Due to the withdrawal of moisture, the ground beneath a building slides downward. As a result, the foundation sinks, compromising the structure's stability.
Shrinkage of soil occurs when moisture is extracted, causing the foundation to move downward. As a result of soil desiccation caused by trees or other vegetation, clay soil usually subsides.
A structure's subsidence can be diagnosed early by recognizing the signs and considering appropriate measures. Cracks in slabs without intersections, outward movement of exterior walls at the top, and cracks in slabs that grow in dry months but close in wet months are symptoms of subsidence.
- The superstructure typically experiences wider cracks in the dry season and smaller cracks in the wet season.
- Brick walls have cracks that run diagonally across their interiors and exteriors.
- Compared to their width at the bottom, they are wider at the top.
- Cracks are larger than 3 mm in width.
- It is visible near the windows and doors that there are cracks.
- Recent changes in the soil moisture beneath the foundation have resulted in a decrease in moisture content.
- Concrete slabs have single lines of cracks, which have no intersections.
- The topmost walls of a building move outward.
- There is a problem with the concrete driveway.
- Level distortions of the foundation increase with time and seasonally, especially in dry months, according to time change elevations.
- The bowl shaped foundation has a low point near its center, which rose around its perimeter several years ago.
- The exterior foundation grade beam does not have a gap between it & the adjacent soil at grade, especially during the dry season.
- More than 25 is the plasticity index of soil.
- When excavating, the soil beneath the grade beam is dry, more than 2.5 cm to 5 cm deep.
- The roots of a large tree extend toward the structure at grade.
