Gravel bag and method for protecting and exit point for stormwater

Abstract

A gravel bag manufactured from a single layer of a heavy-duty geotextile composite material (also referred to as “geo-composite”), said layer comprising a closure device resistant to opening as pressure is applied from within. The geo-composite material is formed by affixing at least two fabrics that together complement each other's performance. The overall structure allows for a single composite geotextile fabric that is low-slip, low cost, offers effective padding, has a high tensile strength, is puncture and tear resistant, and that has low elongation properties. In use, the single layer geo-composite gravel bag significantly outperforms all other single layer and multiple layer geo-composite gravel bags currently in use.

Description

RELATED APPLICATION[0001]This application claims priority from U.S. provisional application with Ser. No. 60 / 848,462, which was filed on 29 Sep. 2006, and U.S. provisional application with Ser. No. 60 / 898,078, which was filed on 29 Jan. 2007. The disclosures of those provisional applications are incorporated by reference herein as if set out in full.FIELD OF THE INVENTION[0002]The present invention relates to construction sites, and particularly methods for regulating construction site stormwater runoff.GENERAL BACKGROUND[0003]The flow of water over land from rain, snowmelt, manmade means such as irrigation and other sources is termed “runoff”. Oftentimes, and more particularly at construction sites, the runoff rate exceeds the rate of water infiltration to the ground. Further, water that has infiltrated an up-slope portion of a hill may flow through the soil and exfiltrate from the soil further down, adding to the volume of runoff. Finally, because many construction sites are in ur...

AI Technical Summary

Benefits of technology

[0011]As a first type of bag, burlap or woven polypropylene bags can be filled with sand or gravel and are an inexpensive gravel bag solution. The drawbacks are that they break easily, and as few as 1 to 2 vehicle impacts can cause the sharp edges of the gravel to tear through them, or the seams or closure to fail, causing hazards and the added expense of maintenance and replacement. They also slip easily upon vehicle impact. Additionally, during the time when they are broken, the construction site may be out of compliance with local and federal regulations, potentially subjecting the construction site to heavy environmental fines. The advantage to this method is that they bags are very inexpensive, and if vehicular traffic is light enough, they can be replaced cheaply on an as-needed basis.

[0012]Second, gravel bags made from woven or knitted geotextile materials may be used. These bags are generally made from a single layer of 4 to 6-oz per square / yard knitted or woven fabric. These bags are stronger than their burlap or woven polypropylene counterparts. They too fall short in vehicular traffic areas, breaking after between 1 to 10 vehicle impacts. In these bags, a lack of padding allows the edges of rock to tear or cut through the fabric upon vehicular impact. Another drawback to these bags are that they slide easily, allowing the bags to move out of place, and also generating dry friction that may lead to premature breakage and similar environmental problems as described above. The life-span of this type of bag is on the order of a few weeks to a month in high traffic areas.

[0015]It is thus an objective of the present invention to provide for a high strength gravel and durable gravel bag that is able to withstand the vehicular impacts associated with high traffic areas.

[0016]It is a second objective of the present invention to provide a means for closing a gravel bag that will not be destroyed by the vehicular impacts associated with high traffic areas.

[0017]It is a third objective of the present invention to provide a gravel bag less prone to slipping out of place than conventional gravel bags.

[0018]It is a fourth objective of the invention to provide the above objectives through a simple and low cost design.

Problems solved by technology

Further, water that has infiltrated an up-slope portion of a hill may flow through the soil and exfiltrate from the soil further down, adding to the volume of runoff.

Sediment and any other pollutants picked up by runoff are washed downstream, often causing environmental damage, ecosystem disturbances, aesthetic problems, and even groundwater contamination in the process.

It can be expected, then, that multiple crushing impacts will be generated on the gravel bags by these vehicles.

Because gravel bags are typically filled with crushed aggregate (gravel), which is often very abrasive, jagged, and sharp, the wear on the bags is quite high.

Friction from the sliding effect of vehicle traffic is also a major contributor to gravel bag failures.

When a gravel bag fails, it can cause crushed aggregate and material trapped in the bag to spread around the area, which in many cases is a city street or even the drain inlet sought to be protected.

Materials discharged down a drain inlet and into waterways cause even more destruction.

The cost to constantly replace such gravel bags is high.

Conventional gravel bags are also prone to slippage from contact with vehicles, displacing the bags from their desired location.

Even the smallest of gaps can cause the gravel bags to become completely ineffective in this regard.

Because conventional gravel bags are slippery in nature they can be easily moved by contact with vehicles and construction equipment.

Even if the bag does not fail as described previously, it may be displaced, causing a street hazard and allowing sediment to wash into a drain inlet.

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