Adaptive Structures  

Introduction

A New Design Philosophy in Structural Engineering

Designing strength into buildings to prevent collapse has been the underlying tenet of structural engineering since before the ancient Egyptians built the first pyramids.

A second fundamental principle, which appears in all modern design codes, is to build structures that are stiff enough to prevent excessive movement and deformation under statistically-calculated worst-case loads (think: high winds, heavy snow, large crowds). This is not really a question of safety, rather it is about the usability of structures and comfort of the user, termed ‘serviceability’ requirements. 

This requirement to limit movements often demands more material than safety alone, so it raises the question: can it be tackled by other means, without using excessive quantities of concrete, steel, timber or other construction materials? Can we have a different kind of engineering design philosophy?

Adaptive Structures are designed by separating the two engineering principles: using conventional structural materials for safety (a passive system) and another (active) system to control movements, thereby maintaining comfort and usability.Any active system needs power to run, and will use some energy to control movements.

Adaptive Structures provide such a big advantage because most of the time, real structures only experience small loads compared to the ‘worst case’ scenario they are designed to withstand – a football stand being a great example since it only has crowd loading for 90 minutes once per week.

In optimised Adaptive Structures, such as the Adaptive Truss Prototype exhibited here, a passive structure designed for these real loads is supplemented by an active system to achieve a perfect balance of minimum materials and energy.

Background

During his Engineering Doctorate, Gennaro Senatore of University College London developed novel mathematical methods and control systems to design adaptive building structures: namely high performance structures (stiffer, lighter, slenderer) capable of counteracting loads actively by means of actuators, sensors and control intelligence. Using these methods, a full scale prototype of one such adaptive structure, in the form of a very slender space truss with embedded sensors and actuators, was designed and built in collaboration with Expedition Engineering at the UCL Structures Laboratory. The prototype structure performed successfully as predicted.

 

 

       

Generously funded by: