# Biomimicry and the Built Environment, Learning from Nature's Solutions
## 3 Biomimicry in Structural Engineering
### Concept of Biomimetics and Structural Engineering Design Process
#### 3.1.3 Structure  
Structural engineers can learn much from nature because it is a self-optimizing system. Nature inspires structural engineers in the process of designing and building a structure that has a high level of adaptability and requires a minimum amount of maintenance. Thus, future structural systems can be considered intelligent, but these basic principles must be first unraveled and understood. Biologists and engineers agree that a systematic analysis in biomimetics is yet to be developed [38]. The structure is the arrangement of different shapes (or members) to solve a given engineering problem. For example, the supporting system of our human body mainly consists of hundreds of bones, ligaments, and tendons. The interrelationship of the bone members has modern applications. The human thigh bone has a high load capacity, which can withstand one ton when in a vertical position. The femur head extends sideways into the hip socket and bears the body's weight off-center. The thigh bone consists of tiny ridges of bone known as trabeculae which are in fact series of studs and braces that are positioned along the force line when standing. The bone structure inspired engineers to decrease the impact of load on the building. In fact, nature strengthens the bone at a level that is required [48]. In 1866, the Swiss engineer [PERSON] translated these findings into applicable theory. In 1889, French structural engineer [PERSON] was inspired by the concept of \"building along the force lines\" to design the Eiffel tower. The curve in the Eiffel tower iron is similar to the curve in the femurs' head. The bending and shearing effects caused by the wind would be transformed into compression [48]. From the Eiffel Tower base (Figure 7), the lattice structure of the studs and braces can be seen. The same approach was utilized to design the World Trade Centre. Bone and joint mechanisms in humans or other animals are one of the most wonderful and simple ways of achieving mobility. It can dislocate the joint under excessive movement or sudden impact without fatal failure in the bone. Furthermore, joints can be relocated again after treatment. Thus, nature has developed a mechanism for repairing and healing itself while adopting simple methods. Suppose this idea can be applied to the field of structural engineering. Thus, engineers may design buildings that can mimic the joint system in humans such that, under the sudden impact (i.e., an earthquake), the building can absorb the energy by dislocating some of its parts and then reconstructing by simply relocating structural connections (joints) back together, which could result in safer buildings and the reduction in construction costs. Spider webs have some geometric features. Spiders manufacture their webs with two distinctive treads to prevent prey break or bounce back from the web: a strong stiff tread for supporting or structural purposes and the flexible and sticky tread to retain the prey on the web [50]. The tree rooting system is a perfect example of inspiration from nature to withstand loading [36] Compressive buttressing, tensile buttressing, and tap rooting are three mechanisms adopted by various types of trees to resist overturning. Although the structural capacity of the amoeba cell is still under research, it is still a natural wonder that a single-celled organism, without any brain or nervous system, can build a simple yet elegant structure. The strategy of having a spherical shape may also demonstrate the wisdom of nature because a spherical shape is proven to have better resistance on impact from arbitrary directions. If the mechanisms of how amoeba constructs the shell are known, engineers and scientists may develop excellent construction processes, which minimize the need for precise calculation and computation power [28]. Honeycomb is another live structure that inspired many structural engineering projects [51].