01046333

Component

Mechanically Stabilized Earth (MSE) retaining walls have been increasingly used in many federal, state and private projects over the last 20 years. MSE wall are reliable, constructible, and cost effective. However, failure of MSE wall has become a problem for all agencies using them. This paper presents the case history of segmental block, MSE retaining wall located in Rockville, MD. The MSE wall was 15 ft high and was constructed using geosynthetic reinforcement. The backfill soil specified for the project was granular fill soils. The top of MSE wall moved about 12 inches to 18 inches. An extensive geotechnical investigation program was undertaken to investigate the MSE wall failure. The paper presents the results of the forensic investigations to determine the causes of failure and possible remedial measures. The computer program STABL was used for slope stability analysis, which shows a factor of safety less than 1.0 for partially saturated conditions. Two test pits were excavated to check the soil and geogrid conditions and was found that geogrid reinforcement were not horizontal. Based on site investigation, test pit results and stability analyses, it was concluded that the wall failure was caused by a combination of factors: improper geogrid installations, inadequate compaction of reinforced soils, and inadequate internal drainage of backfill soil.

01042056

07-0450

English

20p

2007

Transportation Research Board 86th Annual Meeting

CD-ROM

Figures; Maps; Photos; Tables (1)

Backfill soils; Failure analysis; Geogrids; Geosynthetics; Geotechnical engineering; Mechanically stabilized earth; Retaining walls; Slope stability; Soil compaction

Reinforced soils; Site investigation

Rockville (Maryland)

Geotechnology; Highways; I42: Soil Mechanics

Transportation Research Board Annual Meeting 2007 Paper #07-0450

TRIS, TRB

Feb 8 2007 5:02PM