Expansive soil is a kind of special soil with soil particles mainly
composed of hydrophilic minerals, and has significant deformation
characteristics of water absorption expansion and water loss shrinkage.
This characteristic often brings great harm to engineering construction.
Relying on the foundation engineering of the bridge on the expansive
soil slope of the Jiangxi-Huaihe River, this paper studies the effects
of slope excavation and rainfall on the horizontal deformation of the
bridge foundation by using temperature simulation and humidity fields
and numerical simulation methods. The research results show that during
the excavation process, the bridge foundation will produce a horizontal
displacement pointing to the top of the slope, and the rainfall after
excavation will cause the horizontal displacement of the bridge
foundation to decrease and gradually develop in the opposite direction.
During the excavation process, the rebound of slope excavation is the
main factor affecting the horizontal displacement of the bridge
foundation. Under short-term rainfall conditions, the hygroscopic
expansion of the slope soil becomes the main influencing factor. Under
extreme rainfall conditions, the main cause of the horizontal
deformation of the bridge foundation is The influencing factors are
transformed into the reduction of the soil weight of the slope and the
strength of the soil material.