LOCATION : Bangkok, Thailand

CLIENT : Department of Highway ,Thailand (DOH)

PERIOD OF SERVICES:

Geotechnical Instrumentation: May 2006 – April 2007

CAPITAL COST : 600,000.00 Baht

FINANCED BY: N/A

ASSOCIATED FIRMS: N/A

DESCRIPTION OF PROJECT:

Kaketsart and Laksi Underpass, the open tunnel, originated by Department of Highway (DOH). These underpasses are constructed on soft clay layer with high compressibility. The excavation in a thick layer of Soft Clay during construction may result in ground movement that possibly causes damage of the structure as well as malfunction of flyover bridge in the vicinity. Therefore, the ground movement and uplift pressure acting on wall and basement of the underpass may result in the damage. To monitor and approach these effects, Department of Highway (DOH) is objected to monitor these effect to deal with the possible movement and to improve the design in future project.

SCOPE OF SERVICES:

• Supplied and installed the following instruments:

• Inclinometer to monitor magnitude and rate of ground movement in lateral direction

• Pneumatic Piezometer to assess the insitu pore pressure distribution

• Vibrating wire strain gauge to monitor stress distribution on wall

• Observation well to monitored ground water level

• Surface settlement plate to monitor surface settlement

• Monitoring work and interpretation report

• Analysis the instrumentation results using geotechnical Finite element program

KEY FACTORS:

• The data is used to verify the design assumptions and to check that performance is as predicted

• The monitoring results are assessed how the construction can proceed without risk of failure and perform proper function in long term period.

• The monitoring results provide the early warning of impending and/or critical failure,

• Improve the remedial methodology.