Methods to determine shearing resistance in the laboratory:

1. Direct shear test:
- This method involves applying a direct shear force to a soil specimen to determine its shearing resistance.
- The test measures the shear strength parameters of the soil, such as cohesion and internal friction angle.

2. Triaxial shear test:
- In this method, a cylindrical soil specimen is subjected to confining pressure while shearing forces are applied.
- The test helps in determining the shear strength of the soil under different stress conditions.

3. Vane shear test:
- The vane shear test is used to determine the in-situ shearing resistance of cohesive soils.
- A vane is inserted into the soil and rotated to measure the soil's resistance to shearing.

4. Unconfined compression test:
- In this test, a cylindrical soil sample is subjected to axial compression until failure occurs.
- The test helps in determining the unconfined shear strength of the soil.

5. Ring shear test:
- The ring shear test is used to determine the residual shear strength of a soil specimen.
- The test involves shearing a ring-shaped sample of soil under a constant normal load.

6. Box shear test:
- In this method, a soil specimen is placed in a box and subjected to shear forces along a predefined plane.
- The test helps in determining the shear strength properties of the soil.
These laboratory methods provide valuable information about the shearing resistance of soils, which is essential for various geotechnical engineering applications.