News Detail

Rules vs. Plays

7/1/2021

I would like to use the July President's Memo to set the stage for a topic you will hear more about over the coming year. I will begin with a sports analogy because sports are useful for clarifying abstract ideas.

Imagine two football teams. One team consists of the league's star players and the other is composed of the league's best referees. Now imagine that they play a game. Which team wins? The players, of course. The referees have a better and more nuanced understanding of the rules, but their good understanding does not translate into good play on the field. To play football or any other sport, a working understanding of the rules is necessary, but well-developed skills for playing the game are critical for success.

Turn your attention now to ACI. We publish some of the best codes and standards in the world. ACI 318, for example, is a globally dominant building code used in many countries and on several continents. Nevertheless, it is a rulebook, not a playbook. It contains the basic requirements—the rules—necessary for protecting the public and for creating safe and serviceable structures. It does not, and should not, contain the “plays” necessary for creating good structural design. The plays are left up to the designer and require a different set of skills.

It takes time and effort to develop these skills because designing efficient and effective concrete structures is difficult. Unlike homogeneous materials such as steel and wood, concrete structures involve a combination of concrete and various forms of reinforcing bar, wire, cable, and fiber. Further, the constituent materials of concrete—aggregates, cement, water, and admixtures—vary from one location to another, and the behavior of concrete under load can be time dependent. Because of all this and more, designing concrete structures can be complicated.

The construction of concrete structures is equally challenging. And it is made even more challenging when communication between the design and construction teams breaks down or when lines of communication are never created in the first place. Inadequate communication leads to key decisions being made in a vacuum, without the collaboration that would have benefited all sides.

One key for designing efficient and effective structures, and a direct benefit of collaboration between the designer and builder, is to incorporate constructability thinking into all major decisions. For example, before deciding on a structural system, it is important to understand such things as the availability of construction materials and equipment, the contractor's preferences in formwork and construction sequence, and the relative costs of labor and materials in the local market. It is in this crucial area of constructability that many otherwise good designs go lacking.

I have observed structures on many occasions that display inadequate constructability input, resulting in unwelcome construction cost increases and schedule delays. Whether due to unawareness of the importance of constructability by the designer, or a contractor unwilling or unable to assist the design team, very different structural designs can follow very similar trajectories. They are well engineered analytically and meet the requirements of the applicable codes and standards but fail to incorporate the constructability that would have allowed the productivity potential of modern construction to be fully realized.

In my May memo, I mentioned the Productivity Task Group and the mission we have been given. In short, we are exploring ways in which ACI can use its resources to improve the productivity of concrete construction. And therein lies the opportunity in the constructability problem. Because the problem is being relabeled a challenge, and the challenge is allowing us to chart an exciting new path forward.

Our task group expects to complete its work this summer and will then meet with the ACI Board of Direction to present our recommendations. They will be multifaceted. None of them will involve diminishing or redirecting the effort that ACI devotes to codes and standards. We will continue our good and successful work in that arena—the rulebooks—for which we are known as global leaders. We will simply devote more effort to the playbooks.

Cary S. Kopczynski

ACI President