Computer aided design of reinforced earth retaining walls

A computer program has been developed for design of earth retaining structures using different types of reinforcements. The program enables to achieve on optimum design.

Landslide hazard zonation maping

Based on landslide hazard zonation studies carried out in Sikkim area and on Kathgodam Nainital Highway, landslide hazard zonation maps have been prepared to evolve a suitable maintenance management strategy to keep the hill slopes along the roads, free from landslide problem.

Ground improvement techniques
  • Use of vertical sand drains/sandwicks

    Vertical sand drains / sandwicks combined with incremental preloading have been successfully used to increase the bearing capacity of soft clay deposits by accelerating the consolidation of the clay layer.

  • Use of stone columns
    Two types of stone columns namely, composite column and reinforced columns have been designed to improve the bearing capacity of soft clays and were applied in port areas for specific field application.

  • Lime slurry injection

    Lime slurry injection technique has been developed to economically improve the performance of inadequately compacted earth fills for strengthening. Bore holes are made into the fills and lime slurry is injected under pressure through these bore holes. The requisite injection equipment and technique have been used successfully. Compacted lime piles into 10 cm to 15 cm boreholes has shown to be effective in improving the embankment behaviour.

  • Use of geotextile

    Geotextiles and other synthetic materials like jute have been used for the construction of roads on weak subgrades. These materials are used as a separator, for drainage and for strengthening the pavement structure.

Use of jute geotextile for drainage application

Field instrumentation

To monitor the stability of weak and slide prone slopes, a number of indigenous geotechnical instruments have been developed. These instruments can also be used to monitor the performance of embankments and road. Instruments developed are:

  • Composite device for the measurement of differential settlements, tilt and crack width in buildings
  • A remote control settlement gauge
  • Settlement gauges (mercury type)
  • Strain guage pore water pressure cell
  • Pointer type inclinometer
  • Strain guage type inclinometer
  • Capacitance type moisture sensor
  • Heavemeter