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Design of Deconstruction

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Design of Deconstruction Powered By Docstoc
					COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler




    Demolition and recycling of demolition rubble after deconstruction:
                       Design for Deconstruction

                                   Dr.-Ing. Paul Kamrath, Paul Kamrath Deconstruction, Germany

                                             Dr.-Ing. Oliver Hechler, ArcelorMittal, Luxembourg




                                                                                        Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Overview


 Problem defining                                        The lifetime of buildings is limited by economic
                                                         questions, change of architectural needs, urban
                                                         redevelopement, reuse of area. At the end of lifetime,
                                                         buildings have to be deconstructed.
                                                         How can we keep the waste disposal rate little?




Goal                                                     Waste management in reference to demolition
                                                         techniques.
                                                         How can we get high recycling rates and what limitations
                                                         do we have due to contaminations?

                                                                                          Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Agenda

                                                        General information & statistics         

                                                         Deconstruction concepts
                                                         Demolition techniques
                                                         Contaminations
                                                         On-site vs. Off-site recycling
                                                         Design for Deconstruction
                                                         Conclusions




                                                                                     Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


General information & statistics


           Construction & demolition waste in the EU:                             450 Mio tons
           Generated C&D waste (w/o earth materials):                             180 Mio tons
           Quote of reuse / recycling:                                              28 % (EU-15)
           Quote of landfilling:                                                    72 % (EU-15)


           Variety of recycling rates for some EU-15 countries (1999):

           UK:                                                                       45 %
           Spain:                                                                    <5 %
           Netherlands:                                                              90 %




                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


General information & statistics


           Since construction and demolition waste represent a large part of the total waste
           generation and have a high potential for recycling, it is important to know the
           composition of this kind of waste. The OECD/Eurostat joint questionnaire asks for
           information on waste from the construction sector and for the total quantity of the
           relevant waste stream.


                                                                                         Construction phase


                                                                                         Deconstruction phase

                                                                                         Non-mineral, non-
                                                                                         metal, contaminated
                                                                                         materials


                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


General information & statistics


          In the case of building demolition waste, KWTBau (2005) determined that from the 52.1
          Mt corresponding to this item, 35.7 Mt were recycled representing a 68.5%
          recyclingrate. 7.0 Mt (13.4%) were used in mining installations and 3.8 Mt (7.3%) were
          directly used by public authorities. 1.6 Mt (3.1%) were used for landfill construction and
          4.0 Mt were landfilled.
                                       Composition of C&D Waste in Germany (2005)

                                        Construction
                                                                               Excavated
                                         site waste
                                                                                material
                                             4,30
                                                                                140,90




                                  Building
                                 demolition
                                                              Road
                                waste 52,10
                                                            demolition
                                                           waste 16,60

                                                                                   Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Deconstruction concepts


          Two phase deconstruction concept without recycling (outdated):




         No recycling !                                                        No separation, no decontamination !


                                                                                     Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Deconstruction concepts


          Four phase deconstruction concept with separation and recycling:
                                                                    Mainly contaminated debris
                                                                                         needs to be disposed




                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Deconstruction concepts


          The four phases concept keeps the amount of mixed waste little:
          + Decontamination before deconstruction of general materials
          + Separation of debris fractions at all stages
          + Possibility to reuse / recycle most waste
          - Higher costs for separation / decontamination
          - More sophisticated processes


          But:
          Even the best deconstruction concept is limited to regulations by law. The possibility to
          recycle concrete / bricks still depends on the quality of the raw material (chemical
          analysis).


                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Demolition techniques


          The demolition industry has undergone major transformation within the last 20 years.
          More recently, mechanized processes with specialized equipments replacing manual
          labour.

          Main techniques (Usage quota in Germany, 2002):
          Deconstruction by excavators with shears etc.:                       82%
          Exploding:                                                           4%
          Deconstruction with wrecking balls:                                  3%
          Other machines:                                                      3%
          Precussion, abrasion, heating etc.:                                  3%
          Robots:                                                              0,3%
          Other:                                                               1,7%

                                                                                      Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Demolition techniques


          Deconstruction by excavators with shears etc.:                              82%

                                                                               Wrecking balls:
                                                                               + Very effective
                                                                               - Uncontrolled demolition
                                                                               - No separation during deconstruction


                                                                               A good choice, when no neighbouring
                                                                               buildings surround the site. Very dangerous.




                                                                                                  Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Demolition techniques


          Deconstruction by excavators with shears etc.:                              82%

                                                                               Rotational hydraulic shears:
                                                                               - Less effective
                                                                               + Highly controlled deconstruction
                                                                               + Separation during deconstruction
                                                                               + less noise emission


                                                                                In most cases the best way to deconstruct
                                                                               any building type.




                                                                                                  Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Demolition techniques


          Deconstruction by excavators with shears etc.:                              82%

                                                                               Pulling / Pushing:
                                                                               + Effective on brick-walls (no concrete)
                                                                               - Limited height, high distance to building
                                                                               - Only single parts may pulled/pushed
                                                                               + less noise emission


                                                                                Special pulling arms extend the maximum
                                                                               reachable height.




                                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Demolition techniques


          Deconstruction by excavators with shears etc.:                              82%

                                                                               Grabbing:
                                                                               + Effective on low-weight-structures
                                                                               - Limited height
                                                                               - Best separation possibility
                                                                               + less noise emission


                                                                                Especially older roof constructions can
                                                                               easily be deconstructed. If the need, to
                                                                               separate already during the deconstruction
                                                                               process is given (contamination, tar), very
                                                                               effective.

                                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Demolition techniques


          Deconstruction by excavators with shears etc.:                              82%

                                                                               Hydraulic breaker
                                                                               + Only applicable instrument on thick structures
                                                                               - No separation possibility
                                                                               + high noise emission


                                                                                Usually used, if working with shears is not
                                                                               possible.




                                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Demolition techniques


          Deconstruction by excavators with shears etc.:                              82%

                                                                               Longfront excavators:
                                                                               + Working height up to 50m
                                                                               + Alternative method to avoid explodings


                                                                               With longfront machines, mostly all common
                                                                               tools used with excavators may used.




                                                                                              Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Contaminations


          Why can we not reach recyclingrates of 100%?
          Today we know, that some products used up to the 1980„s are dangerous (asbestos,
          older glass wool products, PAH – tar). The disposal of dangerous products is
          monitored. Reuse or recycling mostly is not allowed.

          As a result of the building„s usage
          over many years, we find
          contaminations which pollute our
          environment (e.g. concrete covered
          with oil or fuel). Polluted materials
          have to put on special disposals.
          In General: Two kinds of pollution:
          1 Danger for health
          2 Danger for environment

                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Contaminations


          In Germany, the mineral debris needs to be chemically analyzed. In accordance to the
          rate of pollutions, the material is categorized. Main parameters are heavy metals,
          pollutions due to usage, PH-value, conductivity, chlorides and sulfates.




                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


On-site recycling vs. Off-site recycling


Question                                            When is it worth to recycle mineral debris on-site?
                                                    By mass the mineral debris is the most important material arising
                                                    by deconstruction work. Recycling this material to gravel for street
                                                    constructions is evident, to improve recycling rates.


 Two possibilities                              - Driving the separated but not recycled material to an off-site
                                                  recycling plant and pay a feed for the temporary disposion and
                                                  outsourced recycling work.
                                                - Bringing a mobile recycling-plant to the site and recycle the
                                                  separated concrete / brick material on-site.
                                                    For environmental reasons, the result will be the same: Most
                                                    mineral debris can be recycled…



                                                                                        Demolition and recycling of demolition rubble after deconstruction
 COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


On-site recycling vs. Off-site recycling


The difference                                       On-site recycling is only practicable, if most of the recycled gravel
                                                     can be used on-site after. If the mass-balance does not fit, the extra
                                                     material is often landfilled and not reused!
                                                     Higher costs, because one pays for the on-site recycling and the
                                                     transport.

Economic calculation                                  C fixed  M md  Cload  M md  Ctrans
                                                      Cfixed:            General costs of a mobile recycling machine
                                                      Cload:             Costs to recycle one ton of debris
                                                      Ctrans:            Costs for one ton of debris brought to off-site plant
                                                      Mmd:               Total mass of concrete [tons]


                                                      Break-even point is roughly about 1.000tons
                                                                                                   Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Design for Deconstruction


Remember:                                          Only 1,7% of all deconstruction work is not done by excavators,
                                                   machines in general or explosion – Thus by damaging

What is „Design for Deconstruction“?:
                            The result of recycling of concrete is a new product (gravel) as
                            an alternative to natural gravel. The recyclingprocess
                            downgrades our waste to something, what is still usable.
                                                   Especially metals and steel are not downgradet. Remelting for
                                                   new products (e.g. cars) produces a new product of the same
                                                   quality (closed loop).
                                                   Why not use parts of the former building as they are?
                                                    Only applicable for structures of steel and wood. Not
                                                   applicable for concrete structures (weight, effort) but also for
                                                   some „old“ building materials.


                                                                                        Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Design for Deconstruction


Example of reused materials:




                                                                 Production of new cobble stone is expensive and not
                                                                 common. Modern roads / places are not made of cobble
                                                                 stone.
                                                                 But: Old cobble stones are usefull for historic places.

                                                                                              Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Design for Deconstruction


Example of reused structures: Economical sustainability
                              Easy dismantling and Reuse of structures : Second life




 Munich Airport Parking built in 1972,                                         Parking du Stade in Luxemburg
 rebuilt in 2 parts: 1995 in Neuss and 1996
 in Gross-Gerau



                                                                                          Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Design for Deconstruction


Example of reused structures: Economical sustainability
                              Reuse of structures : Second life




 1958: Brussel´s World´s Fair;
 1959: “Zoo-Brücke” in Duisburg;
 2000: Bridge further south the A3


                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Design for Deconstruction


Example of reused structures: Economical sustainability
                              Reuse of structures : Second life




 1958: Brussel                                                                 1958: Brussel
 2008: Prague                                                                  2008: Brendoonk



                                                                                                 Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Design for Deconstruction


Example of reused structures: Economical sustainability
                              Flexibility and easy renovation




 Luxembourg Chambre of Commerce
 The same building at the same place – First two phases were done (decontamination and
 core-removal). The structure (concrete, steel) was kept.

                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler


Conclusions


          The recyclingrate is not at its optimal level:
          - Quote of recycling in EU-15 is only about 28%
          - Two-phase deconstruction concepts tend to produce a lot of landfilling.
          - Four-phase deconstruction concepts are more sophisticated and produce less disposal.
          - Deconstruction is mainly done with excavators (82%)
          - We can not reach recyclingrates of 100% - due to possible contaminations.
          - There are possibilities to reuse materials as well as parts of the structure.

Future problems

          The rate of non-recyclable materials is arising! Todays buildings make use of more thermal
          insulation (glas wool, polysterene), more hard plaster, more leight-weight materials with
          little possibilities today (prevention, minimization).
                                                                               Demolition and recycling of demolition rubble after deconstruction
COST25, Izmir, 24.5.2010 & 25.5.2010   Dr. Paul Kamrath & Dr. Oliver Hechler




                                             Thank you very much for your attention.
                                       pk@paul-kamrath.de - www.paul-kamrath.de




                                                                               Demolition and recycling of demolition rubble after deconstruction

				
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