structure engineers and green building

Structural engineer and green-building

Table of Content

• Why should we built Sustainable Buildings?• Does building skeleton affect the building sustainability?• Building structure materials.• Comparison on the three building structure materials, upon

LEED rating system.• Conclusion.

• Why should we built Sustainable Buildings?• Dose building skeleton affect the building sustainability?• Building structure materials used.• Comparison on the three building structure materials, upon LEED rating

system.• Conclusion.

Why should we built Sustainable Buildings?

The consumer sectors responsible for the Global Warming are ranked as:

•Buildings (48%)

• Transportation• Industry

*Energy Information Administration 2006. Emission of green house gases in the United States

Why should we built Sustainable Buildings?

The consumer sectors are ranked as:

EPA estimates that if the energy efficiency of commercial and industrial building improved by 10%, the resulting green house gas reduction would be equivalent to taking about 30million vehicles off the road.

*Energy Information Administration 2006. Emission of green house gases in the United States

• Why should we built Sustainable Buildings?

• Dose building skeleton affect the building sustainability?

• Building structure materials used.• Comparison on the three building structure materials, upon LEED rating


• The structure system cost in a building is in the range of 10% - 20% of total project cost.

• The structure engineer is vital for numerous green structures including: green roof, mass transit, wind turbines, and water run-off retention/containment structure.

• Consequently, the role of the structural engineer in green building is that of an interactive green team member.

Dose building skeleton affect the building sustainability?

Structural engineering is an integral part of green building design on number of fronts:

• Recyclability and reusability of materials and systems.

• The choice of locally available materials and resources.

• Resourceful use or efficiency of structural system.

• Provision for future adaptability of the buildings• Numerous green building design strategies can have direct

impact on structural design of the building.

Dose building skeleton affect the building sustainability?

• Why should we built Sustainable Buildings?• Dose building skeleton affect the building sustainability?

• Building structure materials used.• Comparison on the three building structure materials, upon LEED rating


Concrete:• Use of slag from steel mills and fly ash

in concrete mixes reduces CO2 emissions, make it stronger and more resistant to corrosion.

• Another sustainable approach when using concrete is to include recycled aggregate.

Building structure materials used.

Steel:• Steel is the most recycled material

used in modern building construction.

• In addition to the recyclability and percent recycled content of steel, it’s deconstructability can be considered when evaluating it’s sustainability.

• Recycled steel only consumes one quarter the energy it takes to produce virgin steel.


Wood:• The three primary sustainable areas

use of wood are: efficient framing, alternative products, and sustainable material suppliers.


• Why should we built Sustainable Buildings?• Dose building skeleton affect the building sustainability?• Building structure materials used.

• Comparison on the three building structure materials, upon LEED rating system.

• Conclusion.

A key tenet of sustainable design is:

• The holistic or integrated design approach.

• Coordinating the architectural, structural, and mechanical designs early in the schematic design

• Deciding which beneficial interactions are essential for project success.

Comparison on the three building structure materials, upon LEED rating system.

How could we evaluate the three structural materials effect, based on the integrated Design?


LEED Category Credit or Prerequisite PointsAvailable

Sustainable Sites Credit 5.1: Site Development, Protect or Restore Habitat 1Sustainable Sites Credit 5.2: Site Development, Maximize Open Space 1Sustainable Sites Credit 7.1: Heat Island Effect, Non-Roof 1Energy and Atmosphere

Prerequisite 2: Minimum Energy Performance ---

Energy and Atmosphere

Credit 1 : Optimize Energy Performance 1 – 19

Materials and Resources

Credit 1 : Building Reuse, Maintain 55%, 75%, 95% of Existing Shell 1 – 3


Credit 2.1: Construction Waste Management, divert 50% by weight or volume 1


Credit 2.2: Construction Waste Management, divert 75% by weight or volume 1


Credit 4.1: Recycled Content, the post-consumer recycled content plus one-half of the preconsumer content constitutes at least 10% (based on cost) of the total value of the materials in the project

1



1


Credit 5.1: Local/Regional Materials, Use a minimum of 10% (based on cost) of the total materials value

1



1

Indoor EnvironmentalQuality

Credit 3.1: Construction Indoor Air Quality Management Plan, During Construction 1

LEED (Leadership in Energy and Environmental Design) In LEED rating, structure engineers could affect these credits:


Credit or Prerequisite Concrete

Cast -in situ

Concrete Pre-cast

Steel Wood

Credit 5.1: Site Development, Protect or Restore Habitat * * *Credit 5.2: Site Development, Maximize Open Space * *Credit 7.1: Heat Island Effect, Non-Roof * * *Prerequisite 2: Minimum Energy Performance *Credit 1 : Optimize Energy Performance *Credit 1 : Building Reuse, Maintain 55%, 75%, 95% of Existing Shell * * * *Credit 2.1: Construction Waste Management, divert 50% by weight or volume * * * *Credit 2.2: Construction Waste Management, divert 75% by weight or volume * * *Credit 4.1: Recycled Content, the post-consumer recycled content plus one-half of the preconsumer content constitutes at least 10% (based on cost) of the total value of the materials in the project

* * *


* * *


* * *


* * *

Credit 3.1: Construction Indoor Air Quality Management Plan, During Construction

*

LEED (Leadership in Energy and Environmental Design) In LEED rating, structure engineers could affect these credits:


Credit 5.1: Site Development, Protect or Restore Habitat: The requirements are met by limiting site disturbance. Since precast concrete sound wall systems are manufactured off site and delivered on demand, there is a significant reduction in truck traffic, dust, noise and debris from formwork, precast concrete structures, and manhole can be used to help obtain this point.


Credit 5.2: Site Development, Maximize Open Space: The intent of this credit is to provide a high ratio of open space to development footprint. The requirements are met by limiting the size of the development footprint, specifically by exceeding the local zoning’s open space requirement. Pre-cast, pre-stressed concrete skeleton can be used to help obtain this point.


Credit 7.1: Heat Island Effect, Non-Roof: The intent of this credit is to reduce heat islands’ to minimize impacts on microclimates and human and wildlife habitats. Pre-cast concrete with SRI of at least 29 used in the hardscape, or in the open-grid pavements, can be used to help obtain this point.


Prerequisite 2: Minimum Energy Performance: All buildings must comply with certain sections on building energy efficiency and performance as required by the ANSI/ ASHRAE/IESNA 90.1-2007. Insulating to meet or exceed the requirements of the standard is generally a wise business choice. Pre-cast sandwich panel walls, can be used to help obtain this point.


Credit1: Building Reuse, Maintain 55%, 75%, 95% of Existing Shell: Precast concrete panels can be reused when buildings are expanded. Concrete pieces from demolished structures also can be reused in other applications. Because the precast process is self-contained, finishing materials are reused, while concrete steel forms have practically unlimited service lives.


Credit 2.1: Construction Waste Management, divert 50%, 75% by weight or volume: Precast concrete can be designed to optimize or lessen the amount of concrete used. In the plant, precast concrete generates low amounts of waste, and the waste generated has low toxicity.


Credit 4 : Recycled Content: In precast concrete, Industrial wastes such as slag cement and silica fume can be incorporated into the mix, reducing the amount of cement, which in turn reduces CO2 emissions.


Credit5.1: Local/Regional Materials: The use of local materials reduces the transportation needs for heavy building materials, along with the associated energy and emissions. Most precast concrete plants are within 200 miles of a building site. The cement, aggregates and reinforcing steel used to fabricate precast concrete components, are usually obtained or extracted from sources within 200 miles.


Credit 3.1: Construction Indoor Air Quality Management Plan, During Construction:Concrete contains low to negligible Volatile Organic Compounds (VOCs). These compounds degrade indoor air quality when they off-gas from manufactured wood products such as laminate, particleboard, hardboard siding and treated wood. Concrete is not damaged by moisture and does not provide nutrients for mold growth.


Credit ID: Innovative in design:Pre-cast concrete applications, could contribute in implementing new intelligent solutions. Rising the performance of HVAC and heating systems, indoor air quality, or pollution prevention.


Geothermal piping:Embedding geothermal piping into structural piles, reducing additional boreholes. The heat energy is absorbed by piping and used for heating.


Hollow core slab ventilation:Hollow core slabs voids, could use for the Stack Effect –pull out the hot air in the night time, with cool air from out side-. And could used with installation of Radiant heat tube. This saves material and reduce heating load.


Photocatalytic cement:Photocatalytic concrete decomposing

the harmful molecules in the vicinity by an oxidation reaction. Thus, fewer harmful chemicals and more pure clean air is available.

Pre-cast concrete is ideal system for using this type of finishing.


• Why should we built Sustainable Buildings?• Dose building skeleton affect the building sustainability?• Building structure materials used.• Comparison on the three building structure materials, upon LEED rating

system.

• Conclusion.

Reduce, Reuse, Recycle• Reduce the amount of material

used and the toxicity of waste material.

• Always search for the integrated solution

Conclusion

Thank You