PURPOSE OF SOIL INVESTIGATION
Providing the information of the foundation soil as: thickness of soil layers, their distribution in the scope of survey, the physical characteristics of each soil layer, characteristics of underground water, … to serving for design and construction work.
Soil investigation tasks include:
- Determining the distribution of rock and soil layers according to area and depth;
- Determining physical and mechanical properties of soil layers, underground water levels and preliminary assessment of water’s corrosion capacity;
- Evaluating load bearing capacity, subsidence compression of soil and rock layers;
- Evaluating unfavorable geological phenomenas that affect to the construction of deep excavation and proposing support solutions.
METHOD OF SOIL INVESTIGATION
- Geophysical method;
- Drilling combined with SPT test, taking soil samples for description and stratification. The volume of undisturbed samples for laboratory testing was taken in some representative boreholes: 1 sample to 2 samples for soil layer with thickness less than 5 m, 2 samples to 3 samples for soil layer from 5 m to 10 m, 3 to 4 samples for soil layers with thickness from 10 m to 15 m;
- Penetration test are performed alternately between boreholes, in order to determine the general transformation of the thickness of soil layers and their hardness;
- Vane shear test (for soil with state from soft to flowing);
- Laboratory test for undisturbed soil samples to determine soil classification criteria, durability and deformation of soils;
- Chemical analysis of some typical water samples.
APPLIED STANDARD
- TCVN 9363:2012 “Building surveys – Geotechnical investigation for high rise building”.
- TCVN 9437:2012 “The process of boring engineering geology investigations”.
