Structural manhole assembly

Abstract

A structural thermoplastic manhole assembly fits into gravity sanitary sewer service. The assembly includes a base having at least one inlet connection region, at least one outlet connection region, an interior hydraulically contoured flow path configured to direct wastewater by gravity toward the outlet connection region, and a plate beneath the base. A riser cylinder joins to the base such that the base and the riser cylinder define a substantially monolithic manhole body. The riser cylinder uses a solid-wall, profile-wall, or hollow-core wall polymeric cylinder. The assembly has construction from polyethylene or other thermoplastic materials, including polypropylene and polyvinyl chloride. The assembly comes from manufacturing using molding, extrusion, joining, or additive manufacturing processes. The base provides hydraulically contoured flow without hydraulic jumps and debris. The assembly also has a form upon the plate with radial gussets to the riser that receives concrete for ballast.

Description

[0001] STRUCTURAL MANHOLE ASSEMBLY

[0002] TECHNICAL FIELD

[0003] The structural manhole assembly generally relates to wastewater systems and manholes in particular.

[0004] BACKGROUND OF THE INVENTION

[0005] The present invention relates to wastewater systems in general, and manholes in particular.

[0006] Mankind uses and makes various substances in life and in business. Early on, mankind consumes water as a beverage and with meals. Potable water calls for its cleaning arid that uses large amounts of chlorine whether liquid or gaseous. Eventually, mankind digests its meals, and mankind’s industry then uses various products of wide description. Select products come from processing and refining many sources into desirable materials, such as polymers, e.g., polyvinyl chloride. Select materials have inherent hazards though seeing use by the railcar load and the truckload. Following mankind’s digestion and industry’s production, a sanitary society then calls for processing wastewater from that digestion and production. The wastewater with its dissolved solids, organic molecules, inorganic molecules, and a host of other substances, known and unknown, travel by gravity. The wastewater then reaches a processing plant that treats the wastewater to mandated standards for release into the environment. Such processing uses large amounts of bacterial agents, chelating agents, and chlorine.

[0007] The history of sanitary sewer collection systems dates back to ancient civilizations, with the Romans receiving credit for pioneering efficient sewer systems. The Roman sewer systems, including the famous Cloaca Maxima in Rome, utilized stone and day pipelines to transport

[0008] CM / Eifcana Early DN1879 PCT Pat App, 04 / 15 / 26 |wastewater away from populated areas. These systems relied on gravity to guide the flow of wastewater, using carefully calculated slopes in their construction. Roman engineers demonstrated remarkable skill in designing sewer networks that discharged wastewater into nearby water bodies, such as rivers. These systems laid the foundation for modern sanitary sewer systems, or wastewater systems.

[0009] Following the decline of the Roman Empire, advancements in sewer systems stagnated for centuries. During medieval times, waste disposal largely consisted of open ditches and cesspits, often readily contaminated and posed significant public health risks. Following the industrial revolution in the 19th century, sanitary sewer systems resumed evolving into more structured and efficient designs. This period introduced underground sewer networks made from brick and concrete. Cities, like London and Paris, spearheaded the development of modern sewer systems, motivated by the need to address urban sanitation and to combat outbreaks of diseases like cholera.

[0010] Modern sanitary sewer systems have a meticulous design to optimize wastewater collection and conveyance. The heart of these systems has the principle of gravity flow. Sewer pipes have their installations at calculated slopes to harness the power of gravity, ensuring the smooth transport of wastewater to a common discharge point, often a wastewater treatment facility. Straight line pipe installation has become a fundamental practice in modern sewer design, as it minimizes flow resistance and promotes efficient monitoring and maintenance. However, when changes in horizontal or vertical alignment become necessary, manhole structures have their installations at these junctions. Manholes provide access points for inspection, maintenance, and cleaning, thereby ensuring the longevity and reliability of the sewer system.

[0011] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 2Materials used in the construction of modern sewer systems have undergone significant evolution to meet the demands of harsh operating environments. Sewer pipes commonly have construction from durable materials such as reinforced concrete, PVC, and other polymers. Manhole structures, which are vital for system functionality, have their primary construction using precast concrete due to its strength and versatility. Despite its widespread use, concrete remains susceptible to corrosion and degradation caused by the corrosive liquids and gases present in wastewater. Hydrogen sulfide gas, a byproduct of anaerobic decomposition within sewer systems, has particular notoriety for its corrosive effects on concrete surfaces. Over time, concrete manholes experience premature wear and failure, necessitating costly repairs and replacements.

[0012] The challenges posed by corrosive environments have prompted the need for innovative solutions in modern sewer system design. The development of manhole structures as impervious to corrosion remains essential for ensuring the long term durability and efficiency of wastewater collection systems. By mitigating the common corrosion problems associated with concrete manholes, these advancements aim to reduce maintenance costs and extend the lifespan of sanitary sewer infrastructure.

[0013] Sanitary sewer systems have evolved from ancient Roman innovations to modern gravity based designs that rely on carefully engineered methodologies for wastewater collection and conveyance. These systems necessitate the strategic installation of sewer manhole structures to facilitate inspection and maintenance. Modern gravity based sanitary' sewer systems require the design and construction of manhole structures that meet several key criteria. These criteria include structures capable of rapid manufacturing, and preferably single piece construction. Additional criteria include watertight structures, which resist inflow and infiltration, and an anticipated lifecycle of 100 years or more. By addressing

[0014] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 3these requirements, modern sanitary sewer systems can achieve enhanced reliability, efficiency, and cost-effectiveness, while mitigating the challenges posed by harsh operating environments.

[0015] As described above, a wastewater system often follows terrain and has a downward slope, taking advantage of gravity to propel wastewater downhill. The wastewater system thus has an abundance of lines of pipes throughout the territory of the wastewater system. Following terrain with its downward slope, the lines then have installed junctions, grade changes, and azimuth changes among other impediments to straight line flow. At each junction or change, contents of wastewater may accumulate and if they clog, the wastewater may back up. Thus manholes have their placements at such junctions and changes so that a worker may enter and remove accumulated contents and otherwise repair the line. Alas, wastewater with its contents and dissolved molecules aggressively degrades existing concrete manholes, shortening their useful lives.

[0016] DESCRIPTION OF THE PRIOR ART

[0017] Industry, academia, government, plant operators, transportation lines and others have established various criteria for designing, building, operating, and decommissioning wastewater systems. Let us turn to some of them. Wastewater often comes from a wide area, often measured in square miles or acres, called a catchment or sewer shed. The wastewater though undergoes treatment at select plants. The wastewater goes from a catchment to a few defined points at the treatment plants. To accomplish that, sewer systems use pipes, typically concrete, cast iron, steel, terra cotta, or polymer, having a slope so that gravity makes the waste water flow. The slope follows the terrain and it vagaries. As suggested above, the vagaries of terrain along with distance prompt installation of manholes so a worker may inspect a sewer line from time to time.

[0018] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 4Currently, the prior art have various designs and constructions related to manholes and their alternate name of inverts. The patent to LaBenz, No. 4341236 describes a sewer manhole channel construction method. This method formed a channel in the bottom of a manhole using triangular and rectangular shaped elements.

[0019] LaBenz has a second patent, No. 4444221, also upon a sewer manhole channel construction method. This ‘221 patent has its channel 61 in the bottom of a manhole but just using triangular shaped elements.

[0020] The patent to Duran, No. 5553973, described flumes for manhole inverts. These flumes have an open cross section placed upon the bottom of a manhole and the embedded into concrete placed upon the bottom.

[0021] The patent to Dorsey, No. 4867411, showed a system to cast a manhole invert. It shows a mold system of components that assemble to form channels in a concrete invert.

[0022] Pat. Pub. No. 2004 / 0040221 to Airheart described a molded manhole unit. Airheart shows a molded inlet that has a manifold showing flow paths. Airheart’s unit also has dome shaped sides.

[0023] The German patent No. 102006038664 to Funke has a Structural Manhole Assembly. The base assembled with the pipes molded into a separate piece. This patent has a shell and a berm in its construction.

[0024] The Korean patent No. KR100673995 shows a method to make concrete inverts. This method makes a complete concrete invert without polymer molding. This patent also has the invert resting on the bottom of the manhole.

[0025] The next Korean patent No. KR100427437 describes an inverter construction frame of a manhole. This patent shows a bottom plate placed into a manhole and a rotating plate with flumes upon it.

[0026] Nicholas of the United Kingdon had a British patent GB1577986 for improvements related to inspection chamber. This patent describes a single

[0027] CM / Eikana Early DN1879 PCT Pat App, 04 / 15 / 26piece injection molded chamber. Here though, the base has a rim with a tongue to fit a groove in an extension above the base. This patent also has a removable obturating member.

[0028] And a European Patent Publication to Funke, No. EP0821111, shows a prefabricated concrete manhole element with a plastic liner, it has a concrete shaft with a liner on its top, and interior, but not its bottom. The plastic liner extends partially down the sidewall in the vicinity of an inlet or an outlet.

[0029] In this specification, the use of man generally, operator, worker, and the like implies people of all genders who work in industry with wastewater lines of all description.

[0030] The Structural Manhole Assembly overcomes the above-mentioned disadvantages and drawbacks of the prior art. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new and improved Structural Manhole Assembly which has all the advantages of the prior art mentioned heretofore and many novel features that result in Structural Manhole Assembly which are not anticipated, rendered obvious, suggested, or even implied by the prior art, either alone or in any combination thereof.

[0031] SUMMARY OF THE INVENTION

[0032] The Structural Manhole Assembly has a riser of varying height that welds to a base beneath its manhole cover and a plate that welds beneath the base to the riser. The base has a round form with an outlet and at least three inlets, preferably five inlets, which admit wastewater into the invention. A prime inlet has a coaxial alignment with the outlet. Two junior inlets enter the base perpendicular to the prime inlet. And two lesser inlets each enter the base between the prime inlet and one junior inlet. Each inlet opens to a concave throat and the throats open into swales that guide the

[0033] CM / Eifcana Early DN1879 PCT Pat App, 04 / 15 / 26wastewater to the outlet for discharge. The prime inlet, its throat, a throat to the outlet, and the outlet have a slope so wastewater flows under gravity. The inlets have a separation defined by curves that also shape the throats as they intersect into the swales for wastewater flow with a minimum of hydraulic jumps and accumulation of debris. The Assembly also has a form upon the plate with radial gussets to the riser that receives concrete for ballast.

[0034] There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated. The assembly also includes an upright polymer body joined to a hollow molded base having one or more inlet connections, an outlet connection, and a hydraulically contoured flow region that directs liquid by gravity toward the outlet. The base may have rotomblded construction and may include one or more openings or apertures for grout or other fill material into an internal chamber to increase weight, stiffness, or flotation resistance. The assembly may have a top plate joined to the riser and may include support gussets. The manhole assembly may be installed with anti-flotation and traffic-bearing support structures. Additional features of the invention will be described hereinafter, and which will form the subject matter of the claims attached.

[0035] Numerous objects, features and advantages of the present invention will be readily apparent to those of ordinary skill In the art upon a reading of the following detailed description of presently preferred, but nonetheless illustrative, embodiments of the present invention when taken in conjunction with the accompanying drawings. In this respect, before explaining the current embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or

[0036] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 7illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.

[0037] As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and devices for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and the scope of the present invention.

[0038] It is therefore an object of the present invention to provide a new and improved Structural Manhole Assembly that has a weighted base and a riser of a chosen height.

[0039] Still another object of the present invention is to provide a Structural Manhole Assembly that has use for large wastewater systems in urban and residential areas, industries, and processing plants.

[0040] Still another object of the present invention is to provide a Structural Manhole Assembly suitable for installation 7 meters, or 23 feet, below the ground surface.

[0041] Still another object of the present invention is to provide a Structural Manhole Assembly that has application in many industries such as residential construction, commercial construction, road building, oil production, fracking systems, chemical facilities, water-wastewater facilities, fertilizer facilities, food production, and operation of landfills including hazardous and non-hazardous.

[0042] Still another object of the present invention is to provide a Structural Manhole Assembly that has a slope for gravity drainage of wastewater through it, fit into an excavation in land.

[0043] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 gStill another object of the present invention is to provide a Structural Manhole Assembly that has a base used as deadload against hydrostatic forces.

[0044] Still another object of the present invention is to provide a Structural Manhole Assembly that has a riser, or other vertical structure, designed of a material to repel and resist hazardous material without compromising structural integrity.

[0045] Still another object of the present invention is to provide a Structural Manhole Assembly that helps the industrial, wastewater collection, and wastewater plant environments to avoid hazardous materials spills.

[0046] Still another object of the present invention is to provide a Structural Manhole Assembly that has faster construction time than existing methods.

[0047] Still another object of the present invention is to provide a Structural Manhole Assembly that has lower rates of personnel accidents during construction and later during operation.

[0048] Still another object of the present invention is to provide a Structural Manhole Assembly that prevents further leaks outside of it.

[0049] Still another object of the present invention is to provide a Structural Manhole Assembly that maintains its structural integrity during periods of low flow, high flow, a storm surge event, and a spill event

[0050] Still another object of the present invention is to provide a Structural Manhole Assembly that maintains its elevation in swampy ground and during a high water table event.

[0051] Still another object of the present invention is to provide a Structural Manhole Assembly that maintains its elevation using inert ballast.

[0052] Still another object of the present invention is to provide a Structural Manhole Assembly that is factory assembled as a single-piece structural unit prior to installation.

[0053] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 9Still another object of the present invention is to provide a Structural Manhole Assembly that has fill material to increase weight, stiffness, flotation resistance, and structural reinforcement of the assembly.

[0054] Still another object of the present invention is to provide a Structural Manhole Assembly that has one or more lifting lugs to ease field installation.

[0055] Still another object of the present invention is to provide a Structural Manhole Assembly that has an internal ladder placed for a user to access the interior space of the Assembly.

[0056] Still another object of the present invention is to provide a Structural Manhole Assembly that transfers pedestrian and vehicle traffic loading from its cover to and through its riser.

[0057] Still another object of the present invention is to provide a Structural Manhole Assembly that may be easily and efficiently utilized by the regulatory, design, construction, operation, and remediation sectors of the consuming industries.

[0058] These together with other objects of the invention, along with the various features of novelty that characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated preferred embodiments of the invention.

[0059] BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In referring to the drawings,

[0061] Fig. 1 is a perspective view of an alternate embodiment of the present invention;

[0062] Fig, 2 is a section view of the present invention;

[0063] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 ] (}Fig. 3 is a plan view of the base of the present invention;

[0064] Fig. 4 is a section view of the base of the present invention;

[0065] Fig. 5 is a perspective view of the base of the present invention; Fig. 6 is a bottom view of the base of the present invention;

[0066] Fig. 7 is a perspective view of the preferred embodiment of the present invention;

[0067] Fig. 8 is a section view of the present invention;

[0068] Fig. 9 is an exploded view of the present invention;

[0069] Fig. 10 is a section view of the present invention;

[0070] Fig. 11 is a plan view of the top of the present invention with gussets spaced away from the outlet; and

[0071] Fig. 12 is a plan view of the top of the present invention with gussets upon inlets and the outlet.

[0072] The same reference numerals refer to the same parts throughout the various figures.

[0073] DESCRIPTION OF THE PREFERRED EMBODIMENT

[0074] Referring now to the drawings, and particularly to Figs. 1-5, an alternate embodiment of the Structural Manhole Assembly of the present invention appears as shown in Fig. 1. There it shows a manhole of the invention as at 10 with a classic manhole cover M at the top before installation in the ground. Beneath the cover M, the invention has a polymer cylindrical riser 20 welded upon a polymer base, not shown, and upon a plate 21 typically of wider diameter than the riser, a junior inlet 32 into the riser 20, here shown towards the left, in communication with the base, and an outlet 34 out from the riser, here shown towards the right, exhausting communication from the base. The invention undergoes assembly in factory conditions and eventually arrives at a jobsite ready for installation. The riser generally has a continuous form without segments when it leaves the

[0075] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 ] |factory. The factory produces risers to varying lengths that meet the depth of each installation. Upon completion of assembly, the factory puts the invention through vacuum testing and certifies the Structural Manhole Assembly to pressure and other appropriate standards. The Structural Manhole Assembly leaves its factory as a single piece. The Structural Manhole Assembly has a design life of at least fifty years. The Structural Manhole Assembly, particularly its concrete filled chamber, prevents groundwater intrusion into the invention and resists hydrostatic pressures less than thickness of a base multiplied by density of concrete, approximately 50 psi. Though the invention utilizes a chamber, an alternate embodiment may use a cavity or internal cavity to receive ballast, filler, or concrete.

[0076] Fig. 2 shows the Structural Manhole Assembly in a section view along line 2-2 upon a plane coaxial with the outlet 34 and perpendicular to plate 21 and during usage wastewater flows from left to right in this figure from a prime inlet 31 to the outlet 34. The wastewater flows down a slope as later shown and described. Though this description mentions wastewater aplenty, the invention also allows passage of other fluids and slurries, collectively liquids.

[0077] The invention has the manhole cover M atop the riser 20 as before. The riser may have various heights to suit the plans and specifications of a job. The riser receives the prime inlet 31 here shown to the left and well below the cover M. The prime inlet opens into a base 30 here shown in section and later shown and described in detail in Figs. 3-6. The base 30 receives a junior inlet 32, here shown towards the center of the figure, and itself shown on end and thus open. The junior inlet shown extends from the base into the plane of the figure and on into the riser in the background. To the right of the figure and the base, the riser has the outlet 34. Beneath the base, the invention has its plate 21 that spans across the end of the riser

[0078] CM / Elkana Early DN1879 PCT Pat App, 0-4 / 15 / 26 } 7opposite the manhole cover M. The plate has a generally round shape as shown in Fig. 1 and a diameter greater than that of the riser. The riser connects to the plate with welding, either thermal or chemical, adhesives, cohesives, and with sealed mechanical connections, including clips, screws, and bolts.

[0079] Fig. 3 illustrates a plan view, or top view, of the base 30 generally seen within the riser as when the manhole cover attains an open position. The base has a round shape with five inlets. The inlets include the prime inlet 31 shown towards the left of the figure at a 9 o'clock position, denoting the high part of the base or uphill, and in line with the outlet 34, two opposite junior inlets 32 perpendicular to the prime inlet at the 6 o’clock and 12 o'clock positions, and two lesser inlets 33 oriented halfway between the prime inlet 31 and a junior inlet 32. Having introduced the outlet and the inlets of the invention, the Applicants note that the inlets and the outlet may take the form of pipe stubs configured for connection to nominal 8-inch piping for wastewater or otherwise. Moreover, the inlets and the outlet have a configuration to connect to SDR 26 pipe, SDR 35 pipe, or both. The two lesser inlets have their orientations at a forty five degree angle to the prime inlet. Each inlet has a neck 39 that receives a pipe, not shown, carrying wastewater into the Structural Manhole Assembly. The neck has a slightly larger diameter than the radius of any inlet. The five inlets have a radial orientation and channelize wastewater flow into the outlet with a minimum of hydraulic jumps and of turbulence across the base. The prime inlet opens to a first throat 35, then has a first curve 41 before each lesser inlet 33. Each lesser inlet 33 opens to a third throat 37 that then has a third curve 43 to each junior inlet 32 that opens to a second throat 36. Each second throat 36 then has a second curve 45 that extends to a fourth throat 38 that exhausts through the outlet O. Each lesser inlet 33 opens to a third swale 46 in the interior of the base, each junior 32 inlet opens to a second swale

[0080] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 ]45 downstope from the third swale 46, and a first swale 44 passes between the other swales 45, 46 along a flow path of the wastewater to the outlet 34 on the right of the figure at the 3 o’clock position. The inlets 31, 32, 33 and the outlet 34 range from 4 inch to 12 inch in diameter. Select inlets have an SDR 26 rating where SDR means Standard Dimension Ratio. The first throat 35, second throats 36, third throats 37, and fourth throat 38 have rounded concave shapes interrupted by the first curves 41, the second curves 42, and the third curves 43. The three curves 41, 42, 43 form the shapes of the base between the prime inlet 31 and the two lesser inlets 33, the two junior inlets 32 and the outlet 34, and the two lesser inlets 33 and the two junior inlets 32, respectively. The three curves 41, 42, 43 also share a common plane when closest to an inlet. The first throat, second throats, and third throats have the first curve, second curve, and the third curve interrupting them and creating a first swale 44, a second swale 45, and a third swale 46. Each swale has a partial concave form representing a portion of the throats that intersect at the wide portion of each swale. The first swale 44 has an approximate double arrowhead shape between the rounded first through 35 and the fourth throat 38. The first swale becomes the bottom of all of the swale discharging wastewater towards the fourth throat 38 and down to the outlet 34. The swales descend from the common plane of the curves to the bottom of the fourth throat as shown next in Fig.

[0081] 4.

[0082] Fig. 4 describes a section view, along line 4-4, through the base 30 with the prime inlet 31 to the left and the outlet 34 to the right. The base 30 has a chamber 62 filled with concrete, as at 63, of high slump, tow coarse aggregate. The concrete upon setting becomes a deadweight for the Structural Manhole Assembly that resists hydrostatic and earth forces. The chamber has a deck 61 that slopes down from the prime inlet 31 to the outlet 34 and a floor 60 beneath the chamber 62 with a removable round

[0083] CM / Eifcana Early DN1879 PCT Pat App, 04 / 15 / 26 } 4cover 64 in the center of the floor 60. The chamber 62 serves as a mold or formwork for concrete placed through the aperture as later shown in Fig. 6. As previously shown in Fig. 1, the base 30 welds to the riser 2 opposite the manhole cover 2 and the plate 21 welds beneath the base 30, that is, to the floor 60 and to the riser 2. Alternatively, the invention has the chamber filled with a weighted material such as hydraulic cement, sand, pea gravel, slag, and fly ash.

[0084] The prime inlet 31 then its first throat 35 opens the channelized flow onto the first swale 44 and on its way to the outlet 34. From the prime inlet 31, the base 30 has a slope of at least 0.25 to 1, or 2%, down to the outlet 34 on the right. This slope permits wastewater to flow under gravity alone. The slope appears shown by the deck being higher on the left in the figure than on the right in the figure. Fig. 4 also shows portions of the first throat 35, one of the second throats 36, one of the third throats 37, and the fourth throat 38. The portions of the throats also show in Fig. 4 portions of the first swale 44 by the outlet, the second swale 45, and the third swale 46 towards the left of the figure.

[0085] In an alternate embodiment, the base, particularly the chamber, includes a plurality of stiffeners preferably oriented perpendicular to the plane of the base.

[0086] Fig. 5 shows a perspective view of the base 30 with the inlets 31, 32, 33 having a concave smooth interior that orients flow to the outlet 34, that is, from the left of the figure toward the right. Clockwise from the outlet 34, the base has one second curve 42 the extends to one junior inlet 32, one curve 43 extends from that junior inlet to one lesser inlet 33, one first curve from that lesser inlet to the prime inlet 31, the other first curve 41 extends to the other lesser inlet 33, the other third curve extends form that lesser inlet to the other junior inlet 32, and the other second curve extends from that junior inlet back to the outlet. The inlets, curves, swales, and outlet include

[0087] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 ] 5concavities in their form to prevent accumulation of debris within the base 30.

[0088] Fig. 6 shows a bottom view of the base 30 With its cover 64 removed. The figure thus shows an aperture 66 that receives high slump, low coarse aggregate concrete 63, into the chamber 62. This figure has the outlet 34 in the upper foreground. The base 30 then shows through the aperture the first swale 44 towards the center of the figure, then the second swales 45 upward from the first swale, and the third swales 46 upward from the second swales. The aperture reveals just a portion of the third swales.

[0089] Upon curing during manufacturing, the concrete 63 stiffens and weights the base 30. The base then resists hydrostatic forces and other forces from the nearby earth of an installation. Though this description has emphasized concrete to fill the chamber, the inventors foresee other fillers for the chamber as in sand, pea gravel, slag, fly ash, and the like. The other fillers have a fineness that allows them to fill the chamber and its intricacies beneath and within the deck 61, and the throats above the deck.

[0090] Turning to Figs. 7-12, a preferred embodiment of the Structural Manhole Assembly of the present invention appears as shown in Fig. 7. Fig.

[0091] 7 provides a perspective view and as before, this embodiment has a manhole of the invention as at 10 with its cover M at the top before installation at grade, not shown. Beneath the cover M, the invention has its polymer cylindrical riser 20 welded upon a polymer base, not shown, and upon a plate 21 typically of wider diameter than the riser, a junior inlet 32 into the riser 20, here shown towards the left, in communication with the base, and an outlet 34 out from the riser, here shown towards the right, discharging any fluids or slurries from within the manhole out. Fig. 7 has relationship to Fig. 1 and incorporates the description from above. The outlet 34 has two junior inlets 32 each spaced ninety degrees in rotation away from the outlet to follow American Public Works Association

[0092] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 ]standards, American Society of Civil Engineers standards, or various state Dept, of Natural Resources regulations. The various standards and regulations require a riser structure and its connecting inflow lines and outflow lines to remain in position during their useful lifespan. However, the structures encounter the soil conditions and water tables of their installations. The invention 10 generally presents a hollow cylinder to the surrounding soil and water table. In high water table or swampy locations, the hollow cylinder may displace sufficient water and thus float ever so slowly. That will move the invention as a structure with its inflow lines and outflow lines to rise and move out of alignment. Such rising will affect the flow of wastewater into, through, and out of the invention. This embodiment counters the buoyancy effects and misalignment risks from swampy and high water table installations.

[0093] The ninety degree spacing between the outlet 34 and the two junior inlets 32 provides an exemplary position for a gusset 70 of a planar shape here shown extending radially. The gusset extends outward from the riser 20 to a form 72 of a cylindrical shape with a rounded wall 71 of similar shape as the plate 21. The form rests upon the plate 21 and has a welded connection thereto. The form has a desired height, here ranging from the height of the bottom of the outlet to at least halfway up the height of the riser. Preferably, the form has its height from one to three outlet diameters above the outlet itself. The form has its wall with a thickness sufficient to withstand concrete deadload as later described. In this figure, the wall 71 has two apertures 74 shown that provide communication to the outlet 34 and the left junior inlets 32.

[0094] To overcome buoyancy forces, this embodiment of the invention has concrete, as at 73, placed in the interstices between the riser 20, the form 72, and the plate 21. The interstices arise between the gusset 70 and the outlet 34, the gusset 70 and the junior inlet 32, and from the junior inlet

[0095] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 ] 7around the riser into the plane of the figure. The gusset has a welded or an adhesive connection to the wall 71. The form has its apertures 74 in the wail 71 aligned with the outlet 34 and the junior inlet as previously described. In this figure, the form 72 and the gusset 70 have their heights slightly more than the elevation of the outlet 34. That allows for showing the gusset. The farm and gusset though may have a greater height for introduction of greater volume of concrete and hence more weight applied upon the plate 21 at the bottom of the invention. The concrete provides an amount of weight from this formula: (area of plate [n * (1 / 2 diameter of the plate )A2 less area of riser (IT * (1 / 2 diameter of the riser]A2) * height of wall * 150 Ib. / ft3[density of concrete] * 0.92 [allowance for inlet, outlet, gusset volume losses. Preferably, the manufacturer of the invention provides the concrete into the invention in factory conditions. Alternatively, the invention is shipped without concrete to a jobsite. On the jobsite, the contractor places and sets the invention in position then places the concrete via a drop chute or a hose from a pump truck within the interstices of the invention as described.

[0096] Fig. 8 provides a section view of the present invention similar to Fig.

[0097] 2. As before, the invention 10 has the manhole cover M at the top upon the riser 20 that joins or connects to the plate 21. Proximate the plate, the invention has its base 30 within the bottom of the riser just below the prime inlet 31 on the left and the outlet 34 on the right. Between the prime inlet 31 and the outlet 34 and towards the top of the base, the base has the relief surfaces that receive fluids, slurries, and wastewater with an exemplary surface from a junior inlet 32 shown. The prime inlet 31 extends outward from the riser, that is, to the left in the figure and the outlet 34 extends outward from the riser, that is, to the right in the figure, in this section view, the prime inlet and the outlet have a coaxial alignment. To the left, this embodiment has the form 72 just outside the prime inlet and contacting the

[0098] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 ] gplate 21. The form has Its wall 71 extending parallel to the riser in this figure and the wall extends in height above the prime inlet a desired distance, as specified by the plans and specifications of a job requiring installation of the invention. The plane of section in this figure prevents showing a gusset.

[0099] This portion of the wall 71 has a knockout 75 shown. The knockout has its location as a temporary cover over the entrance to the prime inlet. The knockout here has its orientation on edge. The knockout has sufficient connection to the wall to withstand placement of concrete 73 above it and forces upon the invention during its installation. Following installation of the invention, a contractor removes the knockout 75 for allowing free flow of fluids, slurries, and wastewater into the invention. Beneath the prime inlet, within the wall 71, above the prime inlet, and within the form, this portion of the invention has concrete 73 placed into position to serve as ballast for the invention.

[0100] Turning to the right of this figure, this other portion of the wall 71 has an aperture 74 shown. The aperture has its precise location aligned with the exit of the outlet. The wall 71 of the form 72 fits precisely around the aperture and joins to the outlet in a water tight connection or welding so as to withstand placement of concrete 73 around it and curing of it. Foilowing installation of the invention, a contractor fits an outlet pipe, not shown, into the outlet 34 within its concrete reinforced exit. The outlet then provides for free flow of fluids, slurries, and wastewater out of the invention. Beneath the outlet, within the wall 71, above the outlet, and within the form, this portion of the invention has concrete 73 placed into position for further ballast and even weight distribution around the plate 21.

[0101] Fig. 9 shows a partially exploded view of the present invention partially related to Fig. 1. The invention has its previous form with a cover M at the top of a riser 20 and a plate 21 beneath the riser. Unlike in Fig. 7, the invention may have additional gussets 70. Here the gussets have locations

[0102] CM / Eikana Early DN1879 PCT Pat App, C-4 / 15 / 26 ] 9upon the outlet and the junior inlet, and between the outlet and the junior inlet as previously shown in Fig. 7. The gussets have their planar shape as before and extend radially outward from the riser. The junior inlet and the outlet each have sufficient wall thickness and strength to support the loads imparted upon them by the gussets 70. The gussets have their thickness markedly less than the diameters of the junior inlet and the outlet. The gussets upon the junior inlet and the outlet have their heights that cooperate with the heigh of the gusset between the junior inlet and the outlet so that the gussets shown present a common elevation above the plate, preferably to the height of the form 72. As described above, the form 72 has a round, cylindrical shape with its wall 71 having apertures 74 that align with the outlet 34, the junior inlets 32, and the prime inlet 31. The apertures have their locations in the form to align with any number of outlet, junior inlets, and prime inlet as the base 30 may have. In an alternate embodiment, the wail 71 of the form may have knockouts 75 positioned for the outlet, junior inlets, and prime inlet as specified in the construction documents of a job. Within the form, the riser, gussets, outlet, junior inlets, and prime Inlet, this invention receives the concrete 73 here shown in its plastic state. In a further alternate embodiment, the invention has separately made concrete blocks that fit in the known interstices of the form when joined or connected to the plate..

[0103] Turning to Fig. 10, it provides another section view of the present invention. Fig. 10 relates to Figs. 1,, 9 as previously described. Fig. 10 shows its section through the gusset 70 between the outlet 34 and the junior inlet 32, generally centered upon the plate 21 in Figs. 7, 9. The gusset 70 here has Its rectangular form shown towards the lower right of the figure. The gusset extends radially outward from the riser 20 and joins to the form 72. The top of the gusset matches the height of the installed form. In an alternate embodiment, the gusset has a trapezoidal shape with

[0104] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 20a top edge that starts at the height of the form and then extends upwardly, that is, towards the cover M to its maximum height at the riser. The wall continues around the riser 20 upon the plate 21 and reaches opposite the gusset 70 toward the left of the figure, in this gusset arrangement, this embodiment has full height and width of concrete 73 providing ballast for the invention. The concrete has its height finished to that of the height of wall 71 of the form 72.

[0105] Having shown this embodiment in perspective views and from the side in Figs. 7-10, Fig. 11 shows a plan view of the top of the present invention with gussets 70 spaced away from the other structures of the invention. The invention here has its cover M in the center and upon the top of a riser 20, here shown into the plane of this figure but before placement of concrete into the invention. Similar to a clock, let us begin at the top or 12 o'clock position in the figure. The riser has a junior outlet 32 then turning 45 degrees clockwise a first gusset 70 appearing upon the plate 21. Then rotating another 45 degrees clockwise from the first gusset, the invention has its outlet 34. Rotating the next 45 degrees clockwise from the outlet 34, the invention has a second gusset 70, This second gusset has appeared before in Figs. 7, 9, 10. Rotating to the left, still clockwise 45 degrees from the second gusset, the invention has the other junior inlet at the 6 o’clock position. Rotating clockwise again 45 degrees from the other junior inlet, the invention has a lesser inlet 33 followed by the prime inlet 31 after 45 degrees further rotation to the 9 o’clock position. Then between the prime inlet 31 and the first of the junior inlets, the invention has the other lesser inlet 33. Fig. 11 shows the two gussets 70 spaced within the largest angular gaps between structures in the base 30. The gussets stiffen the form 72 to the riser 20 without contacting the fluid handling structures.

[0106] The Applicant also foresees strong prime inlets, junior inlets, lesser inlets, and outlets, or fluid handling structures. Because of that, Fig, 12

[0107] CM / Eikana Early DN1879 PCT Pat App, 04 / 15 / 26 7 |provides a plan view of the top of the present invention with gussets 70 placed upon select inlets and the outlet 34. Similar to a compass, Fig. 12 shows the gussets placed in the cardinal directions. Similar to a graph, Fig.

[0108] 12 has gusset placement upon the axes. Similar to a clock, let us begin at the top or 12 o’clock position in the figure. The riser has a junior outlet 32 and a gusset 70 upon that junior outlet. Then turning 90 degrees clockwise from the first gusset 70, the invention has its outlet 34 with a second gusset 70 upon it, at the 3 o’clock position. Rotating the next 90 degrees clockwise from the outlet 34, the invention has the other junior inlet at the 6 o'clock position with a third gusset 70 upon it. Rotating clockwise again 45 degrees from the other junior inlet, the invention has a lesser inlet 33. Turning another 45 degrees clockwise, the prime inlet 31 has a fourth gusset 70 upon it as the 9 o’clock position. Further rotation 45 degrees clockwise after the prime inlet, the invention has the other lesser inlet 33. A last 45 degrees clockwise returns to the junior inlet with the first of the gussets 70 at the top. Fig. 12 shows four gussets 70 spaced equiangulariy upon structures in the base 30. The gussets stiffen the form 72 to the riser 20 without affecting the fluid handling structures. Figs. 11, 12 show two arrangements and spacings of the gussets 70. The Applicants foresee arranging gussets in various positions around the riser to suit the requirements of each installation of the invention.

[0109] The invention operates as a manhole device passing a liquid through it by gravity. The device has a cylindrical riser having hollow construction, an interior access space, and a height defining a vertical axis of the invention or device. It also has a round base of hollow construction which then has at least one outlet, and a slope down to the outlet wherein the liquid flows to the outlet. The slope ranges from 0.01 % to 2.2%. The base also has a chamber beneath the outlet that receives a weighted material. The riser joins to the base by one of welding, adhesives, and cohesives.

[0110] CM / Eifcana Early DN1879 PCT Pat App, 04 / 15 / 26 77The chamber has at least one aperture and a closure upon each of the apertures. The weighted material loads into the base through the aperture during factory' assembly of the invention. The invention aiso has a round plate of greater diameter than the riser with the plate being beneath the base. The plate joins to the base and to the riser by one of welding, adhesives, and cohesives.

[0111] The base also has a throat and the at least one outlet receives liquid introduced into the manhole device. Then each of closure upon each aperture in the base has the form of either a plug, a cap, a welded closure, or a bonded closure. Then the base has at least one inlet having a slope down to the throat before the outlet.

[0112] Moreover, the at least one inlet has an embodiment with a prime inlet centered and aligned with the outlet and at least one junior inlet perpendicular to the prime inlet. Each of the prime inlet and the at least one junior inlet discharges into a corresponding throat in the base and each of the throats discharges into a corresponding swale in the base as liquid flows from each swale into the outlet.

[0113] Moreover, the at least one inlet has another embodiment with a prime inlet centered and aligned with the outlet, and at least one lesser inlet at an angle to the prime inlet. Each of the prime inlet and at least one lesser inlet discharges into a corresponding throat in the base, and each throat then discharges Into a corresponding swale in the base as the liquid flows down each swale into the outlet.

[0114] The at least one inlet has another embodiment with a prime inlet centered and aligned with the outlet, at least one junior inlet perpendicular to the prime inlet, and at least one lesser inlet between the prime inlet and the at least one junior inlet. Each of the prime inlet, the at least one junior inlet, and the at least one lesser inlet discharges into a corresponding throat in the base. Each of the throats then opens and discharges into a

[0115] CM / Elkana Early DN1879 PCT Pat App, 0-4 / 15 / 26 7corresponding swale also in the base so the liquid flows from each swale into the outlet.

[0116] Next, the invention has its chamber receiving a weighted material from the group of hydraulic cement, concrete, hydraulic cement grout, fiber- reinforced hydraulic cement, chopped glass reinforced hydraulic cement, sand, pea gravel, slag, fly ash, and water. The riser of the invention is high- density polyethylene while the base is high-density polyethylene. In a further embodiment, the invention has a construction from one of plastic extrusion and rotomoiding.

[0117] In another embodiment, the invention also has a round form being hollow with its diameter more than the riser. The round form has a cylindrical wall joining to the base and the riser by one of welding, adhesives, and cohesives. This other embodiment also has at least one gusset joining to the wall and the riser by one of welding, adhesives, and cohesives.

[0118] An additional embodiment of this factory-assembled structural manhole has a base defining an interior flow path, and at least one outlet connection region, a riser cylinder extending upwardly from the base and joining to it fluid-tight, and the base and the riser cylinder combine into a unitary manhole body configured for gravity flow of liquids through it.

[0119] This additional embodiment alternately has at least one inlet connection region, and the base and the riser cylinder use a thermoplastic polymer material. That thermoplastic polymer material comes from the group of polypropylene, polyvinyl chloride, high density polyethylene, low density polyethylene, nylon, and combinations of them. If materials become critical, the Applicants favor polyethylene.

[0120] This additional embodiment has its construction making its base as rotomolded and the riser cylinder coming from an extruded polymeric cylinder selected from one of a solid-wall cylinder, a profile-wall cylinder,

[0121] CM / Elkana Early DN1879 PCT Pat App, 0-4 / 15 / 26 74and a hollow-core wall cylinder. The base also has a hydraulically contoured bench and at least one sloped flow channel directing liquid by gravity from the at least one inlet connection region toward the at least one outlet connection region.

[0122] The additional embodiment also has its base with a plurality of inlet connection regions arranged at selected angular positions relative to the outlet connection region. Preferably, one of the plurality of inlet connection regions aligns with the outlet connection region upon a principal flow axis and at least one additional inlet connection region at an angle relative to the principal flow axis. The angle relative to the principal flow axis including from 0 degrees to 136 degrees relative to the outlet connection region. Looking at this additional embodiment, its base and riser cylinder combine as a substantially monolithic structural thermoplastic manhole body for factory assembly, and ultimately delivered as a single unit to a jobsite. Optionally, this additional embodiment uses additive manufacturing for the base, the riser cylinder, or both.

[0123] And another additional embodiment of the manhole device of the invention has an upright riser and a base joined to the upright riser where the base has at least one outlet. The base also has a hydraulically contoured internal flow path extending toward the at least one outlet and the flow path has at least one stoped channel region directing liquid by gravity toward the outlet, and an access opening into the base. This additional embodiment also has a plurality of inlet connections and the flow extends from the plurality of inlet connections toward the outlet.

[0124] Moreover, the flow path has a plurality of merging concave flow regions and one of those flow regions directs liquid by gravity toward the outlet. This embodiment also has a round form being hollow and having a diameter more than the riser. The round form has a cylindrical wall joining to the base and the riser. This embodiment next has a weighted material

[0125] CM / Eikana Early DN1879 PCT Pat App, 0-4 / 15 / 26 75within the form selected from the group of hydraulic cement, concrete, hydraulic cement grout, fiber-reinforced hydraulic cement, and chopped glass reinforced hydraulic cement.

[0126] While a preferred embodiment of the Structural Manhole Assembly has been described in detail, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention. With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled In the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. The Structural Manhole Assembly utilizes readily available materials of low costs that neutralize corrosive components in wastewater with minimal shrinkage thus maintaining structural integrity of vessels, tanks, and piping systems. The Structural Manhole Assembly may be manufactured from poly vinyl chloride, high density polyethylene, low density polyethylene, urethane, nylon, other polymers, resins, ferrous metals, nonferrous metals, their alloys, and composites. Alternatively, the Structural Manhole Assembly includes carbon mesh reinforcement or fiberglass reinforcement of the riser. The Structural Manhole Assembly may also have a construction from one of roto molding, plastic extrusion, 3D printing, material deposition, additive manufacturing, and the like.

[0127] In an alternate embodiment, the assembly may further include an adjustable access riser system having a lower threaded assembly joined to the top plate and an upper threaded assembly movable relative thereto to establish a selected installation height.

[0128] Although providing a device often seen from above in residential areas,

[0129] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 7it should be appreciated that the Structural Manhole Assembly herein described is also suitable for oil refineries, chemical plants, factories, mines, mills, plants, wastewater treatment plants, potable water plants, swimming pools, water parks, nonhazardous landfills, hazardous landfills, and the like where workers must access buried lines, sometimes at great depth below the surface.

[0130] Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

[0131] Various aspects of the illustrative embodiments have been described using terms commonly employed by those skilled in the art to convey the substance of their work to others skilled in the art. However, it will be apparent to those skilled in the art that the present invention may be practiced with only some of the aspects described. For purposes of explanation, specific numbers, materials and configurations have been set forth in order to provide a thorough understanding of the illustrative embodiments. However, it will be apparent to one skilled in the art that the present invention may be practiced without the specific details. In other instances, well known features are omitted or simplified in order not to obscure the illustrative embodiments.

[0132] Various operations have been described as multiple discrete operations, in a manner that is most helpful in understanding the present invention, however, the order of description should not be construed as to imply that these operations are necessarily order dependent. In particular, these operations need not be performed in the order of presentation.

[0133] CM / Sfcana Early DN1879 PCT Pat App, 0-4 / 15 / 26 77Moreover, in the specification and the foliowing claims, the terms “first,’’ “second,” “third” and the like -when they appear- are used merely as labels, and are not intended to impose numerical requirements on their objects.

[0134] The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to allow the reader to ascertain the nature of the technical disclosure. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

[0135] As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. Therefore, the claims include such equivalent constructions insofar as they do not depart from the spirit and the scope of the present invention.

[0136] CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 7 g

Claims

CLAIMSWe claim:

1. A manhole device, said manhole device passing a liquid through it by gravity, said manhole device comprising:a cylindrical riser having hollow construction, an interior access space, and a height defining a vertical axis of said device;a round base, said base having hollow construction;said base having at least one outlet, and a slope down to said outlet wherein the liquid flows to said at least one outlet;said base having a chamber beneath said outlet, said chamber receiving a weighted material;said riser joining to said base by one of welding, adhesives, and cohesives;said chamber having at least one aperture and a closure upon each of said at least one aperture;said weighted material loading through said aperture during assembly of said manhole device; anda round plate of greater diameter than said riser, said plate being beneath said base, and said plate joining to said base and to said riser by one of welding, adhesives, and cohesives.

2. The manhole device of claim 1 further comprising:a throat in said base;said at least one outlet receiving liquid introduced into the manhole device; andeach of said closure upon each of said at least one aperture being one of a plug, a cap, a welded closure, and a bonded closure.

3. The manhole device of claim 2 further comprising:said base having at least one inlet having a slope down to said throat before said at least one outlet.CM / Eifcana Early DN1879 PCT Pat App, 04 / 15 / 26 794. The manhole device of claim 3 further comprising;said at least one inlet including a prime inlet centered and aligned with said outlet;at least one junior Inlet perpendicular to said prime Inlet;each of said prime inlet and said at least one junior inlet discharging into a corresponding throat in said base; andeach of said throats discharging into a corresponding swale in said base wherein liquid flows from each swale into said outlet.

5. The manhole device of claim 3 further comprising:said at least one inlet including a prime inlet centered and aligned with said outlet:at least one lesser inlet at an angle to said prime inlet- each of said prime inlet and said at least one lesser inlet discharging into a corresponding throat in said base; andeach of said throats discharging into a corresponding swale in said base wherein liquid flows from each swale into said outlet.

6. The manhole device of claim 3 further comprising:said at least one inlet including a prime inlet centered and aligned with said outlet;at least one junior inlet perpendicular to said prime inlet;at least one lesser inlet between said prime inlet and said at least one junior inlet;each of said prime inlet, said at least one junior inlet, and said at least one lesser inlet discharging into a corresponding throat in said base; andeach of said throats discharging into a corresponding swale in said base wherein liquid flows from each swale into said outlet.

7. The manhole device of claim 2 further comprising:said chamber receiving a weighted material being one of hydraulicCM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 39cement, concrete, hydraulic cement grout, fiber-reinforced hydraulic cement, chopped glass reinforced hydraulic cement, sand, pea gravel, slag, fly ash, and water.

8. The manhole device of claim 2 wherein said riser is high- density polyethylene, and said base is high-density polyethylene.

9. The manhole device of claim 2 further comprising:said manhole device having a construction from one of plastic extrusion and rotomolding.

10. The manhole device of claim 6 further comprising:a round form being hollow and having a diameter more than that of said riser, said round form having a cylindrical wall joining to said base and to said riser by one of welding, adhesives, and cohesives;at least one gusset joining to said wall and to said riser by one of welding, adhesives, and cohesives.

11. A factory-assembled structural manhole assembly, comprising:a base defining an interior flow path, and at least one outlet connection region; anda riser cylinder extending upwardly from said base and joining to said base fluid-tight;wherein said base and said riser cylinder combine into a unitary manhole body configured for gravity flow of liquids therethrough.

12. The factory-assembled structural manhole assembly of claim 11, further comprising:at least one inlet connection region; andsaid base, and said riser cylinder being thermoplastic polymer material.

13. The factory-assembled structural manhole assembly of claim 12, further comprising:CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26 |the thermoplastic polymer material including one of polypropylene, polyvinyl chloride, high density polyethylene, low density polyethylene, nylon, and combinations thereof.

14. The factory-assembled structural manhole assembly of claim 13 wherein the thermoplastic polymer material is polyethylene.

15. The factory-assembled structural manhole assembly manhole assembly of claim 11, further comprising:said base being rotomolded; andsaid riser cylinder being an extruded polymeric cylinder selected from one of a solid-wall cylinder, a profile-wall cylinder, and a hollow-core wall cylinder.

16. The factory-assembled structural manhole assembly manhole assembly of claim 11, further comprising:said base having a hydraulically contoured bench and at least one sloped flow channel directing liquid by gravity from said at least one inlet connection region toward said at least one outlet connection region.

17. The factory-assembled structural manhole assembly manhole assembly of claim 16, further comprising:said base having a plurality of inlet connection regions arranged at selected angular positions relative to said outlet connection region;one of said plurality of inlet connection regions aligning with said outlet connection region upon a principal flow axis and at least one additional inlet connection region at an angle relative to the principal flow axis; andthe angle relative to the principal flow axis including from 0 degrees to 136 degrees relative to the outlet connection region.

18. The factory-assembled structural manhole assembly manhole assembly of claim 11, further comprising:said base and said riser cylinder combining as a substantiallyCM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26monolithic structural thermoplastic manhole body configured to be factory assembled and delivered as a single unit; andwherein at least one of said base and said riser cylinder is formed by additive manufacturing.

19. A manhole device, said manhole device passing a liquid through it by gravity, said manhole device comprising:an upright riser;a base joined to said upright riser, said base defining at least one outlet;said base having a hydraulically contoured internal flow path extending toward said at least one outlet, said flow path including at least one sloped channel region directing liquid by gravity toward said at least one outlet; andan access opening into said base.

20. The manhole device of claim 19 further comprising:a plurality of inlet connections;said flow path extending from said plurality of inlet connections toward said outlet;said flow path including a plurality of merging concave flow regions and one of said flow regions directing liquid by gravity toward said outlet;a round form being hollow and having a diameter more than that of said riser, said round form having a cylindrical wall joining to said base and to said riser; anda weighted material within said form, said weighted material being one of hydraulic cement, concrete, hydraulic cement grout, fiber-reinforced hydraulic cement, and chopped glass reinforced hydraulic cement.CM / Elkana Early DN1879 PCT Pat. App. 04 / 15 / 26

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