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Examples of Processing Results:

Hidden Defects in Concrete

Pipe Detection

Pile Foundation Grillage

Engineering Geology

Railroads

Building Control

Municipal Engineering

Non-destructive Testing

Air Voids in the Soil

Illegal Tie-in Into Oil Pipeline

Archeology

Relief Map

3D Processing

Certificate:

Certificate of state registration program GEORADAR-EXPERT

Publications:

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GPR SURVEY OF RAILWAY

(A fragment of a technical report)

...Geophysical survey was carried out in August 2011 by geo-radars OKO-2 with an antenna block 250 MHz, LOZA-B. The survey of the canvas by georadars with the use of the regular software did not allow to isolate geological layers over the entire depth of time scan (OKO - 400 ns, 500 ns), Fig. 4.13.

No methods of filtering and processing radarograms in the regular programs (GeoScan32, Krot) have made it possible to increase the information content of the geophysical sections. Only the sole of the ballast is confidently determined by the georadars (Figure 4.13), the thickness of the ballast on unstable path segments exceeds 2 m. The maximum radio visibility in the main area does not exceed 70 ns, so the base of the roadbed and the geological layers below the soles do not stand out. After passing through the ballast, the probe pulse of the georadar is rapidly damped in the clay soils of the body and the base of the embankment. At the same time, zones with low-frequency, multiple reflections, corresponding to the areas of watered soil of the body and the base of the embankment (Figure 4.13), are identified below the ballast on the radargrams of LOZA-B.

Comparison of the GPR profiles obtained using different ground penetrating radar.

Fig 4.13

In October 2011 the scientific station for the study of permafrost for experimental use was provided with the GEORADAR-EXPERT software. With the help of the GEORADAR-EXPERT, sections were made on the attribute of the real part of the complex relative permittivity Re (epsilon). The sections created by the GEORADAR-EXPERT software allowed:
  • Increase the information content of the geophysical section to a depth of 7-12 m (three times as compared with the regular programs);

  • "To see" the physical condition of the soil of the body and the base of the embankment, to identify the areas of watered soils;

Analysis of the sections Re (epsilon) in conjunction with the results of instrumental observations and drilling led to the following conclusions:
  • According to drilling data, the most common soil of the body and the base of the embankment is loam, according to Table 7.1 of the Guidelines [4], loams with a permittivity above 20 are water-saturated;
  • Water-filled layers are located at a depth of 3-7 m from the surface of the ballast prism, which corresponds to the lower part of the body of the embankment and the upper part of the base of the embankment. Consequently, in the warm period of the year, most of the water enters the body and the base of the canal from the drainage structures, as well as with atmospheric precipitation. The supply of groundwater from deeper horizons is not revealed, which is explained by the presence of a water stop from permafrost on the indigenous slope;
  • The width of the regions of water saturated soils is 20-50 m, this indicates that the water transit is carried out through limited sections, confined to buried streams and local relief depressions.
Groundwater flows "meander" and cross the road at various angles (Fig. 4.14). Debit groundwater flows reach significant values, so the PC (пк)№ +00 underground watercourse, timed to coincide with the base of the embankment, crosses well SKV, with such high speed that formed the turbulent swirl of the water table in the well and the characteristic sound of flowing water.

Fig.4.14

Where, according to instrumental observations, sediments of the roadbed have been identified, areas of moist and water-saturated soils in the body and base of the embankment have been found. The zones of water-saturated grounds attract attention in stable areas, the stability of the railroad track is explained by the fact that the body and base of the roadbed are composed of coarse clastic soils that do not lose their strength properties with increasing humidity. A comprehensive analysis of geophysical and geological data made it possible to draw the following conclusions:
  • Deformations of the roadbed are directly related to atmospheric precipitation, the regime of transit and discharge of groundwater;
  • The stability of the canvas is affected only by the shallow-depth groundwater of Quaternary sediments, signs of transit and unloading of formation-fractured waters in the basement of the earthen cloth are not detected;
  • he railway is deformed only on sections of the road, where in the base of the roadbed there is a loam on the ways of transit of groundwater from drainage structures and stagnant formations.
In the warm season, the deformations of the roadbed become more active with the precipitation of precipitation. This is due to increased debit of underground watercourses and rising water levels in stagnant formations. For this reason, the body and base of the railway embankment are saturated with water, and their strength decreases.

ГЕОРАДАР-ЭКСПЕРТ. Разрезы.

 

 

 

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