During underground infrastructure construction, surrounding buildings may or may not get impacted during the process of tunnelling work. If a building gets impacted, it is due to soil settlement and the design displacements. Impacts could be in the form of flexure, torsion, and shear that exceeds the ultimate bearing capacity of the structural member. Different types of scenarios might occur and it needs to be addressed correctly.
Given below are such circumstances wherein failure can occur and appropriate measures to overcome them.
Beam failure at buildings
For beam failure in the building, it is better to be strengthened as per pattern of failure. There are mainly two types of failure that occur in beams, flexural and shear failure. To overcome this type of flexural failure, main steel is provided at the bottom/top of the beam. Flexural failure occurs at the mid-span of the beam. Shear failure occurs at the end of the beam where the beam connects to the column. To avoid this type of failure stirrups are provided. So, strengthening of beams can be done by adding some temporary supports that can be easily transported and can be removed after completing the permanent support system.
Column failure at buildings
When columns are axially loaded, the reinforcement steel and concrete experience compression and buckling. When the loads are higher than the design loads, the bearing capacity of columns reduces and thus experiences higher compression which in-turn results in the buckling failure. The concrete column is crushed and the collapse of the column is due to material failure. To address this concrete column should have a sufficient cross-sectional area so that the stress is under the specified limit.
Water leakage at the Basement
Water seepage is one of the most common problems associated with basements during underground excavation works. It can lead to an abundance of problems that can ultimately harm your foundation, and due to excessive concentration of water on the substructure the concrete present in the retaining wall will experience spalling of concrete.
Conclusion
These are just a few circumstances; there can be many other impacts as well. If any infrastructure project is taking place near your house, it is always better to get expert structural engineers’ analysis to be on the safer side.There is also a need for proper ground engineering analysis to get insights on soil stabilization, slope stability, and bearing capacity of foundations.
Authored By : Narayanan
Email: sathiyans2021@gmail.co