Briefly about leveling
Excess is the difference between the heights of the points. To find the excess we can as the difference between the marks on the rails. If the count is greater then the lower mark. For example, the reading on the first rail will call “A” and the reference in the second “B”.
so, the excess we find as the difference between the reference h=a-B(h=1000-980=20mm.), when calculating the excess is very important to pay attention to the sign. If, however, the definition of excess all mark the same points are at the same height) this means that the surface is smooth. The frequency of leveling of crane tracks is 1 every 12 months and is determined Rules of construction and safe operation cranes NPAOP 0.00-1.01-07 (page 119).
finding the height of a point
visualize the context of the Baltic sea level, put a rail on point And in this point of known elevation ) then put the rail B in the place where you want to know the altitude. Report on Reiki starts from the heel Reiki to the sighting line. If we know the height of the point And we will easily be able to find out the height or elevation of the second point “B”, so for the first point accept that which is already known or the so-called rear point and the second point is called the front. As a starting point typically use special geodetic mark, which is called a rapper. The marker can be located in the ground is called groundwater rapper or wall - wall frame, can also be temporary or permanent.
At the construction site use of time frames. It can be both wall and ground, and pin, mortgage details and risks. It must be remembered that the point of the whole construction period should be the same.
for example, we need to find the point of the hatch, for this we need to install the rail on the frame, and remove the report from the point “A” then take the report to point B. Knowing the point a, that is, a reference point, we calculated the elevation of the second point B using the height difference. In some cases, the initial point we can take any arbitrary, for example, when leveling the surface and the lowest point will have a very large report.
Under the current legislation on industrial sites should be conducted annually surveys of gantry rails, rail. Part of the test is included as an external examination, and a comprehensive geodetic surveying which includes:
- geodetic checking parallelism rail
- deviation from the axis of each rail
- leveling - determination of the excess between adjacent rails
- definition of excess of one rail every 6 meters
- measuring actual dimensions between the rails along the axes
All measurement results are stored in a special table with a SNiP with permissible and actual variances for a specific object. Also indicate problem areas.
to the tables attached Executive geodetic scheme in format pdf. Here is an example of completed studies crane tracks
part of the integrated check valve includes:
- determination of the deflection of the beams
- parallel beams
- the actual dimensions between wheels of the crane
- the actual dimensions between wheels truck
- survey of the main diagonals of the crane(at the wheels, control points)
- distance between rails on a truck
We are also happy to perform leveling of floors, roads, livevox, sewer, formwork etc.
the hallmark of any object with a large area are smooth floors, shiny and smooth. But, the eye will not determine their correctness and compliance with the project. Leveling of the sexes is a fill mixture, which samovyrivnyuyucha, over a black floor screed. It is used to create a perfectly smooth base before you lay linoleum, carpet or lay parquet Board. Finishing the floors are poured concrete base. If for concrete tolerance is 20 mm in height to finished floor after leveling device-mass tolerances are 2 mm by 2 meters. We divide the building conventional grid squares 2m x 2m and stamped the actual level of the tops of the squares, the result is obvious. Here is an example of such shooting.