Geotechnics, Transport and Geospatial Laboratory

Geotechnics Laboratory consists of four units: Soil Mechanics, Engineering Geology, Geotechnics Research laboratory and Workshop. There are four technicians with background ranging from civil, mechanical, electrical and electronics. The Geotechnics laboratory occupied a total area of approximately 1154 square meters.

Soil Mechanics Unit is used primarily for teaching and routine soil testing. In addition to conventional test apparatuses for soil classifications, compaction, permeability, shear strength and consolidation, models to illustrate the principles of effective stress, seepage, liquefaction and earth pressures on retaining wall are also available.

Engineering Geology Unit stores a wide collection of minerals and rock specimens. Equipment for rock testing includes porosity determination, hardness, slake durability, swelling index, ultrasonic, point-load, Brazilian and four-point flexure. Also available are structural geology models, a base friction model, stereographic projection models and rock wedge models.

Geotechnics Research Laboratory supports mainly research activities. Most of the specialised equipment in the Geotechnics Research Laboratory was designed in-house. The equipment includes triaxial and direct shear apparatuses for unsaturated soils, triaxial permeameter for unsaturated soils, K₀-consolidation apparatus for unsaturated soils, null-type axis translation apparatus, cyclic triaxial and cyclic simple shear apparatuses, pressure plates for different suction ranges, various soil suction measurement devices, automated oedometers with pore-water pressure measurement and constant-rate-of-strain apparatuses.

Geotechnics Workshop houses in-situ testing equipment and field measurement instruments. Major equipment include drilling rig, ram sounding apparatus, weight sounding apparatus, piezocone, mechanical and electrical cone penetrometer rig, self-boring pressuremeter, borehole pressuremeter, flat dilatometer, field vane, borehole shear tester and continuous surface wave system. Major measuring instruments include inclinometers, settlement probe, load cells, piezometers and distometer.

It also provides space for large-scale model tests. Some of the supporting facilities for model tests include large soil mixers, consolidation tanks for sample preparation, a 100-tonne compression rig and a 10-tonne overhead crane. The increase in research activities has necessitated an expansion of research facilities into the Geotechnics Workshop. The research equipment housed in the Geotechnics Workshop include rock specimen preparation equipment such as grinder, polisher and rock cutter, a 300-tonne triaxial compression machine for rock testing, direct shear test for rock, hollow cylinder apparatus, direct simple shear apparatus, vertical drain testers, triaxial apparatuses and oedometer.

Geotechnics Laboratory supports research in the form of undergraduate final year projects, postgraduate research projects and funded research projects in geotechnical engineering. Major research projects completed to date include lime and cement stabilisation of soft clays, behaviour of bored piles in residual soils and weathered rocks, stress-deformation and strength characteristics of fabric-reinforced earth, use of flat dilatometer test for soil investigation, behaviour of sand columns in soft clay, fabric-reinforced retaining structures, performance of embankment piles in soft ground, rainfall-induced landslides, characterization of the Bukit Timah Granite, and strength improvement of peaty clays.

Current research projects include consolidation of clay slurry using vertical drains, strength and deformation behaviour of Singapore marine clay and residual soils, land reclamation, ground improvement and beneficial use of waste materials, soft ground tunnelling, rock engineering in underground construction, unsaturated soil behaviour, use of capillary barriers and dynamic behaviour of soils, monitoring of unsaturated slopes and application of unsaturated soil mechanics to stability of trees.