Precast Concrete Structures: The F1 of Construction

Surely, all readers have already seen infrastructure projects made with precast/prestressed concrete structures. Who has not passed by an elevated highway under construction (and suffered the inconvenience during the construction process) or seen how rapidly the new shopping center being built in their neighborhood goes up? Other equally relevant prefabricated pieces are not visible due to their location, such as the prefabricated ring segments that form the deep drainage tunnels of Mexico City. Today, we are surrounded by prefabricated constructions.

Why have these building systems increased in popularity? It is because pre-existing prejudices regarding these systems have been overcome: that they are more expensive, that they do not work in Mexico due to earthquakes, that they are not practical because our labor or salaries are very cheap, they do not adapt to the architectural designs, that there are not enough producers, and so on. When returning from a trip abroad, especially from the United States, where precasts are also very common, the conversation with our construction friends goes more or less like this: “In the US, everything is prefabricated. They arrive with everything done and they just arm it like a Meccano. They are very fast. In the week that I was there, I witnessed how they advanced a good part of the project. They don't use fake work, just a huge crane that assembles one piece after another." Indeed, all of this is true and it is gradually being proven in Mexico as more projects are executed using precast.

Industrial or Artisanal Construction?

Industrialized work is the ideal of the builder but it is necessary to answer honestly when questioned if it is built in an industrialized way or simply using concepts equal to those of other projects. Are processes repeated identically? Are resources maximized? In reality, this is not the case, and it is very difficult to compare these construction projects with the manufacturing of a car or a fitted kitchen. That being the case, one might be resigned to believe that the so-called construction industry is actually a multimillion-dollar craft, doomed never to progress toward standardization. However, many efforts have been made to achieve homogenization and improve processes.

Recently, I saw a video comparing the entrance to the pits of a Formula 1 car in 1950 and in 2013: in the first case, changing the four tires, cleaning the windshield and filling the car took 67 seconds — certainly very little — but in 2013, it took less than three seconds! A timeframe that was already minimal had been decreased 20 times! With or without a load of fuel, it is true that these people have studied all the implications, not only the mechanical work at the time, but also, and of course, the design of the car.

What is the reason for abbreviating a simple pit stop so much? Those seconds are the difference in winning a world championship. If one team has taken a second from the process, or a tenth of a second, the other must achieve it as well. There is an absolute vocation to study, do, improve, do again and achieve. This fact prompts us to reflect on whether there is the capacity to do the same in construction and how it can be achieved.

The answer lies in how the work itself is carried out and not in cornering the architect so that he always does the same thing (on the contrary, nor does his work always have to be so different). It is in reconciling the important aspects that allow a true acceleration of construction procedures. Some points that make a big difference are highlighted below.

Plan

Starting the project in advance and placing the highest importance on the activity that takes place in the office translates naturally and forcefully into better results in the field. Abraham Lincoln said: "Give me six hours to cut down a tree and I will spend the first four sharpening my ax." Perhaps the mechanic who changes the wheel of the Formula 1 car, that simple mechanic, has led to the creation of the most sophisticated nut in the world.

Define

Making plans, creating sketches, spending paper or megabytes on drawing ideas is fine but there comes a time when you have to decide and define and then move forward. As the precast requires time before it is placed on site, it becomes the enzyme that pushes the definitions forward. In this very important stage is the conception of the car that will win the race; here, the car of the future is born. This is then quickly translated into construction plans.

Organize

Moving forward is fine, as long as it is in the right direction. It is useless to produce many precasts if it is not possible to assemble them because the foundation of that area of ​​the project has not been built or because the preceding pieces are not yet manufactured and ready to be assembled. That is why the sequential organization of the entire project, starting with the engineering, is one of the most powerful ways to reduce total times. A job that is only 3 seconds long must be well organized!

Run

The clean execution of the work, with the necessary structural safety, quality and accuracy, is undoubtedly the only thing that will remain forever, after the construction stage and costs have been exceeded. That is why it is important that full attention and care be given to execution. Otherwise, a wheel can come off the car in a curve.

Continue

When the structure has been erected quickly, it is feasible — and indispensable — for the rest of the disciplines to accelerate in turn and begin their work immediately. Every week, large areas of the structure are completed that allow very good performance of masonry, finishes, installations and facades, which makes it desirable to reduce execution time significantly in these areas as well.

Is it possible to reduce time and costs? Of course. And for this, nothing will be better than allying with companies that follow mechanized processes; the result will be achieved when everything is optimized. Start earlier. Greater predictability. Less precedence. Save older clearings. Maintenance is not required, etc.

In addition to all these advantages, in this time of COVID 19, reducing the number of people working on the construction site will represent an incalculable advantage for any construction system that achieves it. And certainly the precast is the system that can do it best.

Between 1950 and 2013, there are 63 years. The joint effort of architects, structuralists, builders, owners, and, of course, the precast manufacturing companies will surely reduce the "time in the pits" of construction 20 times in much less than 63 years. It is only necessary that those who have not done it yet, start, and those who have already started, keep working.