TY - JOUR
T1 - Development of a mechanistic-empirical model to predict equilibrium suction for subgrade soil
AU - Saha, Sajib
AU - Hariharan, Narain
AU - Gu, Fan
AU - Luo, Xue
AU - Little, Dallas N.
AU - Lytton, Robert L.
PY - 2019/8/1
Y1 - 2019/8/1
N2 - Suction in subgrade layer reaches an equilibrium condition several years after construction of the pavement. The equilibrium suction has a direct influence on the resilient modulus of subgrade soil. In the current mechanistic-empirical pavement design guide, equilibrium suction is determined based on the empirical relationship with water table depth. However studies have shown that other critical factors also influence equilibrium suction. In this study, a new mechanistic-empirical model is presented to predict equilibrium suction considering the effects of physical properties of the soil and climatic factors. A simple regression model is also generated to predict the equilibrium suction from readily available parameters i.e., Thornthwaite moisture index (TMI), plasticity index (PI), and dry suction value at surface (udry). In the final section of this paper, the effects of TMI and vegetation on equilibrium suction are evaluated for various soil classes and TMI ranges, respectively. A contour map of the equilibrium suction values for the entire continental United States has been generated using the geographic information system (GIS) platform and followed by the model predictions.
AB - Suction in subgrade layer reaches an equilibrium condition several years after construction of the pavement. The equilibrium suction has a direct influence on the resilient modulus of subgrade soil. In the current mechanistic-empirical pavement design guide, equilibrium suction is determined based on the empirical relationship with water table depth. However studies have shown that other critical factors also influence equilibrium suction. In this study, a new mechanistic-empirical model is presented to predict equilibrium suction considering the effects of physical properties of the soil and climatic factors. A simple regression model is also generated to predict the equilibrium suction from readily available parameters i.e., Thornthwaite moisture index (TMI), plasticity index (PI), and dry suction value at surface (udry). In the final section of this paper, the effects of TMI and vegetation on equilibrium suction are evaluated for various soil classes and TMI ranges, respectively. A contour map of the equilibrium suction values for the entire continental United States has been generated using the geographic information system (GIS) platform and followed by the model predictions.
KW - Equilibrium suction
KW - Geographic information system
KW - Moisture active zone
KW - Subgrade soil
KW - Thornthwaite moisture index
UR - http://www.scopus.com/inward/record.url?scp=85066104149&partnerID=8YFLogxK
UR - https://www.sciencedirect.com/science/article/pii/S0022169419304809?via%3Dihub
U2 - 10.1016/j.jhydrol.2019.05.035
DO - 10.1016/j.jhydrol.2019.05.035
M3 - Article
AN - SCOPUS:85066104149
SN - 0022-1694
VL - 575
SP - 221
EP - 233
JO - Journal of Hydrology
JF - Journal of Hydrology
ER -