In which project the width of the trench is indicated. Sizing the pit. Calculation of technical parameters and the choice of excavators
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The width of the trench along the bottom with a pipe diameter of up to 700 mm should be 0 3 m more than this diameter, and with a larger diameter it is taken equal to one and a half diameters. When ballasting with loads, the distance between the wall of the trench and the load should not be less than 0 2 m, and the width of the trench along the bottom should not be less than 2 2 diameters.
The width of the trench for steel pipes is taken from the condition of laying them along one pipe and welding the joint at the bottom of the trench.
Durability There are a number of specific properties that affect the durability of a product. The strength of the pipe depends on the materials used in the concrete mixture, such as aggregates, cement material and additives. It also depends on the mixture design, manufacturing methods and curing process.
Water absorption is mainly used to check the density and impermeability of concrete used in reinforced concrete pipes. Water absorption can be highly dependent on both the aggregates and the manufacturing process used. Alkalinity is affected by the cement content in the mixture and includes both cement and fly ash. The key to high alkalinity and proper cement content is the development of the mixture, taking into account all the material properties used, as well as the production and curing processes.
The width of the trench for prefabricated reinforced concrete and brick collectors depends on how they are laid and sealed. During the construction of brick canals, the outer walls of the canal chair are laid close to the inner walls of the trench. Then the width of the trenches will be equal to the width of the channel to the outer size.
The width of the trench is determined by the number and type of cable lines being laid, the permissible distances between them, as well as the technical data of the excavation mechanism used.
Units are a key element in the production of high-quality concrete and, in turn, high-quality pipes. With regard to strength, durability and performance, all aspects of the units should be considered. These include gradation, absorption, specific gravity, hardness, and in some cases alkalinity.
This means indicating the pipe for proper use in a specific environment, manufactured with good quality control, with experience and healing correctly and thoroughly. If you need to dig a trench along a narrow strip of land between two buildings, you have two options. A hardworking worker may be able to impress on the speed and accuracy of the manual trench, but where there is room for work, the compact trencher can cope with significant time and money savings.
The width of the trench at the bottom mark is 0 3 - 0 5 m, and at the top 0 8 - 2 5 m, depending on the angle of repose of the soil. The length of the trench is determined by the number of electrodes installed. In the case of using coke backfill, it is placed in an even layer with a thickness of 0 1 m along the bottom of the trench. This layer is leveled and rammed.
The width of the trench (at the bottom) for laying one or two cables is 350 mm, and with a larger number of cables it increases by 150 mm for each subsequent cable. When laying the cable in the ground, it is necessary to provide a margin of 3% of the total cable length and arrange it evenly along the entire length, laying it with a snake. When withdrawing armored and unarmored cables to the surface from a trench, it is necessary to protect them from mechanical damage up to a height of 2 m from the ground level, and when entering cables from trenches into a building through a protective pipe, measures should be taken to prevent water from entering trenches into the building. Cables laid in the ground are indicated by special signs, fixed on the walls of the nearest buildings or on poles.
Before dipping a site, you must do one without exception: Indicate the location of existing underground engineering lines and mark it before the trench. Don't you think you need to call? Let me put aside my pride and tell you a story.
Designing the pit and determining its main dimensions
Fortunately, the trencher was not injured. Having spent nearly a thousand of my own dollars to set up a new subpanel, my customers became electricity again. One five-minute phone call could bring us a lot of grief. Trench Anatomy The two main types of compact trenchers are to ride and walk. Walking blocks are smaller and more suitable spaces. Most trenchers of any type have three main operating systems.
The width of the trench at the bottom for cables up to 10 kb is: 350 mm, for one or two cables; 600 mm for three; 650 mm for four. If there are more than five cables, the width of the trench along the bottom increases by 120 - 130 mm for each subsequent cable.
The width of the trench (bottom and without fixing) when laying pipes should be 0 5 m greater than their diameter, if the latter is not more than 0 5 m; when laying pipes in the channel, the width of the trenches is taken to be 0 2 m more than the width of the channel.
In addition, cars vary greatly in number and complexity of options. Your choice includes the type of chain and boom control, digging depth and width, power, safety features and many other options. Some of the simplest compact trenchers are disk trenchers or, as some manufacturers call it, saws for earthworks - use a rotating disk with a rotating engine with digging teeth. They usually produce narrow, shallow trenches, so their use is limited to smaller applications.
The width of the trench (bottom and without fixing) when laying pipes should be 0 5 m greater than their diameter, if the latter is not more than 0 5 m; when laying pipes in the channel, the width of the trenches is taken to be 0 2 m more than the width of the channel. Cast-iron pressure pipes are laid forward with bells (with respect to the street network); the joints are closed up, filling the annular gap with a hemp tarred rope and then the remaining annular space is filled and minted with asbestos-cement mortar.
However, they are suitable for small pipelines, as well as for some wired connections, and their price and size make them economical for small applications. If you purchase a trencher, carefully evaluate the options available to you and compare them with the usual trench requirements and your budget.
The right machine for work Regardless of whether you rent a car or simply select it according to your "stable" characteristics of the site and the required size of the trench, largely determine the type of trencher that you will need for a particular job.
The width of the trench is determined by the number and type of cables laid and the permissible distance between them. To lay one cable for voltage up to 10 ke, the width of the trench should be 350 mm, with its further increase by 120 - 150 mm for each subsequent cable.
The dimensions of the pits are determined based on the overall dimensions of the structure in terms of its depth, the steepness of the slopes, as well as the accepted methods for performing the basic production processes. It is important to take into account: the construction scheme of the future structure, which determines the movement pattern of cranes and other machines when assembling prefabricated or erecting monolithic structures; delivery and layout of structures in the installation area, installation of formwork, scaffolding and scaffolding. Since in the construction of water supply and sanitation systems, recessed and most often capacitive structures are built in a rectangular or round shape that actually differ from each other only in their sizes and internal structural elements, then regardless of their purpose and accessory (but taking into account the general dimensions of the structures) identify the following four main schemes for their construction: SchemeI (ring) -crane and vehicles during the construction of the structure move around it along the berm of the pit, not dropping to its bottom; schemeII- mechanisms move along the bottom of the pit outside the structure, along its perimeter; schemeIII - mechanisms in the process of construction of a structure move directly along its bottom; schemeIV provides for the installation of the structure at the same time, i.e., in parallel with two cranes, in which the structures of the extreme degrees of the adjacent span of the structure are mounted with the first crane with the movement of it and vehicles along the berm of the foundation pit, and the structures inside the structure with the second crane moving along the bottom of the structure.
Calculation of technical parameters and the choice of excavators
If you are working on a new site, access is usually not a problem. Therefore, none of them is the size of your trencher. However, communication is important. Make sure project managers and other contractors are aware of your access needs and time frames, and that they can build access to your equipment.
If you are working on a constructed property, you may need to remove part of the fence or wall to access the site. If you can, try rebuilding part of a remote fence or wall as a gate or access panel to facilitate future access needs.
Schemes for determining the size of pits and trenches:
a- pits of small size c. plan (In Soor<15м); b- the same, medium (In Soor\u003e 15 m);
in- the same, large (In sooo, 3\u003e 15 m): g- trenches with vertical walls and fixtures;
d- trapezoidal; from- complex cross-section with combined laying of pipelines
Compact trenchers, as the term suggests, do not need a large room for access. Although cars vary in width, the average walking width is 36 inches wide. A 48-inch wide access track provides a comfortable room if you need to make sharp turns. In contrast, most seated trenchers need 60 inches or more for comfortable access.
Determination of the main dimensions of the pit
Mini loaders are becoming more and more popular with landscape installers. These machines are designed to receive various devices, including trenchers. They can be small steering wheels, or they can be controlled using a track. In any case, their narrow width - several mini loaders from 36 to 40 inches wide, if equipped with narrow tires - they are suitable for many bottlenecks where you use a tracked trencher.
Scheme I usually erects small structures, the width of which in plan or diameter does not exceed 15 m. The dimensions of the pit (width IN to and length Lк) are determined on the basis of the external dimensions of the structure with slight broadening
its bottom on each side for ease of work (Fig. a): Bk \u003d Vsoor + 2b, Lk \u003d Lsoor + 2b, where Scoop, Lsoor - the width and length of the erected structure along the outer perimeter; b - the width of the free space between the bottom of the slope of the excavation and the protruding part of the bottom of the structure (accepted according to the safety conditions and the convenience of work of at least 0.5 m). According to Scheme II, structures of medium dimensions are being erected, the dimensions of which in plan exceed 15 m with a significant depth and a large mass of mounting elements. The dimensions of the pit should be sufficient for the placement of structures, as well as for the passage of cranes and vehicles around them along the bottom of the excavation (Fig. b)and for the layout of prefabricated structures on the front of work:
The required depth and width of the trench is determined by two main factors: the codes of the trenches of the trenches and the size of the pipeline or pipeline. Remember that you will need a trench slightly wider than the pipe you will be working with so that you have a place to work with fittings in the trench. Many factors determine the correct trench depth, and local codes may require a certain minimum depth. However, for most landscape applications, almost all trenchers can reach the required depth.
Even small disk trenchers can dig to a depth of 10 or 12 inches, sufficient for a small sprinkler pipe and some wired applications. Obviously, the depth and width of the trench depends on the machine. Most tracked trenchers can cut trenches from 5 to 12 inches wide and up to 48 inches deep. Train trenchers can cut trenches up to 16 inches wide and 60 inches deep.
B K \u003d D H n + (n-l) B 2 + 2B 3; L K \u003d D a n 1 + (n 1 -l) B 2 + 2B 3, where D H - the diameter or size of the structure along the outer perimeter; pand n 1 - the number of structures or sections in one row, respectively, in the transverse and longitudinal directions; IN 2 - distance between structures in the light; IN 3 - broadening of the pit along the bottom for the safe implementation of installation work and traffic; B 3 \u003d\u003d 2 (1 + R), where 1 is the clearance between the moving crane and the structure (or slope of the excavation), m; R- radius of rotation of the crane machine platform.
Fortunately, places where you need a compact trencher, such as residential work, are also usually the ones where the small bandwidth of the compact trencher is sufficient. However, it is always better to have a little more trench than you think you need. If nothing else, this may allow you to do the work faster.
Operation As with all field operations, trenches work best when you plan to move forward. Make a place for equipment, chalk or paint the necessary paths of the trench, leave a lot of space for turning the machine and, if possible, try to avoid tight turns.
When constructing structures from monolithic reinforced concrete, the dimensions of the pit are determined by the same formulas, only with the addition of IN to and L K double value 2 b op - the width of the formwork unit or the fastening of stationary formwork and scaffolding at the level of the bottom of the pit). Under Scheme III, large structures are usually built ( in),whose dimensions in the plan are several times greater than 15 m. In this case, the dimensions of the pit are equal: Bk \u003d Vsoor + 2b + B 4, Lk \u003d Lsoor + 2 l 1 where IN 4 - broadening of the pit for the installation of structures of the last section of the structure (pic in);l 1 - broadening of the pit at the ends of the structure for entry and exit of the crane and vehicles (taken equal to 6 .. .7 m and depends on the radius of their rotation); B 4 \u003d 1 · 3 + 2R m + Ba, where B a - the width of the truck base at the body level (size). Under scheme IV, large structures are built at IN soor \u003e 15pm. The dimensions of the pits, since the broadening of their bottom by IN 3 or IN 4 not required, can be determined by the formulas used in scheme I. The dimensions of the pits on top IN to in and B to in determined based on their size down IN to , L to , digging depths H and accepted slope ratios t for appropriate soils. Trench Sizes. The smallest trench width along the bottom of Bt.min (according to SNiPu) should be taken depending on the type and diameter of the pipes being laid, and the method of laying them. The width of the trenches along the bottom with a pipe diameter of over 3.5 m, as well as on curved sections of the route, is set by the project. The width of the trenches with slopes (Fig. e)at the bottom it is taken equal to D + 0.5 m when laying pipelines from individual pipes and D + 0.3 m when laying with lashes. When mounting fixtures (Fig. d)the width of the trench is increased by their thickness. If work of people is necessary in trenches with vertical walls, the smallest distance in the light between the surface of the pipeline (collector) and the walls should be at least 0.7 m. The width of the trench on top is determined by the steepness of its slopes. The depth of the trench depends on the depth of the pipe, which in all cases should be 0.5 m more than the estimated depth of freezing of the soil. The longitudinal slope of the trench is set by the project depending on the purpose of the pipeline. To seal the butt joints of pipes in trenches, pits of the required size are torn off.
Once you are in place, start the machine, fold it away from the trailer and move it into place using the ground transportation system. The field movement of the machine is best done with the boom and digging chain in front and transmission forward. trenches are most effective when the machine pulls an arrow and digs the chain with the gearbox in the opposite direction.
On a flat surface and in erratic soil, trenchers can be well tracked on their own, but you may need to sometimes push them sideways to keep them in line. On a slope, you may need to provide almost constant lateral pressure to achieve an acceptable trench. Do not tie the chain into the trench with excessive pull or push, and do not strain your body. Stretch out before you start using the machine and keep your knees bent while you work. Fortunately, most plastic pipes and tubing are flexible, allowing you to “snake” it through trenches.
