rules.
Materials are loaded and unloaded at equipped sites or points that are systematically cleaned from debris, dirt, and in winter from snow and ice. Passages and workplaces are sprinkled with sand or slag. The grounds are well lit at night.
Loading and unloading operations are carried out with the help of cranes, loaders and small-scale mechanization. The mechanized way of conducting work is mandatory when the weight of goods is more than 50 kg, as well as when lifting goods to a height of more than 3 m. As a rule, it is necessary to load and unload powdered materials (cement, lime, gypsum) by mechanized way. With a small amount of dusty materials, in exceptional cases it is allowed to work manually, but always in dust-proof clothing, canvas gloves, respirators and dust-proof goggles. It is strictly forbidden to unload cement manually at a temperature of + 40 °C and above.
During loading of prefabricated reinforced concrete structures, they are cleaned of snow, ice, soil, and, if necessary, the mounting loops are straightened.
All loading and unloading operations and the movement of goods should be carried out under the guidance of an administrative and technical officer, who is obliged to instruct the loaders and train them in safe working methods, as well as provide them with serviceable mechanisms and devices. All workers entering construction organizations as loaders are trained for three months in safe working methods according to a 6 ... 8-hour program; those who received positive evaluations are issued certificates for the right to conduct loading and unloading operations. The loader performs only the work that is written in his outfit.
Loading and unloading operations are provided with special equipment and tools that meet the safety requirements of their production. During the performance of such work using railway or road transport, it is necessary to comply with the Safety Rules and Industrial Sanitation for Loading and Unloading Works in Railway Transport, approved by the Ministry of Railways, and the Safety Rules for Road Transport Enterprises.
When supplying the composition to the warehouse access roads, the speed should not exceed 10 km/h. Platforms and wagons standing on the ways of loading and unloading must be coupled, braked and secured with brake shoes or pads. The presence of people on the railway tracks is prohibited.
It is necessary to open gondola car hatches, car doors and platform sides with special levers, which ensures that workers are outside the zone of possible cargo drop, hatch side. It is not allowed to be in a gondola car with open hatches when unloading loose and small-piece materials.
It is allowed to start work only after the completion of maneuvers and fixing the wagons in place with brake shoes. When opening or closing the door of the car, one should be behind its canvas in order to avoid injury from the load. When opening the side of the platform, workers should stand at its ends. Leaving the board closed on one hook is strictly prohibited. For the passage of carts and the transition of loaders from car to car, bridges 1 m wide are used, made of boards 0.05 m thick, fastened from below with iron or wooden planks every 0.5 m. To secure the door rail of the car, the bridges are equipped with hooks.
Loading and unloading operations use sleds, rolling boards, stretchers and portable ladders. They are made from healthy wood, and the longitudinal bars are made from solid material.
On the ropes used in loading and unloading operations, there must be tags indicating the permissible load. Use of faulty rigging, tools and fixtures is prohibited.
Loading and unloading bags, boxes, barrels. When unloading goods in bags (for example, cement), it is allowed to stack them in height in six rows. But if it is necessary higher, then after the sixth row they make a gasket from the boards. It is allowed to lift the load above the seventh row only along the gangways with transverse strips stuffed on them, on the 10th row - with the help of a replacement worker. Cargoes in wagons or warehouses should be stacked in stable piles.
During the loading and unloading of barrels, drums, roundwood, pipes, slopes and slopes are used, which are made of hardwood with a diameter of at least 150 mm at a thin end, 4 ... 6 m long. Hooks made of strip steel are lightly attached to the upper ends not less than 15 mm thick; the lower ends of the slightly wedge-shaped form should be bound with metal. Paired slopes and slopes are fastened together with two or three transverse ties.
In most cases, rolling-barrel cargoes weighing up to 35 kg are unloaded and loaded manually by rolling if the floors of the car and the warehouse are at the same level, and by sleds with the help of ropes if the floors of the car and the warehouse are at different levels.
In wagons, loads are stacked in rows with boards laid. Barrels with liquid cargoes are placed with the stopper up.
Workers are prohibited from carrying rolling-drum loads on their backs, regardless of their weight, and being in front of the rolled load. The place of workers is on the sides of the transported cargo. In order to avoid injuring hands on objects that are in the path of the rolled load, it is forbidden to roll it by pushing it over the edges. Acids and other cargoes are allowed to be unloaded into special warehouses, the floor of which is on the same level as the wagon floor. The place of work must have water for immediate washing of the place burned by acid or alkali. If a container with acid or a caustic substance breaks during loading and unloading operations, workers in gas masks neutralize them with milk of lime, and this place is sprinkled with sand and the mixture is carefully removed with a shovel.
Loading and unloading of stone materials. Stones weighing up to 50 kg are carried by stretchers or transported in wheelbarrows. Large stones are loaded and unloaded by cranes and other mechanical devices. When unloading heavy stones from wagons or platforms, it is forbidden to push them with your hands. You should use crowbars, pushing the load along the ladder or skating rink.
Unloading timber. When unloading logs from the wagons, it is necessary to adhere to the following sequence: the racks on the side opposite to the unloading front are supported by levers, after which the upper lashing is cut at all these racks, the middle lashing is cut off from the side of unloading at the middle racks, they are removed and replaced with racks 1.5 long m; install two pairs of logs from the unloading side, one pair - on the unloaded logs, and the second - on the platform; cut down the two remaining racks from the unloading side to the level of the second row of logs from the top; the upper row of logs is unloaded, for which two workers on the platform, with the help of crowbars, with coordinated simultaneous movements, dump log after log onto the bed. Each log is dropped after the previous one has been removed from the bed and the worker below has given a prearranged signal.
In some cases, logs are transported on platforms without spacers, then they are unloaded as follows. From the unloading side, open the board of the platform and set it down, cut one extreme rack and cut off the middle wire tie. The end of the cut off rack is selected from the rack socket of the platform and replaced with a special rack, fastened with a light linkage to the opposite one. After replacing the second extreme rack in the same way and removing the middle ones, the safety cups are opened, then the workers on the side of the platform, with the help of ropes tied to the cup levers, throw back the guards, and the logs fall apart under the pressure of the stack.
When unloading lumber, the rules of safe work are also strictly observed. Before loading, care must be taken to ensure that the end posts on both sides of the platform are supported by support levers, after which the middle one is removed and the end posts are cut off by about half a meter. Having unloaded part of the platform, the props-levers are moved lower and the extreme racks are cut off again. And so on until the platform is completely unloaded. To avoid the collapse of the cargo, unloading should be done in horizontal rows.
Containers, roller tables, electric cars and battery forklifts. In order to ensure the safety of loading and unloading operations, it is forbidden to place loaded or empty containers in two tiers on an inclined plane, as well as to lift them with a crane with a grip less than four ends. Inclined and spiral descents for safety purposes are fenced from the sides along the entire length to exclude the possibility of the load falling out.
When operating battery forklifts and electric cars, it is forbidden to smoke and light a fire near the charging batteries, touch the bare current-carrying parts. When lifting or lowering the load, the driver must carefully inspect the place of unloading and follow the rules of the traffic instructions. The paths of electric vehicles and forklifts must always be lit.
Road transport is widely used for the transportation of goods. Each vehicle must be technically inspected before being released to work. Only technically sound cars equipped with traffic police documents can be allowed to work.
When laying bulk cargo in the body of a car or trailer, it must be placed in the body no higher than the sides, piece, laid above the level of the sides, should be tied with strong ropes or soft ropes.
When transporting equipment and other goods, accompanied by loaders, it is necessary to take measures to prevent people from falling from the body. At the same time, materials are evenly placed over the entire area of the car body, and piece goods are placed in order to exclude the possibility of their arbitrary displacement along the way. A trailer intended for the carriage of long loads is equipped with a turning device (turnstile), the loading height of which must be at the same level as the floor of the vehicle.
When unloading on embankments, as well as when backfilling excavations, dump trucks should be installed no closer than 1 m from the edge of the natural slope. Loading from overpasses that do not have protective (shock) bars is prohibited. Bulk loading of goods into flatbed vehicles is allowed only up to the level of the sides of the body.
Cars carrying compressed gas cylinders are equipped with special racks with felt-covered recesses along the diameter of the cylinders.
Explosive, poisonous, flammable and other dangerous goods are transported in accordance with the instructions agreed in the prescribed manner and by the supervisory authorities.
The raised bodies of dump trucks are cleaned by workers, being on the ground, with scrapers or shovels with an elongated handle.
It is not allowed to transport long loads on dump trucks, including those with trailers.
Moving goods manually. When manually loading and unloading timber, it is necessary to use strong sleds, winches, crowbars and other devices. It is not recommended to load and unload rolling loads manually. However, in construction organizations, in exceptional cases, these works are allowed to be carried out manually. At the same time, workers standing on the ground or platform should be on the side of the load being lifted or lowered, which must be supported by a rope from the opposite side. It is not allowed to stand behind the load to be lifted or in front of the load to be lowered.
Beams, rails, pipes and other long materials are carried only with special grippers in the form of steel tongs. It is forbidden to carry them on the handles of shovels and crowbars. The maximum weight of the load that can be carried on a horizontal surface, kg:
For men over 18 .............. 50
For women » » ........... 15
For teenagers aged 16 to 18..... 16.6
The same, female .............. 10.25
Lifting loads by hand to a height of more than 3 m is not allowed.
Acids, caustics are unloaded and loaded only in glass containers placed in wicker baskets. It is forbidden to carry acid bottles, gas cylinders on the back or shoulders. The latter are transported only in trolleys or carried manually by two workers in wicker baskets on specially equipped stretchers.
Storage of materials. Flammable and combustible materials must be stored in special rooms in closed containers (barrels, cans) with hermetically sealed lids or plugs.
Toxic substances are stored in separate rooms, remote from housing, as well as from places where any work is carried out. Their storage areas should be protected by posting warning signs both indoors and outdoors. Empty containers from toxic and flammable substances must be stored in specially designated areas.
Various acids are stored in special containers (braided bottles) indoors. Each bottle should be labeled with the name of the acid and its concentration.
It is not allowed to store quicklime at the construction site, slaked lime is stored in lime pits covered with boards, with hatches and fences up to 1 m high or in special containers.
Explosives should be stored, used and accounted for in accordance with the current "Instructions on the procedure for the storage, use and accounting of explosive materials."
Dinitrophenol and sodium dinitrophenolate should be kept moist in tightly sealed drums.
Cylinders with compressed gases and oxygen are stored in special closed ventilated rooms, isolated from sources of open flame.
Storage of drums with calcium carbide and cylinders with oxygen, cylinders with acetylene or coke oven gas in the same room is prohibited.
Construction and installation pistols and cartridges for them are stored in a warehouse in separately sealed (sealed) steel cabinets.
Warehousing of special building materials. The organization of the proper storage and placement of materials both in warehouses and on construction sites is of great importance for the normal and safe conduct of all construction work. On the territory allotted for storage, building materials are placed so that they do not close windows, doors, fire passages.
Materials are brought to the construction site in small quantities. They are placed so that the passages between the stacks are at least 1 m, the width of the passages is set depending on the dimensions of the vehicles.
Brick delivered without containers is laid flat in cages 25 rows high, and 13 rows on edge. Bricks in containers are stacked in one row, and in packages on pallets - in two tiers.
Rubble stone, asbestos-cement and gypsum slabs are stacked in piles to a height of 1 m. Reinforced concrete crossbars, lintels and columns are stacked up to 2 m high with wooden spacers between rows. Reinforced concrete floor slabs and floorings are stacked in stacks up to 10 ... 12 rows, but not higher than 2.5 m. Foundation blocks and basement wall blocks are stacked with gaskets no more than four rows up to 2.5 m high. pipes of large diameters) are laid with a height of 1.2 m with spacers between the rows and reinforced with stops so that they do not roll out.
Loose powdered materials (cement, gypsum, alabaster, chalk) are stored in warehouses or under sheds in bags, which are stacked up to 3 m in height. When laying stacks above 1.5 m, it is necessary to arrange comfortable ladders with railings. If bulk materials do not come in bags, they are stored in bulk in closed chests at the construction site, and in warehouses - in bunkers. The bins are made 1X1 m in size. The loading openings of bins (silos) with a bin depth of 1.5 m or more should be covered with bars. Sand, gravel and crushed stone are stored in bulk, taking into account the angle of repose, or strong retaining walls are arranged.
Roundwood (logs) is stacked in 2 m high stacks with spacers between rows. To prevent the logs from rolling out, stops are arranged on both sides in the form of racks with struts. Boards are stacked in piles or cages. They can be stacked parallel to each other with spacers in five rows no more than half the width of the stack. The direction of laying boards can be changed after each row, reaching a height no more than the width of the stack. Barrels with building materials are stacked in no more than two rows in height with gaskets, and in the supine position - with gaskets and case stops so that they do not roll out.
Radiators are laid: separate sections in stacks no more than 1 m high, and assembled - in one row.
Depending on the method of delivery, goods are divided into piece, bulk and bulk. All of them, in turn, are divided into other types:
piece - into small pieces (weighing up to 50 kg) - wooden and metal products, roofing and heat-insulating materials, packages, packaged pieces, etc.; building structures - panels, trusses, blocks (sanitary cabins, elevator shafts); rolled metal - rod, corner, channel; and lashes of pipes; containers and packages; sets of cargoes (piece cargoes selected for the technological stage); lengthy; technological equipment and construction vehicles (when transported to facilities); forest - round wood,;
bulk - for bulk (, non-metallic materials) and blocky (rock, rubble); porous aggregates for concrete (thermolite, agloporite); powdery and dusty materials (cement, lime, ash, mineral powder); bulk - on water; semi-liquid cargoes (concrete and mortar mixes); bitumen and mastics (heated up to 200°С); binder load - hot asphalt; lime milk; liquid fuel.
The most effective form of material and technical support (MTO) of the facilities under construction is a complete set - a complete supply of materials, products and structures on time, subordinating the MTO system to the technological rhythm of in-line industrial construction. The complete delivery of goods to the construction site is calculated in advance and prepared by the production and technological equipment management service (UPTK).
There are three main types of kits: technological, delivery and transport. Technological kit - a set of material resources required for the construction of an object or its part (floor, section, grip), delivery kit - part of the technological kit supplied to the construction site in order of priority by timing, transport kit - part of the supply kit delivered to the construction site for one flight, taking into account the technological sequence of the construction of the object.
In order to improve the storage of goods in the UPTK and at the facility, as well as to increase the level of mechanization of loading and unloading operations, containers and packages are widely used during picking. A container is an inventory special reusable container for bulk piece building materials and products, adapted for mechanized loading, unloading, short-term storage of goods. By carrying capacity, containers are divided into low-tonnage (0.625 and 1.25 tons), medium-tonnage (2.5 and 5 tons) and large-tonnage (10, 20 and 30 tons). A package is an enlarged batch of piece cargo (boards, joinery, bricks). Packaged goods are transported on pallets, which by their design are divided into flat, rack and box.
In addition to the advantages discussed above, the equipment provides: centralized delivery of material resources directly to the construction site; improvement of warehousing and loading and unloading operations; reduction to a minimum of stocks of materials at the construction site; liquidation of intermediate warehouses of materials in all parts of construction organizations; high labor productivity.
Loading and unloading works currently continue to be very labor intensive, they employ about 10% of all workers in construction. To reduce the labor intensity of these works, they should be carried out in strict accordance with the PPR, which reflects the volume of cargo transportation by nomenclature and terms, the organization of storage facilities at the facility, the location and equipment of construction cargo unloading points, the procedure for unloading and storing main cargo.
Loading and unloading operations must be carried out in a specially designated area with an even and durable surface (concrete, crushed stone, plank) and in compliance with. It is allowed to carry out work on planned unpaved areas capable of absorbing the design (according to the project) load from stored goods, vehicles and hoisting and transport machines.
Carrying out loading and unloading operations should be mechanized as much as possible. The level of mechanization is determined by the coefficient
where Q - the amount of cargo loaded or unloaded in a mechanized way 20bsh - the total amount loaded or you. loaded cargo.
A large number of specialized loading and unloading machines are used in construction. According to the principle of operation, they are divided into machines and installations of cyclic, continuous and pneumatic action, as well as machines designed to work with bulk materials in railway transport:
cyclic machines - used when working with bulk cargo: equipped with a straight shovel, dragline, loading buckets or special loading equipment; planner excavators; single-bucket universal loaders; electric forklifts; special loaders and unloaders; cyclic machines used to work with piece cargo include various types of self-propelled jib cranes; conventional design and loader cranes; gantry loader cranes, timber loaders, electric pilers, electric hoists;
machines of continuous action - designed for scooping, transportation and loading of bulk and small-piece cargo in a continuous stream: bucket loaders; conveyors (belt, bucket belt, elevators, screws);
pneumatic machines - used for cargo processing of powdered and pulverized building materials: pneumatic unloaders of suction and suction-pressure action; pneumatic screw lifts and pumps; chamber and jet pumps; aeration installations; pneumatic bottom and tank unloaders;
machines and installations for unloading railway cars and platforms with bulk cargo: various types of unloading machines operating on the conveyor principle of loading and transporting cargo; machines and installations for restoring the flowability of frozen materials based on loosening (vibratory rippers, vibroimpact action, drill-cutting rippers) and cutting; gondola car cleaning machines; hatch lifts; shunting devices (for the movement of wagons along the unloading fronts).
Transportation of building materials includes loading at the place of departure and unloading at the place of arrival. The processes of loading and unloading are currently fully mechanized; for these purposes, machines and mechanisms of general and special purposes are used.
According to the principle of operation, all mechanisms for loading and unloading operations are divided into two groups that operate independently of vehicles and mechanisms that are part of the design of vehicles.
- 1. The first group of mechanisms includes all types of cranes, cyclic and continuous loaders, mechanical shovels, mobile belt conveyors, pneumatic unloaders, etc.
- 2. The second group includes dump trucks, vehicles with self-unloading platforms, autonomous vehicles for self-unloading and loading, etc.
Cranes boom automobile, pneumatic-wheeled and caterpillar, tower, gantry, bridge, beam cranes are widely used for loading and unloading reinforced concrete and metal structures, equipment, materials transported in packages, containers, etc. Cranes equipped with special grippers and grabs are used for loading and unloading timber, crushed stone, gravel, sand and other bulk and small-sized materials. Cranes equipped with special bucket bunkers are used to supply the concrete mix to the work site.
Loaders are widely used in construction. With their help, they perform a significant amount of loading and unloading operations due to their high mobility and versatility. The most widely used in construction are universal single-bucket loaders, multi-bucket loaders and forklifts.
Single-bucket self-propelled loaders are equipped with a bucket for loading and unloading loose and lumpy materials. As attached and replaceable equipment, they can be equipped with fork lifts, jaw grip, bulldozer blade, ripper, backhoe excavator bucket. Single-bucket loaders are produced with front dumping of the bucket, unloading to the side and unloading back. At construction sites, loaders are used to unload and move goods over short distances, move them to lifting and transport mechanisms, to load receiving hoppers of mortar and concrete units, and for various auxiliary works.
Bucket loaders (continuous action mechanisms) are designed for loading bulk and small-sized materials into dump trucks and other vehicles. This is a self-propelled machine, on the frame of which a scooping mechanism is fixed - a feeder and an elevator or conveyor. Such machines are produced in several types; they differ in the design of the feeder - raking screws, scooping ball head, raking paws, etc.
Forklift trucks have a telescopic fork lift as a working body; crane boom, bucket, clamps for piece cargo and other devices are used as interchangeable equipment.
Loaders with a telescopic boom are widely used, which can be called universal, as they are able to load bulk building materials, containers, and can also be used as lifts with a platform for workers. Lifted loads reach (from different manufacturers) 3.2...4.5 m, lifting height - up to 13 m. , various buckets, crane hook, buckets for concrete. The speed of movement of loaders reaches 25 km/h. Two or four wheel drive, hydrostatic transmission and a 90° rear axle swivel provide high power and agility. The advantage of this type of loaders is the full lifting and lowering of the boom within 10 s, extension and retraction - up to 14 s, respectively. The telescopic loader can be used due to this as a controlled belt conveyor for moving goods through openings into and out of the premises. When the loader is working with an aerial platform, all the control functions of the mechanism and boom can be switched to the platform.
Self-unloading vehicles, in addition to dump trucks and cement trucks, include cars with craneless self-unloading devices for long structures or autonomous crane devices. building dwelling
The mass use of small-piece materials and products at construction sites has led to packaging - the formation and fastening into an enlarged unit of such goods, which ensure their integrity, safety when delivered under established conditions and allow mechanizing loading and unloading and storage operations. Special technical means are used - packages, universal and special containers, designed to transport a certain type of cargo.
Loading and unloading works in construction
Loading and unloading operations of the main material elements of construction processes (non-metallic materials, building structures, timber, metal, etc.) are now almost completely mechanized. For the mechanization of loading and unloading operations are used
general construction and special machines and mechanisms. According to the principle of operation, all machines and mechanisms that carry out loading and unloading operations are divided into the following groups: those operating independently of vehicles and being part of the vehicle structure. The first group includes special loading and unloading and conventional assembly cranes, loaders of cyclical and continuous action, mobile belt conveyors, mechanical shovels, pneumatic unloaders, etc. The second group includes dump trucks, transport devices with self-unloading platforms, self-unloading facilities, etc. Special loading and unloading and conventional cranes (beam cranes, overhead cranes, gantry, tower, pneumatic wheeled and caterpillar boom cranes, truck cranes, etc.) are widely used for loading and unloading reinforced concrete and metal structures, equipment, materials transported in packages , containers, etc. Cranes equipped with special gripping devices and grabs can work on loading and unloading timber, crushed stone, gravel, sand and other bulk small-sized materials.
Loaders in construction have become widespread. The widespread use of loaders in construction is due to their high mobility and versatility. The most widely used in construction are universal single-bucket loaders, auto-loaders and multi-bucket loaders.
Bucket loaders (continuous action) are designed for loading bulk and small-sized materials into dump trucks and other vehicles.
Forklifts are general purpose material handling machines. They serve for the mechanization of reloading and lifting and transport operations on sites, mainly with a hard surface. The main working body is a telescopic lift with forks.
Types of soils, their technological properties.
In the construction industry, soils are called rocks that occur in the upper layers of the earth's crust. The properties and quality of the soil affect the stability of earthworks, the complexity of development and the cost of work. To select the most efficient way of performing work, it is necessary to take into account the following main characteristics of soils; density, moisture, cohesion, looseness and angle of repose. Density is the mass of 1 m3 of soil in its natural state (in a dense body). Humidity is characterized by the degree of saturation of the soil with water, which is determined by the ratio of the mass of water in the soil to the mass of solid particles of the soil and is expressed as a percentage. With a moisture content of more than 30%, the soils are considered wet, and with a moisture content of up to 5%, they are considered dry. Cohesion is determined by the initial shear resistance of the soil. From the density and adhesion between soil particles mainly. depends on the productivity of earthmoving machines. The classification of soils according to the difficulty of their development, depending on the design features of the earth-moving machines used and the properties of the soil, are given in the ENiR. So, for single-bucket excavators, soils are divided into six groups, for bucket-wheel excavators and scrapers - into two, and for bulldozers and graders - into three groups. When developing soils manually, they are divided into seven groups. Building codes and regulations set the slope steepness values for permanent and temporary earthworks, depending on their depth or height. The slopes of embankments of permanent structures are made more gentle than the slopes of cuts. Steep slopes are allowed when constructing temporary pits and trenches.
Due to the fact that some processes performed during earthworks are associated with the passage of electric current through the soil (dehumidification by electroosmosis, thawing by current), the electrical conductivity of the soil is also of practical importance. Since the mineral particles that make up the soil are usually not conductors, the electrical conductivity of the soil depends on the degree of its saturation with moisture. In the process of earthworks, one has to deal with the phenomena of freezing and thawing of the soil, and these processes can be natural and artificial. Therefore, the thermophysical characteristics of soils are also important - their heat capacity and thermal conductivity. They are also more dependent on soil moisture, as the corresponding values for water are much higher than for mineral particles.
Types of earthworks
According to the duration of use, earthworks can be permanent or temporary. Permanent structures are constituent elements of facilities under construction and are intended for their normal operation. Such structures include canals, excavations and embankments of roads and railways, dams of hydraulic engineering and regulatory structures, water wells, etc.
Temporary earthworks are arranged during the construction of an underground or buried part of buildings, engineering networks, communications, etc. After that, they are partially or completely eliminated. The recesses, in which the width is commensurate with the length, but not less than 1/10 of the length, are called pits, with a width of less than 1/10 - trenches. Pit pits are dug out, as a rule, during the construction of the buried part of bulk structures (foundations, basement floors: technical rooms designed to accommodate equipment for sanitary and technological systems). Trenches are dug when laying linearly extended communications, external networks of water supply, sewerage, gas supply, heating, power supply, etc. When arranging excavations at construction sites that do not have width restrictions, as well as in order to ensure the maximum level of mechanization of earthworks, earthworks with a trapezoidal cross profile. Its main characteristics are depth (h), width along the bottom (b) and on top (B), laying of slopes (a), slope base, slope angle. The depth of development is determined by the difference in the marks of the day surface of the working (edge) and the bottom (slope base).
The width along the bottom of the excavation is equal to the width of the structure element being erected in the excavation (A) plus the size of the gaps (c), depending on the nature of the processing of the external surfaces of the element. The value of the broadening of the bottom of the pit (c) must be at least 0.6 m. In recesses of a rectangular profile, the value of the broadening, in addition, depends on the depth of the recess and the type of wall fastening. The width along the top of the excavation is determined as the sum of the width along its bottom (b) plus the value of the two slopes (a). Under the laying of the slope is understood the value of the projection of the slope line on the horizontal.
The reciprocal of the slope is called the slope factor (m). The value of m is determined by the type of soil, the degree of its watering, the duration of the excavation and its depth. The more monolithic the soil and the greater its water content, the greater the steepness of the slope of the excavation. With a depth of excavations of more than 6 m, it is necessary to install small horizontal platforms called berms. Slopes below berms tend to be less steep than those above berms. The exception is when the soils below the berms are dry and stronger than in the upper horizons. In temporary recesses, the steepness of the slopes is assumed to be greater than in permanent ones.
GROUND AT CONSTRUCTION SITE PLANNING
There are the following most common methods for determining L CP. :
a) analytical (method of static moments);
b) grapho-analytical (Kutinov's method);
c) graphic;
d) on the basis of a chess balance sheet;
e) based on linear programming (transport problem).
1 Grapho - analytical method
Based on the construction of graphs of progressive results on the sides of the construction site. The average distance of soil movement in this case is found by the formula
L CP \u003d L x 2 +L y 2, m
where: L x , L y - respectively horizontal and vertical projection L SR, m.
L x =W x /∑V Bi
where: W x , W y - the area of the figures, limited by the graphs of the cumulative results of excavation and embankment along the horizontal and vertical sides of the site, respectively, m 3.
2. Graphical method
after plotting the progressive totals on the sides of the construction site, parallel to the X and Y axes, the middle lines are drawn, spaced from the axes at a distance of V H /2 and V B /2. After that, the points of intersection of the middle lines with the graphs of cumulative totals are set and they are demolished on the site plan. At the intersection of the projection lines from the points, we obtain the position of the centers of gravity of the embankment and excavation, respectively. As L SR, the distance between the obtained centers of gravity is taken
3. Analytical method.
It is based on finding the centers of gravity of the cut and fill by the method of static moments of the cut and fill points relative to the X and Y axes according to the formulas
X V DH =S B y /∑V Bi =∑ V Bi х X Bi /∑V Bi , m
Y V DH =S B x /∑V Bi =∑V V i х X V i /∑V V i , m
X H CT =S H y /∑V H i =∑V H i x X H i /∑V H i , m
Y N CT =S N x /∑V N i =∑V Hi x X Hi /∑V Hi, m
where: S B y , S H y , S B x , S H x - static moments of excavation and embankment relative to the Y and X axes, respectively, m 4 ; V Bi , V Hi - the volume of the i - point of excavation or embankment, respectively, m 3 ; X Bi , X Hi , Y Bi , Y Hi - coefficients of the centers of gravity of the i -th point of the cut or embankment in the coordinate axes XOY.
After finding the centers of gravity of the excavation and embankment, L СР is determined as the distance between them according to the Pythagorean theorem
L CP \u003d (X V C.T. - X N C.T.) 2 + (Y V C.T. - Y N C.T.) 2, m
4. Based on the chess balance sheet
The distribution of soil from cut points to fill points can be carried out in the following ways:
a) common sense
b) by the smallest distances
At the final stage, the following soil movement distances are determined:
a) the total average distance of soil movement within the construction site L СР
L O CP =(∑V ij x L ij +∑V kj x L kj +åV p j x L p j)/(∑V ij +∑V kj +åV p j) , m
where: V ij , V kj - volume of soil moved from excavation points i or “pit” to embankment points j, m 3 ; L ij , L kj - distance of soil movement from excavation points i or “pit” to embankment point j, m.
b) the average distance of soil movement from the leveling cut to the leveling embankment L CP
L PL SR =∑V ij х L ij /∑V ij , m
c) the average distance of soil movement from the pit to the leveling embankment L CP
L K CP =∑V to j x L kj /∑V kj , m
When determining L O CP, the volumes of soil of the reserve and dump in case of a distance of removal or delivery of soil is more than 3. . .5 km are not taken into account.
5. Based on linear programming methods
average travel distance
L 0 SR \u003d L PL. SR. m
37 The calculation of LIA is to determine the required amount pumping units, filter pitch and depth of their immersion.
S=h gr +0.5+e ; m
where S is the required lowering of groundwater, m
h gr - groundwater height
e is the height of the capillary rise of water, m;
where k is the filtration coefficient
where Y is the pressure at the design point, m
H is the thickness of the aquifer
A \u003d √F u / π; m
where A is the reduced radius of the dewatering system, m
F u - reduced area of the inner contour of the wellpoint system, m
R=A+2*S*√k*H ; m
where R is the radius of influence of the system, m
Q c =(2*π*k*m*(H-Y))/(lnR/A); m 3 / day.
where Q c is the total inflow of water, m 3 / day.
Q c h \u003d Q c / 24; m 3 / hour.
where Q c h is the total inflow of water per hour, m 3 / hour.
where m is the average flow thickness, m.
N y =L ktotal /L before; PCS
where N y is the number of pumping units, pcs;
L ktot - the total length of the collector, m;
L before - the maximum length of the collector
L k = L ktot / N y ; m
where L k is the length of the collector per 1 installation, m
Q y =Q c / N y ; m 3 / day.
where Q y is the inflow of water to one installation, m 3 / day.
Q y h \u003d Q y / 24; m 3 / day
where Q y h is the influx of water to one installation per hour, m 3 / day.
n=L k /2*G; PCS
where n is the required number of wellpoints, pcs;
G – step of wellpoints, m.
q= Q y h / n; m 3 / day
where q is the water inflow to each wellpoint.
The limiting flow rate of one wellpoint is determined according to the schedule.
The distance from the aquiclude to the reduced GWL at the wellpoint is determined at a different step:
y g ’ \u003d y n -h in + ξ * Q y / (k * h) + 1.34 * 10 -7 * ξ 1 * Q y 2; m
where y g ’ is the distance from the aquiclude to the lowered GWL, m;
y n - the height of the pump axis above the aquiclude, m;
h in - the estimated suction lift of the pump
ξ - value depending on the service life of the installation at the facility
ξ 1 - coefficient of pressure loss in the suction system, day 2 / m 5.
Let's define the condition of water filtration:
y g \u003d H-S * (1 + 2 * π * Ф * m ’ / (N * n * ln (R / A)); m
where m ’ is the flow thickness on the wellpoint line, equal to y;
Ф – coefficient of resistance filtering;
According to the curve, we determine the pitch of wellpoints
Scraper traffic patterns
Depending on the size of the earthwork, the location of cuts, embankments, cavaliers or dumps, the following schemes of their movement are most often used during the operation of scrapers: elliptical, "eight", spiral, zigzag, shuttle-transverse and shuttle-longitudinal.
Work "along the ellipse" (Fig. 1, a) and "eight" (Fig. 1, b) is applicable when erecting embankments from one- and two-sided reserves, when arranging excavations with laying soil in embankments, dams and caves, during planning work in industrial and civil construction. When working with the "eight" in one pass, the scraper performs two operations of loading the bucket and two operations of its unloading, which shortens the path of the idle run and, as a result, increases the productivity of the scraper.
Fig.1. Scraper movement pattern
a - along an ellipse; b - eight; in - in a spiral; g - zigzag; e - according to the shuttle-transverse scheme; e - according to the shuttle-longitudinal scheme; rectangles show loading areas; shaded rectangles - unloading areas
The spiral scheme (Fig. 1, c) is used in the construction of wide embankments from bilateral reserves or wide excavations with a height or depth of up to 2.5 m. At the same time, work is carried out without the arrangement of exits and congresses.
Work "in a zigzag" (Fig. 1, d) is carried out during the construction of embankments up to 6 m high from reserves with a grip length of 200 m or more.
The shuttle-transverse scheme (Fig. 1, e) is used more often when erecting embankments and dams with a height of less than 1.5 m when working from bilateral reserves or when constructing canals and excavations up to 1.5 m with laying soil in dams or cavaliers. The productivity of the scraper along the zigzag is 15% higher, and with the shuttle-transverse - by 30% compared to the elliptical scheme.
The shuttle-longitudinal scraper movement pattern (Fig. 1, f) is used in the construction of embankments 5 ... 6 m high with slopes not steeper than 1: 2 ° with soil transportation from bilateral reserves.
The traffic pattern for each specific case should be chosen taking into account local conditions so that the traffic paths are the smallest. The greatest slopes of earth-carrying roads should be for scrapers: in the freight direction - when lifting - 0.12 ... 0.15, and when descending - 0.2 ... 0.25; in an empty direction - when lifting 0.15 ... 0.17, and when descending 0.25 ... 0.3.
Physical methods of drilling.
The main physical methods of drilling are thermal and hydraulic. Electrohydraulic, plasma, ultrasonic and some other methods are under development and production testing.
With the thermal method of drilling, rocks are destroyed by a high-temperature heat source - an open flame. The working body of the thermal drilling machine is a thermal drill with a fire-jet burner (Fig. VI. 3, a), from which a high-temperature gas jet is directed to the bottom of the well at supersonic speed. A mixture of finely dispersed kerosene with gaseous oxygen is fed into the combustion chamber through a nozzle. Formed inside the chamber, gaseous combustion products with a temperature of up to 2000°C under the action of pressure inside the chamber fly out at a speed of about 2000 m/s through the holes in the bottom of the burner and act on the bottom of the well. With the help of water, the burner is cooled and the destroyed rock is removed from the well.
Mobile thermal drilling machines on caterpillar and automobile tracks and hand-held thermal drills have, in principle, a similar device. A manual thermal drill (Fig. VI. 3, b) is a metal casing rod with a diameter of 30 mm, in which there is a burner with a cooling system. Kerosene and gaseous oxygen enter the burner at a pressure of 0.7 MPa, and water for cooling - at a pressure of 1.3 MPa.
Mobile thermal drilling machines can drill holes and wells with a diameter of up to 130 mm and a depth of up to 8 m, and hand-held thermal drills can drill holes with a diameter of 60 mm and a depth of 1.5 ... 2 m.
A variation of thermal drilling is the drilling of holes with the help of heated compressed air. In this way, holes are drilled with a diameter of 50 ... 70 mm and a depth of up to 2 m in frozen soils. For drilling, an installation consisting of a compressor, a heater and an air heater is used. From the compressor, compressed air is supplied through hoses to the heater through air tubes built into it and a preheating coke oven. A jet of compressed air, heated in an air heater to 90°C, is directed into the soil through a sleeve with a perforated tip, warms it up, loosens it and throws it out of the well.
The thermal method of drilling holes in comparison with the mechanical one is more efficient, and its productivity is 10...12 times greater when drilling the rocks of the crystalline structure.
The hydraulic drilling method (Figure VI. 3, c) is used to develop wells in light loams and quicksand. With this method, water is injected into the well through a string of pipes and a special slender nozzle attached to the bottom of the string. Water erodes the bottomhole, and the pipes sink into the ground. The hydro mass formed by the erosion of the soil is squeezed out under the pressure of water along the outer walls of the casing pipe, which is extracted from the soil by a winch. With the help of hydraulic drilling, wells up to 8 m deep can be drilled at a speed of up to 1 m/min.
Soil compaction with rollers
Rolling is carried out by self-propelled and trailed pneumatic rollers. The compaction force is achieved due to high contact stresses created by the gravity of the roller and the ballast load on the rolling plane (line) (up to 8 MPa).
Pneumatic rollers can be single-axle (weighing 10 - 25 tons), two-axle trailed (weighing up to 50 tons) and semi-trailed (single or two-axle weighing up to 100 tons). With light rollers, the required compaction of loose soils with a layer of 20-30 cm is achieved with a working width of up to 2.5 m. Heavy trailed pneumatic rollers weighing 25-50 tons provide soil compaction with a layer of 35-50 cm with a working width of 2.5-3.3 m semi-trailed pneumatic rollers are most effective, they provide high-quality compaction of cohesive and non-cohesive soils with a layer of 40 - 50 cm with a grip width of 2.7 - 2.8 m. ). Trailed and self-propelled drum rollers are less efficient than cam rollers due to the large area of pressure distribution.
To increase the contact pressure on the compacted soil and achieve high performance, cam or lattice rollers are used. The cams are steel profile pins 200 - 300 mm long, welded around the circumference to the drum shell. Such rollers are used to compact only cohesive soils. When compacting soils from coarse rocks, instead of cams, steel gratings from a corner or other steel profile are welded to the surface of the drums. Cam and lattice rollers provide soil compaction with a layer of 25 - 50 cm with a capture width of 2.7 - 3.3 m in 4 - 10 passes along the track.
Rolling of each layer of soil is carried out, as a rule, according to a spiral-ring pattern. The length of the grip is assumed to be 250 - 300 m. When compacting soils on grips of small width (it is difficult to turn the rollers), mainly self-propelled drum rollers are used, moving in a reciprocating pattern.
61. Compaction and vibrocompaction of soils.
The method of soil compaction by tamping is based on the transfer of shock loads to the compacted soil. Unlike vibration and vibrotamper methods, this method has a significantly higher impact energy due to the high speed of load application at the moment of impact of the working body with the soil, due to which this method provides compaction
cohesive and non-cohesive soils in layers of great thickness (practically up to 2 m). The method of soil compaction by tamping has found the widest application in industrial construction when arranging soil cushions under the base of the foundations of buildings and structures, technological equipment and floors. This method is also used for ramming pits in subsiding soils when constructing columnar foundations.
The combined method of soil compaction is based on the use of various combinations of static, vibration, vibrotamping and tamping loads on the soil. This method allows you to compact all types of soils and is mainly used for a wide range of works.
The method of soil compaction by vibration is based on the transmission of mechanical harmonic vibrations from working bodies (drums, wheels, plates, vibrating heads) to the compacted soil. The vibration method is divided into superficial and deep. The method of surface vibrocompaction of the soil is characterized by the fact that during operation the compacting working body is located on the surface of the soil and, making oscillatory movements, acts on it. With the deep method, the compacting working body is located inside the soil during operation.
The surface vibration method has found application in the compaction of non-cohesive and weakly cohesive backfill soils. The deep vibration method can be effectively used in the compaction of sandy soils, especially those in a water-saturated state. Depending on the main parameters of vibration, which are the frequency and amplitude of oscillations, vibration machines for surface soil compaction can also operate in vibro-impact mode. The amplitude of their oscillations is much larger, and the frequency of oscillations is less than that of vibration machines. In this case, vibration machines are called
vibrotamping, and the method of compaction is vibrotamping. The method of compacting soils by vibrotamping has found application in construction when compacting backfills in cramped places.
62. Deep compaction of soils.
Compaction with soil piles, displacement of soil during its radial compaction in the process of punching or punching wells and subsequently filling them with soil and layer-by-layer compaction
Deep compaction methods:
Physical
Soak
Drainage (vertical drainage)
Mechanical
Vibrocompaction
Soil compaction with piles
Soil compaction with pneumatic punches
Compaction with a spiral screed
Sealing with a working body in the form of a screw pile
Combined
water + vibration
(hydro-vibration compactor)
When compacting the soil, it is necessary to ensure optimal moisture, which requires the least energy consumption.
With sequential compaction, work is performed in a checkerboard pattern. The impact method is used to form wells. Duration of compaction of 1 layer - 30 sec. With 10-15 hits. For bulk and subsidence soils to a depth of 5-25 m. The surface (buffer) layer should be compacted.
Deep vibration compaction - for sandy water-saturated bases: bulk and alluvial sands. The implementation of the method is carried out by sequentially immersing the vibrating bar into the soil while simultaneously supplying water through the internal cavity, after immersing the vibrating bar to the required deep water supply stops and is carried out in addition to 4-5 lifting-lowering dry . Deep compaction with pre-soaking - for the device of subsidence properties reduced by deformability and compaction of soils: loess, loam, silty soils with a high filtration coefficient of at least 0.2 m / day. The compaction process is carried out under the action of the soil's own mass during soaking, and is quite long 2-3 months. Reducing the time of soil compaction up to 3-7 days is achieved with the use of additional compaction due to comflet explosions.
63. Quality control of soil compaction.
The quality of soil compaction can be controlled by the following most common methods: standard, cutting rings, radioisotope, probing, stamping, waxing, hole method. The choice of one or another method depends on the equipment of the laboratory, the nature of the structure, the volume of the embankment being erected and their class. seals determine the optimum moisture content and the maximum standard density using the SoyuzdorNII device. The method of cutting rings in determining the density of the soil skeleton in embankments is based on determining the density of wet soil in the volume of a metal ring with a capacity of 300 ... 400 cm3 (d / h = l), pressed into the compacted layer, and the moisture content of this soil. due to its simplicity, it is the most acceptable and widespread. Currently, radioisotope methods are most widely used in construction practice, since soil field laboratories on large earthworks were equipped with devices that use the absorption and scattering of gamma radiation and neutrons. The method of static and dynamic sounding as one of the types of control of the degree of soil compaction in embankments and backfills is the most efficient and simple of all existing control methods. The stamp indentation method is used to determine the strength of soil foundations. In particular, this method is widely used to control the quality of soil compaction of foundations under the floors of industrial buildings and foundations. The waxing method is mainly used to control soil compaction in winter conditions. clods. The quality of the soil laid in the body of the embankment can be considered acceptable if the number of control samples with soil density deviating from that specified by the project does not exceed 10% of the total number of control samples taken on the site, and the density of the soil skeleton in the samples should be no more than 0.5 g/cm3 below the density required (minimum).
64. Closed development of soils by a puncture method.
A puncture is the formation of holes due to the radial compaction of the soil when a pipe with a conical tip is pressed into it. The indentation is made with a hydraulic jack. A pipe link with a tip is laid in the pit and, after alignment with a jack, is pressed into the ground for the length of the rod stroke. After the rod returns to its original position, a pressure pipe (ramrod) is inserted into its place, and the process is repeated. At the end of the indentation of the first pipe link to the full length, the ramrod is removed, the next link is lowered into the pit, which is butt welded to the one already crushed into the ground. Next, the welded link is crushed, and the cycle is repeated a sufficient number of times until a puncture over the entire length of the section that cannot be dug in the traditional way. For each cycle, the pipe advances by 150mm. This method is practiced in highly compressible soils, holes are “pierced” for pipes with a diameter of 100 to 400 mm at a depth of more than 3 m. In slightly compressible soils (sand, sandy loam), in order to ensure the stability of the walls, in addition to horizontal force, it is necessary to apply transverse and vibration effects. At the same time, holes with a diameter of up to 300 mm are made.
65. Closed development of soil by punching.
The method is used for laying steel pipes with a diameter of 500 mm to 1800 mm, or collectors of square (rectangular) cross-section at a distance of up to 80 m. The technology is as follows: pipe links are sequentially pressed into the soil, inside which the soil is developed and removed by means of a screw installation. In easily eroded soils, removal is carried out by the hydromechanical method (the soil inside the pipe is washed away with a jet of water and the pulp is pumped out with a pump). Often pipes are used as cases for placing the main pipelines in them. The method of horizontal drilling in closed excavation.
Drilling is used for laying pipelines in clay soils with a diameter of 800 to 1000 mm for a length of up to 100 m. The end of the pipe is equipped with a cutting crown of increased diameter, the pipe is driven by a motor installed on the edge of the pit. The translational movement of the pipe is reported by a rack jack with an emphasis on the back wall of the pit. The soil filling the pipe from the inside can be removed through the pipe being laid using a screw installation by the hydromechanical method by washing out the soil inside the pipe with a jet of water and then pumping out the pulp with a pump (in easily eroded soils) or bailers with an extension of their handle.
Purpose and types of piles.
According to the method of deepening into the ground, the following types of piles should be distinguished:
a) driven reinforced concrete, wooden and steel, immersed in the ground without excavation with the help of hammers, vibrators, vibropressing and indenting devices, as well as reinforced concrete shell piles buried by vibratory drivers without excavation or with partial excavation and not filled with concrete; b) reinforced concrete shell piles, buried by vibratory drivers with excavation of the soil and filled partially or completely with a concrete mixture; arranged in the ground by filling drilled wells with a concrete mixture or installing reinforced concrete elements in them; and driven piles, in addition, on low-compressible soils you. Hanging piles should include piles of all types, based on compressible soils and transferring the load to the foundation soils with their side surface and lower end. Driven reinforced concrete piles with a cross section of up to 0.8 m incl. and shell piles with a diameter of 1 m or more should be divided: a) according to the method of reinforcement - into piles and shell piles with non-stressed longitudinal reinforcement with transverse reinforcement and prestressed with rod or wire longitudinal reinforcement (from high-strength wire and reinforcing ropes) with transverse reinforcement and without it; b) according to the shape of the cross section - into square, rectangular, tee and I-section piles, square with a round cavity, hollow round section; c) according to the shape of the longitudinal section - into prismatic, cylindrical and with inclined side faces ( pyramidal, trapezoidal, rhomboid); d) according to design features - into solid and composite piles (from separate sections); hollow piles with a closed or open lower end or with a camouflage heel. Stuffed piles are divided into: a) stuffed open, arranged by immersing inventory pipes, the lower end of which is closed by a shoe or concrete plug left in the ground, with the subsequent extraction of these pipes as the wells are filled with concrete mixture; in the form of a pipe with a pointed lower end and a vibrator fixed on it; Drilled piles according to the device are divided into: a) bored piles of a solid section with and without widening, concreted in wells drilled in silty-clay soils above the groundwater level without fixing the walls of the wells, and in any soils below the groundwater level - with fixing the walls wells with clay mortar or inventory retrievable casing pipes; b) bored hollow circular cross-section, arranged using a multi-section vibrocore; the formation of widening with an explosion and filling the wells with a concrete mixture; with or without broadening, laying monolithic cement-sand mortar and lowering cylindrical or prismatic solid-section elements with sides or diameters of 0.8 m or more into the wells; reinforced concrete pile.
Separate concreting
In order to create optimal conditions for safe and highly productive work of workers engaged in loading and unloading operations, they plan material receiving sites with a slope of no more than 5%, strengthen their coatings, provide surface water runoff, and organize the possibility of free entry and exit of vehicles mainly according to the ring scheme.
In appropriate places, signs are installed: “Entrance”, “Departure”, “U-turn”, etc. Loads, lifting mechanisms and vehicles are placed taking into account the minimum distance for transferring cargo from the place of capture to the place of installation or laying.
For the mechanization of loading and unloading operations, a significant fleet of general construction and special machines and mechanisms is used. However, their labor intensity is still high. Loading and unloading employs about 10% of the total number of workers in construction.
When unloading bricks manually, observing all the necessary precautionary rules, the losses are about 7%, often brick breakage reaches 10-12%, and 1 man-hour is required to unload 1 ton of bricks. The use of forklifts for this operation makes it possible to reduce the unloading time to 0.037 man-hours, while the loss of bricks is no more than 1%.
For the mechanization of small-volume, dispersed construction and installation and loading and unloading operations in the conditions of a construction site, it is advisable to use single-bucket wheel loaders as the most maneuverable and mobile. Their advantages include the ability to independently collect and transport goods, high maneuverability in the work area, which is especially important in dense urban development and reconstruction.
For intra-object and inter-object transportation of bulk, lumpy and liquid materials, dump motorized trucks are used instead of more expensive dump trucks.
The processing of piece cargoes is carried out practically in a mechanized way and makes up about 30% of the total volume of loading and unloading operations in construction, and in terms of labor intensity - less than 2% of all labor costs of workers involved in this type of work.
The share of small-piece cargo in the total volume of transportation of construction cargo is 4%. But the performance of transport and cargo operations during transportation accounts for over 30% of labor costs. Moreover, this is predominantly manual, heavy, inefficient work. Therefore, the task of mechanization of manual labor in the transportation of such goods is extremely relevant. Furs: the lowering of transport and cargo operations with small-piece cargo is possible only if they are enlarged using containerization and packaging facilities
For storage, movement and warehousing of goods (with a gross weight of 0.251 and more), carrier packaging is used as a multi-turn packaging tool for inter-factory and inter-departmental transportation. It can be folding, frame, rack, box (including with an opening or missing wall), mesh, conical.
As a carrier container with a capacity of more than l m 3, reusable cargo containers are used, which are used for the transportation and temporary storage of goods without intermediate reloading. Freight containers with a gross weight of more than 10 tons are large-tonnage, from 2.5 to 10 tons - medium-tonnage, less than 2.5 tons - low-tonnage. For piece cargo of a wide range, enlarged cargo units and small piece cargo, universal containers are mainly used; for gases, liquid and bulk cargo - tank containers; for other specific cargoes - specialized containers (individual, group, isothermal).
Unloading viscous oil products from railway cars is a rather complicated technological operation. There are many ways to heat a frozen and thickened oil product, for example, live steam.
