Evaluation of techniques for mitigating snowmelt infiltration-induced landsliding in a highway embankment

Infiltration-induced landslides threaten transportation infrastructure around the world, and impose both direct costs through repair remediation work indirect lost economic activity. Therefore, finding most cost-effective techniques to mitigate slope failures that can impact critical links is desirable. The Straight Creek landslide, which affects a segment of Interstate 70 in Summit County, Colorado (USA), has experienced seasonal failure driven by rapid springtime snowmelt infiltration since early 1970s, allowing changes its stability be studied. Past studies have established pore-water pressure increase caused hydraulic conductivity contrast between upper materials highway embankment. Two designs been applied site, including lightweight caissons beneath surface 2011 2012, horizontal drains near slide toe 2012. effects drains, as well an alternative drain design would extend into hillslope above embankment, are evaluated within rigorous hydro-mechanical simulation framework along with method generate field local factor safety. Model results show effect on safety no more than 1% during times instability, they do not affect hydrology cause destabilizing decreases effective stress surface. Horizontal intended reduce pressures, but location existing limit their efficacy due low subsurface underneath highway. indicate these only partially responsible for reduction movement rate installation, also lower annual cumulative levels Results could result increased periods intercepting downslope flow before it arrives at We conducted engineering geology case study perennial infiltration-induced landslide (USA). site 1970s. assessed two engineered implemented site: surface, toe. further groundwater drainage scheme. found that: • instability. pressures because locations. intercept effectively embankment stability.