DBS Glass fiber quartz cable duct and DBD composite glass fibre reinforced plastic cable duct together with special-purpose attachments can be arranged into multilevel conduit systems according to different engineering requirements. The suitable construction fields are as followed

General occasion:
 1、City electric wire network constructions and improvement projects
2、Municipal improvement projects 
3、airport constructions
 4、The industrial and civil community constructions
 5、Traffic constructions

Special occasion:
1、Protect cables when buried in the roads or across the road junctions.
 2、Protect cables when buried in the special environment such as the bridges, the rivers .
 3、Used in power plants, transformer substation in order to prevent step step voltage lead to the fact danger to people and animals.

The constructing measures are as followed：
1、The excavation of the  Cable ditch 2、foundation of the cable ditch 3、Disposition of spacers 4、Connection and laying of the ducts 5、The covering of backfill soil

1, the excavation of the cable ditches
   Width W and depth H of cable excavation ditches should satisfied the requirements of the number of layers and rows of the cable ducts. Generally speaking, the distance H1 cant be less than 500 mm.

2, the foundation of the cable ditch
   Underground ducts always bear the covering soil loads and external loads such as vehicles and goods.
So the foundation of the cable ditch should be given strong attention, the bad foundation will cause z shape in duct shift and local stress convergence, which threatens the security of the cable.  

A.In the general soil location
   Only a layer of 50-100 mm sands or concrete should be paved at the bottom of the ditches.

B.In some worse soil location
    Pave a layer of 50-100 mm sand or concrete under the spacers, press it closely in order to prevent the sinking of spacer s in no regularly.

3, disposition of spacers
   The cable ducts in the underground are usually arranged into multilevel layers. In order to support the multilevel layers of cable ducts, special spacers are designed and produced. The installation manner and number of spacers should accord to installation environment and design specifications.

4, Connection and laying of the ducts
   Lubricant can be used for easy insertion; lubricant should be neutral solution or soap spuming. Don,t use the oil with the lubricating grease, or the rubber will  be fatiguing .

1、Clean the internal and external surface of head of connection of the ducts, ferrule the seal and enclose according the oblique tooth.

2、Align the seal well duct and the head of the duct which is ready for connection ,then cushion with plank in tail of duct ,beaten with the medium-sized hammer.

5 ,The covering of backfill soil
Fill with backfill soil around duct and press it closely from bottom to top ,so as to prevent bad backfill cause road surface sink and z shape in duct shift.