Vertical layout of the construction site. Vertical construction site layout Performing vertical layout
The vertical layout of the construction site is part of the preparatory period in construction. Vertical layout is an artificial change in terrain according to project data.
The site obtained as a result can already be used for further work. Prior to all building processes, it is necessary to obtain permission to produce work and only then begin the development of the territory.
The layout of the construction site is carried out by cutting the soil and submits to it in the required volumes and places. It is a mandatory component before the construction of the facility.
The development area is aligned, minor slopes are arranged, serving to remove rain and melting precipitation from the construction site.
If necessary, additional earth structures are arranged - drainage or drainage drangum, embankments, other. They prevent the admission and accumulation of atmospheric water to the construction site from the neighboring territories.
Main steps of vertical layout
Vertical layout must be performed with maximum preservation of natural terrain. When calculating, operating the smallest volumes of earthworks.
In this case, the proper preservation of the fertile soil layer where it is possible. If this can not be done, the humus layer of the soil is removed and moved beyond the construction site. Subsequently, the cut layer will go to the landscaping of the territory.
Performed to prepare a plot for development. It is the initial part of the construction plan.
The execution of vertical layout can be conditionally divided into several stages:
- Removal and movement of the vegetable layer of the soil;
- Development of earthmashs by cutting in bulk and moving them into existing excavations;
- Running the design embankment and soil compaction;
- The final layout of areas and slopes in bulk and notches.
Depending on the ground conditions (a high level of subspeted waters, weak soils, other) planning achieved and solving other tasks.
For example, building a mound (ground pillow) for the future structure, it is possible to ensure the location of the foundations above the level of the rod water. This makes it possible to build where it has not been possible earlier.
The drawings of the vertical layout are included in the section of the set of work drawings of the master plan, which includes:
- Summary of work drawings;
- Plan to landing structures on the ground;
- Plan of the projected relief (slopes, horizontal, zero marks of structures, other);
- The plan of the moved masses of the soil (excavation, mound);
- General Plan of Engineering Communications;
- Plan of landscaped area (roads, sidewalks, small architectural forms).
Being part of the territory of the territory, the vertical layout solves certain tasks:
Organizes the drain from the construction site - storm, rain, melt waters;
Solves the task of planting buildings, structures, laying underground communications with the smallest of earthworks;
Provides permissible slopes of streets, travel, sites, sidewalks to move in safe mode of vehicles, pedestrians;
Organizes the projected relief;
We will not be emphasized that in, the production of work (pos, PPR) there are requirements for the planning of the construction site.
Properly performed vertical layout of the construction site is necessary for the accurate installation of arrows and tower cranes. As well as forests and scaffolding on facades of buildings, the right storage of building materials and structures.
Geodesic work on vertical layout
The vertical planning project project is developed by the project company specialists. There are two main types of development of vertical layout projects.
- Design of horizontal territory with the preservation of the balance of earthlings.
- Design of inclined sites.
The balance of earth mass is a condition, in which the difference between the volumes of cutting and underdevelopment of the soil should be as close as possible to zero.
If the volume of the soil extracted in the development of recesses can be laid in the mound, which is built on the construction site, the balance is called zero.
This option can be called optimal, as it will not require additional expenses for the development of soil, its loading and transportation.
When designing the basis, the existing topographic surface of the construction site is taken. In general, the most simple and common is the following technique.
A geodesic survey (leveling) of the construction site on the square grid is performed. The side of the square is taken from 10 to 100 meters.
The vertices of the squares are marked on the areas of the spicy. Based on the topographic shooting of vertex marks of the squares, the design mark of the planned (horizontal) construction site is calculated.
Then the working marks of the intersections of squares are calculated (plus - to plug, minus - cut), as well as the position of the places and the zero lines. After that, the volume and cartographer of earth mass is calculated.
A similar technique is used in the design of inclined sites. The vertical layout of the construction site is already performed already taking into account the specified shock project.
Perform vertical layout
The preparatory activities include work on cleaning the construction area from trees, bushes, stumps, boulders and other things.
In addition, the removal of surface waters, drainage of the territory, the breakdown of the construction site for the production of planning activities, the cutting of the vegetable layer of the soil.
Main works:
- The development of the soil in places where it must be cut off with moving to the place where it must be added;
- Running, sealing it in bulk;
- Removal or removal of earth mass on the construction site if necessary;
- Final is the site layout.
Vertical layout is carried out using earthmoving machines. With minor work, bulldozers are used small and medium power.
When moving the soil at a distance of 80-100 meters - bulldozers of high power or small scrapers with the tank of the bucket to 3m3.
When moving the earth masses for the distance over 120 meters, it is most advisable to use scrapers with a tank of 10m3 bucket and more.
In some cases, instead of scrapers, it is advisable to use excavators in a pair with transport units.
When calculating the volume of the developed soil, it should be aware that the developed (loose) soil increases in the amount. The difference varies within 30% against the volume in a tight state.
Acceptance of completed earthworks is made by the general contractor's geodetic service from the Contractor. In the necessary cases (stipulated by the project) the Contractor presents the results of the primer seal analyzes. The vertical layout of the construction site is an important preparatory stage for the construction of an object.
Cutting vegetable soil is stored on the territory of the construction site or transport to the place of recycling.
Based on this condition, as well as the transportation range of the soil, one of the following works methods are chosen:
1. Cutting layer of the excavation and transportation machine, loading in motor vehicles excavation machine and transportation to the place of storage (use).
2. Cutting the layer and transportation of its earth-transport machine.
In the first case, as a rule, a bulldozer, auxiliary - excavator and automotive vehicle, are prescribed the main earthmoving machine. In the second, all operations are performed by scraper.
Selection of a set of mechanisms start with choosing a leading machine for the development of soil. Then, based on the performance, the duration of the cycle and the main parameters of the leading machine, the auxiliary machines for loosening, transportation, spacing, seals, and other types of work are selected.
Considering that the same work can be done by various sets of machines, and the same kit can work on various technological schemes, with a preliminary choice of sets are guided by the established practices.
Large machines with a lot of productivity are economically beneficial to use at work with significant volumes, and with small amounts of work it is cheaper to apply small cars.
The development of soil bulldozers are performed mainly in two ways: trench and layer .
Fig. 2. The soil development scheme by bulldozer:
but -trench; b. - layers; 1 , 2 , 3, - cutting sequence Trench development method is used to reduce losses when moving the soil at a distance of up to 50 m. Parallel strips - trenches depth from 0.4 to 0.6 m - are obtained by several passes of the bulldozer one by the same place. Trench width is taken equal to the length of the dust of the bulldozer, and the jumpers left between the trenches, 0.4 m wide in connected soils and 0.6 m - in unnecessary. The jumpers are developed after the passage of each trench.
Fig. 3. Trench Method of Soil Development When Sminding: 1 - trenches of the bells of the bulldozer; 2 - intermediate rollers; 3 - jumper by trenches; 4 - Mound.
Transmitting the carriage over 50 m every 25 m is arranged intermediate shafts, which are then moved by two or three paired bulldozers.
The device method of intermediate rollers is as follows. On the path of transportation of the soil every 40 ... 50 m, the location of the intermediate rollers of the soil is planned. The bulldozer develops and moves the soil with separate invigays. First, the soil moves into the first roller, then in the second, third and further beyond the limits of the excavation. At the same time, the amount of idle strokes of the bulldozer increases, but at each workshop, the bulldozer moves the maximum amount of soil. With a trench method of developing a soil of loss, it is significantly reduced due to a decrease in winding from a bulldozer dump in the process of transporting the soil to the place of its sup.
With a layer-by-layer method, the excavation is developed by layers on the thickness of the filtered chips in one passage of the bulldozer consistently across the entire width of the excavation or separate parts. This method is applied with a small cutting depth and complex outlines.
With the layer-by-layer scheme, the development of the soil is made by parallel stripes, and each previous strip is overlapped by subsequent from 0.3 to 0.5 m.
Fig.4. Calculation scheme of the cutting of the vegetable layer. L cf. - average distance of moving vegetable soil during embankment, h. - the height of the dump of the soil, BUT - a strip of clearing vegetable soil, IN - Width of the dump of vegetable soil at the bottom, b. - Width of the dust of vegetable soil at the top.
On the clearing lane BUT (length of up to 150 m) by the movements of the bulldozer from the edges to the center formed by the vegetable soil of width ; Square
where b. Accepted within 1.5 ... 1.9 R., and R. - Radius of cutting at the level of caterpillars for the excavator used during loading (selected by).
Dump height h. Accepted from 2 to 4 m. The average distance of the movement of the soil L cf. = BUT/ 4, m.
The Bulldozer based on the tractor T, T-100, T-130, and T-180 in the width of the trench, respectively, 20-40 m, 40-60 m, 60-100 m, the main characteristics of the bulldozer, the brand of the bulldozer, the main characteristics of the bulldozer are Dump, dump height, dump type, control, power.
An excavator is selected to develop a cut-into soil with loading in the vehicle. The most preferred excavator is a direct shovel. With the volume of work more than 10 thousand m 3 3, it is recommended to use machines with a bucket capacity of 0.5 m 3 or more. The main characteristics are the excavator brand, the bucket capacity, the boom length, the greatest radius of the digging, the greatest unloading radius, the greatest discharge height, power.
Operational performance of the bulldozer P EB:
(17)
V P.- the volume of the prism of drawing, m 3,
where At 0. and N.- The length and height of the bulldozer dust, m; To R. - coefficient of soil breaking, software; φ 0 is the angle of natural sloping of the loose soil; To u - the coefficient of accounting the area (Appendix 2); To S. - the coefficient of preserving the soil on the knife during transportation, To S.=1-0,005L cf.; To B. - the coefficient of using a bulldozer into a shift of software; T. - a unit of time for which the performance of the bulldozer is determined, 8 hours; T C. - time of the working cycle, sec;
T C \u003d T P + T P + T XX + T M, (19)
where t P. - the cutting time of the soil,
t P. - Duration of movement:
t xx - Duration of idle:
t M. - maneuvering time.
Cutting speeds, soil and transport movement are shown in Appendix 2.
The amount of machine-shift required to perform work is determined by the formula
V gr - The volume of the soil developed, m 3.
The number of bulldozers and the replacement of their work are determined during the preparation of the work schedule, based on the segment of the time allotted to perform this type of work (initial data).
Excavator operational performance
, m 3 / cm (25)
where q.- bucket capacity (m 3); To N. - the filling coefficient of the bucket (Appendix 3); t CPU- cycle time when loading a vehicle (min) software (Appendix 3); To R. - the coefficient of tearing the soil of the software; T. - a unit of time for which the performance is determined (8 hours); To them - The coefficient of use of machines in shift, by depending on the soil group.
Regulatory Excavator Performance:
where N BP - time rate, person-hour per 100 m 3 soil by.
Further, the calculation uses the smallest performance.
The required amount of excavator machine-shift is determined by formula (24).
Calculation of the required amount of transportation for excavator
The calculation is starting from choosing a type of vehicles by Appendix 5. The following factors affect the choice of brand and number of automobiles: automotive lifting capacity and excavator production. With an increase in the carrying capacity of the automobile, the simple excavator decreases and its development increases. But the more powerful automotive, the more expensive the cost of the set of cars. ROOM RASTING OF THE BUCH q.(m 3) to automotive lifting capacity Q., T, 1:10, i.e. For an excavator with a bucket capacity q.\u003d 0.65 (m 3) expedient to use the automotive industry Q.\u003d 7 t, etc. (Appendix 3.5). Specifications such as carrying capacity, body capacity, rotation radius, height to body top, maneuvering time during loading, maneuvering time when unloading, speed in a loadable state, verge rate.
When choosing motor vehicles, the following conditions should be observed:
The height of the side must be at least 100 mm below the loading height of the excavator;
It is necessary to strive for one car to be immersed from 4 to 7 soil buckets, because With a small amount of soil in the body of the dump truck when driving, unwanted dynamic loads occur, and with a large number of buckets increases the loading time.
Number of buckets n K. Calculated by the formula
, (27)
where V Kuz.Sam - automotive load capacity, t; To N. - filling coefficient of the bucket; - Capacity of the bucket of an excavator, m 3; To R. - The coefficient of bursting of the soil.
The number of buckets is rounded up to an integer both in large and at a smaller side, taking into account possible overload or underloading of transport within 10%, while the ground is ground in the body, T:
γ cp -average density in natural occurrence, t / m 3, software.
According to the formula (27), the number of buckets required to fill the transport is determined based on the carrying capacity without taking into account the body capacity, so it is necessary to check the soil capacity in the body
(32)
During the transport of light soils, the geometric capacity of the bodies of automotive vehicles may not provide loading capacity. In such cases, it is recommended to extend boarding by temporary shields.
Work cycle time:
T C \u003d T P + T PR + T P + T M + T AP, (29)
where t P. - parking time under loading, min ,; - duration of the excavation cycle of the single-circuit excavator (Appendix 3); t AP.GR - time cycle of the excavator; t AP.GR - time of the mileage of the dump truck to the place of unloading, taking into account delays in the way, min; L. - Distance to the place of dump (km); To P. - coefficient of increasing run time due to a slowdown during braking and overclocking software (Appendix 5); t R. - discharge time, min (2-4 min); t M. - time maneuvering, min (5-15 min); t AP.P. - run time by empty, min.
- automotive velocities by empty and in a loadable condition, respectively.
Based on the above, we select the number of vehicles :
Vertical platform layout
The technological process on the vertical layout of the site consists of the following operations: pre-jamming of the soil (if necessary); its cut; Transportation to the place of laying, leveling (if necessary) and seal.
For the main landing and transport machine, it is recommended to take a bulldozer or scrapper. The excavator for this type of work in industrial civil construction is extremely rare.
The movement of the soil from the excavation into the bulldozer is recommended to produce with a distance of up to 50 m - along the usual scheme; 50- 100 m - with the accumulation of soil in intermediate shafts; More than 100 m - the use of the bulldozer is inappropriate.
Building an earthwork card
Cartogram of earthworks is a graphic image of the work performed. It indicates: a breakdown of a plot to squares; workers, red and black marks; scope of work on the squares; The position of the zero line of work (LPR) and the slopes of the construction site.
The average distance of the movement of the earth masses determines the choice of the type of earthmoving machines, the area of \u200b\u200befficient use of which is installed at a rational distance transportation of the soil. In addition, this parameter is necessary when the norms of time and rates are found. When comparing several embodiments of planning work, the range is calculated with an accuracy of 1 m.
There are several ways to find the average transportation distance of the soil. At the same time, two approaches are being implemented in practice. If the scope of work is small and the platform has one unlocked zero line, then the average distance of the movement of the soil is determined in general for the entire platform. In some cases, the square grid can intersect several zero lines or have one closed line. Then the site is divided into several sections, while observing the zero balance of the volume volumes and the embankment on each site, several distances of the movement of the soil are calculated and there is a weighted average distance.
In the course project in the presence of a statement of the chess balance of earth masses, the average carriage range of the soil L CP. can be determined by the formula
where v I. - Private notch, moved from i.-gone square, m3; L I. - The distance that this volume is transported, m.
Since the plan for the distribution of earth masses according to the method of a chess balance is not optimal, then the calculated value L CP. will have errors.
Also, the average distance of the soil movement can also be determined as a distance between the centers of gravity of the excavation and the embankment by the method of statistical moments. Calculate the moments of volumes relative to any coordinate axes:
Here V B.,V N. - soil volumes within the simplest figures, m 3;
X in, x n, y in, y n- Coordinates of the centers of gravity of the simplest figures , m 3.
Development of the soil movement scheme
With an indicative method of determining the average distance of the movement of the soil when planning a platform planned work and machine-containers are significantly lower than the actual. In addition, the movement of the soil in the production of work is rather impossible, which in turn increases the gap between the planned and actual values \u200b\u200bof costs.
For a normal organization of work, it is necessary to build a soil movement scheme.
When using a bulldozer for vertical platform layout, a calculation should be calculated by formulas (17) ... (24).
When developing the scheme of movement of scrapers, it should also be remembered that their performance affects the direction of the slope of the site, as well as what the soil cut and fill the bucket only with the straight-line movement of the staple.
Clearing the territory of the construction site is a set of events, including the production of works on the cutting of trees and shrubs, a crowd of stumps and cleaning stumps, preserving the fertile soil layer, demolition of buildings, engineering networks and communications, swelling of holes, pitchers and trenches, cleaning and planning of the territory and other types of work.
Clearing the territory and cutting of vegetable soil is carried out in accordance with the project of the work of work, which indicates: the thickness of the cut layer of vegetable soil, the site of cutting, collection and obmissions of plant soil; Ways to protect against damage or transplantation used in further trees and plants; sections of the storage of vegetable soil cut from the construction site suitable for use in improvement and landscaping; Methods and procedure for reclamation of soils.
The boundaries of the sections to be cleaned must be fixed by well visible milestones, pointers, referees.
Foresting or transplanting forests and shrubs in the construction site is made only when agreed with local self-government bodies and government agencies and receiving a carbon ticket strictly within the boundaries established by the project. Green plants that are not subject to cutting should be marked by pointers or fenced and transferred to the safety of a construction organization on the act with an application of their location schemes on the ground.
Clearing the territory from trees can be performed with a cutting of trees in place and the subsequent export of logs or cutting of the fallen trees outside the construction site.
Cleaning residue roots from the vegetable layer is made immediately after cleaning the territory from the stump and logs. The seized roots and bushes are removed from the clearing area into specially reserved places for the subsequent export.
The vegetable ground to be removed from the built-in area should be cut off, move into specially selected places in the construction site or beyond and fit into the dumps for further use during the reclamation of impaired land or other needs in accordance with the project.
Prior to the production of work on the cutting of the soil of the vegetable layer, work should be performed:
- Axis has been made and designated the boundaries of the site (routes) of the work of work;
- The places of dumps of dumps of vegetable soil are indicated;
- Produced a working breakdown of the site with the fixing of the split signs;
- Familiar with the technology and organization of work and are trained in safe working methods workers and engineering workers.
When working with vegetable ground, it should not be mixed with the underlying unimpressive soil, as well as to contaminate it with waste, construction trash.
Reclamation of broken lands is a complex of engineering activities for the technical training of land for subsequent target use and the biological development of land for restoring their fertility.
Recultivations are subject to all disturbed by the construction of land, in which there were changes expressed in violation of soil cover, in the formation of new form of relief, changing the hydrogeological regime of the territory (drainage, flooding), as well as adjacent areas, in which the construction of productivity has occurred as a result of construction.
Recultivation is carried out in two stages - technical and biological.
The technical stage provides for the implementation of land preparation activities exempted after the development of the field, to subsequent targeted use in the national economy. These include: rude and finishing layout of the surface of impaired land; Drilling and (or) terraceing of dusts of dumps and sides of career recesses; Preparation of sections (cutting down, shrubs, cleaning of stones, etc.); selective removal, transportation, warehousing (if necessary) and applying potentially fertile breeds to reclative land and fertile soil layer; elimination of the consequences of precipitation of open-pit mining and anti-erosion events; Failure of the rock or filling with water residual career recesses; a complex of landliorative measures aimed at improving the chemical and physical properties of unscrewing soils, which are consistent with the surface layer of reclaimed land (if necessary); Construction of roads and hydraulic structures, etc.
The biological stage of the recultivation includes measures to restore the fertility of reclaimed lands. These include: landing of wood-shrub crops, sowing perennial herbs, carrying out agrotechnical events, phytomelic and other works aimed at restoring flora and fauna.
4. Preparation of the construction site. Cutting vegetable soil, territory layout.
After making the construction of the drainage ditch and the waterfront shaft from the soil taken out when the ditch is seized, proceed to the cutting of plant soil. The cutting of vegetable soil is performed by a bulldozer. At the same time, the bulldozer performs two operations to develop and move the soil. Vegetable primer is stored in a bourge, which can be placed on the scheme described above. In this case, we will get an additional water facilitation. All soils are classified for the difficulty group of their development of a particular earthmoving machine. The same type of soil for various machines can have different groups of difficulty developing. Moreover, depending on the humidity and density of the soil of one and also varieties, the presence of foreign inclusions of the Group of difficulties may vary for the same machine. For example, vegetable primer belongs to the primers of the first (I) group of difficulty developing a bulldozer if there are no roots of trees and shrubs. If there are roots of shrubs and trees in the plant soil, the difficulty of its development increases, and such soil is already referring to the second (ii) group of difficulty developing a bulldozer. The structure of the difficulty of the development of the development causes the resistance of this soil cutting. Therefore, the cutting of the soils of various groups of difficulties are produced according to various schemes. For example, if the plant ground has a small thickness and refers to the soils of the first group on the difficulty of developing a bulldozer, and the bulldozer has sufficient power, then the grounding of the soil is carried out on a full depth over the entire length of the site, within which the bulldozer dump occurs. Such a slab is called tape. The name of the schemes is derived from the shape of a cut of soil shavings. The tape circuit of the cutting is used in the development of the most difficult soils relating to the CivGroup. However, in this case, the bulldozer dumps off into the ground is not entirely altitude, but the length of the site, within which the dump is filled with soil, is significantly increased. This leads to a sharp decrease in the performance of the bulldozer. In the event that the power of the bulldozer lacks in order to prealt the ground resistance, producing its cutting to the full depth over the entire length of the site, dumping as the motion of the bulldozer moves forward. In this case, the chips of the sliced \u200b\u200bsoil has the form of a wedge, and the slab circuit is called a wedge. The wedge scheme of soil cutting is used in the development of the primer group for the difficulty of development. Analyzing the stated material, we must understand that the scheme of stagnation of the soil is caused by its group of difficulty developing and the capacity of the bulldozer. Moreover, in all cases, the bulldozer must be selected so that its power corresponds to the group difficulty of the soil. In this case, we exclude the influence of the power factor of the bulldozer on the soil cutting scheme. The difficulty of developing soils can be reduced by performing additional technological operations. For example, dry soils and soils having extraneous inclusions can be disappeared by the ripper immediately before developing the soil. The moistened soils in which the soil sticking to the knife and the cutting edge of the earthmoving machines occur, as well as the inconvenience of moving machines can be dried using the construction of surface and depth drainage systems. In this case, it is necessary to keep in mind that any our decision must be justified. For example, if the technical and economic indicators are raised when performing operations aimed at reducing the difficulty of developing soils, these additional works are justified from the standpoint of the economy and labor intensity. Otherwise, additional operations are not appropriate.
Figure 5 shows the schemes of cutting of vegetable soil by a bulldozer.
Figure 5 - Schemes forces of vegetable soil I and II group
difficulty bulldozer: a) tape; b) - Wedge.
The surface of the site in the construction zone is planned by a bulldozer with giving the slopes that ensure the flow of water from the pipe.