Accumulated strain and dynamic strength of dredged soil solidified with soda residue

摘要

The dredged soil was solidified with soda residue (SR), ground granulated blast furnace slag and carbide slag. Dynamictriaxial tests were conducted on solidified soil under different confining pressure, SR content and curing age. The accumulatedstrain (?_p), critical dynamic stress (σ_(dcr)), dynamic strength and empirical formula were studied. The results revealedthat increasing confining pressure, SR content and curing age reduced ?_p and increased σ_(dcr) and dynamic strength of solidifiedsoil. The relationship between ?_p and loading cycles (N) of solidified soil conformed to an empirical model, and thefitting parameters A, B and C were obtained. The state of the ?_p vs. N curve could be judged according to A, B and C, andthe discriminating standard was given. Based on the A × B fitting formula, a method for calculating σ_(dcr) was proposed. Thevalues of σ_(dcr) for solidified soil were 93.56 kPa to 231.30 kPa, which were greater than clay subgrade filler and similar tosolidified soil subgrade filler. The values of σ_(dcr) were greater than the dynamic stress level of the subgrade bed, indicatingthat solidified soil met the dynamic stability requirement. The dynamic cohesion (c_d) and dynamic internal friction angle (φ_d)of solidified soil both decreased with the increase of the failure loading cycle. The c_d varied greatly, ranging from 58.4 kPato 85.35 kPa, and φ_d was about 11.96° to 13.05°. The solidified dredged soil can be used as filler in subgrade engineeringfrom the viewpoint of accumulated strain and dynamic strength.