How to make an ice crossing on a river. Crossing tanks through various obstacles. For design, design and operation

For some rivers in the European part of Russia, strengthening the ice crossing by freezing did not give practical results, since the gain of several days at the beginning of the operation of the crossing was lost in the spring: the crossing became unsuitable due to more intense melting of the frozen layer.

To protect ice from cracking and mechanical wear, as well as better adhesion of wheels and tracks to the road surface during snow removal works It is advisable to leave a layer of loose snow 5-10 cm high or 3-5 cm compacted on the roadway.

In case of sudden drops in water, you must carefully monitor the condition of the ice using control holes and reduce the permissible load by 20%.

Ice that does not lie directly on the surface of the water is very unreliable and, as a rule, unsuitable for crossing (except for areas of continuous freezing). This must be taken into account, since in winter, when the water level drops, there are cases when the ice freezes to the shores and does not immediately sink, then an air cavity forms between the ice and water. The ability of ice to withstand loads, in addition to its mechanical strength, is also characterized by its buoyancy ( specific gravity ice 0.9). In addition, due to the known elasticity of ice, the load is distributed over a strip up to 10-15 m wide. Observations have established that when the water horizon drops and the presence of an air cavity, the strength of the ice can decrease by more than 2 times.

To strengthen the ice of the crossing and to distribute pressure on the ice more evenly, boards, beams and brushwood are used. On a 5-6 m wide strip cleared of snow, a 5-8 cm thick flooring is laid, which is covered with a thin layer broken ice or snow 4-6 cm thick and fill with water. The rate of ice growth depends on the air temperature. The freezing time of a 7 cm thick flooring flooded with water depends on the air temperature, so when:

10°C - 8 hours
-20°С – 5 hours
-30°С – 3 hours
-40°C - 1.5-2 min

During the construction of the Bratsk hydroelectric power station on the river. The hangar was widely used to strengthen the ice crossing with ice sheets, which increased the operating time of the ice crossing by more than a month (taking into account the timely removal of the ice sheets from the ice), preserved the transport connection between the banks, slightly increased the weight of single cargo, and also strengthened the crossing on alternate lanes traffic in February-March, when the lanes were heavily used.

When constructing timber decks along the roadbed, the same purlins were laid out on the crossbars. The traffic lane consisted of two tracks. Each track had an outer wheel guard with a section of 20X20 cm and an inner one with a section of 10X10 cm.

The purlins to the crossbars and the wheel guards were secured with 300x100x10 mm brackets and 10x10x30 mm ruffs. The timber used was fourth grade. Average weight 1 linear m of the structure of the upper structure of the crossing was 1.06 tons.

As the ice thickness increases, the gain in carrying capacity, which depends on the superstructure, becomes less and less noticeable. So, if with a superstructure in the form of a rutted road surface made of wooden beams with a cross section of 15x15 cm, with an ice thickness of 10 cm, the crossing is strengthened by 2.84 times, while with an ice thickness of 28 cm, it is only 1.08 times.

Ice bends under load, forming a kind of ice bowl that moves with the moving car. As a result, an under-ice wave appears, propagating in the direction of movement.

Depending on the speed of movement, the propagation of the under-ice wave may lag behind the vehicle or ahead of it. If the speeds of the subglacial wave and the car coincide, the ice cover is disrupted.

The most unfavorable speed is in the range of 30-40 km/h, since this causes the ice to swing as much as possible.

On the ice crossing on the river. On the Volga in the area of ​​Kuibyshev, active formation of parallel and intersecting cracks was discovered at a distance of 30-40 m from the shore.

The depth of the river in this place reached 8 m, the speed of cars instead of the permitted 10-15 km/h was 25-30 km/h, i.e. it was close to the critical speed of wave propagation in the reservoir (30 km/h).

After the speed of cars in this section of the crossing was reduced to 10-15 km/h, the fluctuations in the ice and the formation of cracks stopped.

When working on ice crossings, it is necessary to determine the permissible time for parking cars on ice, since under prolonged load the ice is deformed, which can lead to its destruction. After the allowed parking time has expired, the vehicle with the cargo must be moved to a new location.

Particular attention should be paid to the operation of ice crossings in spring period and in the days of thaw.

At positive outside temperatures, ice recrystallizes, the ice acquires a needle-like structure, and its strength decreases by 2 times or more.

In the spring, a significant amount of water accumulates on traffic lanes, resulting from melting snow lying on ice.

Three to four days after meltwater appears on the ice, the bearing capacity of the ice decreases significantly. It is possible to allow vehicles to move through crossings covered with a layer of water of no more than 40 cm (provided the ice is sufficiently strong). When the ice thickness is 40-45 cm, without creating an upper deck, vehicle movement becomes dangerous. With the onset of thaws, it is necessary to take measures to remove snow banks from the boundaries of the clearing lane, drain water from the traffic lanes into the holes made outside the traffic lane; it is also necessary to organize careful monitoring of the decrease in ice thickness and switch the movement Vehicle where possible, to untraveled lanes.

The thickness of the ice during the construction of ice roads and crossings is controlled by drilling holes or holes in the ice every 25 m or every 100 m along the edges of the clearing strip. The ice thickness at the crossings ranges from 0.6 to 2.1 g, depending on the temperature and speed of the river flow in a given place.

Before transportation begins, an approximate calculation is made to determine the possible load that the existing ice cover can withstand.

When organizing an ice crossing, they are guided by the purpose of the crossing (pedestrian, automobile, etc.), the intensity of cargo traffic, the width, depth and speed of the river or reservoir, the characteristics of the ice cover (ice structure and thickness) and snow cover.

If the crossing is organized near an operating hydroelectric power station, then its operating mode must be taken into account. The ice road is cleared of snow to a width of at least 10 m from the center of the traffic lane in both directions and is marked with milestones. The distance between the milestones is from 15 to 20 m.

Ice roads are made only one-way and single-lane. The distance between two lanes is taken to be at least 100 m.
When determining the thickness of ice, the thickness snow ice(differs in structure and color) is not taken into account.

To determine the thickness of the ice, holes with a diameter of 6 to 10 cm are made on both sides of the road at a distance of 5 m from its longitudinal axis in a checkerboard pattern every 10–20 m along the length. The holes should be fenced with a snow roller 0.2–0.3 m high and 0.5 m wide, and also covered with boards. On the coastal section of the route, holes should be made every 3–5 m. This is necessary for timely detection of possible ice “hanging” at the points of entry onto the ice when the water level in a river or reservoir fluctuates. If the water level in these holes is less than 0.9 ice thickness, then this indicates the presence of ice “hanging” and the possibility of its collapse.

In such cases, the ice is artificially collapsed, and in these areas, in the coastal part, special ramps from the shore onto strong ice are arranged.

The frequency of ice thickness measurements is set by the local hydrometeorological service, but not less than once every five days, during a thaw - 2-3 times a day. The ice thickness, cm, required to pass cargo, t, is determined by calculation using the formula:
Htr = na?P
Where n– coefficient taking into account traffic intensity (for traffic intensity of less than 500 cars per day n= 1);
a– coefficient depending on the nature of the load distribution (for wheel load – 11; for track load – 9);
P – load mass, i.e.

The actual ice thickness is determined by the formula
H = (hpr + 0.5hmut) t1k2,
where H is the actual ice thickness, cm;
hpr – thickness of the transparent ice layer, cm;
hmut – thickness of the turbid ice layer, cm;
k1 – coefficient applied

during short-term thaws (k1 = 0,5);
k2 – coefficient taking into account the ice structure (with a conchoidal structure k2 = 1).

The permissible ice thickness for various loads is given in table. 3.7.
Table 3.7
Permissible ice thickness when organizing vehicle crossings across rivers andbodies of water

Notes:
1. When crossing on foot, the ice thickness must be at least 15 cm.
2. If the average air temperature over the last 3 days is above 0 °C, the permissible ice thickness (at a temperature of -10 °C) should be multiplied by a factor of 1.5.
3. The values ​​indicated in the table are determined for freshwater shell ice. If the ice is frozen or cloudy (porous), the thickness of the ice increases by 2 times, in reservoirs with salt water - by 1.2 times.
4. The carrying capacity of ice during frequent thaws and changes in water level should be established practically by passing loads over the ice. In this case, it is necessary to reduce the weight of the cargo by 2 times or more compared to the norms indicated in the table.
5. For stationary loads, the permissible ice thickness increases by 1.5 times or more.
With small ice thicknesses, natural freezing of ice occurs, which is achieved by regularly clearing the ice from snow, starting from a thickness of 15 cm. Artificial freezing of ice by watering is carried out when the ice thickness is 35–40 cm. Artificial freezing is carried out in layers 1 to 5 cm thick, the total thickness layer no more than 20–40% of the thickness of natural ice is allowed.

Requirements for diving work - dependence of the mass of the cargo or transport
means of ice thickness at a given air temperature and limit
distances from the ice edge

In the practice of military operations, tanks often have to cross rivers. Tank crossings across rivers can be carried out: on bridges, on ferries, ford, and in winter on ice.

Small rivers are usually fordable. Driving a tank while crossing a ford has some peculiarities. For example, when a tank is immersed in water, the pressure of the tracks on the river bottom decreases, as a result of which the adhesion of the caterpillar to the ground deteriorates. A strong current of water blows the tank to the side and takes it away from the intended direction of movement. In addition, water penetrates into the tank through various leaks in the hull during fording, and if the tank is in water long time, it may flood.

Before fording a river, you must carefully select a ford site, as well as inspect the tank and prepare it for fording. The ford site must be chosen where the river bottom is hard and level, and the banks are not steep or muddy; where there are convenient approaches to the river, and movement across the river is direct.

If the selected ford does not meet the requirements, then it must be prepared: the banks must be leveled at the entry and exit points, the river bottom must be cleared of underwater obstacles along the route, and the direction of movement must be marked with milestones.

Before crossing a ford, which is permissible for a given type of tank, it is enough to check the tightness of all lower hatches and plugs, lock the driver's hatch and put covers on the barrels of machine guns and cannons.

Before crossing, be sure to check the track tension; poorly tensioned tracks can come off while wading.

You should approach the ford secretly and using high gears. Before descending into the river, you should change to a lower gear; The descent from the shore should be smooth.

When crossing a ford, the tank commander, watching through the open hatch of the turret, directs the actions of the driver, giving him commands through the TPU. When wading, the tank must be driven along the shortest path and not go beyond the limits marked by milestones. You cannot change gears and stop the tank in the river, or make turns, because this will result in the tank stopping due to the low adhesion of the tracks to the ground. It is necessary to keep the engine speed constant all the time and move evenly, without jerking, otherwise the tank may skid and stop.

When crossing several tanks along one marked ford direction, you cannot begin wading until the tank in front reaches the opposite bank. If the river bottom is sticky, you should avoid moving along the rut of a tank passing ahead. When the river flows at a high speed, it is necessary to take into account the drift of the tank towards the current and choose a direction of movement slightly higher than the intended exit.

Preparing a tank for crossing a ford

Experience of the Great Patriotic War showed that our tanks can overcome fords that significantly exceed the standards specified in their tactical and technical characteristics. To do this, the tank must be additionally prepared: fill it with tow and coat the cracks of all hatches and plugs, the lower edge of the turret, the cracks of the gun mantlet and inspection slits with red lead or grease; insert spent cartridges into the chambers of cannons and machine guns; cover the engine and transmission compartments with a folded tarpaulin and strengthen the tarpaulin; prepare the tank for towing in case it stops in the water, for which purpose put the cables on the hooks of the tank, fasten the free ends of the cables to the tower, tie ropes to the control levers and bring their ends to the tower to turn off the clutches when towing a stopped tank.

In the case of crossing a river whose depth exceeds the height of the tank, the tank is equipped with long pipes extending upward. One of the pipes is installed in the tower for air supply, and the other is connected to the exhaust pipes for exhaust gas removal.

Driving through deep fords must be done in first gear; Maintain operating speeds uniform. The driver and tank commander must remain in the tank, unless the situation requires the presence of the entire crew in the tank. After exiting the water, place the tank tilted towards the stern, drain any water that has leaked into the tank, remove all sealing materials, start the engine and check its operation for 2-3 minutes; then check the operation of the radio station, external condition batteries and chassis; if necessary, replace the lubricant, and also check the fastening of the plugs and bottom hatches.

If the tank has stopped and stood in the water for a short time, then it is necessary to change the oil in the engine, gearbox, final drives and remove water from the cylinders, for which unscrew the air valve caps, press wooden block onto all valve stems and turn the crankshaft until water flows out.

A tank that has been in the water for several hours must be opened and checked for units and electrical equipment.

Tank crossing by ferry

If it is impossible to ford a water barrier, the crossing will be organized according to built pontoon bridges or on ferries.

In loading time for ferry and when unloading the tank into Only the driver should be there. The tank commander must use signals from outside to control the actions of the driver. Install tanks on the ferry needs to be so that they go to shore forward. Drive into ferry is needed on low gear and on low speed; drive the tank smoothly and without jerking, so as not to break the mooring ropes and Not break the entrance walkways. Upon entry to ferry should take the right direction to the middle of the ferry, no allow stops and Not make U-turns. The tank must be stopped at ferry center and slow him down. When the ferry moves along river tank commander and the driver must be near the tank; other crew members can assist in ferry movement.

The procedure for crossing a tank across the bridge

It is allowed to move along the bridge at the speed specified by the commandant of the crossing, but not higher than 8–10 km/h; the distance between tanks must be maintained within 30–50 m. When entering and exiting the bridge, as well as when moving along the bridge, do not stop, so as not to create “traffic jams” at the crossing. On the bridge, avoid sudden braking and jerking, move evenly without changing gears, level the tank smoothly and drive it in the middle of the bridge.

In order to camouflage from enemy air, underwater bridges are often used for crossing. The top deck of such bridges is below the water level. The dimensions of the flooring are indicated by milestones.

On road bridges, as a rule, you should drive in the middle, at a reduced speed. High speed movement of the tank over uneven flooring causes additional shock load on the bridge. You cannot stop on the bridge and change gears. Bridges that are strong, short, and have a level deck can be crossed without slowing down.

Crossing a tank on ice

The ice crossing must be previously scouted and prepared. The ice thickness for medium tanks should be within 50–80 cm. If necessary ice can be strengthened by a rutted road made of boards or logs or by building up ice.

Thin ice that cannot be strengthened must be broken and crossed by fording or using special means. The ice crossing site must be marked with milestones and cleared of snow.

Ice cracking during the crossing does not pose a danger if the ice is of sufficient thickness and water does not appear from the cracks; When water appears, the crossing must be stopped.

When crossing on ice, you must move in 2nd or 3rd gear, do not make stops, sharp braking or turns, smoothly change engine speed, maintain a distance between tanks of 30–60 m. A tank stopped on ice should be towed out using long tow ropes.

ON DESIGN, DEVICE AND OPERATION

ICE CROSSINGS

FEDERAL ROAD AGENCY

(ROSAVTODOR)

Moscow 2008

Preface

1 . DEVELOPED: "(candidate of technical sciences, senior research scientist, candidate of technical sciences, prof., engineer) using materials presented by (engineer), State Institution "Operation Management highways Republic of Sakha (Yakutia) (eng.), State Institution "Management of the Kolyma Highway" (eng.), Pacific state university(candidate of technical sciences, prof., candidate of technical sciences, associate professor, engineer)

2. INTRODUCED: Department of operation and safety of highways of Rosavtodor

3. ADOPTED AND ENTERED INTO EFFECT by order of Rosavtodor dated... No....

4. INTRODUCED to replace ONE

Real guidelines cannot be fully or partially reproduced, replicated or distributed as an official publication without the permission of Rosavtodor

Section 1. Scope

a) Real Guidelines apply to the design (including surveys), construction and operation of ice crossings installed on roads common use, as well as for communication in winter between populated areas (enterprises, etc.) or one-time (periodic or episodic) movement of vehicles (cargo).

b) The design, construction and operation of ice crossings and ice roads that are part of winter roads is carried out in accordance with documents establishing requirements (recommendations) for winter roads.

c) If it is necessary to detail and expand recommendations for the design, construction and operation of ice crossings that are part of winter roads, the use of these Methodological Recommendations is allowed, to the extent that they do not contradict the documents establishing requirements (recommendations) for winter roads.

a) SNiP Labor safety in construction. Part 1. General requirements

b) SNiP Labor safety in construction. Part 2. Construction production

c) GOST R Technical means traffic management. Road signs. General technical requirements

d) VSN 137-89 Instructions for the design, construction and maintenance of winter roads in the conditions of Siberia and the North-East of the USSR

f) Methodological recommendations on the procedure for carrying out technical examination ice crossings by the State Inspectorate for small boats Ministry of the Russian Federation for Affairs civil defense, emergency situations and disaster relief.

g) Regulations on the procedure for the import into and export from the Russian Federation of ozone-depleting substances and products containing them (approved by Decree of the Government of the Russian Federation No. 000 of 05/08/96)

Section 3. Terms and definitions

Winter road- a road with a road surface made of snow, ice or frozen soil, laid over land or the ice cover of a water barrier.

Ice road- part of a winter road laid along the ice cover of a water barrier (along a river bed, along the shore of a lake or bay).

Crossing– a structure (excluding bridges) for the movement of vehicles and people across a water barrier.

Ice crossing- a crossing in the form of a road laid along the ice cover of a water barrier. An ice crossing can be part of a winter road or temporarily replace an inactive bridge or ferry crossing in winter.

State customer– federal executive body (executive body of a constituent entity of the Russian Federation, local government authority) or government road management, as well as recipients of budget funds authorized by these bodies, when carrying out orders for work for budget account funds.

Project organization– a contracting organization performing design and survey work on the construction of an ice crossing.

Building company(operating organization) – a contracting organization performing work on the construction (operation) of an ice crossing.

Section 4. General provisions

a) The purpose of constructing and maintaining ice crossings is to ensure the safe passage of vehicles through a water barrier when an ice cover of the required thickness forms on it.

b) The main objectives of the construction and maintenance of ice crossings are: organization of the crossing; ensuring safe passage of vehicles across the crossing; traffic control at the crossing; monitoring the condition of the ice cover, reinforcement structures and ramps onto the ice; restoration of crossings.

c) The operating hours of ice crossings, the procedure and issues of payment for the transportation of vehicles and passengers, as well as flammable, dangerous goods and special transport, are determined by the customer in agreement with the administration of the region (district), territorial authorities traffic police The Ministry of Internal Affairs of Russia and the State Inspectorate for Small Vessels as part of the Main Directorate of the Ministry of Emergency Situations of Russia for the constituent entity of the Russian Federation (hereinafter referred to as GIMS GU EMERCOM of Russia for the constituent entity of the Russian Federation) in terms of ensuring the safety of people on ice crossings and safe conditions for the movement of vehicles and pedestrians along them.

d) Ice crossings must have a capacity that ensures the design traffic intensity established for them, and ensure the passage of design loads, safe conditions crossing crossings by vehicles and passengers (pedestrians).

e) For each crossing, a crossing design must be developed and, taking it into account design features and local transportation conditions, rules for using the crossing, regulating the procedure for passing vehicles and transporting passengers, rules for the safe behavior of drivers and passengers at the crossing.

Sections of the project for the construction and operation of an ice crossing are developed (or adjusted) annually with clarification of traffic intensity, throughput and load-bearing capacity of the crossing.

f) The tasks of operating ice crossings include: organizing the operation of the crossing with establishing an operating mode during the day; maintaining the established operating mode, serviceability of road signs and engineering equipment crossings; organization and regulation of vehicle traffic at crossings and approaches to them.

g) Main tasks current repairs and maintenance of ice crossings: monitor the thickness of the ice and its condition, the cleanliness of the roadway at the crossing and approaches, platforms for passengers, the serviceable condition of ramps and reinforcement structures, as well as life-saving means and equipment; repair and replace individual damaged and worn structural elements; seal cracks in the ice cover.

h) The maintenance personnel of ice crossings are obliged to ensure the trouble-free, safe and uninterrupted operation of the crossings in accordance with the approved schedules of their work, the good technical condition of the crossings, the security and safety of property, equipment, tools and materials at the crossing, correct operation, timely Maintenance, repair and maintenance of all structures, machines, mechanisms and crossing devices, provision of first aid.

Section 5. Organization of ice crossings

a) Ice crossings are organized in order to ensure the passage of transport through a water barrier when an ice cover of the required thickness forms on it in cases where there are no bridge crossings.

The selection of the crossing route, assignment of the train, survey, design, construction and operation of ice crossings are carried out based on their classification.

b) Ice crossings are classified:

By length: small (up to 100 m), medium (from 100 m to 500 m), large (over 500 m);

By duration of operation: regular (renewed on the same route every winter for a number of years), temporary (built for one winter), one-time (built for a one-time passage of a convoy of cars or any cargo);

According to the estimated traffic intensity: category I crossings with a traffic intensity of over 150 vehicles/day, category II crossings with a traffic intensity of 150 vehicles/day or less;

By type of reservoir: river, lake and sea crossings;

According to the salinity of the reservoir: crossings through fresh and salt water bodies of water or bodies of water of intermediate salinity;

By type of ice cover used for vehicle movement: natural ice cover (with and without clearing it of snow); cover thickened by freezing from above; cover thickened by freezing from below; cover thickened by freezing above and below;

According to the duration of the winter period with stable negative temperatures;

According to the presence of strengthening or reinforcement of the ice cover, its type and design.

c) At the stage of organizing an ice crossing, it is necessary to resolve the following issues:

Determination of the composition of the crossing (see paragraphs d)-e) of this section);

Preliminary selection of the crossing route (see paragraphs g)-h) of this section);

Determination of the carrying capacity of the ice cover (see paragraphs i)-l) of this section);

Determination of the operating mode of the crossing (see paragraphs m)-n) of this section);

Financing of work on the survey, construction and operation of the crossing (see paragraph o) of this section).

d) Ice crossings are arranged, as a rule, in the form of two lanes with one-way traffic (at large and medium ice crossings) or in the form of one lane with alternate passage of vehicles (at medium and small ice crossings) or two lanes with two-way traffic of vehicles on a common roadway (at small and medium-sized ice crossings).

When the traffic intensity is over 150 cars/day on ice crossings, 2 (two) one-way lanes should be provided with distances from each other of at least 50 m, maintaining the distance between cars according to Table. 1 and permissible speed.

Table 1