AU622718B2 - Cast-in-place manhole liner apparatus and method - Google Patents

Description

g~~ 4 OPI DATE 02/04/90 AOJP DATE 10/05/90 APPLN. ID 43093 89 Per PCT NUMBER PCT/US89/03720 INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (51) International Patent Classification 4: t io 1 ublicat on !ber WO 90/02847 E02D 29/12, E03F 5/02 Al B28B 7/26 io bl on Da 22 March 1990 (22.03.90) (21) International Application Number: PCT/US89/03720 (81) Designated States: AT (European patent), AU, BE (European patent), CH (European patent), DE (European pa- (22) International Filing Date: 25 August 1989 (25.08.89) tent), DK, FI, FR (European patent), GB (European patent), IT (European patent), JP, LU (European patent), NL (European patent), NO, SE (European patent).

Priority data: 240,073 2 September 1988 (02.09.88) US Published With international search report.

(71) Applicant: ACTION PRODUCTS MARKETING COR- PORATION [US/US]; 6843 N.W. Trail Ridge, Johnston, IA 50131 (US).

(72)Inventor: TRIMBLE, Carroll, 0. 4403 Bogey Drive, Springdale, AR 72764 (US).

(74) Agents: VOORHEES, Michael, G. et al.; Zarley, McKee, Thomte, Voorhees Sease, 2400 Ruan Center, Des Moines, IA 50309 (US).

(54)Title: CAST-IN-PLACE MANHOLE LINER APPARATUS AND METHOD (57) Abstract Concrete liners are cast in manholes using a form structure (11) made up of a collection of sheet-metal, flanged, arcuate panels (13, 19). The panels (13, 19) are assembled in belts of generally circular cross-section commencing from the bot- 'i tom of the manhole for casting a concrete liner with a minimum thickness of about three inches and including openings created by sectional cylindrical inserts (83, 85, 89), all of which can be assembled, then disassembled after the concrete liner 11!' has set. To accommodate different shapes of manholes the II 9 panels can be formed into right conical, offset conical, and wedge-shaped (31, 33) belts to make transitions between verti- /19 cal and tilted sections of the manhole. A key panel (15, 16, 17) is provided to allow easy disassembly of the respective belts, each key panel including a relatively narrow portion (16) with vertical flanges forming an angle which diverges toward the center of the form structure.

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6 2 86- i I I tO 90/02847 PCT/US89/03720

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CAST-IN-PLACE MANHOLE LINER APPARATUS AND METHOD The present invention relates to a method and apparatus for casting concrete liners in existing, deteriorated manholes so that they will have many years of useful, substantially maintenance-free life.

Pre-cast concrete manhole walls have been known for many years including some such manhole construction methods for casting poured concrete walls for new manholes in place, as shown and described, for example, in Patent No. 3,729,165 granted April 24, 1973 to Carroll 0. Trimble (Cl. 249/144).

Forms for poured concrete manholes typically include steel shell outer forms and steel shell inner forms, both of which are designed to be disassembled and reused. Inner forms originally designed for new poured concrete manholes have also been used by themselves to cast concrete liners for the renewal of old, existing manholes, but the forms and methods used for producing new cast-in-place manholes in many instances are not adaptable for casting liners in existing, deteriorating manholes.

While there is an overall similarity in manhole configurations attributable to the common purpose of giving access to sewer lines, the variety found in manhole configurations over the last fifty to one hundred years is great, and previously known forms and poured concrete construction methods are inadaptable to a substantial percentage of manholes which are in need of renewal. The method and apparatus according to the present invention, on the other hand, provides an adaptable system by which nearly all manholes requiring renewal, including those with non-standard, odd configurations, may be provided with complete and effective poured concrete liners. Since the alternative to renewing manholes with a poured concrete liners. Since the alternative WO 90/02847 PCT/US89/03720 2 to renewing manholes with a poured concrete liner is removal of the manhole and replacement with a new manhole of poured concrete or other construction, and since this may frequently involve removal and replacement of poured concrete road surfaces or other structures, the economy of effort and savings produced by the present invention are very substantial.

Previous methods and apparatus for pouring concrete manholes, or liners therefor are exemplified by several prior patents. A very early form of poured concrete manhole is shown in Patent No.

992,782 granted May 23, 1911 to C. S. Lambie. The Lambie apparatus comprises internal forms consisting of downwardly flaring sections of annular shells "with the diameter of each corresponding to those above and below the same". The resulting poured concrete manhole then has a continuously flaring wall from the top to the bottom (although some portions may have a greater angle of flare than others).

Lambie makes no provision for removing the internal forms other than allowing the bottom section of forms to drop down after being disconnected and each upwardly adjacent section to be removed successively in a similar manner. Thus the Lambie arrangement would be quite inappropriate to meet the requirement to which the present invention is directed, namely the lining of existing manholes which may have a downward flaring, a non-flaring, or even an upward flaring configuration in parts.

Patent No. 4,127,990, granted December 5, 1978, to Otis L. Morrow (Cl. 405,36), shows a method for casting poured concrete manholes, but does not specify details of the apparatus which, presumably, would come from other prior art. The method is -3adaptable to new construction rather than renewal of existing manholes.

While the above-mentioned patent to Trimnble No., 3,729,165 shows forms for poured concrete manholes/which may be adapted to casting liners in existing manholes in a rudimentary manner in a limited number of cases, the forms shown in the 3,729,165 patent are inadequate for casting liners in many forms of manholes encountered.

According to a first aspect of the present invention there is provided a form system for casting new concrete walls within an existing manhole, said manhole having an open upper end and existing arcuate upstanding side walls, said manhole having a bottom wall, an inlet sewer pipe having an open end opening into said manhole adjacent said bottom wall and an outlet sewer pipe having San open end communicating within said manhole adjacent said bottom wall thereof, said form system comprising: a plurality of groups of at least three arcuate panels, each of said panels having upper and lower edges S 20 and opposite side edges, said upper, lower and side edges each having flanges formed thereon, each of said panels having an inner arcuate surface and an outer arcuate surface; first connecting means detachably interconnecting 25 said flanges of said side edges of said panels of each of said groups into a ring wherein said upper edges of said panels combine to form a circular upper edge of said ring and said lower edges of said panels combine to form a circular lower edge of said ring, said ring having an outer arcuate surface facing and spaced radially inwardly from said existing side walls of said manhole; second connecting means connecting said flanges of said upper edges of said panels in each of said rings to said flanges of said lower edges of said panels in one of said rings positioned thereabove so as to vertically stack said rings above one another so that said outwardly presented surfaces of said rings combine to create a 920205,gnsp.015,43093.spC,3 r 7 i if -3aliner form having a radially outwardly presented arcuate liner wall spaced radially inwardly from said existing manhole side wall, thereby creating an annular space therebetween, said liner form having an interior space, a lower liner form edge adjacent said bottom wall of said existing manhole and an upper liner form edge adjacent said upper edge of said manhole; a first insert form extending from said open inlet end of said inlet sewer pipe to said liner form and providing a conduit extending from said open inlet end of said inlet sewer pipe to said interior space of said liner form; a second insert form extending from said open outlet end of said outlet sewer pipe to said liner form and providing a conduit extending from said open outle sewer pipe to said interior space of said liner form whereby o• fluid can flow from said inlet end of said sewer pipe through said first insert to said interior space of said liner form and then through said second insert to said outlet sewer pipe; said first and second insert forms sealing said conduits thereof from said annular space between said liner form and said existing manhole walls so as to 25 prevent freshly poured concrete within said annular space from entering and blocking said conduits of said first and second inserts.

According to a second aspect of the present invention there is provided a method for casting new concrete walls within an existing manhole, said manhole having an open upper end and existing arcuate upstanding side walls, said manhole having a bottom wall, an inlet sewer pipe having an open end communicating within said manhole adjacent said bottom wall and an outlet sewer pipe having an open end communicating within said manhole adjacent said bottom wall thereof, said method 920205,gjnspe.015,43093.spe,4 -3bcomprising: assembling a first group of at least three rigid arcuate panels together into a ring within said manhole adjacent said bottom wall thereof, said ring having an annular upper edge and an annular lower edge, and an arcuate outer surface facing radially outwardly and being spaced radially inwardly from said side walls of said manhole so as to create an annular space therebetween, and an arcuate inner surface defining an interior space within said first ring; taking a first insert form having first and second opposite ends and a conduit extending therebetween; placing said first insert form within said manhole with said first end of said first insert form in i communication with said open end of said inlet sewer pipe, with said second end of said first insert form in communication with said interior space within said first ring, and with said conduit of said first insert form spanning said annular space between said first ring and said side walls of said manhole; taking a second insert form having first and second opposite ends and a conduit extending therebetween; S. placing said second insert form within said manhole 25 with said first end of said second insert form in communication with said open end of said outlet sewer pipe, with said second end of said second insert form in communication with said interior space within said first ring, and with said conduit of said second insert form spanning said annular space between said first ring and said side walls of said manhole; assembling a plurality of additional rings from groups of at least three of said arcuate panels; connecting said additional rings and said first ring together in vertically stacked relation to one another so as to create a liner form within said manhole which forms a continuation of said outer arcuate surface of said 920205,gjnspe.015,43093.spe,5 rW -3cfirst ring and which forms a continuation of said annular space between said outer arcuate surface of said first ring and said side wall of said manhole; filling said annular space between said liner form and said side wall of said manhole with freshly poured concrete whereby said first and second insert forms are surrounded by concrete and protect said conduits therein from said concrete and protect said conduits therein from said concrete so as to permit continuous flow of fluid from said inlet pipe into said manhole and thence outwardly from said manhole into said outlet pipe; permitting said concrete to cure and harden; disassembling said arcuate panels from one another; and removing said arcuate panels from said manhole.

The method and apparatus according to the present o• invention preferably includes features for dealing with oe the problem of lining manholes of unusual configuration 20 including wedge sections for dealing with slanted manhole portions, eccentric or skewed reducers for manhole offsets, methods and apparatus for bottom configurations without conventional benches for supporting the form S• structure and combinations of such problems. Also the apparatus according to the invention preferably includes improved key-panel construction which is generally included in each filler belt or reducer greatly facilitating rapid removal of the forms either from the top down or the bottom up. One feature of a preferred embodiment of the invention is that the lining process can be carried out completely without interfering with normal flow through the manhole. Normal flow is ensured in part by provision of inserts or other forms for producing an opening in the manhole liner communicating with the inlet or outlet openings in the manhole.

Prior provisions for producing an opening in the wall of a poured concrete manhole as shown in United 920205,gjnspe.0 5,43093.spe,6 -3d- States Patent No. 4,261,541 to Otis L. Morrow, granted April 4, 1981 (Cl. 249/10), have not been intended to be adaptable, and would not be adaptable, to permitting unimpeded flow through the manhole *e 920205,gjnspe.0 15,43093.spe,7 WO 90/02847 PCT/US89/03720 4 while a liner was cast in place. The/Mbrrow Apparatus is intended for and is only suitable for new manhole construction where the sewer pipe would be installed after the manhole wall was cast with an opening to accommodate the sewer pipe.

In addition to providing the features and o. fpreferreA advantages discussed above it is aalobject of the present invention to provide a method and apparatus for casting poured concrete liners in existing manholes which will be impervious to the influx of surface water or ground water and restore structural integrity to the manhole without taking the manhole or the sewer lines involved out of service.

p Pef-rre.

It is anotherkobject of the present invention to provide a method and apparatus for casting poured concrete liners in existing manholes which are adaptable to manhole configurations with various combinations of conical and cylindrical sections with vertical or non-vertical axes with a wide range of diameters., p. It is yet another object of the present invention to provide a method and apparatus for casting poured concrete liners in existing manholes with multiple inlet lines at the bottom or above the bottom of the manhole.

It is a further object of the present invention to provide methods and apparatus for casting poured concrete liners in existing manholes which are able to accommodate manholes with non-vertical portions or eccentric conical portions needed to avoid surface structures. It is still furtherkobject of the present invention'to provide a method and apparatus for casting poured concrete liners in existing manholes which accommodate manholes where the main sewer line 1 WO 90/02847 PCT/US89/03720 is off-center in the manhole or partly outside the periphery of the manhole.

Other objects and advantages of the invention will be apparent from consideration of the following description in conjunction with the appended drawings in which; FIGURE 1 is a perspective view (partially broken e- m boA><%r\t 04:" away) showing a form configuration according t o t he invention for casting a poured concrete liner in a non-standard manhole with non-vertical portions; FIGURE 2 is an enlarged fragmentary vertical.

sectional view showing an insert for forming an outlet hole in the bottom of a manhole liner; FIGURE 3 is a horizontal sectional view of the apparatus of FIGURE 2; FIGURE 4 is a top plan view of a group of filler panels including a key-panel to facilitate disassembly thereof; FIGURE 5 is a vertical sectional view of a reducer form including a key-panel and other panels; FIGURE 6 is a fragmentary bottom plan view of the apparatus of FIGURE FIGURE 7 is a perspective view of a wedge filler form; FIGURE 8 is a fragmentary enlarged sectional view showing the relation of a form as in FIGURE 1 to an existing manhole cover; FIGURE 9 is a perspective view of a group of filler panels and a canopy form as alternative means for creating bottom openings in a manhole liner; FIGURE 10 is a sectional view of an alternative form of insert comparable to that shown in FIGURES 2 and 3; FIGURE 11 is a side elevational view of the apparatus of FIGURE r DrCT/1 irE90Q/n'79 WO 90/02847 i, v..

FIGURE 12 is a sectional view of an alternative form of key-panel comparable to that shown in FIGURES 4, 5, or 6; FIGURE 13 is a perspective view showing a method and apparatus for pouring concrete into the cavity embocAeneW between the form structure according to the present invention and the pre-existing manhole wall; FIGURE 14 is a perspective view (partially broken away) illustrating a method and apparatus for raising filler forms after part of the concrete liner has been poured; FIGURE 15 is a side elevational view of a form structure according toLthe invention for an eccentric or offset manhole configuration; FIGURE 16 is a side elevational view illustrating the apparatus and process for lining a non-tapered manhole configuration; FIGURE 17 is a side elevational view of a form structure for an all-tapered manhole configuration; FIGURE 18 is a side elevational view of a form structure for a partially tapered manhole configuration; and FIGURE 19 is a side elevational view of a form structure for a manhole configuration with an untapered top portion and having a manhole cover ring embedded in the -liner.

Referring now to the drawings and particularly FIGURES 1, 2, and 3, a form structure 11 is shown assembled in a manhole in a manner to conform to the configuration of the walls 9 of the manhole.

The floor 7 of the manhole is typically provided with a trough 8 to channel the sewage from one or more inlet pipes to an outlet pipe. Frequently a manhole will be situated under pavement 5 of a parking lot, road, or the like as shown in FIGURE 1.

"q v I i ~ci* *0 90/02847 PCT/US89/03720 '7 A cover ring 3 is secured at the top of the manhole substantially flush with the pavement 5 and adapted to receive a manhole cover (not shown).

The form structure 11 is built up of various forms of arcuate sheet metal panels such as panel 13 in the form of a sector of a cylinder. Panels 13 are provided with peripheral flanges which serve to strengthen the panel and also as convenient means for fastening through-holes therein with bolts so that the panels may be connected to horizontally adjacent and vertically adjacent panels of similar or dissimilar form. Although panels such as 13 could be formed of rigid plastic or other material, sheet metal joined by welding is preferred.

A contractor or other entity involved in renewing manholes with poured concrete liners according to the present invention will be provided with a rather extensive set of panels for assembling a nearly unlimited variety of form configurations.

The nature of the forms provided can best be understood by reference to the following TABLE 1 which identifies the basic types of panels.

It will be noted that the form is built up with a succession of tiers or belts (hereinafter referred to as belts). The most common filler belts are made up of filler panels and a complete belt takes the form of a right circular cylinder. Typically each belt will be made up of four or six panels of the same height and subtending substantially equal angles. These panels are not identical, however, and, in particular, one such panel is divided into two parts and is referred to as the key-panel. One of the two parts of the key-panel has side flanges which are arranged at a small angle with respect to one another, such angle diverging toward the center WO 90/02847 PCT/US89/03720 WO 90/02847 of the form structure. Thus when the bolts or other fasteners holding this half of the key-panel in place are removed, it will readily slide inward to create an opening in that belt of panels after which the panels are no longer locked in place by their inwardly converging side flanges and may readily be removed.

In FIGURE 1 the key-panel 15 of the bottom-most belt is formed of two portions 16 and 17. Panel portion 16 has inwardly diverging side flanges. This bottom-most belt has three other panels, one panel 13 being shown, and another panel (like panel 13) not shown, plus a fourth panel opposite key-panel 15 (not shown). As shown in FIGURE 1 and FIGURE 4, key-panel has side flanges at its edges which are parallel to one another and the side flange of panel 13 which is adjacent to key-panel 15 is configured to fit keypanel 15. The same is true of the other panel which is adjacent to key-panel 15 on the other side.

All the other belts of panels in FIGURE 1 are shown with a different rotation and the key-panel which is present in these belts is not shown. For example, the belt third from the bottom shows a panel 19 and a panel 13, panel 19 being the panel opposite the key-panel for that belt. It will be noted that key-panel 19 has flanges which are radial or at right angles to the cylindrical surface and the flange at the adjoining edge of panel 13 is also radial. To aid workers in proper assembly of the panels they may be identified by diameter and also by single digit numbers identifying which one of the panels of a belt set is represented. For example, the panels of a four panel belt could be identified with key-panel as No. 1 and adjacent panels in a clockwise direction as No. 2, No. 3, and No. 4. The key-panel portions could be identified as 1-A and I-B if desired. i IVO 90/02847 PCT/US89/03720 Although the requirement for proper placement of different types of panels in a belt requires some care, it has the advantage that it is hard to mistakenly assemble a belt of panels without a keypanel. Clearly, omission of a key-panel in a belt would make the panels impossible to remove without destroying them once the concrete had been poured and set.

It is an important feature of the present method and apparatus for lining manholes that the sewer lines are maintained in service. In the situation illustrated in FIGURE 1, the installation of apparatus to accomplish this result is in part illustrated in FIGURES 2 and 3. As seen in FIGURES 2 and 3 trough 8 divides the floor 7 of the manhole into two parts (sometimes referred to as benches) and in many cases the form structure 11 may be set directly on the floor 7 of the manhole without impeding the flow through trough 8 and thus leaving the manhole and sewers operable during the lining process.

To provide an opening in the liner wall, a cylindrical insert formed of sections 83, 85, 83 and 89 is placed inside pipe 6 and abutting panel 13.

The sections 83, 85 and 89 are curved on one end to fit or substantially fit the arcuate surface of panel 13 which, in the case of FIGURE 1, has a diameter of 42 inches. The sections 83, 85 and 89 could be curved on the other end to fit a cylinder with the same or a different diameter. The sections 83, and 89 are configured in a manner similar to the previously described belt of panels 13, 15 and 19 at the bottom of the form structure 11 in FIGURE 1.

That is, at least one section 85 of the insert has two parts 86 and 87, the latter with inwardly 1 iili_ WO 90/02847 PC/US89/03720 0o converging flanges so that it can be readily taken out after the insert is used as a core in the poured concrete. This releases the other sections to be removed as well. Obviously, a permanent insert could be used as a core consisting of a single unitary cylinder which would not be removed.

Preferably one of the sections 83 has a bracket 82 secured thereto so that it and the other sections can be secured against panel 13 by a bolt 84 or other fastener. Bracket 82 may be provided with a slot rather than a circular hole to allow up and down adjustment of section 83 relative to panel 13. Also panel 13 may have more than one hole to accommodate a bolt 84 for further adjustability in positioning of section 83 and the other sections of the insert. It may be noted that small holes or apertures in the panels or between the panels a quarter of an inch or less do not permit passage of the concrete mixture and an assembled form structure need not be water tight. In disassembling a form structure after the concrete has been poured and set, the bolt or other fastener for 84 will be loosened to release panel 13 form the insert and after panel 13 has been removed, the sections 83, 86 and 89 of the insert will be disassembled to the extent necessary to remove them from the pipe 6 and from the concrete liner which has been poured around them.

In the case of sewer pipes which enter the manhole above the level of floor 7, a gate panel is provided having a gate 23 with an opening and a removable circular coverplate conforming to the outside diameter of a six or eight inch sewer pipe; the end of the sewer pipe extends through the opening of gate 23 in the panel 20 and the sewer pipe thus remains in service while the liner is being poured WO 90/02847 PCT/US89/03720 and, of course, afterward. Other sizes of gate openings may be provided as needed. If necessary, space between the outside of the sewer pipe and the edge of the gate opening may be caulked or grouted to prevent flow of concrete mix to the interior of the form structure 11.

The position of gate 23 may be conformed vertically to the position of the sewer by jacking the form structure 11 as will later be explained in detail. The belt of panels including panel 20 may be rotated to properly position gate 23 with respect to the sewer pipe and, if the desired position does not cause bolt holes to match up in the horizontal flanges, the flanges may be secured together by clamps rather than the usual bolts In a panel such as panel 13 subtending about the horizontal flanges may have bolt holes placed up to about 45" apart giving two bolt holes in each horizontal flange of panel 13. Obviously a greater number of bolts may be provided as shown or a variety of other bolt hole configurations could be adopted if desired.

As it will be seen in FIGURE 1, a number of belts formed of panels 13 and 19 (and also key-panels not shown) provide groups of filler panels of 42 inch diameter extending upwardly in the manhole.

Also shown are wedge panels 31 and 33 which serve to provide a tilt in the form structure 11 to conform to the configuration of the manhole walls 9.

A detail of wedge panels 31 and 33 is best shown in FIGURE 7 where it will be seen that two each of panels 31 and 33 are connected together to form a generally wedge-shaped belt. Preferably panels 33 are shaped to serve as right side or left side panels by inverting them, and the same is true of panels 31.

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WO 90/02847 PCr/US89/03720 12.

Panels 33 are preferably somewhat less than 90° in angular measure leaving about two to four inches gap in the circumference of the belt. This portion of the panels would be very thin and is not necessary to provide an adequately tight structure to hold the concrete mix. Due to the gap in the circumference of the wedge-shaped belt formed by panels 31 and 33 there is no need for a key-panel since either of the panels 33 can be removed to release panels 31. Wedge panels of two inch height may be only three in number with a gap of about It will be noted that there are two wedge-shaped belts of panels 31 and 33 if FIGURE 1. The lower one of the wedge-shaped belts causes a tilt for two filler belts and the upper wedge-shaped belt causes the axis of the form structure to be restored to vertical for those belts above.

As the diameter of the manhole walls 9 reduces near the top of the manhole, reducer panels 41, 43, and 47 (and two other panels not shown) form a reducer belt to reduce the form structure diameter from 42 inches to 36 inches.

A further belt formed of panels 51, 53, 55 and 57 and two other panels reduces the diameter of the form structure from 36 inches to 30 inches. The next belt is a filler belt of 30 inch diameter but only eight inches high and is formed of panels 79 and 73 and two other panels. At the top of the form structure is a group of panels 61, 63, 65 and 67 and two other panels not shown reducing the diameter of the form structure from 30 inches to 26 inches.

In some instances, a still small reducer for reducing the diameter from 26 inches to 20 inches will be useful. Such a reducer is illustrated in FIGURES 5 and 6. As noted in TABLE 1, the small

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i WO 90/02847 PCT/US89/03720 )3 reducer has only four panels (91, 95, 93 and one not shown in FIGURE 5) per belt rather than six panels as is the case with the larger reducers, otherwise it is typical.

Panel 95 is the key-panel formed of two panel portions 96 and 97 and adjacent to it on either side are panels 91 and 93 which differ only in being lefthanded and right-handed mirror images. A fourth panel not shown subtends about 90" of the conical form and has radial side flanges similar to the cylindrical panel 19 of FIGURE 4.

As best seen in FIGURE 5, side flanges 101 and 103 of panel 95 have junctions with top flanges which are parallel lines. The junctions of side flanges 101 and 103 with bottom flanges 90 are also parallel lines. Since flanges 101 and 103, if set perpendicular to the surface of the cone, would have an angle in the horizontal of about 90", this ieans that each flange 101 and 103 is set at an angle of about 45* with the surface of the cone. Flange 102 of panel 91 and flange 104 of panel 93 are also set at an angle of about 45" with the surface of the cone so that they fit flush with flanges 101 and 103, respectively. This angular orientation for flanges 101, 102, 103 and 104 is somewhat arbitrary and is subject to variation.

The two portions 96 and 97 are provided with flanges 107 and 105, respectively, so that the two portions 96 and 97 may be assembled and disassembled as are the panels of a group of panels. It will be seen that the junction of flange 105 of panel 97 with top flanges 90 or bottom flange 90 is not parallel to the corresponding junction of flange 103 with top flange 90 or bottom flange 90. Rather flange 105 is tilted at an angle with respect to flange 103 such 4- WO 90/02847 PCT/US89/03720 I l that the angle is diverging toward the center of the reducer.

Flange 107 of panel 96 has a corresponding tilt to mate with flange 105. Thus when the bolts or other connectors connecting flange 105 to flange 107 and flange 103 to flange 104 are removed, as well a any bolts through flanges 90, panel portion 97 is readily moved inward to break the circle of panels.

Thereafter panel portion 96 may readily be removed and all the other panels of the group or belt disassembled.

The angle of flanges 105 and 107 relative to the surface of the cone is shown as about 45" and while this is a satisfactory angle it is not necessary that the tilt angle be that great and it may be in some cases as low as 5. It will be understood that the fluid pressure of the liquid concrete mix tends to set up a compressive force clamping together the vertical (or near vertical) edges of the panels and the tilt of flanges 105 and 107 permits the release of the clamping force by inward movement of panel 97.

after the concrete is poured and set only inward movement is possible.

FIGURE 8 is a sectional view of the top portion of the form structure 11 showing how it is positioned in the top of the manhole. FIGURE 8 shows the arrangement before the concrete is poured to form the liner. Any conveniently available wood blocks 100 (or bricks) may be utilized to temporarily hold the form structure 11 in place when pouring is commenced so that the axis of the liner will be centered relative to the manhole cover rim 3. Blocks 100 will normally be removed after about two-thirds of the liner is poured to facilitate finishing the liner to near the top of panels 65 and 67 and the top of the form structure 11.

WO 90/02847 PCT/US89/03720 FIGURE 9 shows alternative means for forming a hole in the poured concrete liner at the location of an inlet or outlet sewer pipe. Flexible sheet metal canopy 111 is three to four inches in width and bridges the distance between panel 13, for example, and the wall of the manhole. Its inside edge is curved to conform to the contour of panel 63 as was the case of the sectional insert shown in FIGURES 2 and 3 and the outer edge of canopy 111 is preferably curved to conform to the manhole wall curvature.

Canopy 111 is provided with a bracket 113 and is secured to panel 13 with a bolt 115 or other fastener.

Also in FIGURE 9, panel 120 is provided with a gate 23 including a removable circular cover plate which may be about nine inches in diameter. Cover plate and panel 120 are provided with sheet metal tabs 25'by means of which the gate 23 is bolted or otherwise in panel 120 when no opening is desired. A small circular cut-out 27 may also be provided in gate 23 with additional tabs 29 for removably securing it in place. Thus the entire gate 23 is removed when a large opening for eight inch pipe) is desired and only the central cut-out 27 is removed when a smaller opening for six inch pipe) is desired. The arrangement of FIGURE 9 would provide for an inlet sewer pipe which was only slightly displaced above the floor of the manhole and an outlet sewer pipe which was partially below the floor of the manhole.

Another form of insert to maintain a sewer pipe opening in the liner is shown in FIGURES 10 and 11.

Sewer pipe 6 has inserted therein an insert comprising sections 183, 189, 183, 186 and 187 which are disassembled after the concrete is poured by WO 90/02847 PCT/US89/03720 first removing section 187 to break the circle and thereafter removing the other sections of the insert.

The apparatus of FIGURE 10 differs from that shown in FIGURES 1, 2 and 3 in that the bracket 182 is inside the insert and is provided with a number of holes for adjustable positioning of the insert relative to panel 13. It will be noted that an opening should always remain between the bottom of panel 13 and the bottom of insert section 183 to allow continued liquid flow in the course of the forming and pouring operation.

FIGURE 12 shows an alternative form of key-panel in which the two portions of key-panel 115 are quite unequal in width with portion 116 only about a quarter of the width of portion 117. Portion 116 is the removable portion having diverging side flanges 118 and 119. It may be noted that due to the small width of panel 116 flange 119 is almost at a right angle to the surface of panel 115, yet there is ample divergence of flanges 119 and 118 toward the center of the cylinder.

Outer edge flanges 118 of panel 115 are illustrated as being parallel as in key-panels previously described. Thus the key-panel 117 illustrated in FIGURE 12 is compatible with the previously described structure. It should be further noted, however, that there is no requirement that a system of forms according to the invention should have key-panels with parallel vertical edge flanges 118 as illustrated. In fact, flanges 118 and the adjacent flanges on panels 113 could be radial when the unbalanced key-panel 115 is utilized. Thus, an arrangement wherein all panels including the keypanel had radial edge flanges flanges at 900 to the surface of the cylinder cone or other surface of 2'-4 K I SWO 90/02847 PCT/US89/03720 )'7 revolution represented by the assembled panels) is within the scope of the invention.

FIGURE 13 illustrates accessory apparatus useful in pouring the concrete to form the liner with the method of the present invention including a funnel 131 to be attached to the end of a concrete mix delivery vehicle chute. Funnel 131 feeds into a tube 133 of sheet metal or the like which in turn feeds a flexible fabric hose 135 serving to deliver the flow of concrete mix to the space between form structure 11 and the manhole walls. A sheet metal shield 137 helps to keep concrete mix from spilling inside the form structure 11.

The process according to the invention starting from the beginning may be summarized as follows. The particular job having been examined and a source of concrete arranged, a suitably complete set of panels is brought to the site and assembly of the fbrm structure commences on the floor of the manhole by one workman. The manhole is considered a hazardous environment and the appropriate precautions dictated by professional standards and government regulations are followed. These will not be discussed at length, but include continual observation of the worker in the manhole, immediately available means to lift him from the manhole if necessary, provision of a high volume of fresh air to the bottom of the manhole and limitation of exposure to fumes to the maximum extent possible. Since the erection of the form structure proceeds very rapidly this enhances the safety of the operation. Also the fact that no workman need be present in the manhole when the concrete is actually poured represents an additional safety factor.

A belt of panels is assembled on the floor of the manhole which will allow a minimum three inch -i i j i 1~~ WO 90/02847 PCT/US89/03720 clearance between the liner form and the old manhole wall. At this point it is generally necessary to fill large openings between the bottom of the panels and the floor of the manhole with a grout consisting of a mortar or concrete mix or other suitable mixture. At the same time it is necessary to install the inserts which will create the channels in the liner for inlet and outlet sewer pipes. Openings around the inserts will also be filled with grout so that the space between the bottom belt of panels and the old manhole wall is substantially closed at the bottom. Additional belts of panels are assembled on top of the bottom belt with reducers or filler panels arranged to maintain about a minimum three inch clearance between the liner form and the old manhole wall. Thicknesses of the liner greater than three inches are not detrimental but they increase the amount of concrete required without any compensating advantage.

When the form structure has been completed to extend to or above the top of the manhole, the top panel belt is centered with blocks as illustrated in FIGURE 8 and the concrete mix may be poured from the delivery truck which is previously arranged for.

Preferably the concrete mix is three-quarter rock and is a conventional wall and foundation concrete mix except that it has greater amount of water to provide a wet mix that is easy to vibrate.

Two or three times in the course of the pouring operating the concrete is vibrated by rapping on the inside of the form with a light hammer or other tool.

Mechanical vibrators that are inserted in a concrete mix are not necessary and are not customarily used.

After the concrete has set for one to three hours it is sufficiently firm to remove the form oi- WO 90/02847 PCT/US89/03720 structure, and it is desirable to proceed on such a schedule.

Removal of the panels can proceed from the top or the bottom with successive belts of panels being dismantled by removing first the removable portion of the key-panel. Thereafter the other portion of the key-panel and the other panels are removed for that belt. The same procedure is used with successive belts until the form structure is entirely removed.

It is necessary to disconnect those panels secured to inserts at the bottom of the manhole before removing them, and it is then necessary to break down the sections of the insert in a similar manner to remove them from the inside of the sewer pipes.

The form panels removed from inside the newly lined manhole may be returned to the collection of form panels which may then be delivered to the next job site. The process described above is then repeated for the next manhole liner installation.

FIGURE 14 illustrates the method of adjusting the height of the form structure 11 for the purpose of aligning key-panels 20 with drop pipe inlets in the manhole, for adjusting the top of the form structure 11 to be flush with a wide manhole ceiling (as will be described with reference to FIGURE 16), or for some other purpose.

The liner installation process begins as described above, except that only the lower one or two belts of panels are assembled in the beginning and only a small quantity of concrete mix is used to form the bottom of the liner. Inserts are set and grout is used to fill gaps all as described above.

When the concrete 127 has acquired sufficient consistency to retain its shape, the bottom panels, such as 13, 15, 19 and other panels not shown, are jt- WO 90/02847 PCT/US89/03720 raised by a conventional hydraulic jack 125 or the like together with at least one other such jack (not shown) to achieve the desired vertical position of the form structure 11 when necessary (in many cases this step is not necessary). Blocks 128 are put in place to stabilize the form structure as required.

Panels are secured in place to construct the remaining portion of the form structure 11 as illustrated An FIURE 1 or in any of the following figures. Alternatively, the form structure may be assembled in part while the concrete 127 forming the base of the liner is setting. After the form structure is complete in its desired vertical position, the pouring of the concrete liner proceeds as described above, and the liner rests on the base formed by concrete 127. In FIGURE 14 the inserts forming openings in the concrete 127 have been removed prior to the final pouring operation, but that step may be deferred until the entire form structure 11 is disassembled. Specific examples of application of this method will be seen hereinafter in FIGURES 16 and 17.

In some cases the sewage passage from inlet to outlet may be partly outside the periphery of the manhole requiring a large opening in a side wall for access. To preserve such an opening in the liner it may be desirable to omit one or more panels In the bottom belt of panels and seal off the vertical gap where the panel is omitted with a plywood or sheet metal rectangle. Similarly the horizontal gap in the superjacent belt will be closed with an arcuate sheet of metal or plywood as a floor.

The overhanging panel or panels and the floor provided are supported with jacks from below or cables form above while two or three panel heights of WVO 90/02847 PCT/US89/03720 21 liner are poured and allowed to set. Thereafter the support is unnecessary and the form structure may be completed and the liner poured to complete the installation.

FIGURE 15 shows a form structure 415 for creating a liner in a manhole with walls 109 which are offset sot hat the top of the manhole is eccentric with respect to the bottom of the manhole.

after pouring a liner base of concrete 127, form structure 415 has been raised by a jack 125 and blocked with blocks 128 as previously described with reference to FIGURE 14.

The bottom three belts of form structure 415 are shown for illustration as 42 inches in diameter and formed by panels 13, 19, 20 and other panels not shown. A sewer pipe inlet 24 is elevated above the floor 7 of the manhole and is accommodated by gate panel 20 having gate opening 23 due to the adjustment of the form structure vertical position.

An offset reducer with diameters of 42 inches and 36 inches is formed by panels 157, 155, 153, 151 and other panels not shown, and a further offset reducer with diameters of 36 inches and 26 inches is formed by panels 147, 145, 153, 141 and other panels not shown. Topping out the form structure 415 is a common reducer with diameters of 26 inches and inches formed of panels 91 and 99 and other panels not shown. The cavity between form structure 415 and manhole walls 109 is ready to be poured with concrete mix after which the panels of the structure would be disassembled in accordance with the method previously described.

FIGURE 16 shows a wide, flat top manhole with walls 109, a reinforced concrete top 505, and a manhole ring casting 3. the form structure 416 for WO 90/02847 PCT/US89/03720 WO 90/02847 lining this manhole includes panels 219, 213 and other panels not shown, yielding a liner for structure 416 of 48 inch diameter, for example. As previously described, jacks 125 have been employed to raise the form structure 416 to the desired vertical position after a liner base of concrete 127 has been poured as described with reference to previous embodiments.

At least one opening 201 is cut in the top 505 of the manhole to permit concrete mix to be poured between the form structure 416 and the walls 109 filling the cavity therebetween completely to the top leaving no gap between the top of the liner and the top 505 of the manhole. This is possible because the form structure 416 has been jacked up to be flush with the top 505 of the manhole. Any gaps which are large enough to be a problem may be caulked to adequately seal this junction. Pipe inserts 516 similar to the type previously illustrated or in other forms are used to produce an opening through the liner from sewer pipe 6 to the interior of the manhole. Except for creating the opening 201 in the top 505 of the manhole and filling it on completion of the liner, the method of operation for FIGURE 16 is essentially as previously described.

FIGURE 17 shows a form structure 417 for a manhole with conical walls 9. A manhole of this type and certain of the other manholes may be in part above ground, but this does not materially affect the process of installing a liner. The form structure 417 of FIGURE 17 tapers from 48 inches at the bottom to 20 inches at the top and from the bottom up is formed of panels 161, 163, 169, 41, 43, 49, 51, 53, 59, 61, 63, 69, 91, 99 and other panels not shown. The basic method of producing a liner would be used r^; WO 90/02847 PCT/US89/03720 23 in conjunction with form structure 417 as previously described.

The basic method of casting a liner would also be used in respect to the manhole illustrated in FIGURE 18 absent any elevated inlet sewer pipes or other complications. The form structure 418 for FIGURE 18 is made up of 42 inch diameter panels 13 and 19 and other panels not shown together with reducer panels 41, 43, 49, 51, 53, 59 and others not shown to reduce the diameter from 42 to 36 to inches. The use of half-height panels is illustrated in the 30 inch diameter belt including panels 179 and 173 and other panels not shown. The belt including panels 61, 63 and 69 reduces the diameter from inches to 26 inches above which is a cylindrical belt of 26 inch diameter including panels 223 and 229 and another panel. The form structure 418 is topped by the previously described reducer of 26 and 20 inches diameter including panels 91, 99 and two other panels.

The process of installing the liner using the apparatus illustrated in FIGURE 18 would in general be the same as that previously described for FIGURE 17 and previous figures.

FIGURE 19 shows a form structure 419 set up to permit a manhole liner to be poured flush with the street and the top of a manhole cover rim 3. The form structure 419 of FIGURE 19 includes a reducer of 42 and 36 inch diameters including panels 41, 43, 49 and others not shown; a filler panel group including panels 313 and 319 together with other panels not shown, and a reducer of 36 and 30 inches diameter including panels 51, 53, 59 and other panels not shown.

PMTUS9/0,172 3 WO 90/02847 PCT/US89/032 The top portion of the form structure 419 is formed of 30 inch diameter cylindrical panels 413, 419 and others not shown which are selected to be of appropriate size to be covered by the manhole cover ring 3 so that the cover ring 3 will be embedded in the concrete at the top of the liner which is finished off flush with the pavement 5. Except for this last step of embedding the cover ring 3 in the concrete at the top of the liner, the process for forming the liner in the situation illustrated in FIGURE 19 will be as previously described.

From the foregoing description, illustration and explanations it will be understood that apparatus and methods for forming liners to renew failing manhole wall structures or the like are provided by the present invention which restore the manholes to full effectiveness to prevent influx of ground water or rainwater in a deteriorating sewer system. With the apparatus and methods of the present invention this may be accomplished much more rapidly and at far less expense than would be involved in replacing, rebuilding, or repairing the existing manhole structures.

While numerous modifications and variations of the invention have been shown, described, or suggested above it will be apparent to those skilled in the art that other variations and modifications may be made within the scope of the invention and accordingly the scope of the invention is not to be considered limited to those embodiments shown or suggested, but is rather to be determined by reference to the appended claims.

4 4 1 4 WO 90/02847 PTU8/32 PCr/US89/03720 25 TABLE I Regular Sizes Common Reducers: Large D 48 42 36 26 Small D 42 36 30 26 20 Height 15 15 15 15 25 PCS /BELT 6 6 6 6 4 Eccentric Reducers: Fillers: Diamn.

48 42 36 26 Heights 15.8 15.8 15.8 12.6 12.6 0-2,0-4,0-8,0-15 0-2,0-4,0-8 0-2,0-4,0-8 PCS /BELT 4 4 4 4 3 Wedge Fillers: 4 (or 4 (or 4 (or in 2 "HT) in 2 "HT) in 2 "HT) Super Sizes Common Reducers: Large D 54 Small D 54 28 Height 30 30

PCS/BELT

Fillers: Diaxn.

54 Heights 30,15,8 30, 15,8 Pcs /BELT Ur -ru-rF- S 's-ri 4

Claims (6)

1. 2. A form system according to claim 1 wherein said first and second insert forms each comprise at least two arcuate members having inner and outer arcuate surface means detachably interconnecting said arcuate members so that said outer surfaces of said arcuate members combine to form a smooth solid arcuate surface generally in the shape of a cylinder, at least one of said arcuate members being formed into two separable parts with a dividing line generally parallel to the axis of said cylinder.
2. 3. A form system according to claim 2 wherein one of said parts includes opposite edge surfaces, one of which is along said dividing line and forms an angle of at least 3° with said one part's opposite edge surface, said angle diverging in the direction extending radially inwardly towards the cylindrical axis of said smooth arcuate surface.
3. 4. A form system according to claim 3 wherein each of said Se first and second insert forms each include an inner axial end matingly fitted against said outwardly presented arcuate liner wall, and securing means for securing said first and second insert forms to said outer arcuate liner wall with at a portion of said inner axial ends of said first and second insert forms extending below said lower liner form edge whereby fluid can flow from said first inlet form below said lower liner form edge into said interior space of said liner form and then below said lower liner form edge into said second inlet form. -28- I 0.. i _i A method for casting new concrete walls within an existing manhole, said manhole having an open upper end and existing arcuate upstanding side walls, said manhole having a bottom wall, an inlet sewer pipe having an open end communicating within said manhole adjacent said bottom wall and an outlet sewer pipe having an open end communicating within said manhole adjacent said bottom wall thereof, said method comprising: kssembling a first group of at least three rigid arcuate panels together into a ring within said manhole adjacent said bottom wall thereof, said ring having an annular upper edge i and an annular lower edge, and an arcuate outer surface facing radially outwardly and being spaced radially inwardly some from said side walls of said manhole so as to create an o• annular space therebetween, and an arcuate inner surface defining an interior space within said first ring; taking a first insert form having first and second opposite ends ice'el and a conduit extending therebetween; S placing said first insert form within said manhole with said first end of said first insert form in communication with said open end of said inlet sewer pipe, with said second end of said first insert form in communication with said interior space within said first ring, and with said conduit of said first insert form spanning said annular space between said first ring and said side walls of said manhole; -29- .4 ~p3 ,t 4 *5S* S S .r taking a second insert form having first and second opposite ends and a conduit extending therebetween; placing said second insert form within said manhole with said first end of said second insert form in communication with said open end of said outlet sewer pipe, with said second end of said second insert form in communication with said interior space within said first ring, and with said conduit of said second insert form spanning said annular space between said first ring and said side walls of said manhole; assembling a plurality of additional rings from groups of at least three of said arcuate panels; connecting said additional rings and said first ring together in vertically stacked relation to one another so as to create a liner form within said manhole which forms a continuation of said outer arcuate surface of said first ring and which forms a continuation of said annular space between said outer arcuate surface of said first ring and said side wall of said manhole; filling said annular space between said liner form and said side wall of said manhole with freshly poured concrete whereby said first and second insert forms are surrounded by concrete and protect said conduits therein from said concrete so as to permit continuous flow of fluid from said inlet pipe into said manhole and thence outwardly from said manhole into said outlet pipe; permitting said concrete to cure and harden; disassembling said arcuate panels from one another; and removing said arcuate panels from said manhole.
4. 6. A method according to claim 5 and further comprising making a first pour of uncured concrete into said annular space between said first ring and said manhole side wall before assembling said additional rings.
5. 7. A method according to claim 6 and further comprising permitting said first pour of concrete to cure and harden, and jacking said first ring upwardly within said manhole after said first pour of concrete has cured and hardened. e *9O9 8. 1* A form system substantially as hereinbefore described with reference to the accompanying drawings.
6. 9. A method for casting new concrete walls -9 substantially as hereinbefore described with reference to the accompanying drawings. DATED this 6th day of February 1992 Action Products Marketing Corporation By Its Patent Attorneys DAVIES COLLISON CAVE -31- 7" I sc