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Chapter 3-1 Sustainable material, concrete.ppt
- 1. Sustainable (Green) CONCRETE Organized byBahiru Bewket(PhD)
- 2. Organized by BahiruBewket(PhD)
- 3. Concrete is Essentialin every Market After water, concrete is the most widely used material in the world 2x more than plastic, steel, aluminum, wood and combined CO2 from cement: Global = 5% U.S. < 1.5% Organized by Bahiru Bewket(PhD)
- 4. Cement. Key Reactions CaCO3,calcium carbonate, is usually obtained from limestone CaCO3 CaO + CO2 @ 1,100 to 1,650 °F → Clinkering (combining CaO) with silicates, aluminates and ferrites) requires additional energy Combustion 35 – 40% Calcining 60- 65% Organized by Bahiru Bewket(PhD)
- 5. Industry Improvement Results EnergyUse decreased by 37% Cement Kiln Dust decreased by 75% Organized by Bahiru Bewket(PhD)
- 6. Continuous Improvement Goals By2020 the following reductions: Reduce carbon dioxide - 10% * Reduce energy use – 20% * Reduce cement kiln dust – 60% * Environmental Management Systems Organized by Bahiru Bewket(PhD)
- 7. Sustainable must beDurable Optimal material utilization – less waste from replacement Lower maintenance costs Lower total cost of ownership Long life Organized by Bahiru Bewket(PhD)
- 8. Less Frequent Reconstruction(Longevity) Lessraw materials Cement, aggregates, steel Lower energy Manufacturing , construction, maintenance, replacement Lower community impact Construction congestion Less cost and waste Organized by Bahiru Bewket(PhD)
- 9. Green Beyond Longevity ReducedEnergy During Construction Improved Fuel Economy Lighter and Cooler Recycling and Waste Reduction Water Efficiency Sustainable Sites Organized by Bahiru Bewket(PhD)
- 10. Recycling and Reuse Concreteis 100% recyclable Recycled concrete aggregate (RCA) can be used in new concrete Sub base granular fill Recycled Content Recycled Aggregate Fly ash Slag Silica Fume Organized by Bahiru Bewket(PhD)
- 11. SOCIAL Concrete delivers atriple bottom line solution SOCIAL Essential part of construction industry Provides livelihood for employees Create structures providing safe shelter Contributes to aesthetic of built environment Flood and fire protection ENVIRONMENTAL Key enabler of renewable energy technologies Superior performance - Thermal mass - Durability - Sound Insulation Readaptation and reuse of structures Recycling of materials at end of life ECONOMIC Relatively low economic cost vs performance Lowest whole-of-life cost (NPV) in infrastructure Good geographic availability (lower transport costs) Durability lowers maintenance costs people + planet + profit = green Organized by Bahiru Bewket(PhD)
- 12. Composition of sustainableconcrete Societal contribution Cement contribution Concrete production contribution Aggregate contribution Organized by Bahiru Bewket(PhD)
- 13. Cement industry progress CementRoadmap Indicators 2012 2015 2020 2025 2030 2050 Thermal energy consumption per tonne of clinker GJ/tonne 3.9 3.8 3.5-3.7 3.4-3.6 3.3-3.4 3.2 Share of alternative fuel & biomass use (1) 5-10% 10-12% 12-15% 15-20% 23-24% 37% Clinker to cement ratio 77% 76% 74% 73.5% 73% 71% CCS no. of pilot plants no. of demo plants operating no. of commercial plants operating Mt stored 2 0.1 3 2 0.4 6 5-10 10-15 20-35 50-70 100-160 200-400 490-920 Tonne CO2 emissions per tonne cement (2) 0.75 0.66 0.62 0.59 0.56 0.42 3.3GJ/t 7.15% 74% 0.66t CO2e Organized by Bahiru Bewket(PhD)
- 14. Sustainable use ofaggregates COARSE AGGREGATES 3 classes of aggregates Natural Recycled Re-used by-product and Manufactured Description, Applications and Availability Benefits from their use Constraints to wider use – availability, processing energy, mix design considerations, cleanliness of product Relevant specifications Organized by Bahiru Bewket(PhD)
- 15. Sustainable use ofaggregates FINE AGGREGATES / SANDS Extended use of quarry by-product to conserve natural resources Enrolment of specifiers in process to achieve a sustainable outcome Organized by Bahiru Bewket(PhD)
- 16. Brick Sustainable The Competitionseeks integrative solutions for a building using clay masonry units (brick) as a primary material. This competition seeks to explore the potential of brick construction. Design teams are challenged to maximize the physical characteristics of construction in the creation of integrated design solutions utilizing the the material such as thermal mass, porosity, modularity, color, etc. Organized by Bahiru Bewket(PhD)
- 17. Thermal Storage Thermal StorageWall Systems Heat absorbed from sunlight slowly penetrates 10-18 in. brick walls and warms the interior. Less temperature fluctuation than direct gain systems. Performance may be increased by providing vents to induce convection. reduce heat island Organized by Bahiru Bewket(PhD)
- 18. A challenge tothe innovator……… The construction industry is rightfully conservative in delivering solutions to the community What is the place for innovation? Organized by Bahiru Bewket(PhD)
- 19. Innovative ideas fromfuture market trends Residential market Users requirements will change more frequently Accessibility and flexibility improved Increased emphasis of environmental burden of materials Passive design and renewable energy focus Use of building management systems Affordability for an urban and social mix “a dynamic of developer, investors, the construction industry, professional services, industry suppliers:- achieving sustainable development taking into consideration environmental, socio-economic and cultural issues” Infrastructure Life cycle considerations for both construction and continued use Land use and resource constraints Distributed society responding to technology evolution Non-residential market Improved energy efficiency and integration of renewable energies Indoor air quality( including heating/cooling, lighting and acoustics) Adaptability and divisibility of premises to respond to system technologies Retrofitting( add accessories which haven’t at manufacturing time ) and re-use Passive design=takes advantages of the climate to maintain a confortable temperature range in the home Organized by Bahiru Bewket(PhD)
- 20. Alternative binders DRIVERS Environmental Greenhouse andGovernment incentives Technical Durability and less permeable; strength and set control Special properties Binding ability, cheap aggregate Hi Tech applications Economical High material cost, lower production cost, Looking application benefits Availability and control Waste treatment/reduction Binding capacity, low permeability for toxic and nuclear waste Cement production capacity Additional capacity in times of high demand Organized by Bahiru Bewket(PhD)
- 21. Commercial construction casestudy INNOVATION Double skin façade – 42% less energy High strength concrete in columns – more floor space 90% of all steel with 50% recycled content 94% of all construction waste reused 5758 tonnes less CO2 in concrete
- 22. Construction Equipment Traffic delay Transportation Use Rolling resistance Carbonation Lighting Leachate Maintenance Materials phase Construction phase End oflife Equipment Landfilling Recycling/Reuse Transportation Materials Extraction Production Transportati on Materials Extraction Production Transportation Construction Equipment Temporary structures Transportation Use Plug loads Lighting Thermal Mass Routine maintenance End of life Demolition Landfilling Recycling/reuse Transportation ROADING BUILDING Elements to Concrete LCAs Organized by Bahiru Bewket(PhD)
- 23. LCCA determines thefull cost of mutually exclusive construction options, deriving the lowest total lifetime cost. LCCA accounts for future maintenance and operational activities. Life cycle – cost analysis APPLICATIONS compare alternative designs, evaluate payback periods, or, calculate cost effectiveness of environmental improvement strategies. Organized by Bahiru Bewket(PhD)
Editor's Notes
- #11 Climate change is a key challenge of our time. Urgent action must be taken to reduce greenhouse gas emissions in order to avoid likely dangerous effects of climate change. Most of the potential low cost greenhouse gas emissions (carbon) saving opportunities are known to be in the built environment. However, past experience suggests that market failure/ barriers will prevent uptake of these opportunities (even with a price on carbon). The aim of the CRC is to provide government and industry with social, technological and policy tools to overcome identified market barriers preventing adoption of cost effective low carbon products and services, while maintaining industry competitiveness and improving quality of life. The CRC assembles, for the first time, the necessary critical mass and diversity of built environment stakeholders to address this complex multidisciplinary task, and provides government and industry with a vehicle for trialling alternative infrastructure and community engagement solutions. The CRC participants include 26 industry organisations, 16 government agencies and 6 research institutions. Outcomes from the CRC include: Reduced built environment carbon emissions by 10MTCO2-e/yr by 2020; and Adoption of government policies and industry business models that set Australia on a pathway for future deep carbon reductions. The CRC includes three programs of research consistent with major industry recommendations: Integrated Building Systems: This program will develop (i) low-carbon-lifecycle building construction components/ materials, and (ii) building-integrated multipurpose solar products. These outputs target next generation construction practice, where step-change emissions cuts are required. New design tools, rating frameworks and Australian Standards will underpin and stimulate the market for low carbon products and services. Design tools and a solar product will be commercialised in partnership with SMEs. Low Carbon Precincts: This program will develop tools that enable the design of, and stimulate the market for, low carbon infrastructure at 'precinct' scale. This will facilitate property developers and local government partners providing low carbon infrastructure at the development planning point of delivery. An emphasis on research education and training in building information modelling (BIM), and extension to a new precinct scale (PIM) platform, will dramatically improve SME design productivity. Health and productivity co-benefits analysis will demonstrate the increased value and stimulate demand for low carbon precincts. Engaged Communities: This program will focus on understanding and influencing behaviour and purchasing decisions. Policy scenario analysis will quantify the effectiveness of alternative options leading to policy adoption by government partners. New low carbon living strategies that mobilize cultural and social capitals will be demonstrated. CRC research findings will be fully road tested in 'living laboratories' to ensure that results are robust, tangible and appealing. Results will be used to develop community education and training resources including for mass media dissemination.
- #13 with global warming, weather conditions are becoming more extreme more +40C days in summer, with low humidities and high winds all buildings within 1 km of temperate/sub-tropical bushland should be designed as for high- risk areas
- #21 1 Bligh Street is the next generation in high performing sustainable office space, with a 6 Star Green Star - Office Design v2 rating and a number of innovative sustainability strategies that are 'firsts' in the market place. 1 Bligh Street has a 5 star NABERS Energy commitment which is the highest achievable energy rating possible in Australia, and is also aiming to achieve a 6 Star Green Star Office as Built rating in 2011. DEXUS Property Group Chief Executive Officer, Victor Hoog Antink, said: "Every aspect of 1 Bligh Street - from its double skin façade (an Australian high rise first) to the unique, full building height, naturally ventilated atrium - is designed to optimise sustainability and tenant amenity throughout the 28 level development." A new face in town The development's double skin façade system is a major contributor to the 6 Star Green Star rating. This naturally-ventilated glass façade was designed to optimise occupant amenity. Views are maintained, with 70 per cent of the Net Lettable Area (NLA) within eight metres of either the façade or the atrium, while providing optimum daylight entry and solar control. The components of the façade system include a double-glazed inner skin of high-performance glass and an outer skin of clear glass separated by an accessible cavity which is naturally ventilated and contains an automated blind. The unique façade allows 45 per cent of the office NLA to achieve high daylight levels, reducing the need for artificial lighting. This, combined with reduced heat loads, helps keep energy consumption to a minimum, and enables energy performance to achieve the 5 Star NABERS Energy requirements, with a 42 per cent carbon dioxide reduction when compared to a similar-sized conventional office tower. Super cool The design of 1 Bligh Street incorporates an innovative hybrid tri-generation arrangement that uses gas and solar energy to generate cooling, heating and electricity. An array of 500m2 of roof-mounted solar panels provides free cooling for the building, and in combination with the large trigeneration unit, reduces the load on grid power by more than 27 per cent. Minimising materials Green Star rewards building projects that both minimise materials wastage and select environmentally-preferable materials. In 1 Bligh Street, the specially-formulated high-strength concrete used, as well as the design which reduces the number of columns required, has in turn reduced the amount of concrete needed. In addition, 20 per cent of all aggregate used in the concrete is recycled, and around 41 per cent of all cement required for the structure was replaced with industrial waste by-products. ninety per cent of the steel used has a recycled content greater than 50 per cent, and the project team worked to ensure than all timber used is either FSC Certified or re-used from a previous application Grocon Chief Executive Officer, Daniel Grollo, who was an original board member of the Green Building Council of Australia, has said that "the use of unique high-strength concrete with a lower cement content means there is 5,768 tonnes less of carbon dioxide being released into the atmosphere and, to date, we have recycled 37,000 tonnes or 94 per cent of all construction waste produced on the project." Water-wise 1 Bligh Street is the first building to use blackwater recycling in a high-rise office building in Sydney. Waste water is treated via a central blackwater treatment plant and recycled for toilet flushing and make-up water to the cooling towers. This will save approximately 100,000 litres of water a day which, when annualised, is equivalent to an Olympic swimming pool every two weeks. In addition, a 65,000 litre rainwater harvest tank recycles rainwater for irrigation. Water-efficient appliances are used throughout, using 3 star WELS-rated showerheads, 5 star-rated hand wash basin taps and 4 star-rated toilets. All water use is monitored via the building management system. As a result of these systems being implemented, reliance on municipal potable water sources has been reduced by more than 90 per cent. Total Innovation The team behind 1 Bligh Street was awarded five innovation points (out of a possible five) from the GBCA for setting new innovation benchmarks in Australia.These points were awarded for: Naturally-ventilated double skin façade development and the evaluation of improved amenity for the occupants in relation to view, glare and thermal comfort Hybrid trigeneration using gas-fired power generation, absorption chillers and solar cooling to reduce peak and annual energy consumption The tempered environment - applying a different set of comfort criteria to break-out spaces and the main lobby entrance of the building, and maintaining year-round comfort conditions using recycled heat and relief air Full height naturally-ventilated atrium that encourages occupant wellbeing and satisfaction Greatly reduced building embodied energy via the use of cement replacement technologies in highstrength concrete without significantly affecting the construction program and structural climbing cycles. "Achieving five innovation points out of a possible five reflects 1 Bligh Street's position as a truly ground-breaking green building," says the GBCA's Chief Executive, Romilly Madew. "This building will provide a new benchmark for sustainable office space in Australia." ESD initiatives featured in the project Indoor Environment Quality Full height, naturally-ventilated internal atrium Double skin column-free façade system, promoting maximum daylight and views Low VOC paints, sealants, adhesives and carpets are used throughout the building to improve air quality Energy Roof-top solar thermal collectors which inject high-temperature energy into a solar cooling system; provides enough energy to allow 100 per cent more fresh air to be pumped through the building without any additional running costs Low-temperature VAV hybrid with chilled beam within naturally-ventilated spaces High-efficiency lighting Perimeter lighting controlled by automatic photocell control Timed lighting switches with manual override Transport 270 bicycle spaces with accompanying locker and shower facilities Water The first use of blackwater recycling in a high-rise office building in Sydney that will save 100,000 litres of water a day, equivalent to an Olympic swimming pool every two weeks Rainwater recycling for irrigation of plants on rooftop Land Use and Ecology Glazed and naturally-ventilated wintergarden space at ground floor level