Construction Waste Minimisation Design in China: ???????????:

1
Construction Waste Minimisation Design in
China???????????

• through a Comparative study between the UK and
  China

Yi Ying HAO, Jian Kang School of Architecture,
University of Sheffield
2
Introduction

• The UK and China are both confronted with an
  increasing rate of construction(????) and a
  decreasing capacity of landfill (????)at present,
  which calls for construction waste minimisation
  urgently.
• Considerable differences have been found in the
  effort on waste minimisation (?????)as well as on
  construction waste minimisation design
  (?????????)between the UK and China.
• A comparative study was made based on the
  existing survey in the UK. The survey in China
  includes
• Acquaintance of the legislations (????????)
• Implementation of construction waste minimisation
  design (???????????)
• Causes of construction waste (????????)
• Barriers incentives for construction waste
  minimisation design (?????????????????)
• Architects attitudes to construction waste
  (???????????)

Source http//photos.nphoto.net/photos/2007-09/06
/ff80808114c5908e0114d6acb3cd5432.shtml
3
Introduction
UK China
Construction waste (????) 120 million t of construction, demolition and excavation waste is produced by construction industry per annum. More than 25 million t of construction waste is disposed by landfill in the UK every year. By 2020, China will increase 30 billion m2 of construction area, so the amount of potential construction waste will be an amazing number (1500-1800 million t).
Need for reclaimed and recycled materials (????????????) Minimisation of wastes during aggregates production Careful use of aggregates in the process of construction, Appropriate use of aggregates Increased substitution of secondary and recycled materials for primary aggregates. Green Construction Guideline (2007) (??????)encourages the development of new technology, new equipment and new materials in green construction, including the application technology of reclamation of the construction waste in envelop materials.
Information sources for construction waste minimisation design (??????????????) Legislations on waste disposal Handbooks on construction waste minimization Website, competition, training course for waste minimization design Legislations on waste disposal Information of material recycling little information supports online
Models for construction waste evaluation (????????) BREEAM, SPeAR, LCA In 2007, Green Building Assessment (??????) the first book in China systematically is published introducing the U.S. LEED, U.K. BREEAM, Japan CASBEE, GreenCalc, Taiwan Green Building, Australian NABERS.
Role of construction waste minimisation design (????????????) Design for Reuse and Recovery Design for Off Site Construction Design for Materials Optimisation Design for Waste Efficient Procurement and Design for Deconstruction and Flexibility. when it comes to construction waste minimisation, waste management and technology supports seem to be emphasized most frequently. The views on designing out waste are limited.
4
Method

• Respondents
• The architects in Grade A Architecture Design
  Institutes in provincial capitals (??????????)
• The ranking of these institutions in China is
  mainly based on the registered capital, the scale
  of projects and
• the number of registered architects.
• Questions
• The questionnaire totally includes 20 questions,
  with seven same questions as those of the survey
  in the UK.
• Single-choice questions, multiple-choice
  questions, rating scales and open questions in
  the questionnaire.
• Questionnaire distribution and return
• The use of questionnaire web page
• The address of the web page was sent to 80
  architects, with the response rate of 76.
• Data Analysis
• Statistical Package for Social Science (SPSS)
• Approaches of analyzing
• One Sampling t-Test (comparing means)
• Independent samples t- Test (compare variables
• between two group)
• Tabulated open-ended questions (collect and
• analyze individual suggestions)

5
Method

• Working age
• (????)
• Education level
• (????)
• Workload
• (???)

6
Questionnaire Sample
7
RESULTS Chinese architects
Background Information

• Acquaintance with relevant legislations
  (??????????)
• The respondents do not know the legislations.
• lt PRC Law of Solid Waste Pollution
  Prevention and Control gt ??????????????????
  34.4
• lt Law of Urban Solid Waste Disposal
  gt????????? 37.7
• ltGreen Construction Guidelinegt??????
  39
• ltUrban Construction Waste Management
  Regulationsgt?????????? 37.7
• Acquaintances of the concept of construction
  waste minimisation design (?????????????????)
• Over 60 of respondents reported that
  they never heard the concept of construction
  waste minimisation by design, therefore, most of
  them have not had a clear and scientific idea on
  what is construction waste minimisation by
  design.
• Courses and projects relevant to construction
  waste minimisation design in college
  (???????????????????)
• More than 85 said that they never
  attended any courses on designing out waste.
  Meanwhile, nearly 80 acknowledged that they
  never did the projects which were concerned with
  construction waste minimisation design in college.

8
Green Housing Rating Systems
RESULTS Chinese architects
The usage of Green Housing Rating Systems
(????????) can reflect the Chinese architects
concern with sustainable design and construction
waste minimisation.
Employ Green Housing Rating Systems in projects
Never over 60 A little
nearly 20 Often
6.6.
9
Importance of construction waste minimisation
design
RESULTS Chinese architects
Most of the Chinese architects acknowledge the
importance of designing out waste.

• Very important
  over 35
• Extremely important about
  22
• Not important at all
  0

10
Views on the importance of construction waste
minimisation design
RESULTS Chinese architects
???????????,???????????????????,????????????,????
???,????????????????

• extremely important and very important
• (1) Beneficial to saving sources (??)and energy
  (??)
• (2) Reducing waste (??)and pollution (??)and
  protecting environment.
• (3) Considered as a challenge (??)as well as a
  responsibility (??)
• (4) The problem of waste would be more serious in
  the foreseeable future
• moderately important
• (1) The current economic and management level
  (???????)could not support it.
• (2) No requirement from clients (??)and
  legislation(??),
• (3) Little knowledge (??)of it
• (4) A lack of design time (????).
• slightly important
• (1) Mainly produced during the process of
  construction(????), and not related to design
  strategies(????)
• (2) Inevitable due to big design changes
• (3) Considered as a stunt (??)
• (4) Complicated and difficult to put into
  practice, while less benefit
• (5)The public have not pay attention to it.
  (?????)

????????,???????,????????????,????????,?????,????
??????
???,????????,???????????,?????
11
Information sources for waste minimisation
RESULTS comparison between the UK and China
what is the problem?
UK (Source Osmani Glass, 2007)
China

• More than 50 of information of waste
  minimisation came from media and articles
  (??/??), but the information support from
  training courses (????) and professional bodies
  was very limited, each occupying 3.3.
• The architects in the UK had more information
  channels, including professional bodies (????),
  personal research (????).
• The fact that the information sources are
  relatively inadequate (???)can reflect the
  current situation that the consciousness of the
  importance of information for designing out
  waste(?????????????) is still not enough in the
  whole society of China.

12
Waste minimisation design barriers
RESULTS comparison between the UK and China
what is the problem?
(b) China
(a) UK (Source Osmani Glass, 2007)
Barriers (China) Responses Responses
Barriers (China) Mean rating Ranking
Lack of interest from clients 4.12 1
Poorly defined individual responsibilities 3.76 2
Lack of training 3.75 3
Waste accepted as inevitable 3.59 4
1. Not a barrier 2. Insignificant barrier 3. Minor barrier 4. Significant barrier 5. Major barrier. 1. Not a barrier 2. Insignificant barrier 3. Minor barrier 4. Significant barrier 5. Major barrier. 1. Not a barrier 2. Insignificant barrier 3. Minor barrier 4. Significant barrier 5. Major barrier.
Barriers (UK) Responses Responses
Barriers (UK) Mean rating Ranking
Lack of interest from clients 3.88 1
Waste accepted as inevitable 3.83 2
Poorly defined individual responsibilities 3.80 3
Lack of training 3.70 4

• Lack of interest from clients (??????)is also
  the top significant waste minimisation barrier in
  China, followed by poorly defined individual
  responsibility (????????)and lack of
  training(????).

Nearly 70 said that clients never called for
waste minimisation design, while only 3.3
declared clients often asked for it.
13
Causes of construction waste
RESULTS comparison between the UK and China
what is the problem?
Design stages
Last minute change due to the clients
requirement (????????????) 4.15 Design changes
(????) 3.93 Detailing errors
(????) 3.66 The difference
between these mean ratings of the listed causes
is slight. The mean ratings are relatively high.
Site operations
Off-cut from cutting materials (??????????)
4.31 Unused materials and products (?????????)
4.28 waste from application processes
(??????????) 4.10 The mean ratings of
each cause of waste during site operations are
relatively higher than that during design stages,
the same as the results from the architects in
the UK.
14
Waste minimisation design incentives
RESULTS comparison between the UK and China
what can we do?
China
UK (Source Osmani Glass, 2007)
Incentives (China) Responses Responses
Incentives (China) Mean rating Ranking
Legislation 4.40 1
Financial rewards 4.30 2
Waste management policy in place 3.74 3
Training 3.35 4
1. Not an incentive 2. Insignificant incentive 3. Minor incentive 4. Significant incentive 5. Major incentive. 1. Not an incentive 2. Insignificant incentive 3. Minor incentive 4. Significant incentive 5. Major incentive. 1. Not an incentive 2. Insignificant incentive 3. Minor incentive 4. Significant incentive 5. Major incentive.
Incentives (UK) Responses Responses
Incentives (UK) Mean rating Ranking
Legislation 4.55 1
Financial rewards 4.55 1
Waste management policy in place 3.93 2
Training 3.90 3

• Chinese architects also believed legislation
  (????) was the key waste minimisation incentive,
  followed by financial rewards, while training
  (??) was the least significant measure.
• An allowance (??) for recycled construction
  products (??????),
• Tax credit (?????) for the construction
  companies use recycled products (??????),
• a higher tax (????) on the construction
  companies use original products (??????) to
  encourage reducing(??), reusing (???) and
  recycling (????) of waste materials.

15
Waste minimisation design strategies
RESULTS comparison between the UK and Chinawhat
can we do?
China
Waste minimisation design strategies (China) Architects responses Architects responses Architects responses Architects responses Architects responses Architects responses Architects responses
Waste minimisation design strategies (China) Percentage Percentage Percentage Percentage Percentage Mean rating Ranking
Waste minimisation design strategies (China) 1 2 3 4 5
Feasibility study of waste estimation 50.8 27.9 11.5 9.8 0 1.80 8
Designing for deconstruction 36.1 27.9 27.9 8.2 0 2.08 7
Use of standard dimensions and units 14.8 13.1 36.1 26.2 9.8 3.03 1
Use of prefabricated units 16.4 19.7 39.3 19.7 4.9 2.77 4
Specifying reclaimed/recycled materials 16.4 42.6 26.2 11.5 3.3 2.43 5
Use of standard materials to avoid Cutting 14.8 16.4 39.3 21.3 8.2 2.92 2
Avoidance of late variations in design 19.7 19.7 31.2 23.0 6.6 2.78 3
Guidance for hazardous waste Management 32.8 32.8 18.0 11.5 4.9 2.23 6
1. Never been used 2. Rarely used 3. Used in some projects 4. Used in most projects 5. Used in all project. 1. Never been used 2. Rarely used 3. Used in some projects 4. Used in most projects 5. Used in all project. 1. Never been used 2. Rarely used 3. Used in some projects 4. Used in most projects 5. Used in all project. 1. Never been used 2. Rarely used 3. Used in some projects 4. Used in most projects 5. Used in all project. 1. Never been used 2. Rarely used 3. Used in some projects 4. Used in most projects 5. Used in all project. 1. Never been used 2. Rarely used 3. Used in some projects 4. Used in most projects 5. Used in all project. 1. Never been used 2. Rarely used 3. Used in some projects 4. Used in most projects 5. Used in all project. 1. Never been used 2. Rarely used 3. Used in some projects 4. Used in most projects 5. Used in all project.

• Generally the waste minimisation design
  strategies are not very often used in projects in
  China. The difference between two countries are
  not significant.
• F D (?????????)(?????)strategies are
  the least popular in projects in China, which is
  the same as in the UK.

16
Waste minimisation design
RESULTS comparison between the UK and Chinawhat
can we do?
Implementation of construction waste minimisation
design

• Old building
  reconstruction (?????)is the most usual in
  practical projects, and it is considered as the
  most effective construction cost-saving method.
• The use of recycled materials(??????) is
  rarely put in practice,
• but it is considered as the second effective
  method.

design types(China) Responses Responses
design types(China) Mean rating Ranking
Old building reconstruction 2.50 1
Flexible design 2.10 2
Reclamation of construction materials 2.07 3
Use of recycled materials (e.g. recycled concrete recycled bricks) 2.02 4
1. Never been used 2.Rarely used 3.Used in some projects 4.Used in most projects 5.Used in all projects . 1. Never been used 2.Rarely used 3.Used in some projects 4.Used in most projects 5.Used in all projects . 1. Never been used 2.Rarely used 3.Used in some projects 4.Used in most projects 5.Used in all projects .
Cost-saving of construction waste minimisation
design
Design types(China) Responses Responses
Design types(China) Mean rating Ranking
Old building reconstruction 3.37 1
Use of recycled materials (e.g. recycled concrete recycled bricks) 3.29 2
Flexible design 3.20 3
Reclamation of construction materials 2.67 4
1. Not at all 2.Slightly 3.Moderately 4.Very 5.Extremely. 1. Not at all 2.Slightly 3.Moderately 4.Very 5.Extremely. 1. Not at all 2.Slightly 3.Moderately 4.Very 5.Extremely.
17
Waste minimisation management means
RESULTS comparison between the UK and Chinawhat
can we do?

• In China, more than 60 of respondents
  acknowledged that they never did anything in
  waste minimisation management means. The
  respondents who never did anything for these
  responsibilities in China were twice (??)that in
  the UK.
• The architects in the UK have more means in
  construction waste minimisation.

18
Conclusion

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