Patent Application
20110280659
The invention relates to ballast block system for subterranean basins and chambers, and more particularly, to an interlocking ballast block system.
Grinder pump and STEP (septic tank effluent) stations have been manufactured in fiberglass and high density polyethylene (HDPE) basins for over 40 years. The most recent basin material used has been the HDPE ribbed pipe material similar to that used for storm water drainage culvert pipe.
All of these pump stations are designed to be installed in the ground with exception of a few indoor stations that may sit on the basement floor or in some cases must be installed below ground within the basement level. These stations are made of molded or welded pieces of molded sections of HDPE material. This material is used because it is easy to shape and mold, it is non-corrosive and has a very long life expectancy. The HDPE material provides for a very light weight basin that is easier and less costly to produce, ship and to install. Therefore, most of the grinder pumps and STEP pump basins require anti-flotation ballast to be added to the weight of the station to overcome the uplift forces of a wide range of potential groundwater levels.
Manufacturers of these stations have developed very detailed instructions regarding the proper amount of ballast required in size, shape and weight. These instructions are provided to installers of all ranges of capabilities to produce themselves after the product is delivered for installation. The ballast requirements are typically small quantities of less than 450 pounds containing less than 3 cubic feet of concrete material. The instructions describe a round form around the base with an outside radius of 36 inches and a height of 10.0 inches. The installer must provide such a form to manufacture this ballast ring in the field that will securely encase the shape of the pump basin.
Typical concrete used in the construction industry has a density of 150 pounds per cubic foot of volume. Uplift forces of ground water or ballast uplift forces are based on the density of water at 62.4 pounds per cubic foot. The resulting benefit of concrete is taken from the density in air value of 150 lb/cu. ft. less the density of water of 62.4 lb/cu. ft. This results in a net gain of 87.6 pounds per cubic foot.
The relatively small requirement of concrete for each station of less than 3.0 cubic feet poses a problem with regards to purchase of pre mixed or sometimes called ready-mixed concrete of uniform strength and consistency. Most concrete suppliers require a 5.0 cubic yard (135.0 cubic feet) minimum order. This then requires the coordination of installations of several pump stations at one time to meet this minimum order requirement, or coordination with other needs for concrete on the site. Concrete mixer trucks are able to get to most sites but are limited in access and can require greater care to reach a remote pump station location. Many pump installations occur in back yards with limited access that limits these trucks to reach the installation. Concrete must then be conveyed by wheel barrow or buckets adding to the labor effort.
These added costs and coordination will most likely force the installer to seek other means such as pre-mixed bag mix which requires field mixing and handling. Special care must be taken to assure proper mixing and uniform consistency of the material to provide the proper compressive strength concrete to reach the required ballast results.
Varying soil conditions and groundwater conditions make the forming of earthen forms of the precise shape and dimensions problematic. This can greatly impede the proper placement of concrete ballast that is of sufficient size and combined strength to properly secure these basins. Installers are often times faced with the challenge of how to secure the station from uplift forces during the time required for the concrete to set or cure to proper strength to complete the excavation. This can result in a great deal of extra time for manpower and machinery needed to complete this pump station installation.
Pouring a wider concrete earthen area can result in a negative gain unless additional concrete is also provided to offset the density of water forces described above. This method of installation is more costly with added concrete material needed and typically requires more time and handling of this added material.
The manufacturer's ballast computations allow for the weight of the backfill soil on top of the concrete ballast ring. This then requires the concrete to be fully cured to provide the strength to secure the pump station. This is especially critical if the station is installed under very high groundwater conditions. Uplift forces on the station can be imposed almost immediately after the station is backfilled. In such systems it is, therefore, imperative that the ballast ring be secure at the time of installation. This condition will require that the ballast ring be pre-cast onto the station prior to installation.
Many attempts at field constructed forms have been used by industrious installers. These forms can be made of wood, plywood, concrete well tiles, sections of plastic (PVC) pipe or HDPE or corrugated metal pipe have also been used. Some of these forms are made to be reused and others may be left in place. These methods can be very successful if done with care and attention to detail. They all require added time, manpower, and equipment to be completed. These measures are best taken well in advance of the actual installation and require pre-planning by the installer. Concrete typically requires a minimum of 7-14 days to reach proper strength to permit the movement of the structure. There are special add mixes and variations of concrete materials that can be used to increase the strength and reduce the set time. These materials are not commonly found at typical building supply and hardware outlets. These materials also require special knowledge and expertise to properly achieve the desired results.
Pre-casting a concrete ballast ring in controlled environments requires a means or method to then lift the entire structure of ballast and pump station and transport them to the installation location. Lifting hooks of sufficient size are required to provide strong lift points that are balanced and stable to support the pump station. Added concrete is usually required to provide support for this transport of the combined structure.
When properly made, a pre-cast ballast ring can greatly expedite the actual field installation in a wide range of soil and groundwater conditions. The pre-cast ballast ring provides the immediate advantage of securing the station as soon as the backfill soil is placed and compacted in sufficient manner to meet the manufacturer's requirements.
What is needed, therefore, are techniques for precasting of ballast rings in safe, readily installed configurations.
One embodiment of the present invention provides a system for providing ballast to an at least partially buried preformed chamber, the system comprising: at least one ring formed of a plurality of interlocking ballast block ring segments; each ring segment being configured with at least one male interconnect and at least one female interconnect, each female interconnect being configured to receive a corresponding male interconnect, each ring segment comprising a containment form shell and cast mass; and corrosion resistant locking pins whereby each female interconnect is secured to the corresponding male interconnect.
Another embodiment of the present invention provides such a system wherein the containment form shell comprises high density polyethylene.
A further embodiment of the present invention provides such a system wherein the containment form shell comprises composite resin PVC.
Yet another embodiment of the present invention provides such a system wherein the containment form shell comprises a blow molded thermoplastic resin.
A yet further embodiment of the present invention provides such a system wherein further comprising a placement handle.
Still another embodiment of the present invention provides such a system wherein the placement handle comprises a removable ring received in a lifting bolt disposed within the cast mass.
A still further embodiment of the present invention provides such a system further comprises a conforming profile disposed about an internal circumference of the at least one ring conforming to a sidewall of the preformed chamber.
Even another embodiment of the present invention provides such a system wherein the containment form has an aperture in a top wall for the introduction of casting material into the containment form.
An even further embodiment of the present invention provides such a system further comprising an indent in a bottom wall of each the ring segment formed by a projection of the bottom wall into the ring segment.
The features and advantages described herein are not all-inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and not to limit the scope of the inventive subject matter.
The invention is susceptible to many variations. Accordingly, the drawings and following description of various embodiments are to be regarded as illustrative in nature, and not as restrictive.
One embodiment of the present invention provides a means to achieve ballast containment while reducing the labor and time required of field constructed devices and to provide consistent product results and performance under varying installation conditions. Additional benefits of such an embodiment are to reduce work required in excavated trench locations to form and handle concrete materials thereby improving worker safety.
As illustrated in
The interlocking ballast block 500 may be formed in a shape to conform to the ribbed outer wall of the sewage grinder or STEP tank wall 300 to securely hold the tank from sliding upward under uplift forces of groundwater. A minimum capture of 2-3 ribs 502 and the base plate gussets 310 on the pump tank may be utilized to secure the pump to the interlock ballast block. The interlock ballast block will be sized to provide the same or greater ballast weight required by the manufacturer as well as provide the same or greater surface area to also enable the use of the soil backfill ballast as permitted by the manufacturer.
According to one embodiment of the present invention the interlocking ballast block will be able to be placed either on the pump before it is placed in the excavated trench or after it is placed. The interlocking ballast block will also be removable and re-usable if the sewage grinder pump or STEP pump chamber must be moved to another location. Removal of the interlocking ballast block will require the removal of the locking pins and then may be separated from the sewage pump chamber or STEP pump chamber by pulling them away from the pump chamber and separating the tongue and groove locking pin.
A lifting device 304 is shown in
An open top 402 in the ballast form allows the addition of concrete material either by others or as part of the manufacturing process. The concrete will provide the required weight for the ballast requirement as well as the support and strength to provide a solid block with the ability to support the pump basin from uplift forces and to provide the ability to permit placement of the ballast prior to installing the pump basin for installations under saturated groundwater conditions; or as a simple means to place the ballast at the top of the excavation. The ballast configured according to one embodiment of the present invention may be installed on the pump basin either prior to delivery to the installation site, at the installation site above grade or above the excavated trench area or in the excavated trench area provided proper safety measures are taken by the installer to meet OSHA and any other local trench safety regulations.
The ballast form configured according to one embodiment of the present invention provides a smooth outer wall form as well as a level base to sit evenly on the soil bedding material that is required by the manufacturer of the pump basins. The ballast form is designed to be a standard sized form made of injection molded or blow molded material such as PVC or HDPE or other suitable composite resin compilations. The form is not intended to provide the full structural support for the ballast ring and relies on the addition of uniform concrete mix material poured and properly vibrated to fill all voids in the mold. The ballast is intended to be a pre-cast product of specific size and shape which is prepared in advance of the installation of the grinder pump or STEP pump basin and is to be only used after the concrete is fully cured and of sufficient strength.
One skilled in the art will appreciate that other cementations or engineered materials configured with structural integrity may be used within the mold as ballast.
Various embodiments of the present invention are designed to permit stacking on wooden pallets for shipment as complete assemblies. The assembled ballast of one such embodiment may be shipped if properly secured on the wooden pallets as the unit weight may in some instances be expected to exceed 96 pounds (US).
The ballast forms (absent concrete) may be packaged in other suitable containers including stacking on wooden or plastic pallets, or containment in cardboard or plastic boxes provided they are secured and packaged in a manner to protect them from damage.
One embodiment of the present invention may be configured to surround fiberglass tanks or larger basins than those described above.
In one embodiment a stackable ballast block riser (described herein) shall be used to add additional ballast when required to overcome additional ballast forces or as additional support for stations that may require added depth of installation. In an alternative embodiment a second course of stackable ballast block riser shall be made to sit on the flat top surface of a first course of ballast block when the lifting hardware is removed. The second course of ballast block riser may interlock in the same manner as the described above ballast block and be designed to fit around the sewage grinder pump station and STEP or Septic Tank Effluent Pump Station by capturing an additional three (3) rows of corrugations. Additional courses of ballast block risers may be added as necessary.
The background (right) shows the internal form of the female molded form 1204 for the interlocking benefits of the system. Shown connecting to this form is the locking pin sleeve 1202 which is molded in a manner to allow ballast material to encircle the sleeve for support while maintaining proper alignment of the locking pin. This sleeve system is also used on the male end of the molded form. See
Also shown in the foreground is the molded hardware sleeve 1206 and anchoring nut and washer 1210 described in
Not shown in this detail is the added pair of grip nuts and washer described in
As illustrated in
As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the essence of the invention. For instance, the invention may be practiced as a system and/or method, and can be scaled. There is within the scope of the invention, a system for providing ballast to an at least partially buried preformed chamber, comprising at least one ring formed of a plurality of interlocking ballast block ring segments. Each ring segment may be configured with at least one male interconnect and at least one female interconnect, and each female interconnect being configured to receive a corresponding male interconnect. Each ring segment comprises a containment form shell and cast mass. Corrosion resistant locking pins secure each female interconnect to a corresponding male interconnect. The containment form shell may be fabricated from high density polyethylene, composite resin PVC, or blow molded thermoplastic resin. A placement handle comprising a removable ring received in a lifting bolt disposed within the cast mass is provided to aid in the lowering and placement of the ring segment. A conforming profile is disposed about an internal circumference of the rings conforming to a sidewall of the preformed chamber. The containment form has an aperture in a top wall for the introduction of casting material. The bottom wall of each ring segment may have an indent formed by a projection of the bottom wall into the ring segment. Additional rings may be stacked above the at least one ring to provide additional ballast.
Additional insulation rings may be further placed above the ballast rings. The insulation rings are formed of a plurality of interlocking insulation block ring segments where each segment comprises a containment form shell and insulating foam.
There is further within the scope of the invention, a method for providing ballast to an at least partially buried preformed chamber, comprising providing at least one ring formed of a plurality of interlocking ballast block ring segments; configuring each ring segment with at least one male interconnect and at least one female interconnect, each female interconnect being configured to receive a corresponding male interconnect, each ring segment comprising a containment form shell and cast mass; and securing each female interconnect to the corresponding male interconnect with corrosion resistant locking pins. The method further comprising providing a placement handle with a removable ring received in a lifting bolt disposed within the cast mass, and disposing a conforming profile about an internal circumference of the at least one ring conforming to a sidewall of the preformed chamber. Casting material may be introduced into the containment form through an aperture in a top wall of the containment form.
The foregoing description of the embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of this disclosure. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto.
This application claims the benefit of U.S. Provisional Application No. 61/334,800, filed May 14, 2010. That application is herein incorporated by reference in its entirety for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| 61334800 | May 2010 | US |
