Nonwoven geotextile is widely used in highway constructions and drainage works. Installed respectfully, it should perform better and longer; installed wrongly and it may literally take the rough end of the stick in respect of its function and of all the advantages that derive from its ability to provide filtration and separation and also for its strength.
A few notes below on what to bear in mind when installing such products, and the steps to be taken in all similar works.
Prepare the Subgrade before Laying
A clean, unencumbered subgrade is what you aim for. Sharp stones, roots, rubbish of any kind should not be in the fabric’s way on this journey. The earth also should be well levelled; wrinkles or folds should not be allowed to develop, and neither should it be so harshly treated as to cause undue stressing of the underlying fabric. The smooth clean bed is what you want — the more so for it is there that the geotextile will work for you better from as close to the word go as makes no odds.
Soften up under the layers of soft subsoil, compact off well. Compaction raises the design bearing capacity, reduces the risk of unwanted settlement. Too firm ground however and you chase the natural vertical drainage paths that exist in the earth strata.
Make your own selection of geotextile
Further as to specification. Not other people’s requirement, yours. What takes your fancy? You are thinking now in terms of tensile strength, of permeability, of CBR puncture resistance. Couple this with the procuring of the drainage works, and only a merchant that has them will take your order! Trouble being that it takes how long to cut one to flow through, no final answer is there. Best here would be to take the biggest flow rate goingIf for road separation, you want more of the fabric related tensile strength, than anything else, your requirements should, anyway, include how things actually are in your project.
UV resistance is needed by tropical and equatorial users. Developers on that latter side, Whichever feature helps give the geotextile a longer life in direct sun exposure, cannot compensate for bad design or works, totally.
Method of proper Rolling and Positioning
Have you given it proper thought, method of “roll out on the ground”? Care must be taken to roll that surface on the ground, without dragging roller on sharp fixture or rough ground,-or too extensively rough ground. No inclusions or other deformities likely to lead to tearing with chance of unrepaired extensive damage to the fabric.
Also, ensure seeing that the fabric is being laid out flatly and away with the wrinkles. Wrinkles might entail the load not undesirably being distributed in the works as it should be. Always overlap adjacent rolls as much as project details dictate the outcoming geotextile; commonly apply between 30cm and 100cm. In soft soil conditions, you however may require to make larger overlaps to forestall large area settlement.
Jointing of the Geotextile, Adequate Fixing of Geotextile
Be not moving with roll out and get it tie firmly down to the earth once laid; it might easily be displaced, Machines would work on until to your loss ere anybody might be availed to rescue it. Use U-shaped pins once you see it sewed or glued edges of the material, so as to hold the fabric in position against wind or possibility of machinery passing
Stronger joints of heat bonded or even by sewing should sometimes apply in the course of engineering works where you need to hook together two or more pieces of the geotextile. In high tensile works, maximal welding will be a necessity; but normally, at least needle connects will be the feeling of the field.
Environment
Topography tells you how the fabric should readily allow drainage pass through core of final work. A bad sew joint, might leave something to be desired, and your end performance would underperform, in terms of both being allowed separation and filtration.
Backfilling and protection (layer) control
For the savvy, being almost terse, all we are saying is take care the while laying; by using soil, as warned. Start with reasonably fine in first layer. Loading big stones here and there on it during reed orifice fill, will hardly help matters.
Equipments should be driven in with low ground pressure in the works; your chances of puncturing it will be drawn through to it and so forth, and minimize that way. But fill in with more earth and less stones anyway.
Common Mistakes
Lay out your earth for on it expect to still do right by it. Lay awful joint on two pieces of the earth; and all on its gone in your works system, then lament. Making contact with the fabric and sharp aggregates will after to puncture it, leave you a headache before the project moves an inch!