Safety requirements when developing trenches and pits. Tire tread depth - what is the minimum allowed What is the allowed depth of each indicator

Dmitry-35

What does this mean? Clause 2.3.4.4. Installation on one vehicle axle of tires of different sizes, designs (radial, diagonal, tubed, tubeless), models, with different tread patterns, frost-resistant and non-frost-resistant, new and reconditioned, new and with an in-depth tread pattern. - Does it also stop working?

This is removed from the Technical Regulations, but remains in the annex to the traffic rules (clause 5.5 of the List of faults)

The changes affected trucks with a permissible maximum weight of up to 3.5 tons, i.e. trucks of category B. Previously, on such vehicles, rubber could be used until 1 mm of tread remained. From January 1, 2013, the requirements will be slightly more stringent - 1.6 mm. For example, these requirements will affect small trucks (Gazelle, Mitsubishi L200, Volkswagen Amarok, etc.).

Error in the text: From January 1, 2013.... Still, I think, it means “From January 1, 2015”

GrammarNazi, Thank you! Changes have been made to the article.

If you notice something like this, be sure to write.

Good luck on the roads!

Vladimir-29

You can use summer tires winter period, if the road surface is not icy or snowy? In Crimea, winter temperatures are mostly above zero and there is no snow.

Can. At least in Crimea, at least in Vorkuta. The main thing is to fulfill the following point:

5.5. One axle of the vehicle is equipped with tires of various sizes, designs (radial, diagonal, tubed, tubeless), models, with different tread patterns, frost-resistant and non-frost-resistant, new and reconditioned, new and with an in-depth tread pattern. The vehicle has studded and non-studded tires.

Comments

How to understand (no more)?

5.2.3. With the remaining tread depth of winter tires intended for use on icy or snowy road surfaces, marked with a sign in the form of a mountain peak with three peaks and a snowflake inside it (see Figure 5.1), as well as marked with the signs “M+S”, “M&S ", "М S", during operation on the specified coating - no more than 4 mm.....

It turns out that with a tread depth of 3mm, operation is possible?

5.2. The tire is considered unsuitable for use:

In the table in the decoding: "L - mopeds, motorcycles, ATVs, etc.", there is no error

ATVs, and ATVs!!! So?????

5.2. The tire is considered unsuitable for use:

With the remaining tread depth of winter tires... - ...no more than 4 mm.

Is 3mm more than 4mm? No more, equals less!

“No more” is “less than or equal to,” not just “less.” From a mathematical point of view. Although in reality the boundaries and their affiliation cannot be accurately established.

lego, thanks for the info. You are right, the article will be corrected.

Good luck on the roads!

Vyacheslav-5

Hello.

2.3.4.4. Installation on one vehicle axle of tires of different sizes, designs (radial, diagonal, tubed, tubeless), models, with different tread patterns, frost-resistant and non-frost-resistant, new and reconditioned, new and with an in-depth tread pattern.

Vyacheslav, Hello.

There is no exception for a spare tire. If they stop you, you will be fined. Therefore, if your spare wheel is different from the other wheels, then use it as little as possible (immediately head to the nearest tire repair shop).

Good luck on the roads!

Hello.

2.3.4.4. Installation on one vehicle axle of tires of different sizes, designs (radial, diagonal, tubed, tubeless), models, with different tread patterns, frost-resistant and non-frost-resistant, new and reconditioned, new and with an in-depth tread pattern.

Is there an exception anywhere about the spare tire?

5.5. One axle of the vehicle is equipped with tires of various sizes, designs (radial, diagonal, tubed, tubeless), models, with different tread patterns, frost-resistant and non-frost-resistant, new and reconditioned, new and with an in-depth tread pattern. The vehicle is equipped with studded and non-studded tires.

Within one day you will not be fined.

Many imported cars have a “dokatka”, which looks like a bicycle wheel. You can use both the “dokatka” and any “spare spare” to proceed to the repair site. According to the appendix to the traffic rules “LIST OF FAULTS AND CONDITIONS UNDER WHICH OPERATION OF VEHICLES IS PROHIBITED” operation of the vehicle is prohibited. And even after stopping the IDPS on this issue, you have a day to eliminate this malfunction.

Dmitry-74

Government Russian Federation decides:

1. Approve the attached changes that are being made to the acts of the Government of the Russian Federation.

5.2.3. With the remaining tread depth of winter tires intended for use on icy or snowy road surfaces, marked with a sign in the form of a mountain peak with three peaks and a snowflake inside it (see Figure 5.1), as well as marked with the signs “M S”, “M NOT MORE THAN 4 mm

and in court I can appeal if they fine me that I have 3 mm, but the law clearly states no more than 4??

Dmitry, you took the phrase out of context. This cannot be done in court.

This List establishes malfunctions of cars, buses, road trains, trailers, motorcycles, mopeds, tractors, other self-propelled vehicles and the conditions under which their use is prohibited.

Residual tread depth of winter tires intended for use on icy or snowy road surfaces, marked with a sign in the form of a mountain peak with three peaks and a snowflake inside it, as well as marked with the signs “M+S”, “M&S”, “M S” ( in the absence of wear indicators), during operation on the specified coating is no more than 4 mm.

This point is difficult to understand, especially if you do not read the entire document.

(revision date --- 2 months).

: install the template by tightly pressing the upper stop to the top of the wheel flange, and the side support leg with the stop to the inner edge of the wheel rim.

To measure the thickness of the wheel flange, move the horizontal movable contact to the radius of the flange and use the measuring scale to determine the size of the flange thickness, which should be 25-33 mm at a distance of 18 mm from the top of the ridge.

To measure rolling (uniform and uneven), move the vertical movable contact to the wheel tread and use a measuring scale to determine the amount of rolling, which should be:

(Uniform rolling for the wheelsets of the first bogie of the head car with the stall valve installed --- no more than 3 mm;

Uniform rolling for other wheelsets --- no more than 5 mm;

Uneven rolling for the wheelsets of the first bogie of the head car with a stall valve installed --- no more than 0.5 mm;

Uneven rolling for other wheelsets --- no more than 0.7 mm.

Bore gauge (stikhmass)- to measure the distance between the inner edges of tires or wheel rims (revision period --- 2 months).

To carry out measurements it is necessary: install a fixed contact on the middle of the inner edge of the wheel rim, bring the movable contact to the inner edge of the 2nd wheel of the given wheel pair and with light movements from top to bottom and by rotating the measuring head on the movable contact, bring the tip of the movable contact into contact with the inner edge of the rim of the 2nd wheel. Next, use a measuring scale to determine the distance between the inner edges of the rims of solid-rolled wheels.

(the distance between the inner edges of the rims of solid-rolled wheels should be 1443-1437 mm, at a loaded switchgear deviation at the lowest point is allowed - no more than 2 mm).

Audit period 3 months:

Bracket for measuring the diameter of wheels along the rolling circle of wheelsets(audit period --- 3 months).

Measurements are carried out as follows: install the fixed contact of the bracket on the rolling surface of the wheel, while the moving contact should be slightly above the diameter of the wheel (the stops of the moving and fixed contacts should be tightly pressed to the outer edge of the wheel rim), then with a slight movement of the hand you need to move the moving contact around the circumference until passing the point of the largest diameter (in this case, the stops should not come off the outer edge of the wheel rim). After which the template is removed and the practical diameter of the wheel is determined using the scale on the moving contact. (wheel diameter not less than 810 mm 2;8;12 mm).

Audit period 6 months:

Device for measuring the depth of marks on the axle of a wheelset with a dial indicator(audit period --- 6 months).

To take measurements: install the device on an undamaged area of ​​the axis, set the dial indicator readings to “0” , then move the device on the mark, measure the depth of the mark by the deviation of the dial indicator

--- no more than two blunt transverse or oblique marks are allowed on the middle part of the axis depth up to 0.2 mm no closer than 30 mm from the fillet;

--- no more than two blunt transverse marks are allowed on each axle journal depth up to 0.2 mm no closer than 140 mm from the end of the fillet;

--- no more than two longitudinal marks of depth are allowed on each axle journal up to 0.2 mm no closer than 100 mm from the end of the fillet.

Maximum profile template(audit period --- 6 months).

Used to check the profile of the rolling surface of the gearbox. after turning or upon receipt of new parts. in the electrical depot. When taking measurements: the template must be pressed tightly, without distortions, to the inner edge of the tire or wheel rim; deviations from the template profile are allowed:

--- along the rolling surface no more than 0.5 mm;

--- along the height of the ridge no more than 1 mm.

Template for checking the vertical undercut of the wheel flange(audit period --- 6 months).

To carry out measurements it is necessary: install the template on the wheel, tightly pressing the support leg against the inner edge of the wheel rim, then move the working surface of the engine to the radius of the ridge. Check with a clear light or a feeler gauge for the presence of a gap between the working surface of the engine and the flange at a distance of 18 mm from the base of the flange.

If there is no gap, the wheelset must be repaired.

(vertical undercut of the ridge - not allowed).

Vernier calipers for measuring the width of the bandage(audit period --- 6 months).

To carry out measurements it is necessary: bring the fixed contact of the caliper to

(the width of the bandage should be --- 133 – 126 mm).

Bracket for measuring the diameter of the wheel under the car(audit period --- 6 months).

To measure the wheel diameter without rolling out the wheelset, you must: set the template stop tightly to the inner edge of the wheel rim, install one of the fixed contacts on the wheel tread surface, then smoothly lower the second fixed contact onto the wheel tread surface until it comes into tight contact (while not allowing the template stop to come off from the inner edge of the rim), while observing for changes in readings on the indicator clock (which occurs due to the contact of the movable contact of the indicator clock with the rolling surface of the wheel). Next, the readings are compared with a calculated table of wheel diameter measurements and the practical diameter of a given wheel is found out.

(wheel diameter not less than 810 mm taking into account rental, difference in wheel diameters 2;8;12 mm).

Audit period 1 year:

A device with a dial indicator for measuring a slider

To carry out measurements it is necessary: install the device on the damaged place on the wheel tread surface so that the measuring tip with its tip hits the center of the slider, secure the dial indicator body to the bracket, point the indicator arrows to “0” , then moving smoothly and evenly along the ridge and tightly pressing the support leg of the template to the inner edge of the wheel rim, move the device to an undamaged place, the indicator scale will indicate the depth of the slider (you must remember that the small arrow of the indicator indicates a whole number of millimeters, and the large arrow is a fraction of millimeters (the whole circle of the large arrow is 1 mm)).(slider depth is not allowed -- more than 0.3 mm;

Displacement of metal by height is not allowed -- more than 0.3 mm;

spalling area -- more than 200 mm² and depth - more than 1 mm.

Vernier calipers for measuring the thickness of the wheel rim tire at a distance of 10 mm from the outer edge(audit period --- 12 months).

To carry out measurements it is necessary: bring the fixed contact of the caliper to the inner edge of the wheel rim, while the stop on the caliper should tightly touch the outer edge of the rim (as shown in the photo above), then bring the frame of the movable contact to the rim from the side of the wheel tread, then determine using the measuring scale the thickness of the tire of a given wheel.

(the thickness of the bandage should be --- not less than 30 mm).

Counter template for controlling the profile of the skating circle(audit period --- 12 months).

It is used to check the maximum profile template (the counter template has a profile corresponding to the calculated profile of the wheel tread). When bringing together the template and counter-template (as shown in the photo above), their profiles should be tightly connected and have no gap.

Counter template to the absolute template for measuring rolled stock and flange thickness(audit period --- 12 months).

Used to check an absolute pattern. When bringing together the template and the counter-template (as shown above in the photo), their profiles must be tightly connected and have no gap, the stops must be in close contact, while the moving contact sliders of the absolute template with their tips must clearly touch the corresponding marks on the counter-template, the scale of the movable contact for measurement the thickness of the comb should clearly show the highest value (33 mm, this is shown in the top photo), and the scale of the moving contact for measuring rolled stock should clearly show “0” (as shown in the bottom photo)

Counter template to the template to control the vertical undercut of the ridge(audit period --- 12 months).

Non-contact thermometers “Kelvin”, “Pyrometer”(audit period --- 12 months).

Non-contact temperature meters are used for: checking thermal units in all cases where organoleptic measurements are difficult or the heating of the thermal unit is suspicious, while temperature meters convert the energy of infrared radiation emitted by the surface of the object into an electrical signal, which is displayed digitally on the device screen (as shown in the photo above) . In this case, the emissivity value is set --- 0,86 (which corresponds to --- rubber soft raw (according to clause 6.3 of the Instructions).

All products undergo periodic calibration or testing in accordance with Fed. The Law “On Ensuring the Uniformity of Measurements”.

Responsibility for the maintenance of measuring and control instruments, as well as for monitoring the timing of calibration in the depot, rests with: the foreman in charge of the control room repair area, the foreman of the mechanical department, the foreman of the instrument department, and the metrology engineer.

Measuring instruments must be tested in accordance with PR 50.2.006-94 ”GSI. The procedure for checking measuring instruments” or calibrated in accordance with PR 50.2.016-94 “GSI. Requirements for performing calibration work.”

Types and frequency Maintenance and repair of wheelsets:

The main cause of injuries during the development of trenches and pits is the collapse of soil masses. It occurs due to the absence or insufficient strength of soil fastening when constructing pits and trenches with vertical walls, the presence of unstable slopes, as well as improper dismantling of fastenings. Collapse can also occur after excavation work is completed (during the construction of foundations, pipe laying, etc.).
Cases of collapse of loess soils are especially frequent. While highly durable when dry, when moistened they lose cohesion between the particles, causing loose walls to collapse.
In winter, collapse may occur during development frozen soils. In constant frost, the soils have sufficient strength to adhere to vertical walls. However, when temperatures change and thaws, the strength of frozen soils is impaired, cracks appear, as a result of which loose vertical walls and steep slopes collapse.
Before the start of excavation work at the construction site, geological and hydrogeological surveys are carried out in order to identify the properties of the soil, groundwater regime, etc. In difficult geological and hydrogeological conditions, for example, in landslide and karst zones with high level groundwater, excavation work can only be carried out if there is individual projects performance of work and under mandatory continuous supervision of technical personnel.
On the construction site, all kinds of communications may be located in the ground at various depths: high or low voltage electrical cables, gas pipelines, water supply, sewerage, etc. Therefore, it is necessary to obtain a special written permit (order) for the right to carry out excavation work from those organizations that are in charge of underground communications. The order must be accompanied by a plan with an exact indication of the direction of the route, the depth of the installation, the name and size of communications located within the construction area and indicated by signs (markers).
To clarify the location and depth of underground communications, control trenches or pits must be laid. Workers engaged in this work must undergo labor safety training.
If there are underground communications in the excavation area, work must be carried out with extreme caution, under the supervision of the work foreman or foreman, as well as electrical workers, if work is carried out in close proximity to live cables. In this case, you can use only such mechanisms and tools that cannot damage the laid communications.
Excavation of soil in the immediate vicinity of existing underground utility lines is permitted only with excavation shovels. The use of crowbars, picks, jackhammers and other impact tools in these areas is not permitted.
If any underground communications or structures are discovered that are not shown on the drawings, work must be immediately suspended, the structures or wiring carefully inspected to determine their origin, and the possibility of continuing excavation work must be resolved with the participation of representatives of interested organizations.
During excavation work, there may be cases of harmful gases appearing in pits and trenches. In these cases, work must be stopped immediately and workers removed from dangerous places until the reasons for the appearance and neutralization of the gas are clarified. Only after complete safety has been established can work continue. If there is no complete guarantee that harmful gases will not be released in the future, work should be carried out only if there are indicators for gas detection and if workers are provided with gas masks or oxygen isolating devices that can be used when gas is detected. Before starting work, workers must be instructed on how to combat harmful gases. Smoking and using fire in such places is prohibited, as this may cause an explosion. If ammunition is discovered, excavation work can be resumed only after the site has been inspected and the ammunition has been removed by sappers.
Digging pits and trenches with vertical walls without fastenings is only possible in soils with an undisturbed structure, natural moisture in the absence of groundwater and nearby underground structures. Under these conditions, the depth of recesses without fastenings according to SNiP 111-4-80 should not exceed:
- 1 m - in sandy and gravel soils;
- 1.25 m - in sandy loam;
- 1.5 m - in loams, clays, dry loess-like soils.
Under all other conditions, trenches and pits must be developed either with slopes or with vertical walls fixed to the full height.
Digging trenches with vertical walls without fastenings using rotary or trench excavators in dense cohesive soils is allowed to a depth of no more than 3 m. However, workers are not allowed to go down into the trench, as the vertical walls may collapse. In areas of the trench where workers are required, fastenings or slopes should be installed.

Pits and trenches in frozen soil can be dug without fastenings only to the freezing depth. It is not allowed to carry out excavation work in winter by digging and tapping. Overhanging canopies, stones and boulders must be brought down.
The condition of dug trenches and pits with vertical walls must be constantly monitored by construction technical personnel. If signs of wall collapse are detected, it is necessary to urgently take measures to ensure the safety of workers: install local fastenings or collapse the soil in a dangerous place.
In soils with a disturbed structure with a high groundwater level, the presence of underground communications, and also at a depth of more than 2 m, the vertical walls of pits and trenches must be secured.
The fastening of pits and trenches with a depth of no more than 3 m should, as a rule, be made using inventory. It is installed in accordance with standard projects. Types of fastenings may be different. Their design depends on the properties of the soil, the depth of the trench and the loads acting on the fastenings.
The following types of fastenings for the vertical walls of pits and trenches are used:
- in soils of natural moisture, with the exception of loose ones, - horizontal fastenings with clearance through one board;
- in soils of high humidity and loose - continuous vertical or horizontal fastenings;
- in all types of soils with a strong influx of groundwater - sheet piling, driven to a depth of at least 0.75 m into the underlying waterproof soil (below the groundwater horizon).
For pits and trenches with a depth of more than 3 m, the type of fastening, design and dimensions of its elements must be determined by calculation and provided for in the work design.
When digging trenches and pits with earth-moving machines, the vertical walls are secured immediately to the designed depth with ready-made shields, lowered and secured from above. In this case, workers should not be allowed into an unsecured excavation.
The development of excavations in soils saturated with water (quicksands) is carried out according to individual projects, providing for safe methods of work, artificial water lowering, sheet piling, etc.
When developing pits and trenches with fastenings, areas adjacent to previously filled excavations where the soil structure is disturbed are particularly dangerous. Here the supplied fasteners can become deformed and destroyed. Therefore, it is necessary to systematically monitor the condition of the fastening in order to eliminate deformations, especially in areas with heaving soils, and with the onset of frost or warming, daily checks are necessary, recording the results in the work log. Fastening material should be fed into trenches using mechanical means. Disposing of materials into pits or trenches, regardless of their length and weight, is not permitted. All fastenings installed in winter must be inspected upon the onset of a thaw and, if necessary, strengthened. Pits and trenches in which fastenings were removed in winter or which were developed without fastenings must be secured when warm weather sets in. Excavations in water-saturated soils are developed by freezing in sections, leaving between them partitions of frozen soil at least 0.5 m wide. When working in frozen and rocky soils, workers are provided with special goggles with a mesh.
The design of fastening the vertical walls of pits and trenches up to 3 m deep must be inventory. Fastening is carried out according to standard designs. The use of inventory fastenings provides for: prefabrication of elements, the possibility of installing them from above, mechanization of installation and disassembly of panels. This contributes to the safety of work in trenches, can significantly reduce labor costs, ensure multiple turnover of fastening equipment and ultimately reduce construction costs.
In cases where there are no standard inventory parts for fastening pits and trenches up to 3 m deep, they should be fastened taking into account certain requirements.
To fasten soils of natural moisture (except sandy), you need to use boards with a thickness of at least 4 cm, and for sandy soils and high humidity - at least 5 cm, laying them behind the vertical posts as they go deeper, close to the ground, reinforced with spacers.
The fastening posts are installed at a distance of 1.5 m along the excavation in pairs and secured with horizontal struts. Spacers are installed at a distance of no more than 1 m vertically from one another. The spacers are secured with special parts - bosses, which prevent the spacers from moving. The bosses are fastened (top and bottom) with nails no less than 125 mm long.
The upper fastening boards above the edges of the excavations (side boards) are extended at least 15 cm. This is done in order to avoid accidental falling of discarded soil, stones and other objects into the excavation.
A cleared strip of at least 0.5 m wide is left on each side of the trench. It is intended for the passage of workers, as well as for the temporary placement of discarded soil and the laying of materials for fastenings. The edges of the pit must be kept clean. Store a large number of materials or soil is permitted only outside the collapse prism. It is prohibited to store materials at ramps, in pits and at workplaces.
To lower workers into pits and wide trenches, stepladders at least 1 m wide with railings are installed. It is prohibited for workers to descend along the support struts.
When backfilling pits and trenches, dismantling the fastenings should not be done immediately to the full height, but in parts. In this case, you need to disassemble and remove the board fastenings carefully in the direction from bottom to top as you backfill. The number of simultaneously removed boards in height should not exceed three, and in loose or unstable soils - one. When removing boards, spacers should be rearranged accordingly, and existing ones can be removed after installing new ones.
Dismantling of fasteners is carried out under the supervision of shift technical personnel (work foreman or foreman).
One-sided backfilling of trenches and pits with freshly laid retaining walls, basement walls and foundations is possible only after checking the stability of the masonry by calculation and achieving the design strength of the solution.
When constructing underground structures outside the immediate vicinity of existing adjacent objects (pipelines, building foundations, etc.), pits or trenches must be backfilled without dismantling the fastenings, since their disassembly can lead to breakdowns and accidents. You should also not disassemble fastenings in recesses dug in loose soils or quicksand, if this may lead to the collapse of the soil and damage to nearby structures. In these cases, the fastening must be partially or completely left in the ground. In cases where the project provides for the development of pits and trenches of great depth, it is advisable to carry out it with slopes without fastenings.
When developing soil with slopes, first of all, it is necessary to determine the steepness of the slopes, ensuring the safety of developing this soil, and also to choose the method of forming the slopes. The steepness of slopes in excavations depends on the type of soil, humidity and degree of loosening, as well as on the depth of the excavation and the nature of the soil and is determined by the angle between the direction of the slope and the horizontal.
SNiP III-4-80 provides for the highest permissible steepness of slopes of pits and trenches with a depth of up to 5 m, defined as the ratio of the height of the slope to the foundation (see table).

Permissible slope steepness of excavations

Note. When layering various types soils, the steepness of the slopes for all layers should be assigned according to the weakest type of soil.
When the excavation depth is over 5 m, the steepness of the slope is determined by calculation and indicated in the design. An increase in the moisture content of some types of soil significantly changes their stability on slopes, and the angle of natural repose decreases. Therefore, in waterlogged clay soils, the steepness of the slopes should be reduced to 45° or to a ratio of 1:1. The change in the steepness of the slopes is recorded by the work contractor in the appropriate act.
When developing waterlogged sandy, loess and bulk soils, fasteners are installed.
The condition of the slopes of pits and trenches developed with slopes (without fastenings) must be systematically monitored. For this purpose, the workman or foreman, before the start of each shift, is obliged to check the condition of the slopes and immediately take measures to collapse or strengthen the soil in those places where peaks or cracks are found.
If there is a danger of ground collapse, it is necessary to temporarily stop work. They can be resumed only after the danger has been completely eliminated. It is also advisable to prohibit the movement of vehicles and mechanisms within the soil collapse prism.
When working on slopes of excavations and embankments with a depth (height) of more than 3 m and a steepness of more than 1:1, and when the surface of a slope is wet with a steepness of 1:2, workers are equipped with safety belts attached to reliable supports.
When digging trenches, pits and wells in areas of heavy human traffic (streets, courtyards, squares), strong fences with a height of at least 1.2 m with warning signs are installed around the work site at a distance of 0.8 - 1 m from the edge. At night, the fences are illuminated. It is recommended to install side boards at ground level at the edge of a trench or pit. Open pits and trenches near roads and residential buildings are fenced with a solid fence. To cross trenches, bridges are installed with a width of at least 0.8 m for one-way traffic and a width of 1.5 m with railings at least 1.2 m high, a side board and barriers for two-way traffic. At night the crossing is illuminated.
The development of excavations in soils saturated with water (quicksands) is carried out according to individual projects that provide for safe methods of carrying out work (artificial dewatering, sheet piling, etc.).
Groundwater is removed by open drainage or deep dewatering. Open drainage using pumps is used for rocky and large-block soils (crushed stone, pebbles, gravel). Open drainage in sandy and sandy loam soils leads to the sliding of slopes and loosening of the foundation, therefore, in such soils, deep dewatering is used with the help of wellpoint installations.
Work on the installation of drainage, dewatering or a combination thereof is permitted only if there is an approved dewatering project linked to the production project construction work. Before the installation of water-reducing installations begins, the breakdown of: wells is carried out; routes of suction and pressure communications; power lines; locations of drainage trays and pumping units. Buildings and structures located in the immediate vicinity of water-reducing installations must be inspected, and their condition recorded in an act. The pumped water is discharged at least 100 m from the excavation. The discharge of water into existing drains is agreed upon with the relevant organizations operating them. Suction manifolds and wellpoint pumps are located at the lowest possible elevations. To do this, before installation of the installations begins, the soil located above groundwater should be removed. When installing pumps, suction and pressure communications, the tightness of all connections must be ensured. The suction manifold of wellpoint filter units is laid on pads on a planned surface with a slope from the pump of 0.005 - 0.02.
Work on artificial dewatering of groundwater can begin only after production testing of equipment and communications by turning on one or a group of filters one by one. During operation of the water-reducing installation, systematic monitoring of the decrease in water level in monitoring wells is carried out. Water is pumped out of the filters continuously, which is ensured by backup pumping equipment with power supply from two different sources.
Water-reducing and drainage installations are accepted by a commission appointed by the head or chief engineer of the construction organization, which is documented in an acceptance certificate. In this case the following must be presented:
- control geological sections confirming preliminary survey data;
- executive diagrams of water-reducing wells and wellpoint installations;
- pipeline testing reports;
- reports on the operation of the water-reducing unit during a trial run;
- acts for hidden work.
In open drainage, groundwater is pumped directly from a pit or trench as it is being developed.
The disadvantage of open drainage is that the water entering through the walls of the pit removes soil particles from them, and moving to the bottom of the pit loosens the soil and reduces its bearing capacity. Open drainage at critical structures can be used in cases where sheet piling is clogged along the perimeter of the pit. To avoid damage to the foundation, water is pumped out through a receiving well, which is buried 0.5 m relative to the surface of the excavated soil.
Ground drainage is used in cases where the rock being drained has sufficient water permeability (characterized by the filtration coefficient). In ground drainage, water is pumped out from tubular wells located in a certain order and connected by a common suction pipe. With constant pumping of water from a system of such wells, the natural groundwater level must be brought to 0.5 m below the bottom of the pit, while water flows to the well from top to bottom along the depression curve. This method leads to soil compaction. The pumped water is discharged at least 100 m from the excavation. The discharge of water into existing drains is coordinated with the relevant organizations.
It is recommended to carry out deep water reduction at construction sites using water reduction units with lightweight wellpoints of the drainage collector and a pumping unit. Under the influence of the difference between atmospheric and low pressure in the communications of the water-reducing installation, groundwater enters wellpoints, fills the suction collector and is pumped into storm water intakes or outside the drainage area. The suction manifold is mounted from pipes with branch pipes for connecting wellpoints. The distance between wellpoints depends on the soil filtration coefficient and is 0.75 m for small coefficients, and one or two pipes for large coefficients, i.e. 1.5 - 2.25 m.
Before starting the wellpoint unit, the pump unit must pump out air from the suction system. You can open the valve to pump out water only after the vacuum gauge shows that there is no air coming from the system. It is prohibited to remove installed wellpoint filters using truck cranes. Wellpoints should only be removed using needle pullers, mechanical or hydraulic jacks. When immersing or removing wellpoints, no people are allowed within a radius of one and a half lengths of the wellpoint.
The most common and effective machines used for mechanizing excavation work are single-bucket excavators. Before starting work within the construction site, the paths along which excavators will move are prepared: the soil is leveled and leveled, the path on soft soils is reinforced with shields, flooring made of boards, beams or sleepers. Moving an excavator over artificial structures (bridges, pipes under embankments, overpasses, etc.) is allowed only after a preliminary check of the strength of these structures and obtaining permission for the excavator to pass through the structures from the organizations in charge of them. While the excavator is moving, its boom should be installed strictly in the direction of travel, and the bucket should be raised above the ground by 0.5 - 0.7 m. It is prohibited to move the excavator with a loaded bucket.
If the angle of inclination of the terrain is greater than that established by the passport data, the excavator is lowered and raised using a tractor or winch in the presence of a mechanic, workman or foreman.
After the path is prepared and the excavator passes to the work site, soil excavation begins in accordance with the technological map and the work project. To avoid spontaneous movement, excavators are secured with portable supports during operation. It is prohibited to place boards, logs, stones or other objects under the tracks or rollers to prevent the working excavator from moving.
While the excavator is operating, workers are prohibited from standing under the bucket or boom. It is forbidden to carry out any other work from the face. They can only be carried out outside the danger zone, which is determined by the radius of action of the excavator, increased by 5 m. Particular attention should be paid to ensuring that there are no power lines within the radius of action of the excavator.
The excavated soil should be loaded onto vehicles with an excavator from the rear or side of the vehicle. The width of the ramp into the pit is determined by the dimensions of vehicles - dump trucks or other vehicles used in construction, and passages for people at least 1 m wide on each side of the ramp. When loading soil between the earthmoving machine and vehicles there were people.
During breaks in work, regardless of their reasons and duration, the excavator boom should be moved away from the face and the bucket lowered to the ground. The bucket should only be cleaned by lowering it to the ground.
In cases of temporary cessation of trenching work or when repairing an excavator, it must be moved to a distance of at least 2 m from the edge of the open trench. In this case, it is necessary to place pads on both sides of the tracks or wheels.
Some types of excavation work have to be performed with tractor scrapers. To avoid the machine tipping over, you must not approach the slope of the excavation at a distance of less than 0.5 m and the slope of a freshly poured embankment at a distance of less than 1 m. When excavating soil simultaneously with several scrapers, a distance of at least 20 m must be maintained between them in all cases, since with a smaller interval the scraper driver will not be able to brake the car if the scraper in front stops arbitrarily.
When working with a bulldozer, it is prohibited to move soil uphill or down a slope of more than 30°, as well as to extend the bulldozer blade to the edge of the excavation slope (when dumping soil). If large stones, stumps or other objects are found in the excavated soil, the machine must be stopped immediately and everything that could cause an accident must be removed from the path, and only then work can continue.
Excavation work using hydromechanization is carried out only if there is a work plan, which must provide for the sequence of work and auxiliary devices for its safe execution. The territory where excavation work is carried out using hydromechanization is fenced. The working area of ​​the hydraulic monitor is additionally marked with warning signs. The hydraulic monitor must have a passport indicating the permissible operating pressure and a pressure gauge installed on its barrel. Before starting work, the hydraulic monitor is checked for pressure exceeding the working pressure by at least 50%. During the work process, this pressure is not allowed to increase. A valve is installed on the working water pipeline at a distance of no more than 10 m from the hydraulic monitor operator’s workplace, which would make it possible to instantly stop access to water in emergency cases. Reliable telephone communication and emergency signaling equipment are installed between the pumping station and the hydraulic monitors in the face. Troubleshooting the hydraulic monitor, clearing debris, changing nozzles, tightening flanges and pipe couplings is carried out only with the valve closed or after the water supply has been stopped. All areas of work - the area of ​​effect of the jet of the hydraulic monitor, the working area near it, the path to the valve that shuts off the water and the valves themselves - must be illuminated at night.
Freshly washed soil is fenced off with dams or shields with safety signs prohibiting human access. Walking on washed-up soil is allowed only after it has been compacted to such an extent that walking on the ground becomes safe. To access the devices that drain water from the alluvium area, bridges with railings are installed. All wells are covered or fenced off.
The panel is assembled using a previously developed and approved installation technology that ensures safe work at different levels. Driving underground tunnels and sewers with shields less than 2 m in diameter is not permitted. The lowering of panel elements into the shaft is carried out under the direct supervision of a site mechanic or work foreman only if there is a working alarm. Signals are given by a specially designated person from among the workers involved in the descent.
Excavation of soil in the faces during shield tunneling is allowed only within the shield canopies. Wherein:
- the mounted shield, its mechanisms and accessories may be put into operation only after they have been accepted by the commission under the act;
- it is prohibited to move the shield to a distance exceeding the width of the block lining ring without fixed blocks, and to develop soil outside the inner perimeter of the shield;
- outside stable weak soils, the face of the face must be secured with temporary support with sanders, and in sandy loose soils it is necessary to use shields with horizontal shelves;
- moving the shield is allowed only in the presence and under the guidance of the shift foreman or the work foreman and the duty mechanic;
- it is prohibited for people to stay at the face while moving the shield, with the exception of workers monitoring the fastening.
The voids behind the block lining formed during the passage are filled by injecting cement-sand mortar. When laying blocks, the master must carry out a preliminary (template, lath) and the surveyor must carry out an instrumental check of the ellipticity of each ring with a diameter of 2.5 m or more. If ellipticity of the lining is detected (exceeding the permissible level), special fastening rings and racks are immediately installed.
During welding work, supply and exhaust ventilation is installed in tunnels. The content of harmful impurities in the air is monitored at least once per shift.

Minimum tire tread height on a car - 1.6mm. This indicator is adopted by the International Tire Manufacturers Association. When rubber wear reaches a critical level, the tread reaches the limiters.

In Ukraine, this parameter is in the form of a recommendation from State SpozhivStandard (DSTU3649 - 2010). The law has not yet been adopted.

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6.3.2 The height of the tire tread pattern should correspond to the values ​​​​given in table 7. "

Fragment from "Vimoga for the safety of technical equipment and control methods DSTU 3649:2010"

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As wear progresses, the limiter becomes comparable to the tread.

There should be a minimum of 1.6mm across the entire width of the working part. IN In any part of the working area, the depth must be no less than the standard.

depth is measured across the entire tread width

Wear should be even across the entire circumference of the tread, without sharp dents or irregularities. A tire with uneven wear is not suitable for use.

In the field of car enthusiasts, there is an opinion that limiters in order to change and buy new tires more often...

It's a delusion.

The limiter warns that driving on these tires is dangerous. Numerous tire tests with a tread less than 1.6mm show long braking distance on a wet road.

Turns on aquaplaning effect , exposing danger life driver and passenger.

Winter tire tread depth indicator

The optimal tread depth for winter tires is greater than for summer tires. Compacted snow is more difficult to remove from the wheel contact patch, so the grooves must be deeper.

For winter tires the depth is 4mm , we note that this is RECOMMENDED value .

Legally Required The tread height of winter wheels is the same as for summer wheels- 1.6mm .

Tire tread depth for jeeps and SUVs

On Japanese winter tires for jeeps (popularly “Velcro”), in addition to limiters, there is indicator 50%, which IS NOT A LIMITER .

It shows a layer of active sticky rubber on the tread. After it comes a layer of simple winter tires.

The height of the indicator in millimeters is not fixed and depends on the tread depth of the new rubber. New Jeep tires can have from 11mm to 15mm depth.

Photo: despite the fact that the Velcro has worn off (the 50% indicator is equal to the tread), the depth of the grooves remains large

To avoid searching for a limiter on the tread for a long time, some manufacturers put indicators on the sidewall. For example, GoodYear came up with an interesting sign in the form of a Snowman with an arrow.

How and how to measure tire tread depth

There are three verification methods:

1) Accurate

2) Not accurate

3) By eye

1) The tread gauge is a precision tool. There are electronic and mechanical. Small, you can put it in the glove compartment or in your clothing pocket.

It works like a caliper, place the gauge on the tread so that the needle is in the center of the drainage groove, and lower it all the way. ALL. The result is on the scoreboard.

simple pocket tread gauge

electronic depth gauge

Measure the tire depth once a month, in several places, to diagnose uneven wear in time.

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