湖南方运重工科技有限公司 HUNAN FAE HEAVY INDUSTRIES CO.,LTD. TOGETHER WE FORGE AHEAD

Vertical Drains installation rig

Overview

Information  details

 

PVD rig,preformed vertical drains installation rig, also referred to as wick drains. These are themodern equivalent of sand drains and can be used in conjunction with surcharge.PVDs may be used in a variety of applications to accelerate the settlement insoils, to form a path for the extraction of gas and leachate.

To accelerate the settlement process and decrease in water pressure it is crucialto shorten the path of the pore water. This can be achieved by the installationof vertical drains at regular intervals from each other into the sub-soil. Dueto the installation of vertical drains, the overstrained pore water pressurecan flow horizontally to the nearest drain and subsequently flow freely throughthe drain to the ground level. By using vertical drains, the consolidationprocess usually is reduced from decades to a half year or less.

 

                       

 

   

    

 

Applications

Ground improvement with verticaldrains is applied in numerous projects. Typical applications are summarizedbelow:

- Construction of roads, railways andairports 
- Land reclamation projects 
- Port Construction 
- Dyke Construction 
- Residential and industrial areas

 

Benefits

The advantages of the system PVD are:

- Guaranteed drainage, even with largedeformation and soil pressure 
- Drain system can be modified to the applicable soil conditions 
- Drains can be installed to great depths, i.e. deeper than 45 meters - Minimaldisturbance of the different soil layers 
- Dueto large production capacity very large volumes can be delivered in a shortperiod 
- Because of flexible core and the flat filter, PVDs is the favorite drain of theuser, namely the driver of the crane 
- Certified and high quality production process. 

 

Filter membrane

The filter membrane has an important keyfunction. It consists of thermally-bonded polypropylene fibres with a randomstructure, known by the tradename Typar. Contrary to woven materials thatprovide a straight passages through the filter structure, through wick soilparticles can force their way, the filter has a random structure which enablesthe filter to restrict the movement of the soil particles and to preventclogging. In general a filter is required that prevents clogging by soilparticles but that is sufficiently permeable. PVD's filter structure meets theserequirements. When the compressible subsoil contains horizontal soil layersthat are very permeable, pressurised pore water will seek out these layers anduse this route to the closest drain. In order to optimise the use of thesepermeable layers the permeability of the filter must be at least as high as thepermeability of these layers. PVDs has a filter with a high relativepermeability level enabling effective drainage in layered soils.

 

Other importantrequirements that a filter needs to meet are:

- high mechanical strength

- high resistance to bacteria andmicro-organisms

- resistant to acids, solvents, etc

- no loss of strength over a prolongedperiod

- creep resistant also under highpressure.

 

Technical Specifications 

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