INGENIEUR
INGENIEUR
challenges . Earthen homes are generally best suited to hot and dry climates , since earth is a thermal mass and responds well to daily and seasonal changes in temperature . Structurally , earth has good load-bearing and compressive strength , but is much weaker when it performs in tension . Additive materials like straw ( used to make cob ) will enhance tensile capacities while structural frames made from wood or bamboo ( used for rammed earth and adobe ) can absorb perpendicular forces . Tensile and structural reinforcement also improves resistance to certain climatic challenges such as strong winds and earthquakes though generally earth may not be the best choice in disaster prone areas .
Different types of earth constructions have varying abilities to tolerate humidity and water . Long roof overhangs , finishing materials such as cement or plaster and high foundations will all help to protect earth structures from water . For all kinds of earth construction is it important that the quality of the soil be assessed before using it . Mineralogical composition , grain shape and size , and particle distribution all affect soil quality and the overall durability of the finished structure .
Responsible sourcing of soil , sand and clay should be considered since extracting from certain sites such as riverbeds can have negative environmental impacts like increasing erosion .
MCKINSEY & COMPANY
The McKinsey Global Institute estimates that the world will need to spend US $ 57 trillion on infrastructure by 2030 to keep up with global GDP growth . This is a massive incentive for players in the construction industry to identify solutions to transform productivity and project delivery through new technologies and improved practices .
Disrupting construction - Five big ideas All five ideas are grounded in innovations that are applicable to the construction sector and that are either being deployed or prototyped . In short , they are practical and relevant . Moreover , they are designed to work together to deliver greater impact :
1 . Higher-definition surveying and geolocation- Rapid digital mapping and estimating
2 . Next generation 5-D building information modelling – Design platform for the future
3 . Digital collaboration and mobility – Moving to paperless projects , from the office to the workforce .
4 . The Internet of Things and advanced analytics – Intelligent asset management and decision making
5 . Future-proof design and construction – Designing with materials and methods of the future .
Building materials represent a US $ 1 trillion global industry ; materials usually account for more than half the total cost of projects . Traditional materials such as concrete , cement , and asphalt make up most of this demand . But new and better construction materials are also required due to several trends :
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Green construction . There is an immense push to adopt materials and technologies with lower carbon footprints .
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Cost efficiency . Given substantial cost pressures , there is a need for structural change in the choice of materials , in addition to incremental lean efforts .
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Supply-chain agility . Transporting heavy materials and equipment has massive implications on supply-chain costs and time , especially because many new projects are located in remote or dense areas .
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Improved durability and strength . With capital costs rising and land growing scarce in many markets , owners are insisting that projects have longer commercial lives .
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Off-site construction . Assembling lighter , easier-to-handle materials off-site can improve project efficiency , address onsite space constraints , and create the conditions for crews to improve their skills .
There has been a wave of innovation in construction materials over the past few decades , developed with specific uses in mind . There are dozens ; here are a few that are particularly interesting : Self-healing concrete . This uses bacteria as a healing agent to close cracks on concrete ; it is currently at the proof-ofconcept stage . Concrete canvas . Take a layer of “ concrete cloth ,” then add water and allow to set . This innovation typically is used for drains ,
76 VOL 69 JANUARY-MARCH 2017