Frequently Asked Questions

Q: The need of aligners in all walls

A: Usually only placed in long walls, but in case the client needs it, can be placed on all the walls. We refer to long walls as those walls from 3m length onwards. Also, we place aligners on walls where there are door openings, so as to ensure the alignment of both sides of the frames. In case of very short walls where door’s orifices are present, generally the placements of aligners are not necessary.

Q: The need of Double aligners on the long walls

A: Usually not needed, but in case the client needs it, it would be placed only in long walls. Double aligners are not required in the Aluma EasySet system, because the formwork of the walls have a positive connection (via pin/wedges), at the top where it connects with the slab formwork. In the joint between the vertical or wall’s formwork and the horizontal or slab’s formwork, it incorporates a unique stripping joint system (incorporation of side rails at panels with an angle different then 90° with respect to the contact face) that provides alignment to the upper portion of the walls. As a result, the system only needs aligners in the bottom part of the formwork and also according to the guidelines discussed in the previous section. We have seen in other aluminum formwork systems that use the mechanism of “Slip Plates” or “Slide plates”, that the use of this mechanism can speed up the stripping process but at the same time the system or wall formwork works independently from the system or slab formwork, which leads to the use of double aligners or aligners at double height (bottom and upper portion of the wall formwork), to keep all the formwork aligned. In short, the mechanism of “Slip Plate” or “Slide plates” on one hand provides the benefit of speeding up the stripping process but otherwise it greatly increases the possibility that the formwork structure doesn’t align properly.

There are available systems on the market of aluminum formwork for monolithic casting that incorporate this mechanism and call it differently, (Flat Slab Wall Union), but the principle is the same. For decades we have successfully used the mechanism “Slip Plate” in other applications, for example in concrete structures that vary in size, (ground floor), such as formwork systems for hanging bridges piers. In this example the mechanism is ideal, as it does not compromise in any form the alignment of the formwork.

The system “Slip Plates” or “slide plates” do not need to be incorporated in the Aluma EasySet System because EasySet is built with panels extruded and designed to specifically supply inclined stripping joints (at the vertical and horizontal level of the formwork of the walls and slabs). These panels or joints provide a fast stripping mechanism without affecting the integrated nature of the walls and slabs, creating the bracing at the top of the walls

Q: The need of a plumbing brace in every location

A: Yes, they are required and included in our System. The plumbing braces are not necessary in all locations, only on long continuous walls (of 3m or more in length) without intersections with other orthogonal walls.

Q: The need for prior knowledge of the rigidity and strength of the catwalk bracket support, which appear to be very fragile

A: It is best that the client sends us the special requirements for the catwalk bracket support so we can verify that it meets these requirements. If not, we will redesign them to meet the given requirements. The capacity of our catwalk brackets is based on a minimum 2:1 safety factor. In short, the catwalk brackets of 1 meter wide have a capacity of 3.5 kN, (3.5 kilo-Newtons or 357 Kg), on the other hand catwalk brackets of 60 cms. wide have a working capacity of 2.1 kN (2.1 kilo-Newtons or 214 Kg).

Q: The rigidity of the panels is considerably increased if the width of the extrusion is 10 cm instead of 15 cm. Based on what criteria is the width to be used for a particular project determined? I believe in our case, extrusion’s widths of 10cm. would be preferable.

A: That is determined by our Engineering Department, when designing the formwork to be used in your project. The combination of the extrusions depends entirely on the specific width of each panel and is not dependent on the project. Found below are some of the Aluma EasySet extrusions:

Independent of the combination of extrusions on the panels, the system EasySet is designed to support concrete pressures (with safety factors already incorporated) maximum 60kN / m² (60 kilo-Newtons / m² or 6116 kg / m²).

Q: Is the possible pivot angle (for stripping) in the bottom of the vertical panels actually necessary?

A: It is possible, although not necessary, but would improve the stripping speed. To significantly improve the stripping process (make it easy & quick), the pivot angle is necessary on systems that do not have the stripping joints, (or panels with angles other than 90° between the contact face and side rails). Using these angles in the EasySet system is not required; our customers generally do not use it, but can easily be incorporated.

Q: At the formwork of the facade, are there also vertical joints to facilitate stripping?

A: There are no stripping joints at the façade’s formwork, as they are not necessary, because the stripping starts by the corner angle, which functions as a stripping joint.

Q: What is the actual performance of a complete stripping-assemble-poured cycle for the Salvador (Brazil) apartment project, expressed in man-hours per m2 of floor area? I would like to have more information about this project.

A: Find below more detailed information about the Salvador project.

  • Approximate Contact Area per set: set of formwork for ½ floor (approx. 500m ²).
  • Average worker’s quadrille, (½ floor): 20 workers
  • Average length of formwork stripping cycle per set (½ floor): 7 hours
  • Average labor productivity per set (½ floor): 3.57m ² / hour / worker
  • Estimated concrete volume: 65 m³ for ½ floor.
  • Full-time completion for ½ floor (includes shuttering and stripping of the system, placement of facilities, steel and concrete pouring): 12 hours (7am-7pm).
  • Setting time before beginning the stripping process: 12 hours.

Q: We would like to see in detail the stiffener’s design that closes the window and doors frames in order to know its rigidity, as in all our projects and other promoters, there have been problems of vertical and horizontal deflections or bending’s on the doors and windows closures, which makes it very difficult to standardize the openings of these elements. For this reason, we believe that these openings must have vertical (simple) and horizontal (twice) shoring, that guarantees the accuracy and equality of all the openings in order to use standardized doors and windows.

A: In all the projects that are currently running with our system, no client has informed us that this drawback has presented itself. The lateral closures or lateral bulkhead of the doors and windows do not need bracing, they are designed to withstand at least the same concrete pressure as the system itself (60 kilo-Newton/ m² or 6116 kg/m²). Regarding the horizontal closures or bottom lintels on the doors and windows, they do not need any propping up, about a lintel’s horizontal length of 1.8mts. This last criterion should also be evaluated together with the depth of the lintel, which could make the above criteria vary slightly. In the below figures you can appreciate the section of standard bulkheads for 100mm thick walls, (“100 BULKHEAD PANEL”), and the non-standard bulkhead (“NON-STANDARD BULKHEAD PANEL”), and their respective dimensions.

Q: On semi-detached buildings; how do you solve the case of shuttering and casting the walls that are in contact with each other, where it requires ties that are at least twice the width of each wall?

A: Yes, longer ties are supplied, and an angle which allows for removal of the internal formwork. We refer to construction joints within a concrete structure as per the below figures:

Now the next pouring: after solving the joint construction as described above, through the use of longer ties, that particular detail is very similar as when we attach the starter panels as shown below, (the difference would be in the length of the tie):

On the other hand, when we refer to continuous casting or pouring of two independent concrete structures (such as the project “Hotel Tucacas” in Venezuela), we usually follow the below typical pouring sequence: