Generación de Nuevo Conocimiento: Artículos publicados en revistas especializadas - Electrónicos
Dynamic behavior of naturally desiccated clays via resonant column testing at constant water content conditions
Fecha
2018-06-20Autor
Pineda, Jorge A.
Cruz, José A.
Ávila, Pamela Y.
Institución
Resumen
The surficial soil at a western region of Bogota (Colombia) is a sedimentary deposit of high
compressibility lacustrine clays with lens of sand and peat and overconsolidation ratios (OCR)
from 1 to 9 due to desiccation processes. This geomaterial is subjected to matric suctions up to
800 kPa that generate cracks above the groundwater level, in the vadose zone. Small-strain
dynamic properties such as shear modulus, material damping, and shear wave velocity are key
parameters for an adequate analysis and design of geotechnical structures like shallow
foundations or pavements in this particularly condition. In order to characterize the dynamic
behavior and its relationship with initial state and confinement level, fixed free resonant column
tests at constant water content were performed in specimens of those desiccated, stiff, and
overconsolidated materials. It was found that the influence of suction and confinement stress in
shear modulus and damping ratio is more pronounced in lightly overconsolidated materials for
similar water contents before the air entry value (AEV). Nonetheless, after the AEV, the stiffness
response and the shear wave velocity take similar values in an independent way of the initial
state. In highly overconsolidated conditions, the overall dynamic response is fairly similar before
and after the AEV, despite the stress history.