Soil reinforcement:Materials and design questions

- Possible materials for soil reinforcement

Most used:

• STEEL
• POLYMERS (PET, PP, PE-HD, AR, PVA)

- Main design questions:

• What are the soil-reinforcement interaction parameters ?
• What is the long term design strength (TLTDS)of the reinforcement ?

Advantages of using uniaxial geogrids in reinforced soil retaining walls

Advantages of using uniaxial geogrids in reinforced soil retaining walls, can be listed as follows:

• Fast construction in all weather conditions
• No mortar, dry built
• Optimal utilization of land
• Free design support (almost all the companies supply)
• Aesthetics: impressive & stylish designs
• Versatility & flexibility
• Cost efficiency
• Durability, resistance to environmental influences
• Accredited by independent testing laboratories
• Minimal maintenance

Drainage- retaining wall-geocomposite sheet drain

To prevent the water pressure behind the retaining walls a drainage layer is generally needed. The convetional method is to use gravel behind the wall and leave some holes on he wall. The water leakage from these holes causes bad view . And sometimes the gravel may be expensive with the transportation costs.



One of the easiest methods is to use geocomposite drainage sheets.



In this project seen on the pictures a geocomposite drainage sheet have been used. The drainage material was made of a 3 dimensional drainage core which lets water go to any direction and a special filter which is resistant to clogging.



The drainage layers were installed vertically by simple methods. They nailed.



The most important thing is you should pay attention to the overlap direction. Because if you start backfilling with the help of a heavy machine like an excavator the overlaps should look to the opposite side of backfilling.



If you backfill from the front (directly on the drain) there is no problem.

Retaining wall drainage with geocomposites

Behind the retaining walls we need drainage and filter layers to carry the water to the drainage holes or to the drainage pipes at the bottom.

In traditional methods we generally use gravel or sand as drainage layers.

Especially in residential areas the leakage water coming out off the holes of retaining wall doesn't wanted. It is not very good to see some muddy water and the stains of water.

Geocomposite drains are used behind the retaining walls to carry the water from the soil to the drainage pipe.

Geocomposite drainage products replaces the drainage and filter layers. So, it is better to transport to construction site a lightweight material and install it.

Geosynthetic drainage sheets should be manufactured by good quality filters to prevent clogging and also there should be a three dimensional drainage layer between the filters.