Assessment of the impact of construction on the change in the stress-strain state of the surrounding soil massif is a geotechnical forecast. Including assessment of the foundations of buildings and structures of the surrounding buildings.
The geotechnical forecast must be carried out for the structures of the surrounding development located within the previously assigned zone of influence of the structure under construction or reconstruction, which is determined depending on the depth of the excavation and the type of soil stabilization in accordance with:
- Federal Law “Technical Regulations on the Safety of Buildings and Structures” No. 384-FZ of December 30, 2009;
- SP 248.1325800.2016 “Underground structures. Design Rules”;
- SP 249.1325800.2016 “Underground communications. Design and construction in a closed and open way”;
- SP 22.13330.2016 “Foundations of buildings and structures”;
Geotechnical forecast and technical survey
Before performing a geotechnical forecast, it is necessary to conduct a technical examination of the state of the structures of the surrounding buildings located in the previously assigned zone of influence of new construction or reconstruction. Based on the results of the technical survey, the category of the technical condition of the surrounding buildings should be determined.
Evaluation of the impact from construction is carried out by mathematical modeling of changes in the stress-strain state of the soil mass using the finite element method using PLAXIS 2D programs . In the process of two-dimensional calculations, stresses, deformations, strength and stability in complex geotechnical systems are determined, taking into account the joint work of engineering structures and their interaction with the soil at the stages of construction, operation and reconstruction.
Inspection of the technical condition and geotechnical calculations
Services for the inspection of the technical condition of building structures of buildings and structures, as well as geotechnical calculations of the degree of influence of construction:
- Assessment of the impact of construction geotechnical forecast as a result of geotechnical calculations
- Determination of the value of additional deformations of the bases and foundations of the structures of the surrounding buildings
- Determining the radius of the zone of influence
- Analysis of initial data: geological structure of the site, design solutions for existing and under construction buildings and structures
- Schematization of initial data for building a mathematical model
- Verification of the calculation model
- Perform construction impact calculations
- Graphical interpretation and analysis of calculation results
- Formation of a technical opinion Assessment of the impact of construction
Geotechnical forecast application
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Forecast of horizontal movements of the sheet piling of the excavation Calculation of the impact of new construction on the surrounding buildings.
- Deformations of the soil mass during excavation
- Calculation of the impact of new construction on the surrounding buildings.
- Normal stresses during excavation
- Calculation of horizontal movements of the sheet piling of the excavation.
- Deformed FE Mesh
- Calculation of slope stability in new construction.
- Determination of the stability factor
Inspection of the technical condition of buildings located in the zone of influence of construction
When conducting surveys of buildings and structures of the surrounding area, a conclusion is issued on the technical condition of building structures and the values of permissible additional deformations in accordance with SP 22.13330.2016.
- Technical inspection of the supporting structures of the building, including measurement and survey and engineering and design work with photographic fixation;
- Compilation of a defective statement. Graphic applications (facades of a building project , location of defects on structures, photographs of fragments of building structures);
- Determination of the strength characteristics of materials of structural elements by the method of elastic rebound (Schmidt hammer) and/or ultrasonic device;
- Determination of the general category of the current state of building structures of the building;
- Formation of the technical conclusion “Survey of the technical condition of building structures”.
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Development of a geotechnical monitoring volume
Deformation monitoring of buildings and structures located in the zone of influence of construction should show to what extent the design parameters and calculation justifications coincide with the real parameters, as well as enable construction and operating organizations to take the necessary measures in a timely manner to prevent possible deformations or eliminate the consequences of such deformations in the course of work on the construction of the pit and the construction of the designed building.
Development of design or working documentation for constructive solutions for excavation fencing in the form of a sheet pile or “wall in the ground”
For the erection of buildings in conditions of dense urban development, when constructing zero-cycle structures, depending on the engineering and geological conditions of the construction site, the depth of the construction pit, the remoteness of the buildings of the surrounding buildings and many other factors, very often the pit has to be fixed in the form of sheet piling or ” walls in the ground.
Geotechnical forecast and its price
Construction impact assessment work cost and geotechnical forecast
| Type of design work | Link to the collection of prices for design work | Estimated cost of work, rub. |
| Inspection of the technical condition of the building structures of the building (structure) falling into the zone of influence of construction (with the construction volume of the building being inspected Vstr = 10,000 m3) | MRR-3.6-19 | 130 000 |
| Performance of work on driving a pit when examining the foundations of a building (structure) that falls into the zone of influence of construction (1 pit) | SBC at IGI and EEI, 1999 | 30,000 |
| Development of the volume “Assessment of the impact of construction” on the existing building (1 design section) | MRR-6.1-19 | 70 000 |
| Development of the volume “Geotechnical Monitoring Program” | MRR-3.2.67-13 | 100,000 |
The cost of the proposed design work on the preparation of a geotechnical forecast, taking into account the reduction factor, will be reduced by 30% relative to the estimated cost of performing these works, calculated according to the MRR and CBC only when ordering work through the application form
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