Structural Design And Construction Planning Essay.

Difference between Dead Loads and Live Loads

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) =15sqm
Weight / 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.

Show your working.

Live load for Retail shop = 5.0 Kn/m2
Expected 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. 

1. Cement and water ratio can decrease the strength of concrete
2. Compaction of concrete
3. Temperature and weather when concreate is poured.

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:

• Who you will engage to undertake the work and why? Consider nsw licensing requirements.
• What should be the sequencing of works?
• How will the presence of hazardous materials be addressed?
• What is the requirement for hoardings?
• What services are required on site?
• What other aspects relevant to the demolition work must be complied with before proceeding with the work?

1. Demolition will be done by engaging Licensed demolisher. And require license person who can handle asbestos. Qualified person who can handle lead paint.
2. Sequence of work:
   Obtain Construction certificate for Demolition
   · Get the building vacated
   · Disconnect Power & Gas
   · Site Establishment by putting temporary fence, Shade cloth over fence,
   Sediment fence
   · Remove any existing lead and asbestos.
   · Get demolition started as per approved conditions.
   
   
3. Hazardous Material will be isolated and separated during demolition work. Asbestos will be packed in bags and disposed at asbestos centres
4. Put up the board showing the work timings, Safety instruction board outside fence, SWMS to be maintained onsite.
5. Water, temporary toilet facility and power is the most important service to be required
   onsite during demolition.
6. Before proceeding to demolition services like gas and electricity should be disconnected. Construction certificate for demolition should be obtained. If any trees need to be protected than they should be covered or make safe by temporary fence.
   Demolition plan

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.

1. Gravity Retaining Wall
2. Cantilever Retaining Wall
3. Piling Retaining Wall
4. Anchored 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? 

Calculating Dead Load

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)

3

4)

5)

6)

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:

• Check for the fabricator’s qualification and experience
• Check the material being used
• The equipment used in the fabrication process must meet the required standards
• Finally, take the measurements of the steel parts to see if they meet the measurements in the design

9)

The following procedure helps in ensuring quality of roof trusses

• Check the truss layout plan
• Cross-check the manufacturer’s specifications for lateral stability, tie-downs, and bracings
• Check the roof truss certification
• Assess whether the supporting structure is adequate
• Check if the overall length and width of wall as well as dimension of wall fit the roof truss
• Check for the availability of girder trusses support
• Check for spacings and plumb
• Check for all fixings and tie-downs
• Check for location of specialized trusses
• Ensure trusses have not been modified or adjusted on-site
• Check for eave overhangs
• Check for trimming to manhole

10)

11)

1)

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.

2)

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:

• OH&S Asbestos regulations
• AS 2436 for noise control guide
• OH&S Asbestos regulations

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.