Resilience (engineering and construction)
In the fields of engineering and construction, resilience is the ability to absorb or avoid damage without suffering complete failure and is an objective of design, maintenance and restoration for buildings and infrastructure, as well as communities.
[5] The built environment need resilience to existing and emerging threats such as severe wind storms or earthquakes and creating robustness and redundancy in building design.
[10] The term was used to describe a property in the strength of timber, as beams were bent and deformed to support heavy load.
Tredgold found the timber durable and did not burn readily, despite being planted in bad soil conditions and exposed climates.
These definitions can be used in engineering resilience due to the application of a single material that has a stable equilibrium regime rather than the complex adaptive stability of larger systems.
Resilience was used to describe people who have “the ability to recover from adversity.” One of the many researchers was Professor Sir Michael Rutter, who was concerned with a combination of risk experiences and their relative outcomes.
Ecological resilience was defined as a "measure of the persistence of systems and of their ability to absorb change and disturbance and still maintain the same relationships between state variables.
The random events described by Holling are not only climatic, but instability to neutral systems can occur through the impact of fires, the changes in forest community or the process of fishing.
Multiple state systems rather than objects should b studied as the world is a heterogeneous space with various biological, physical and chemical characteristics.
Within this framework, resilience is calculated based on the time it takes a system to return to a single state equilibrium.
Buildings operate at multiple scale and conditions, therefore it is important to recognize that constant changes in architecture are expected.
Early planning can help prepare and design for the built environment based on forces that we understand and perceive.
In the operation phase of the building, a disturbance does not mark the end of resilience, but should propose a recovery plan for future adaptations.
Shocks are natural forms of hazards (floods, earthquakes), while stresses are more chronic events that can develop over a longer period of time (affordability, drought).
It is important to understand the application of resilient design on both shocks and stresses as buildings can play a part in contributing to their resolution.
For earthquake hazards, the rating relies heavily on the requirements set by the Building codes for design.
Transaction rating system provides a building with a report for risk exposure, possibly investments and benefits.
Due to the current focus on seismic interventions, the USRC does not take into consideration several parts of a building.
The program helps facilitate the resilience plans in cities around the world through access to tools, funding and global network partners such as ARUP and the AIA.
RELi is a design criteria used to develop resilience in multiple scales of the built environment such as buildings, neighborhoods and infrastructure.
RELi provides a credit catalog that is used a s a reference guide for building design and expands on the RELi definition of resilience as follows: Resilient Design pursues Buildings + Communities that are shock resistant, healthy, adaptable and regenerative through a combination of diversity, foresight and the capacity for self-organization and learning.
RELi also combines specific hazard designs such as flood preparedness with general strategies for energy and water efficiency.
The menu format of the catalog allows users to easily navigate the credits and recognize the goals achieved by RELI.
The pilot credits are found in the Integrative Process category and are applicable to all Building Design and Construction rating systems.
For example, earthquakes that took place in the Wenchuan County in 2008, lead to major landslides which relocated entire city district such as Old Beichuan.
It is difficult to discuss the concepts of resilience and sustainability in comparison due to the various scholarly definitions that have been used in the field over the years.
[33] Both concepts share essential assumptions and goals such as passive survivability and persistence of a system operation over time and in response to disturbances.
Holling and Walker argue that “a resilient sociol-ecological system is synonymous with a region that is ecological, economically and socially sustainable.”[34] Other scholars such as Perrings state that “a development strategy is not sustainable if it is not resilient.”[35][36] Therefore, the two concepts are intertwined and cannot be successful individually as they are dependent on one another.
For example, in RELi and in LEED and other building certifications, providing access to safe water and an energy source is crucial before, during and after a disturbance.
A system may be partially functional when a hurricane strikes and may not be fully recovered due to uneconomic cost-benefit ratio.
