Domain

Explanation

Structures?

• According to the dictionary, the word "Structure" has different meanings as a noun or verb
• As a noun, a structure is something that is built-up, organised and served certain purposes - natural or artificial
• As a verb, to structure something is to design, organize, interconnect and build a pattern or system
• Consider the structuring of structures to serve the intended use

Service lives?

• Due to the complexity of the natural world, conditions are constantly shifting & changing, sometimes abrupt, sometimes undetectable
• To construct a structure for intended use has its service limitation - the period of its ability to remain useful
• Physical and service conditions imposed by the environment & the users constrain the useful period when a built structure is useful
• Natural catastrophes destroy existing structures & allow new ones to sprout on the ashes of the old
• The users abandon useless structures
• Here, 2 issues spring up:

1. With consistent usage guaranteed, how long can structures stand up to the environment?
2. With stable, favourable environmental conditions, how long can structures stand up to volatile usage?

Environmental endurance

• Structures can be designed, built & used for a specific period of time
• Temporary structures: <1 year, built for temporary uses & support other constructions
• Short-span structures: <10 years, built for short-term usage
• Medium-span structures: <50 years, nominal design usage
• Long-span structures: <100 years, top of modern commercial design usage
• Monumental-span structures: <500 years, nominal period for symbolic monument of historical, cultural & artistic meaning: Statue of Liberty, Eiffel Tower
• Millennial-span structures: <1000 years, top of monumental design period, mostly of historical & religious background: York Minster Cathedral, Lhasa Monastery
• Quad-decade-span structures: <10,000 years, nominal period for royalty, religious & ancestral worship: Pyramids, Stonehedge, Maoi statues
• Continuous-span structures: >10,000 years, limitless period: natural evolving structures

Volatile deterioration

• Artificial deterioration to existing structures
• Unintentional: accidents, pollution, misguided usage, times of hardships, wars & disasters
• Intentional: wars, mutual annihilation, misguided blindness, desires