17 - Construction Technology And Environmental Services Flashcards
612 - What RIBA Stage is on-site construction?
RIBA Stage 5 - Manufacturing and Construction
613 - What is buildability? (2)
1) Buildability can be defined as the EXTENT to which the DESIGN of a building FACILITATES the ease of CONSTRUCTION.
2) To help improve buildability, EARLY CONTRACTOR INVOLVEMENT should be considered to benefit from their experience and expertise.
614 - What are the benefits of off-site construction over in-situ? (4)
1) SAFETY - Hazards such as falls from height are more likely to occur on site than in a factory.
2) EFFICIENCY and QUALITY - Construction takes place in a controlled environment.
3) SUSTAINABILITY - Reduction in waste produced.
4) SPEED - Work in the factory can be scheduled to begin at the same time as other activities on site, resulting in a shorter build programme.
615 - What is the difference between building works and civil engineering works? (2)
1) Building works - ALL TYPES OF BUILDINGS such as houses, offices, shops, hotels, hospitals etc.
2) Civil engineering works - drainage schemes, highways, culverts, bridges, retaining walls etc. (INFRASTRUCTURE)
616 - What are temporary works? (1 + 4 examples)
Temporary works are the parts of a construction project that are NEEDED TO ENABLE the permanent works to be built, they are usually required for safety or access reasons. Examples;
1) Propping
2) Scaffolding
3) Formwork
4) Excavation support
617 - What are hoists?
Designed for the VERTICAL TRANSPORTATION of materials and / or people.
(See book for photo examples)
618 - What is shoring?
FORM OF TEMPORARY SUPPORT given to existing buildings and excavations. The purpose is to prevent collapse or excessive movement.
619 - What is a culvert?
A culvert is a TUNNEL-LIKE STRUCTURE that is constructed to allow WATER TO FLOW UNDER a road, railway line or similar obstruction.
(See book for photo examples)
620 - What is the purpose of a drainage head wall? (2)
1) A head wall is a small RETAINING WALL / structure built at the INLET or OUTFALL of a STORM WATER drainage pipe.
(See book for photo examples)
621 - What is the substructure of a building? (3)
1) Substructure is the LOWER PORTION of the building (in the ground) which SUPPORTS the superstructure.
2) Transmits the loads of the building to the ground.
3) Includes foundations, basements and retaining walls etc.
622 - What is ground heave? (2)
1) Ground heave is usually associated with clay soil which SWELLS WHEN WET, causing the upward movement of the ground.
2) As the soil generally cannot expand downwards or sideways, the result is that the exposed upper surface of the soil rises up.
623 - What are some of the techniques available for ground improvement? (6)
1) Vibro compaction
2) Vibro stone columns
3) Vertical drains and vacuum consolidation
4) Soil mixing
5) Dynamic compaction
6) Dynamic replacement
624 - What are the different forms of excavation? (5)
1) Site clearance operations (removing vegetation and rubble)
2) Stripping topsoil
3) Reduced level dig (to reach formation level)
4) Cut and fill
5) Excavation for foundations
625 - What are the key factors the contractor should consider when excavating? (6)
1) NATURE of the soil and MOISTURE CONTENT of the ground
2) METHOD of excavation
3) If GROUND SUPPORT SYSTEMS are required
4) DEPTH of excavation
5) UNDERGROUND services and drainage
626 - Can you explain some of the techniques to waterproof a basement? (2)
1) TANKING - Materials such as asphalt, polythene sheeting, bitumen etc. are applied internally or externally to provide a continuous membrane to the base slab and walls.
2) DRAINED CAVITY - This method accepts a small amount of water seepage will occur. Cavity walls are formed, the water seepage is collected in the cavity and drained or pumped away.
627 - Have you come across the term SUDS? (3)
1) Sustainable Urban Drainage Systems.
2) SUDS are DESIGNED TO MANAGE STORMWATER locally (as close to its source as possible), to mimic natural drainage and encourage its infiltration and / or attenuation.
3) SUDS help to REDUCE the RELIANCE on EXISTING drainage infrastructure.
628 - Can you detail a typical road build up please? (4)
1) Compacted and rolled type 1 - sub base (100 - 250mm)
2) Base course (70 - 150mm)
3) Binder course (50 - 100mm)
4) Wearing / surface course (20 - 40mm)
629 - What is the purpose of a foundation? (2)
1) Foundations PROVIDE SUPPORT for structures, transferring their load to the ground to avoid excessive settlement.
2) Foundations should bear the loads of the superstructure.
630 - What are the typical considerations when selecting the type and size of the foundation? (5)
1) The total load of the building
2) Nature and load bearing capacity of the ground
3) Type of structure
4) Cost
5) Construction constraints (for example, their proximity to adjacent buildings / structures)
631 - What are the different types of foundation? (4)
1) Strip foundations
2) Pad foundations
3) Raft foundations
4) Piled foundations
632 - What is a raft foundation?
A raft foundation is essentially a CONTINUOUS SLAB that EXTENDS OVER the entire FOOTPRINT of the building. The raft spreads the load of the building over a larger area than other foundations, the stress acting on the ground below is reduced.
633 - What are pad foundations? (2)
1) Pad foundations are typically used to SUPPORT INDIVIDUAL or MULTIPLE COLUMNS, spreading the load to the ground below.
2) They are usually square or rectangular on plan and can be reinforced or non-reinforced.
634 - What are strip foundations?
As the name suggests, the formation is in a strip of LINEAR structure that ultimately serves to spread the weight across the total area of the ground, typically used to support masonry.
635 - What are pile foundations? (4)
1) A pile is a COLUMN (usually concrete) that EXTENDS DEEP INTO the GROUND.
2) Where the bearing capacity of the soil is poor or imposed loads are very heavy, pile foundations may be required.
3) There are two main types of pile;
- End bearing pile
- Friction piles
4) There are two main construction methods;
- Bored piles
- Driven piles