Construction and Demolition Waste

Reported by:Leandro Michael C. de los Santos, Jr.

Construction and Demolition Waste

TOPIC OUTLINE• Definition of C&D and Key Terms• Typical C&D Wastes• Percentage of C&D Wastes Generated• C&D Waste Generation in the Life Cycle Phases of Construction• C&D Waste Management Approach• Environmental Impacts• Obstacles to C&D Waste Diversion• Studies conducted related to C&D• C&D Patent

Definition of C&D Waste

“Waste material that is produced in the process of construction, renovation, or demolition of structures. Structures include buildings of all types (both residential and non-residential) as well as roads and bridges. Components of C&D debris typically include concrete, asphalt, wood, metals, gypsum wallboard and roofing”.-EPA

Key Terms

• Construction waste- generated throughout the construction process such as during site clearance, material use, material damage, excess procurement & human error (Mahayuddin, et.al,2013)

• Demolition waste- waste generated while in the process of demolition structures (Yeheyis et.al, 2012)- waste debris from destruction of a construction (Ponnada et.al, 2015)

• Deconstruction- the taking apart of an existing building so that materials can be re-used elsewhere

Typical C&D Wastes

• Asphalt, Asphalt Shingles

• Carpet

• Carpet padding

• Clean wood/pallets

• Concrete

• Corrugated cardboard

Typical C&D Wastes

• Gypsum (drywall)

• Land clearing debris

• Scrap metal

• Salvage

Typical C&D Wastes in the Philippines

• Ganiron, 2015- asphalt - polystyrene- concrete - porcelain- dirt - corrugated cardboard- metal - carpet- wood - roofing shingles- brick- glass- gypsum- plastic

Source: M. Yeheyis et.al, 2013

Source: Purdy & Sabugal, 1999

Data on Landfill Generation in CDO

Source: City Local Environment & Natural Resources & City Planning & Development Office

• Construction activities consume 32% of the world’s resources including 12% of water & 40% of energy (Yeheyis et.al, 2012)

Source: Kozlova, et.al.2015

C & D Waste Management Approach

Source: M. Yeheyis et.al, 2013

Environmental Impacts

• Landfill leaks (plasterboard release H2S)• C & D makes municipal waste heavy• Degrade the quality of municipal waste & makes it

difficult for further treatment like composting• 10-20% finds its way into surface drains, choking them• Other toxic elements such as lead, asbestos &

radioactive materials that can leak and pollute the water bodies

• Air pollution

Obstacles to C & D waste diversion

• It is relatively a new practice• Limited recycling markets due to local availability of

equipment• Limited market awareness• Perceived to be more costly• Perceived as requiring more space• Availability of technical knowledge & expertise

Source: C & D Waste Management- Chapter 2

Studies conducted related to C & D

• Mahayuddin et.al, 2013- Quantification of Waste in Conventional Construction

Studies conducted related to C & D

M. Yeheyis, et.al, 2013- Lifecycle analysis approach on C & D

Recycling Concrete Debris

T. Ganiron, 2015- Recycling Concrete Debris from C & D Waste

Recycling & Re-Use of C & D

• Concrete & bricks- can be used as sub-bases in pavement such as roads & non-structural applications, backfill

• Asphalt- to be re-used as recycled asphalt pavement (RAP)

• Metals- recycled back to steel mills (10% gets reused), also used for shoring projects (Gorgolewski, 2006)

• Timber- can be used as infrastructure timber such as power holes and railway sleepers, landscaping, high-market value for the re-use of quality hardwood timber

• Plastics- can be recycles to various products

Source: Australian Government- Dept. of Sustainability, Environment, Water, Population & Communities

Recycling & Re-Use of C & D

• Plasterboards- mostly diverted at landfills as it is not readily separated from mixed loads, plasterboard manufacturers also support the recovery of clean products from construction sites for recycling purposes

• Rock & excavation stones- also used in sub-base pavement

• Sand and soil- can be re-used on site which requires treatment

Source: Australian Government- Dept. of Sustainability, Environment, Water, Population & Communities

C & D Patent

Source: Patent Application Pub.Patent #: US 20090188844A1

C & D Patent

Source: Patent Application Pub.Patent #: US 20090188844A1

Source: Patent Application Pub.Patent #: US 20090188844A1

C & D Patent

Conclusion

• Materials & components from demolished buildings are being reused for new construction works as well as renovation projects.

• In developing countries most of the demolition rubble is dumped, the developed world has now started to recycle it into aggregate for non-structural concrete.

• It is hoped that recycling waste material for use in the building will cut down costs of producing new raw materials thereby reducing consumption of natural resources like energy & reduces usage of landfills.