Abstract A transient water release and imbibitions (TWRI) method for measuring the soil retention curve (SWRC) hydraulic conductivity function (HCF) under drying wetting states is presented. The intellectual merit of TWRI its integration physical numerical experiments: it employs simple reliable measurement content by electronic balance to record signature unsaturated flow in sample, takes advantage robust inverse modeling capability simulate process. method; therefore, has two integrated...

Slope‐stability analyses are mostly conducted by identifying or assuming a potential failure surface and assessing the factor of safety (FS) that surface. This approach assigning single FS to potentially unstable slope provides little insight on where initiates ultimate geometry location landslide rupture We describe method quantify scalar field based concept Coulomb stress shift in state toward results from rainfall infiltration. The at each point within hillslope is called local (LFS)...

Abstract Modifications to a conventional laboratory testing system are described for direct shear of unsaturated soils at relatively low matric suction and net normal stress. Matric ranging from zero (saturated) about 10 kPa is controlled using hanging column assembly (ASTM D6836). Net stress 0.3 by directly applying dead loads the specimen via series aluminum top caps machined varying thicknesses. Precise control within these ranges makes apparatus ideal examining strength behavior sands,...

Abstract A constant-flow laboratory testing method (CFM) is presented for concurrently measuring the soil-water characteristic curve (SWCC) and hydraulic conductivity function (HCF) of unsaturated coarse-grained soils. Two computer-automated syringe pumps are employed to control volumetric water content a specimen periodically impose constant flow rates through specimen, respectively. Hydraulic (k) corresponding each increment determined from Darcy's law by steady-state gradient induced...

A series of experiments were performed to characterize the permeability, specific storage, capillary pressure, streaming potential coupling coefficient, and electrical conductivity a very low permeability Callovo‐Oxfordian clay rock at different water saturations. The formation is presently investigated as host store nuclear wastes because its (typically 10 nd saturation) high surface area. We first present constitutive transport equations including an electrokinetic cross‐coupling term in...

When heavy rainfall, such as that associated with tropical storms, falls on steep hillsides, shallow landslides are often one of the damaging consequences. To assess landslide potential from a strategy combined numerical simulation and field monitoring variably saturated hillslope conditions is developed. test method, hydrologic data paired sites in western North Carolina examined. The collected site where no has occurred used to identify calibrate hydromechanical parameters ground water...

Infiltration-induced landslides are among the most common natural disasters threatening modern civilization, but conventional methods for studying triggering mechanisms and predicting occurrence of these slides limited by incomplete consideration underlying physical processes lack precision inherent in limit-equilibrium analyses. To address this problem, spatial-temporal evolution failure is investigated a seasonally unstable section an interstate highway embankment, known as Straight Creek...

This paper extends Culmann's vertical-cut analysis to unsaturated soils. To test the extended theory, sand was compacted a uniform porosity and moisture content in laboratory apparatus. A sliding door that height of free face slope lowered until vertical cut failed. Digital images cross section upper surface were acquired concurrently. recently developed particle image velocimetry (PIV) tool used quantify soil displacement. The PIV showed strain localization at varying distances from prior...

Abstract Thermal conductivity of unsaturated soil depends on water content and type. A transient release imbibition method (TRIM) is modified to include measurement the thermal function (TCF) in conjunction with concurrent retention curve (SWRC) hydraulic (HCF). Two pairs dielectric needle sensors are embedded specimen monitor spatial temporal variation content, conductivity, diffusivity during drying wetting processes. Three different soils, including pure sand, silt, clayey sand used...

Infiltration-induced landslides are common in mountainous and hilly areas of the world. When they occur near transportation corridors, can impact public safety, impede transport goods people, damage infrastructure. This work presents a study hydrological behavior its effects on stability an active landslide located embankment along Interstate-70 west Eisenhower Tunnel central Colorado, USA. Groundwater dynamics were monitored for three years; two piezometers installed head slide one...

Abstract The soil water–retention curve (SWRC) is commonly theorized and measured in the positive matric suction or negative pore water pressure domain. However, all soils do not reach full saturation when decreases to zero. To date, few methods theories have been developed understand SWRC domain, which could play important roles field mechanical stability conditions, such as slopes under heavy rainfall levees rapidly rising table conditions. A method employing both transient release...

The authors, to their knowledge for the first time, produced two complete principal soil water retention curves (SWRCs) under both positive and negative matric suction regimes. An innovative testing technique combining transient release imbibition method (TRIM) constant flow (CFM) was used identify paths of SWRC in pore-water pressure regime unsaturated conditions. A 9.8 kPa is needed reach full saturation or close loop a silty soil. This work pushes understanding interaction into new...

To experimentally validate a recently developed theory for predicting the stability of cut slopes under unsaturated conditions, authors measured increasing strain localization in slope cuts prior to abrupt failure. Cut width and moisture content were controlled varied laboratory, sliding door that extended height free face was lowered until failed. A particle image velocimetry tool used quantify soil displacement x-y (horizontal) x-z (vertical) planes, calculated from displacement. Areas...

Snow-melt and rainfall induced landslides are major geologic hazards worldwide causing thousands of fatalities in several countries. Many failures occur along important highways, where it is particularly to keep the roads open working conditions. This paper presents an analysis active landslide on Interstate-70 west Eisenhower/Johnson Memorial Tunnels records indicate that hillslope has moved episodically during past 40 years with average over 0.6 m displacement two decades. A...

Infiltration-induced landslides are common geological hazards in the world. When they occur along highways threaten public safety and private property, block highway traffic, damage transportation infrastructure. Since hydrology of site affects effective stress distribution consequently stability slope, monitoring dynamic changes pore water due to climatic is important. This work presents study hydrological behavior an active landslide on embankment Interstate-70 west Eisenhower/Johnson...

An "artificial soil" created from industrial and municipal by-products is evaluated as an evapotranspirative (ET) cover via finite-difference based seepage modeling. Wetting front propagation simulated under a series of long-term (sustained) short-term (intense) precipitation events compared with actual infiltration data obtained instrumented test section over natural 24-day precipitation/evaporation sequence in Northeast Missouri. The predicted depth the wetting 250 cm, which compares...

A 2 ½ day National Science Foundation (NSF)-sponsored Workshop (Award No. CMMI-1248053) was held in July 2016 at the NSF headquarters Arlington, VA. The focused on fundamental principles that underlie current and anticipated developments geotechnical geoenvironmental engineering, with an emphasis how research community can contribute to real-world challenges facing humanity today. Forty researchers attended Workshop, representing a range of technical backgrounds, diversity, career stages....