Rachel Armstrong: Architecture that repairs itself?

Video at:  http://on.ted.com/4R

Common Air Leakes

Connect to Insulation handbook [electronic resource]  from u of t library here:

http://main.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=27459

Aerogels: Their History, Structure, and Applications

http://geobeck.tripod.com/frontier/aerogels.html#link

http://www.aerogel.com

“Aerogels for thermal insulation”

http://findarticles.com/p/articles/mi_hb6547/is_2008_July/ai_n29447661/

http://www.sti.nasa.gov/tto/spinoff2001/ch5.html

Thermal Insulation

The term thermal insulation can refer to materials used to reduce the rate of  heat transfer, or the methods and processes used to reduce heat transfer. Heat energy can be transferred by conduction, convection, radiation or by actual movement of material from one location to another. For the purposes of this discussion only the first three mechanisms need to be considered. Thermal insulation is the method of preventing heat from escaping a container or from entering the container. In other words, thermal insulation can keep an enclosed area such as a building warm, or it can keep the inside of a container cold. Heat is transferred by from one material to another by conduction, convection and/or radiation. Insulators are used to minimize that transfer of heat energy. In home insulation, the R-value is an indication of how well a material insulates. The flow of heat can be reduced by addressing one or more of these mechanisms and is dependent on the physical properties of the material employed to do this.

Common 100 amp Breaker Panel Described

Domestic Electrical System Overview

 

Need help understanding all this? Me too ask Larry Dimock aka Circuit Detective @ www.thecircuitdetective.com

Metal Matrix Composites

Metal Matrix Composites (MMC) have been the subject of scientific investigation and applied research for about three decades, but these advanced materials have been introduced only gradually in particular engineering components, such as space shuttle and satellite components, jet fighter aircraft parts, combustion engine components, brake rotors or heat sinks for electronic systems. their greatest asset is the combination of properties of a metal matrix with those of a reinforcement, usually ceramic, providing a potential for tailoring material properties to meet specific and challenging requirements. there is a great variety of material combinations (ingredients, volume fractions and shape, processing) giving rise to a wide spectrum of types of mmc, each with a specific property profile. on the other hand this extraordinary variety complicates the know-how transfer to industry and hinders the acceptance by engineers developing new products.

Self-Healing Composites_Concrete Example

More flexible than traditional concrete, ECC acts more like metal than glass. Traditional concrete is considered a ceramic. Brittle and rigid, it can suffer catastrophic failure when strained in an earthquake or by routine overuse, Li said. But flexible ECC bends without breaking. It is studded with specially-coated reinforcing fibers that hold it together. ECC remains intact and safe to use at tensile strains up to 5 percent. Traditional concrete fractures and can’t carry a load at .01 percent tensile strain.

The average crack width in [the] self-healing concrete is below 60 micrometers. That’s about half the width of a human hair. His recipe ensures that extra dry cement in the concrete exposed on the crack surfaces can react with water and carbon dioxide to heal and form a thin white scar of calcium carbonate. Calcium carbonate is a strong compound found naturally in seashells. In the lab, the material requires between one and five cycles of wetting and drying to heal.

Self-Healing Composites_Carbon Fibre Reinforced Polymer Example

Self-healing is a novel alternative to damage tolerant design and removes the need to perform temporary repairs to damaged structures. It derives inspiration from biological responses to damage, such as the human process of haemostasis, in order to impart an autonomous healing functionality into a composite material. This technology has the potential to mitigate damage resulting from an impact event, thereby providing an opportunity to improve the design allowables or offer other benefits such as reduced maintenance and inspection schedules.

When a microcrack forms in the composite material, it will spread through the material. By doing so, this crack will rupture the microcapsules and release the healing agent. This healing agent will flow down through the crack and will inevitably come into contact with the Grubbs’ catalyst, which initiates the polymerization process. This process will eventually bond the crack closed. In tests, the self-healed composite material regained as much as 75 percent of its original strength.