Case Study On Slope Failure 3u422b

SLOPE FAILURE

PRESENTORS ABD HAMID BIN MOHD NAJILI MUHAMMAD SYAZWAN BIN KAMARUZZAMAN NAZLI BIN ABU BAKAR FIRRA BINTI A.ROSLAN

What is Slope Failure? 

 

The downslope movement of rock debris and soil in response to gravitational stresses. Also referred as Mass Wasting. The types of movement:  Falls  Slides  flows.

Factors affecting Slope Failure   

Triggering Events Water Gravity

How to prevent slope failure? Improve slope drainage.

Attaching the slope material to bedrock with physical restraints (e.g., chicken wire, cement, or rock bolts).

ing the base of the slope with retaining walls.

Planting vegetation on the slope.

Case Study Rakyat Corporation Sdn. Bhd. requested PB Geotechnique to carry out assessment of slope failure at “Project Development at Saujana Impian, Kajang.

Objectives To determine the potential causes of the slope failures. To gather as much information with regard to the geological and subsoil information. To obtain relevant soil parameters for slope assessment studies.

Scope In-Situ Soil Investigation. • Field works comprising of boreholes. • Laboratory test on disturbed and undisturbed samples recovered from boreholes.

Geotechnical Assessment. • Site observation. • Slope stability assessment.

Laboratory Test o o o o o

Moisture content Bulk Density Atterberg Limit Particle size distribution Consolidated Immediate Undrained (CIU)

Results 

Constituents for Sandy Clayey Silt

Item

Description

BH1 (%)

BH2 (%)

1

gravel

3% - 32%

1% - 24%

1% - 8%

4% - 40%

1% - 31%

2

sand

11% - 35%

7% - 17%

5% - 34%

7% - 29%

3% - 19%

3

silt

20% - 52% 49% - 71%

48% - 80%

24% - 50%

33% - 76%

4

clay

8% - 34%

9% - 24%

7% - 23%

17% - 26%

10% - 50%

BH3 (%)

BH4 (%)

BH5 (%)



Summary of F.O.S

Item

Description

Result of slope stability (F.O.S) water far from slope

1

water near slope

slope stability analysis for CH 20 soil profile BH 5 Soil parameter from CIU BH3

2

1.129

0.749

soil parameter from CIU BH 2

1.194

1.03

soil parameter from CIU BH 3

1.264

1.1

1.149

0.917

slope stability analysis for CH 40 soil profile BH 2, BH 3, BH 4

3

slope stability analysis for CH 65 soil profile BH 1 soil parameter from CIU BH 1

Conclusion Assessment are based on the site observations, field and laboratory investigation and slope stability analysis. The failure could have been caused by the presence of water infiltrating into the slope.

If F.O.S is less than 1.0, slope failure is expected or unstable. The sources of infiltration could have been through: • • •

The open platform at the top of the slope. The earthdrain at the top of the slope. Leakage in water pipe at the top of the slope.

Pictures

The End