1) What is the difference between dead loads and live loads? Give at least five (5) examples of each.
Dead Load: The dead load includes loads that are relatively constant over time, including the weight of the structure itself, and immovable fixtures such as walls, plasterboard or carpet. The roof is also a dead load. Dead loads are also known as permanent or static loads. E.g.: wall loads, Roof loads, Window loads, floor load, and tiles load.Live Load: Live loads are the weights of people, furniture, supplies, machines, stores, and so on, borne by the building during its use and occupancy. The loads of small or movable pieces of equipment are considered as live loads, but equipment that belongs to the building and is fixed and heavy is regarded as dead load. E.g.: furniture, air conditioner, movement of people, people, supplies, machines and etc.The major difference between live loads and dead loads is: Dead loads can be calculated accurately as they are constant but the live loads cannot be calculated exactly.
2) Calculate the dead load exerted by a 13mm Gypsum plaster board sheets that are fixed to a wall which is 5m wide and 3m in height.
Show your working.
Total sqm = (5 x 3) =15sqmWeight / unit area N/m2 = 15 x 220 = 3300 N/M2= 3.3 KN
3) Calculate the expected live load on a column which supports 15sqm of floor in a retail shop.
Live load for Retail shop = 5.0 Kn/m2Expected live load on a column of 15sqm = 15 x 5.0 = 75Kn/M2
4) Give three (3) examples during mixing and pouring of concrete which can decrease the strength properties of concrete.
5) It is proposed that a medium masonry residential building of 15m in height will be demolished on a small site. The building is suspected of containing asbestos and lead paint.
Consider each point below and explain the main requirements and considerations to be followed for each area:
6) Pick a retaining wall system from the list below and identify, via a diagram, all the forces exerted on the wall and the resisting forces of the wall.
Draw the wall on a blank piece of paper, identify all of the forces exerted on the wall and upload a scanned copy of your drawing below.
7) In accordance with Australian Standards, provide a methodology for a concrete slump test.
What constitutes a pass or a fail and what rectification steps must be taken in the event of a test fail?
Give a brief of slump test
8) Explain how excessive water in a concrete mix can compromise the structural integrity of concrete.
In your response, provide two (2) examples of how the risks of excess water in concrete can be avoided on site.
Monitor the pour & don’t allow concrete truck or pump guy to put water
9) Explain why it is important that concrete cures correctly.
How can you ensure a concrete slab is allowed to cure appropriately?
In your response, refer to relevant standards.
It will get right strength quicker, avoid shrinkage cracks.
10) What is “consolidation” in a concrete pour?
Explain its importance and methods for how the concrete should be consolidated.
It doesn’t allow segregation of material and mixes thoroughly and avoids air pockets
11) Explain the purpose and required positioning of joints in masonry construction.
Allows for movement, avoids cracking, expansion and contractions. Change of material, long distance
12) How should a tilt up concrete panel be supported immediately after it is erected?
Diagonally bracing it at 45deg. At minimum two bracing per panel and can’t be out 90deg
1)
The factors to consider when planning the forming and storing of concrete tilt up panels are location, site limitations, schedule, budget, structure, building size, and construction sequencing.
2)
Structural Integrity of Footings
Action I Take
NCC/BCA Code
Accepted Principles
Construction
Slab and footing construction
AS 2870
Concrete slabs
Retaining walls
Positioning of steel reinforcement
Footing widths and depths
Stiffening beams
3
Damp Coursing and Termite Barriers
Concrete slabbing and damp proofing
AS/NZS 2904: 1995
AS 3660.1: 2014
Damp proof course
Construction of concrete slabs to prevent termites and dap proof courses to prevent damping
4)
Structural Integrity of Slabs, Bearers and Joists
Concrete
AS 1684
Shear wall
Wind bracing
Columns
Beams
Construction of beams, columns, wind bracing, shear wall and slabs to bear weight of dead and live loads
5)
Structural Integrity of Floor Systems
Concrete and damping compound
Damp proofing
Construction of retaining walls to prevent lateral pressure from soil and, damp proofing to prevent damping.
6)
Structural Materials
Term
Definition
Accommodating Behaviours
Stress
Refers to force per unit area within a material that comes from external forces
Use of composites with good tensile and compressional strengths
Strain
Refers to the ratio of elongation to the original length as a result of an external force
Introduction of movement joints at the design stage.
Elasticity
The property of material to return to its original shape and size when strain/force is removed.
Use of materials with big elastic limits
7)
Prestressing refers to the process of compressing concrete prior to application of external load.
8)
The procedure for ensuring the quality of structural frames is as follows:
9)
The following procedure helps in ensuring quality of roof trusses
10)
Structural Integrity of Cladding
Cladding
BCGBC4010A
Structural bracing
External walls are clad so that the cladding material acting in tension connects the bottom and top plates to provide tie-down.
11)
Standard Controls
Hazards
Standard Control Measures
Work at Heights
All activities involving heights of 2 m and higher must be performed using fall protection equipment in accordance with workplace safety standards Act 2005.
Working with Asbestos
All activities related to asbestos exposure must be conducted in strict compliance with the code of practice for safe removal of asbestos [NOHSC:2005] and WHS regulation 419
Working with scaffolding
All activities involving use of scaffolding must be conducted with aid of fall protection equipment in accordance with work safety standards Act 2005
The site is in the shape of a rectangle measuring 135 m * 40 m. It is enclosed by roads on the south-west and northwest sides. On the remaining sides are multistorey residential apartments. Currently, the site has four 3-stoeyr unoccupied residential buildings. In front of the buildings is a large open parking lot.
According to Sydney 1:100000 Geological Series Sheet, the soil underlying the site is the dark grey Ashfield Shale. However, the site is nearby a geological boundary with Hawkesbury Sandstone, comprising a medium grained quartz with minor layers of laminite and shale.
The excavations will be supported due to the low strength of the sandstone until construction of permanent basement walls is complete. Shoring support will be used from the surface of ground to the consistent high strength rock. However, in some locations like the south western side of the site where the high strength rock is shallow, temporary batters OF 1.5H: 1V may be adopted instead of shoring.
In addition, soldier piles with in-fills of reinforced shotcrete panels would be used at 2 m centres and be socketed into the sandstone.
A damp proof course is a system that helps prevent a building from dampness and its related effects. A damp proof course is laid on top of the ground adjoining the building’s plinth level in the wall’s entire width. The thickness of the medium rose building visited was 20 mm.
Prior to installing a damp proof course, the brick work must reach the plinth level. The damp proof is prepared by mixing a damp proofing compound with sand and cement (2:1) with sufficient amount of water. Once the mixture is ready, it is laid in the full breadth of the brick underneath it. The thickness of the damp proof layer was kept at 2.5 cm, which is the recommended thickness. After installation, the course is cured for 7 days, dried, and then coated with a layer of coal tar.
The damp proof course for the medium rise building showed robustness since there were no potential weak spots where penetration could occur later. This robustness was attributed to the strict adherence of Australian standards for laying of a damp proof course.
3)
The type of services assessed in the medium rise building under review include energy distribution system, lighting, control systems of the building, alarm and security systems, ICT networks, energy supply, plumbing, drainage and water systems, and fire safety system.
Building services perform an integral role in a building’s design, not only in terms of strategies to be achieved, but also in standards to be met. Thus, the design of the building services will be integrated into the building’s overall design at an early stage.
To protect the building’s services from clashing with other components of the building, such software and techniques as 3D CAD and BIM will be used. These clashes if not prevented can lead to variations and delays on site. In addition, these building services will be necessary for fulfilment of various Australian Standards and building codes such as AS 2436 for noise control.
The building is a two-storey class 2 building that would be erected in accordance with all the relevant Australian Standards and Building Codes.
In addition a cantilever retaining wall will be built to hold back soil. The wall will rest on the foundation slab. The foundation slab being loaded by backfill, it will stabilize the wall and prevent it from sliding and overturning.
a)
Prior to commencement of demolition works, legislative requirements must be fulfilled. First, the AS 2601 demolition of structures act must be complied with. Secondly, the building regulations applicable to the Australian Codes of practice and Standards must be met. These regulations include OH&S code of demolition practice, OH&S code of construction and building workplaces practice, OH&S Asbestos regulations, and AS 2436 for noise control guide.
b)
The three provisions for safety are:
c)
The structural design and structural principles of buildings are integral factors to consider during demolition. For instance, removal of prestressed concrete can be done manually or by mechanical demolition. Similarly, non-load bearing walls can be removed manually or by mechanical means. Also, adjoining walls are only demolished by hand and not by any other means to protect the immediate environment and the adjoining buildings.
d)
The building being under demolition was a low-rise building of 30 metres in height.