GROUND IMPROVEMENT TECHNOLOGY

- STONE COLUMN TECHNOLOGY- BAND DRAIN TECHNOLOGY

C-PHI | GEOTECH

ALTERNATIVES FOR INADEQUATE GROUND?

Abandon the site and locate the structure elsewhere

Design deep foundations to carry the weight of the structure to competent stratum

Redesign the structure according to the ground conditions

Improve the properties of the ground prior to construction

BASIC PRINCIPLE OF GROUND IMPROVEMENT

Densification of the ground , E.g.: Compaction Accelerate the consolidation, E.g.: Vertical drains Usage of geo synthetics, E.g.: Geotextiles Usage of admixtures, E.g.: Cement stabilization Preloading Mechanical Stabilization

Ground improvement is the modification of the ground properties in order to achieve the required ground conditions for the particular use of the ground.

BAND DRAIN TECHNOLOGY

BAND DRAIN TECHNOLOGY - PVD

Used in loose, compressible and water saturated clay and silty clays.

Soils are characterized by very loose skeleton and a large pore sizes filled with water

Requires about ten or more years to consolidate on preload.

PVD – Prefabricated Vertical Drain.

WHAT IS VERTICAL DRAIN? Consolidation takes

place in only one direction

Vertical drainage path may be substantially longer

It may take 10+ years to consolidate Pore water will flow laterally

Pore water pressure dissipates as the layer drains and water is conveyed through vertical drains

It takes only about 6months or so to consolidate

COMPONENTS OF PVD?

Core : It is called drained body corrugated, flexible and made of polypropylene, designed to provide high discharge capacity, high tensile and compressive strength.

Filter Jacket: Non – woven ,thermically bonded polypropylene wrapped around the core. Acts as the filter to allow ground water to the core.

Filter

Core

ADVANTAGES OF BAND DRAIN TECHNOLOGY:

Minimum disturbance to the soil layers during installation

High water discharge capacity High tensile strength prevents the

collapse of flow path. Fast and easy installation Deep installation up to 40m.

CASE STUDY: INSTALLATION EQUIPMENT

Hydraulic Stitcher Mandrel Base Hydraulic Machine

CASE STUDY: BAND DRAIN INSTALLATION

CASE STUDY: BAND DRAIN INSTALLATION

After the installation of band drains, Casagrande peizometer and plate type settlement recorders where installed in order to check the settlements

CASE STUDY: BAND DRAIN TECHNOLOGY

THANK YOU!

For more information, Please contact:

C-PHI | GeotechWebsite: www.c-phi.comEmail : cphi@c-phi.com