Loss of slope stability on railway tracks and its sanation · Loss of slope stability on railway tracks can be prevented mainly by: knowing the natural conditions based on quality

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Loss of slope stability on railway tracks and its sanation

Petr

Černoch

AGE a.s. -

applied geotechnics and ecology, Czech Republic

XVIII EYGEC, Ancona

/ Portonovo, Italy –

June 17-20, 2007

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Structure of the lecture

Description

of each case

location – maprailway track – cutting / embankmentgeology – profile / conditionslandslide – causessolution – sanation

Case studies

based on experience in situ

JenišovČeské BudějoviceVeselí n. Lužnicí

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1. JENIŠOV –

locationsouth west of Bohemianearby border with Austriaalongside water reservoir Lipno

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1. JENIŠOV –

railway track and geologyrailway track – cutting

800 m long5 to 7 m deepinclination approx. 45°

geological profile – km 61.900; EC-7humic soilclayey sands with fragments of bedrockbedrock – biotitic gneisses and granulites

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1. JENIŠOV –

landslide causesoriginal drainage system damaged in the course of time

winter 2006 – heavy rains=> water accumulation between

sands and bedrock

photo: P. Novotný photo: P. Novotný

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1. JENIŠOV –

sanationsetting up a gabion retaining wall recovering the drainage system

(drain ribs, ditch)

photo: P. Novotný photo: P. Novotný

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2. ČESKÉ

BUDĚJOVICE –

locationsouth of Bohemiamain connection between Czech Republic and Austria

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2. ČESKÉ

BUDĚJOVICE –

railway track and geologyrailway track – cutting

100 m long5 to 7 m deepinclination approx. 45°bottom – old retaining wall

geological profile – km 211.380; EC-7humic soilclayey gravel sands with bouldersimpermeable clays (stiff consistency)occasional springs

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2. ČESKÉ

BUDĚJOVICE –

landslide causesexcavation for cable harness

poorly compacted => water ran through the slope

and not on the surface

spring 2006 – spring thaw=> water accumulated above

underlying impermeable layers

photo: P. Novotný photo: P. Novotný

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2. ČESKÉ

BUDĚJOVICE –

sanationsubstitution of the old wall by a new gabion retaining wall

construction of a drainage systemrelocation of the cable harness

photo: R. Smolík

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3. VESELÍ

N. LUŽNICÍ

–

locationsouth east of Bohemiarailway track from České Budějovice to Pragueflat landscape with rivers and ponds

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geological conditionstertiary basin – flood plainsediments – kaolin clays, sandscovered by Qrternary sands, loams

railway track – embankment500 m longup to 4 m highapprox. 35° steep

3. VESELÍ

N. LUŽNICÍ

–

railway track and geology

photo: P. Novotný

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3. VESELÍ

N. LUŽNICÍ

–

landslide causesembankement body during floods

acts as a barrier / damwater flow possible through the bridges

in 1980s main bridge destroyed and filled up

=> during floods in 2002 and 2006 deformations appeared

photo: P. Novotný

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3. VESELÍ

N. LUŽNICÍ

–

sanationplan

surface water-protectionconstruction of a small culvert

realityonly embankment body restorationproblems will probably last

photo: P. Novotný

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Conclusions

Loss of slope stability on railway tracks can be prevented mainly by:

knowing the natural conditions based on qualitygeological research

designing the right technological procedures

complying with them throughout the construction

maintaining the existing drainage system

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Thank you for your attention

ContactPetr ČernochAGE a.s., Czech Republiccernoch@age-as.cz+420 222 714 962 AGE a.s. - applied geotechnics and ecology