Differential settlement in foundation:
Usually, due to poor compaction, lower bearing capacity of the soil, high depth of hard strata, various changes in water content in soil are the basic reason behind the differential settlement of soil.
Apart from that, trees & vegetation is not good for foundation safety.
Soil consolidation is the main reason for differential settlement of the foundation.
Foundation push piers & foundation underpinning also harms the foundation, which leads to a differential settlement.