Introduction

The effect of ground conditions on the civil engineer’s work is seldom favourable. The carry speeds are rapid, and unless attention is paid to the presence of substandard soil, or the risk of subsequent erosion, or the speed of traffic anticipated, lasting damage is likely. Thick aggregates, or even reinforced concrete, can overcome such defects, but the cost and time incurred are not conducive to these remedial measures together with possible ecological consequences.

Geocell systems have taken advantage of these concerns. The geocell or cellular confinement system is a three-dimensional “honeycomb” structure, that when expanded, confines infill (soil, sand, gravel). What may seem a simple device underlines a powerful method of preventing erosion as well as producing a more evenly distributed load.

Key Explanation

The way a geocell works is simple to explain. When the device is expanded, and material placed within, the effected cells form mutually-supporting structures which tend to “transfer” the weight load sideways backwards.

The effect is to:-

• raise the shear strength of soil.
• restrain its tendency to move sideways and displace.
• reduce (considerably) settlement taking place, particularly when beneath a “soft” sub-layer.
• produce a more stable structure.

Going further, a “geocell” provides true three-dimensional confinement rather than just two-dimensional, in contrast with the gealat “flat” geosynthetics. This feature comes into consideration when utilising the geocel where soil slippages problems may arise, notably, for instance, a slope, or unmade road construction. Other details like perforated and textured surfaces in conjunction with HDPE “high-density polyethylene” result in better-but-stronger friction extremes, even more so in the joined, long strands of material. There, ultrasonic welding causes adjacent geocells to strongly tie as together and withstand downward thrusts from repeated, loaded, vertical impulsive loads. In summary, strata of bedrock may be reached with lower lateral thrusts, and soil displaced to occupy adjacent but entwined geocell “helps prevent settling or, future slippages”.

Applications / Use Cases

Geocell systems may be used in a full range of civil engineering applications because of their flexibility and effectiveness.

Slope Protection
Placed on the face of embankments and in other steep applications, the geocells control the erosion of soil from the surface layer; vegetation may also be allowed to grow in the cells, contributing additional stability and attractive vegetation.

Erosion Control
In water flow areas, aka channels, shorelines, etc. geocells serve to slow the velocity of water and keep soil intact.

Load Support/ Base Stabilization
Use on roadways, driveways, parking lots, construction pads and the like, geocells distribute the load across the top more evenly – thus eliminating need for thick base layers and creating a positive long use on weak soil.

Retaining wall
A gravity retaining wall may be built with geocells. The system is flexible and retains its ability to keep form.

Access roads/drives
Temporary and permanent access roadways and drives may be built employing this geocell system, minimising aggregate use, and retaining service with repetitive traffic.

Comparison or Advantages

Such systems are considered efficient in relation to providing traditional systems.

Cost efficient
Reduction in imported aggregate, and excavation, etc. lower project costs

Rapidly installed
Lightweight and despatchable. Easy installation with minimum heavy equipment.

Environmental value
Lower use of materials, and can use native fill minimises foot print. Environmental applications tend to encourage the green.

Durability
A good geo-cell is tough enough to withstand UV, chemicals, and mechanical abuse. Accordingly, it can see years of service.

Versatility
Sometimes they make the best roadway, sometimes riverbank and more.

How to Choose / Buy

There is no best option for geo-cell because there are so many different uses and site conditions. Use high-cell heights on heavy duty applications and lower heights for erosion control. You may consider textured and perforated surfaces for added friction and drainage.

Welding a geo-cell is important and using ultrasonic welding provides strong seams capable of laps under constant strain. You may further consider cell heights and panel size as features impacting coverage. Additionally, there is the hovering issue of a competitive source for consistent quality, certifications, support, and technical information. Buying per m2 is easy but be careful that you’re only doing yourself a fav r. The lowest price will oftentimes cost you more long-term.

FAQ

What is this?
It is a three dimensional cellular confinement system; a geo-cell, of polymer materials that can be used in the civil engineering industry to stabilize soil in order to increase load bearing capacity.

How does it work?
It confines the infill material inside the cells and becomes a stable layer; we create a sandwich or layer stacking arrangement between this stable layer and the pore soil, the latter is not fortified and would tend to move if unfettered.

Cost or lifespan?
Materials costs will vary depending on the basic product, height, terrain specifics, size and volume, etc. A minimal maintenance system with a 30 year life would be the goal for a high-quality HDPE geo-cell system.

Best option?
For heavy transport loads; high strength imports, textured and perforated goods. Greater cell height may be advisable. Control erosion with adequate cell weights for containment.Common issues?
Or errors perhaps? Actually; poor installation of the cells, inferior goods, or incorrect products; avoid lapses in design criteria or specifying.