In the evolution of structures, architects and engineers have always tried to build longer spans that were aesthetically pleasing, structurally efficient and readily fabricated. There have been many stages in this. Two of the most important are the development of the metallic skeleton, and the use of the shell form as a structure.

It was Buckminster Fuller first combined these ideas in his geodesic domes in the 1950’s. But Fuller’s work was limited to circular domes - spherical sections.

In the 1960s a Canadian inventor, Arthur Fentiman, developed a mechanical joint that provided for the flexibility to do free-forms. The joint allowed construction of structures with simple fabrication and without welding. Most importantly, contrary to other joints available, it transferred bending across the connection.

This enabled the first uses of free-form gridshells. These domes were built in Mexico. They were built by Francisco Castano Senior in the 1960s. Many of them are still in use.

This, for example, is the Mexico City Sports Palace, built for the 1968 olympic games. It is a 150m span arched dome designed by architect Felix Candela.

Geometrica’s precursor built the hyperbolic paraboloids that infill the main arches.

Free-forms are possible because the tubes can accommodate curvature and a change of angle in the geometry. The “coining angles” provide for curvature along the tube direction, and the twist provides for variation in the curvature in the other direction and allow the change in direction of principal curvature.

There is a sample tube and hub that is circulating. Feel free to take it apart.

The moment capacity of the joint permits single or vierendeel geometries. These are true space-frames. As well as the traditional 3D-truss geometry systems. Single layer and vierendeel geometries are ideal for gridshells because shell forms do not need to carry large shears. Further, the geometries eliminate visual noise.

The grid can take on almost any geometric pattern.

This technology was available back in the 1960s, why wasn’t it used more? Two issues remained: One, the joint did not provide for ductile behavior. That is, the joint failed before the tube material. Two, the software to design these free-style structures was not readily available.

Geometrica solved these issues.

In the 1990s we developed an improved joint. Geometrica’s patent redesigned the hub so that it achieves ductile behavior. The Geometrica hub develops 130% of the yield strength of a steel tube.

This means that the joint is stronger than the specified tube strength. Now we get the failure away from the joint as the tube stretches in yield. Ultimate failure is usually at the joint, but this happens well after tube yield. Occasionally the ultimate failure even occurs away from the joint, as per the second specimen in the photo.

And the second issue was solved with software. These days there is, of course, commercial software that allows design professionals to create beautiful geometries. But there still lacks a connection between this software and the actual built structure. Geometrica has a world-class proprietary software and the hardware to bring those creations to reality in an efficient manner.

Structures can be built where every single bar is different from every other. This, for example, is a roof for a multi-use hall covering about 1000m2.

We call these structures Freedome, a contraction of free-form dome. You can see here the use of natural lighting.

Freedomes can be used for shopping centers, houses of worship, museums, stadiums, canopies, arias and hospitality venues.

This is an aviary. Formed by two spheres connected by an anti-clastic surface. Metallic mesh was placed as cladding.

A museum in Malta with a Free-form veil. Since this is a planetarium the architect wanted to represent a sphere falling from space on to the museum, which deforms in to a wavy shape.

A swimming pool dome in Taiwan. Depending on the projects characteristics we can offer different types of materials, in some cases with the special finishes such as the ones needed for a corrosive environment like the one inside a pool.

The structures are affordable. They have been used for distinctive industrial buildings such as these manufacturing plants that span 84 x 224m (275 x 735ft) with no interior columns.

Or these domes for environmental protection in Florida. They span 122m (400 ft) free of columns and, besides protecting the environment, they give a distinctive look to the plant. They may be the largest coal storage domes in North America.

This mosque is in Male, Maldives. The Maldives are a set of paradise islands in the Indian ocean. We had a riot in the office because everyone was fighting over the tickets to supervise installation of this job.

This one is in Qatar, a storage and transfer station for a waste to energy facility.

With the Geometrica system, free-form can be selected because its efficiency is true. Many systems promise such efficiency, but there is a sticker shock when the structure is actually designed. That is not so with industrial facilities because those clients choose the building system almost solely due to its economics and efficiency.

Geometrica enables free-form for many projects where such interesting architecture would not have been economically feasible.

We have built several of the largest free-style domes in around world. This is the Glory Sanctuary in Nigeria, a church in Nigeria that houses 150,000 faithful. It is currently the largest church in the world.

Installation is simple. You only insert the coined end of the tube inside the connector. To build subassemblies.

The tubes can be made from galvanized steel or aluminum and painted in any color.

Subassemblies (spiders) with three tubes are laid out on the ground under the growing dome. Near to where they will be installed.

And when the time comes, they are hoisted to the work front.

Workers use PPE. Full body harness, double lanyard, lifelines and anchors.

They can work off manlifts, or…

…off the structure itself, or…

…assembling on the ground and using a lifting tower

Until the dome is complete.

At which point the crews usually celebrate.

When we started it was a little difficult to sell the free-form structures, as all we had to show were computer graphics.

But as the structures were built, it became easier. And people would actually believe that we could bring these impressive geometries to life.

The system can accommodate anti-clastic surfaces. These are surfaces that curve in opposite directions.

Like this church. The architect wanted the form to inspire WORSHIP, and I think he succeeded.

And if you turn it upside down, the form can be used for storing water.

This structure stores 2500m3 (660,000 gal) of drinking water and maintains the desired water pressure for a large subdivision. The Geometrica structure was used as formwork but since it is so aesthetically pleasing, there was no need to remove it.

The system can be used for secondary structures or cladding support. façades.

As it was used in the Soumaya Museum in Mexico City. This building has over 100,000 tubes, none of them identical to any other. These tubes work as a support for the hexagonal cladding which ends up giving the final touch to this impressive structure.

Sistema GR-38

Cladding can be as simple as metal deck or standing seam roof.

Sistema GR-38

To a waterproofed with single-ply membrane or any other system available for non-curved structures.

In Soumaya we used a metal deck, a waterproofing membrane, and then the hexagonal aluminum panels.

Sistema GR-38

Acoustic ceilings or thermal insulation can be accommodated between the layers of the structure to protect the inside of the building from hot or cold weather. The space between layers can range from 400 to over 1500mm (16” to over 5’)

Skylights can follow the cladding layout as in this 80m x 120m (250 x 400’) velodrome creating beautiful patterns. This structure features a vent cap for natural ventilation.

Sistema GR-38

Or they can follow the structural pattern. The geometry of each module of the mesh.

As shown in this picture, glass is also an options for our structures. AND we offer a waterproof cladding system.

Sistema GR-38

Most skylights leak after a little while. This is because they depend on the silicone seals for waterproofing.

Geometrica has a skylight system that, contrary to other skylights, this does provide for full redundant waterproofing. It has a three-way gutter system that can carry any infiltrate or condensate from the water break all the way to the edge through a flexible continuous gutter system.

Sistema GR-38

Geometrica has a skylight system that, contrary to many free-form skylights, this does provide for full redundant waterproofing. Primary, secondary and tertiary supports.

This allows Geometrica skylights to mix opaque and transparent panels. The bar amount increases in the corners to reinforce this area of the structure, but don’t worry, because the connector is not the most expensive part of the Geometrica system. We are free to reinforce specific areas and have smaller or bigger bars without boosting the overall price of the structure. Our bars are typically from 1 to 2 meters and we can go up to 4m. The same with the diameter of the bars, we can use up to 6 inches, but 4 or less are used typically.

You can use tinted, insulated glass as in this dome at Mustafa Center in Singapore.

Or clear glass for access to the Caribbean sky as in this Children’s museum in Puerto Rico.

And if still more sky is required, the dome may be made openable.

And if still more sky is required, the dome may be made openable.

These monumental skylights incorporate double curvature.

In England, Southampton Water, a waste to energy facility had a difficult time getting built. This because the local authorities would not approve the project due to poor aesthetics.

Southampton Water is where the most famous cruise ships Queen Elizabeth and Queen Mary dock. They did not want an ugly power station nearby.

The developer retained Jean Robert Massaud, an architect in Paris, who proposed a Geometrica dome and got the project’s approval.

Here is one of our latest freedomes. It is an industrial project, but it illustrates the whole delivery process of a Geometrica dome in only 7 months.

As you can see the plan for this freedome approximates a triangle, its shortest side is close to 152m and its longest side reaches 207m.

And a second Freedome is now almost finished at the same plant. This one has 179 x 182m span. More than 40 meters height.

One question remains… What can Geometrica do for you?