Construction Technology 3 D39 TA

Transcription

1 Construction Technology 3 D39 TA Revision Dr Mohamed Abdel-Wahab Edwin Chadwick Building, Room 1.16 m.abdel-wahab@hw.ac.uk

2 Week Topic 1 Introduction to the module Part I: On-site construction 2 Topic 1: Foundations for framed buildings 3 Topic 2: Basement construction 4 Topic 3: Structural frames in buildings 5 Topic 4: Advanced cladding 6 Topic 5: Long span roof construction Part II: Off-site construction 7 Topic 6: An overview of offsite construction 8 Topic 7: Case Studies, practical issues & factory production 9 Tutorial week and feedback Part III: Low carbon construction 10 Topic 8: An overview of low carbon construction 11 Topic 9: Low Carbon Technologies (Guest Lecturer) 12 Revision

3 A thorough site investigation is paramount before commencing construction work. 1. Site inspection 2. Desk study

4 Detailed knowledge of the nature and variability of the sub-soil is necessary

5 Boreholes

6 Soil characteristics and type of foundation

7 Pile foundations Displacement piles Pre-cast shell piles Cast in-situ piles

8 Replacement piles Bored piles

9 Economic and construction considerations when selecting an appropriate foundation system The selection of the most appropriate system is a bit of a balancing act. All of the engineering options can be juggled until an optimum is identified.

10 What are the main issues to be addressed for basement construction? 1. Getting the loads from the superstructure to the soil. 2. Providing an optimised open space for use. 3. Resisting lateral soil pressures. 4. Preventing the ingress of moisture

11 Approaches for basement construction 1. Temporary support to basement excavations 2. Permanent basement wall construction prior to excavation 3. Top down basement construction

12 What are the questions to be addressed when deciding on a frame type? 1. What material and method to use for constructing the frame? 2. How is the frame organised and stabilised? (Structural and construction efficiency) 3. What type of floor system will be used in the frame?

13 Non-composite floor

14 What can go wrong during the installation of noncomposite hollow core planks? Refer back to the Case study - entitled Construction Laborer Dies after Falling off Collapsed Precast Concrete Floor Slab Source:

15 Composite floor

16 What other questions should be addressed when deciding on an appropriate structural frame for a building? How much it is going to cost? How long would it take? (speed of construction) Is it appropriate to the size and nature of site? Does it meet the client requirements? What is the availability of labour and material?

17 Approaches for the installation of Cladding / Curtain walling

18 Stick system

19 Unitised curtain walling For detailed installation steps go to:

20 Lattice Beams, Trusses and Girders Large spans in excess of 25m can be formed using these systems.

21 Proprietary sections are manufactured in standardised section sizes, however, these may not be appropriate either in terms of achievable span, or in terms of architectural style. Therefore, many truss sections are bespoke, or built up specifically for specific building structures.

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23 What are the factors that must be taken into account in the design and selection of a suitable roof structure? Function of the building Span of the roof Height of the space Aesthetic and design requirements Economic considerations Construction considerations. The environment

24 GREEN ROOFS Green roofs are vegetated layers that sit on top of the conventional roof surfaces of a building. Green roofs may also include additional layers such as a root barrier or drainage and irrigation systems

25 What are the types of offsite production? 1. Volumetric 2. Panellised construction systems 3. Hybrid construction 4. Sub-assemblies and components

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27 What are the drivers for offsite production? What could be the clients perceptions of the benefits of offsite production? Source: Blismas et al., 2007

28 Labour and training 1. Do we have enough labour? 2. Are they are appropriately skilled and qualified?

29 Transport

30 Transport

31 Carbon footprint of on-road transport

32 Cranes

33 Site layout and access Site organisation

34 Natural resources Construction projects Waste and pollution

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36 rationalisation Low carbon construction is about.. of energy consumption and thereby minimising the.. impact of construction activity on our planet.

37 How to attain low carbon construction? Do things differently and challenge existing ways of working and definitely there would be more potential for innovation.

38 Cut down waste - SWMP Use of renewable energy Minimise CO 2 emissions

39 More things to do Make the construction process more efficient Building design Materials used (performance and source) Energy refurbishment of buildings

40 Environmental audit: a case study Land use Ecology and nature conservation Landscape Air quality Cultural heritage Traffic noise and vibration Pedestrians and cyclists Vehicle travellers Pre-construction cost = 50m!

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42 Drivers for low carbon construction Government intervention Incentives Legislation Promotion

43 Challenges when considering low carbon construction and the energy refurbishment of buildings Technology-related (performance and efficiency) Investment-related (Funding, ROI, Cost/Benefit analysis) Government initiatives (e.g. Feed-in-Tariffs) Improved data collection, reporting and use Development of new and better skills

44 What is the key performance shortcoming of renewable energy?

45 Development of new and better skills

46 Good Luck