Geotechnical Engineering Journal of the SEAGS & AGSSEA ISSN 0046-5828
Vol. 55 No. 3 September 2024
The Failure of Road Embankment Along the Canal during Driven Piles Construction in Thickness of Soft Sensitive Clay
Salisa Chaiyaput, Taweephong Suksawat, Jakkaphong Wongkumchun, Jiratchaya Ayawanna, and Thanadol Kongsomboon
ABSTRACT: The pile-retaining wall at Nonthaburi rural road no. 5036 was constructed using reinforced concrete piles or driven piles combined with a concrete retaining wall. The purpose of this structure was to enhance the slope stability of the canal-side road (road embankment along the canal). The damage to the driven piles occurred during the pile construction at 18 m depth below the ground surface. The resistivity survey and screw driving sounding test were employed to investigate the thickness of soft clay layers and unexpected stiff soil layers at the failure area. The field vane shear test was employed to investigate the sensitivity of the soft clay layer. Furthermore, the finite element model was analyzed to verify the failure behaviour of the road embankment during the driven pile’s construction. Consequently, the investigation revealed that the subsoil in the failure area exhibited sensitivity values. The subsoil consisted of a layer of soft clay to medium stiff clay, ranging from 2-10 m below the ground surface, while the subsoil consisted of stiff clay below a depth of 10 m. The installation of the 18-m driven pile caused a disturbance in the soft sensitive clay layer above the stiff soil layer, resulting in a reduction in the strength of the soft clay and affecting the displacement of the driven pile during construction. Furthermore, the occurrence of rapid drawdown causes water seepage to continue to flow toward the canal side. This phenomenon produces active forces on the slope of the road embankment along the canal. As a result, the road embankment along the canal side can collapse due to a disturbance in the sensitive clay layer with rapid drawdown. The result was agreed with the study findings obtained by the finite element model.
KEYWORDS: Clay Thickness, Driven Pile, Sensitive Clay, Soft Clay, and Pile Damage.
