Abstract: A universal multi-part form for casting concrete parapets and the like having front and rear surfaces and opposite side and end surfaces with the dimensions between end surfaces varying between parapets. The form comprises a stationary base and support means which has a horizontal upwardly exposed surface for forming a front parapet surface. A first or base end surface form member is mounted on the stationary base and has an upright inner surface shaped in accordance with the parapet base contour. Similar but opposite side surface form members are elongated and slidably mounted on the base with inner surfaces conforming to the desired side surfaces of the parapets. A second or top end surface form member is supported by the base and connected at opposite ends with the side members for adjustable movement therewith.

Abstract: A lifting device for massive precast concrete wall units having spaced parallel front and rear wall panels and spaced apart lateral connecting arms therebetween. The device comprises a pair of pivotally connected lifting legs swingable between retracted and expanded positions. The legs have a spreader element pivotally connected therebetween intermediate their ends. At upper ends a pair of connecting links are respectively connected pivotally at lower ends with the legs and pivotally connected together at upper ends. A lift attachment is also pivotally connected at upper ends of the connecting links. At lower ends the legs have fixed or pivotal shoes with outwardly projecting toes which engage beneath the bottom surfaces of the arms of the wall units with the legs expanded. With the legs retracted the legs and shoes are freely moveable vertically between the arms of the wall units. Shoes are selectively mountable on the legs in pairs with horizontal and at least one other toe angle.

Abstract: Apparatus for breaking concrete and asphalt pavement and the like comprising a frame adapted to be supported by and above pavement to be broken. Power operated means move the frame in one and opposite directions relative to and in parallel relationship with the pavement. A plurality of air hammers are supported in a gang parallel arrangement by the frame with their cutting tools aligned in a closely spaced parallel series. Cutting ends of the tools are adjacent the pavement with the series of tools extending in one direction and frame movement occurs in a direction substantially at right angles relative thereto. Thus, the frame movement defines a predetermined generally rectangular path of movement and pavement breaking operation of the cutting tools. A cradle on the frame is moveable relative to the frame for adjusting both the height and the angle of attack of the cutting tools relative to the pavement.

Abstract: A machine for "dry mix" packerhead concrete pipe manufacture has two stations and a separable tubular jacket movable therebetween. A rotatable cylindrical packerhead is movable axially within the jacket and a "dry mix" delivery means deposits mix atop the packerhead as it rotates and moves vertically upwardly within the jacket. The packerhead distributes the mix thereabout to form a concrete pipe in the jacket. A radially expandable and contractable core is movable axially in a contracted condition to a position within the pipe and is then expanded. Vibrators within the core are operated to "redensify" the pipe; that is, to compact the mass thereof, to eliminate voids, and to relieve residual forming stresses therein. A guide ring is employed to align the contracted core axially with the pipe during entry and further guiding and supporting devices for the core are provided. Core entry and withdrawal is power actuated as is core expansion and contraction within the pipe.

Abstract: Precast concrete structural units and composite wall structure comprising a plurality of the units stacked vertically in horizontal rows. Each unit comprises a pair of laterally spaced longitudinally extending side panels. A pair of laterally extending connecting arms are connected to or formed integrally with the panels at their respective inner surfaces whereby to secure the panels in relatively fixed position. A mortise-tendon connection between superposed units is provided with a vertically recessed mortise at the bottom of each connecting arm and a complementary vertically projecting tendon at the top of each arm. Each mortise and tendon defines a pair of laterally spaced oppositely facing generally vertical bearing surfaces and each mortise and tendon is approximately 1/3 the total width of the associated structural unit. Longitudinal spacing of connecting arms from each other is approximately twice the longitudinal spacing of each arm from the adjacent end of the side panels.

Abstract: A multi-part form for casting concrete structural units having spaced parallel and vertical sidewalls and horizontally spaced parallel and lateral connecting arms therebetween, the connecting arms having mortises at the bottom and tendons at the top. A stationary base and support means has upwardly exposed surfaces for forming the bottoms of the sidewalls and the arms and a core means thereon forms inner vertical surfaces of the arms and portions of inner vertical surfaces of the sidewalls of the structural unit. Opposing movable sidewall form members form outer surfaces of the sidewalls and opposed movable arm and sidewall form members form outer surfaces of the arms and inner surfaces of the sidewalls outwardly of the arms. Sidewall end surface form members on the sidewall form members form the end surfaces of the arms. Tie and strip bolts respectively secure the movable form members in inner assembled positions and urge the members outwardly in a stripping operation after casting.

Abstract: Apparatus for precasting concrete products wherein dry mix is deposited in casting cavities defined by mating upper and base form sections, vibrated and/or pressure compacted, and the upper form section removed immediately for curing of a free standing green cast product. A single upper form section cooperates with a number of base sections and the latter are used to transport the green cast products for curing. Automatically separable base section parts are also employed for the transport of cured products. Forms are adapted for fork lift handling and include high intensity vibrators, sight openings for ascertaining a cavity full condition, closure plates for fill openings, pressure applying and finishing devices, and sectionalized construction for various size products. Casting machine includes mix delivery apparatus and form handling apparatus for upper and base form sections for automated casting and transfer of green cast products for curing.

Abstract: Method and apparatus for precasting concrete products wherein dry mix is deposited in casting cavities defined by mating upper and base form sections, vibrated and/or pressure compacted, and the upper form section removed immediately for curing of a free standing green cast product. A single upper form section cooperates with a number of base sections and the latter are used to transport the green cast products for curing. Automatically separable base section parts may also be employed for the transport of cured products. Forms are adapted for fork lift handling and include high intensity vibrators, sight openings for ascertaining a cavity full condition, closure plates for fill openings, pressure applying and finishing devices, and sectionalized construction for various size products. Casting machine includes mix delivery apparatus and form handling apparatus for upper and base form sections for automated casting and transfer of green cast products for curing.