BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY:CESS Seminar: Soil sorptive potential: unitary definition of matri
 c potential
DTSTART:20191108T121500
DTEND:20191108T130000
DTSTAMP:20260925T072007Z
UID:7b37cfc4f0d398dbf0cab20da8d869ec073182d05e21d8dd72d39fcc
CATEGORIES:Conferences - Seminars
DESCRIPTION:Professor Ning Lu\, Colorado School of Mines\, Colorado\, USA
 \nAbstract:\nDespite the widely accepted notion that matric suction is the
  most fundamental variable for describing soil–water interactions in soi
 l under unsaturated conditions\, it is unable to describe several basic so
 il properties and behaviors such as pore-water pressure\, soil water densi
 ty\, and phase changes of soil water. A variable with greater explanatory 
 power\, sorptive potential\, is conceptualized as the origin of matric suc
 tion  or matric potential and pore-water pressure. The soil sorptive pot
 ential is the sum of the locally varying electromagnetic potentials compri
 sing van der Waals attraction\, electrical double-layer repulsion\, and su
 rface and cation hydration. Local thermodynamic energy equilibrium dictate
 s that the sorptive potential is always transformed or equal to matric pot
 ential minus the pressure potential within a representative elementary vol
 ume of matric potential. Limited verification was demonstrated by reducing
  the sorptive potential to the two well-established concepts of disjoining
  pressure and osmotic swelling pressure. Soil sorptive potential can be ex
 perimentally determined by the soil water retention curve. A parametric st
 udy was conducted to illustrate how soil and pore-fluid properties affect 
 sorptive and pressure potentials\, indicating that the pore-water pressure
  under unsaturated conditions can be as high as 0.6 GPa. Such locally high
  pore-water pressure is induced by the sorptive potential and provides an 
 explanation for phenomena such as abnormally high soil water density\, sup
 ercooling\, and decreased cavitation observed in fine-grained soils.\n \n
 Bio: \nNing Lu is professor of civil and environmental engineering at Col
 orado School of Mines (CSM) and the director of the joint CSM/US Geologica
 l Survey Geotechnical Research Laboratory in Golden\, CO. He is a recipien
 t of the ASCE 2007 Norman Medal\, of the ASCE 2010 Croes Medal\, of the AS
 CE 2017 Ralph B. Peck Award\, and of the ASCE 2017 Maurice Biot Medal\, as
  well as a fellow of ASCE\, Engineering Mechanics Institute\, and Geologic
 al Society of America. His primary research interests are flow and stress 
 laws in multiphase porous media\, rainfall-induced instability of natural 
 and engineered slopes\, geologic hazards\, energy storage in porous media\
 , and subsurface nuclear waste isolation. He is the senior author of the w
 idely used textbook Unsaturated Soil Mechanics (John Wiley and Sons\, 2004
 ) and the textbook Hillslope Hydrology and Stability (Cambridge University
  Press\, 2013).
LOCATION:GC B3 31 https://plan.epfl.ch/?room==GC%20B3%2031
STATUS:CONFIRMED
END:VEVENT
END:VCALENDAR