Reference no: EM132339782

Case Study

Project details

This project requires you to interpret and evaluate a structure in the built-environment. Engineers make decisions on materials, member shape and the connections for the individual members that make up a structure based on their understanding of how each of them performs under loading and over time. This project requires you to be that engineer and consider how these factors influence material choice and building shape.

You (an engineer) have been approached by a client who wished to build a tall timber building at Robina, Gold Coast. The client recently visited Norway where he was inspired the Tall timber building named, “Treet” and now wishes for a very similar building to be built in Robina.

In preparation for the future development you will need to assess the “Treet - a 14-Storey Timber Residential Building” from an engineering point of view. The following descriptive tasks are to be completed as you assess the structural performance of the building and prepare some details for the design and construction of the building at Robina, Gold Coast, Australia.

Descriptive tasks

Respond to the following tasks in the following order.

Introduction

1. Provide a summary of the structure detailing the design philosophy of the structure (consider aesthetics, function and design statements) (~150 words)

Loading

Dead loads

2. Annotate on pictures of the structure all elements that contribute to the structural dead load. For each element, also indicate the material used. Be sure to include items that are also considered super-imposed dead loads. You may need to use at least three different pictures to show all internal and external elements.

Dynamic loads

3. Create a live loading plan for a typical floor plan of the building. You must use the values form the AS1170.1. The plan should consist of a floor plan with different areas highlighted based on its usage (e.g. storage, kitchen etc.) and a legend indicating the associated design pressure (AS1170.1) based on the area’s use. There are some floors that also have a different usage (e.g. roof), provide a list of these uses and the associate design load. The floor plan can be found in “Some structural design used of the 14-storey timber framed building “Treet” in Norway by Malo K et.al. 2016”.

4. Determine the Vr for the structure based on AS1170.2. You may assume the structure was built on Bond University Campus, Robina. Ensure that you detail all assumptions/factors that you have used. (You only need to calculate the VR which is the regional wind speed. So, do not consider shielding, terrain, topography etc.)

Materials

Durability

5. The structure is built primarily from concrete, timber and steel. Give one fire and two durability issues common to the steel and concrete and describe how the issue was/should have been managed. (Hint: you could create a list of issues for each material and then detail the appropriate management strategy for each). High quality responses to this task will require you to provide evidence of the solution integrated in the Treet building (either from a photo or literature).

6. The design of a building made primary from timber often requires extensive management strategies around the control of fire and durability. What strategies (give at least 2 for each) were employed by the designers of this building for:

i. fire

ii. durability

Also, for each issue, identify one other solutions available for the management/design of the specified issues that was not used in Treet.

Structural systems and Performance

Load paths

7. Draw the load path for a person standing on the 12th floor. The floor plan can be found in “Some structural design used of the 14-storey timber framed building “Treet” in Norway by Malo K et.al. 2016”. You need to provide both plan and elevation view.

8. Describe in words the load path for the wind and then draw the load path. Only consider one wind direction. (hint: You will first need to identify the stability systems for the structure and also consider how the wind is transferred from the façade to the structural systems).

Vertical System

9. Describe the vertical structural system. i.e. how is the building transferring the dead and live loads to the foundations. Be sure to identify the key design elements.

Lateral System

10. Describe how stability is being provided to the building? Classify the system (see tall building stability in the stability lecture) and suggest an alternate system that could be adopted. If the alternate system was adopted, how would it have affected the architectural layout?

11. Describe what strategies have been engaged by the engineers to reduce the dynamic effects of wind on the building.

Flooring systems

12. In the current structure, the flooring for the “power-storey” is made from pre-cast concrete panels laid over glulam beams. Describe how the structural system of the floor (and potentially the building) would be different if the pre-cast concrete panels were replaced with CLT panels?

Earthquake

13. It is commonly noted throughout the papers published about “Treet” that the wind load was the governing load and therefore earthquake effects could be ignored in accordance with the Eurocode and Norway annexes. However, the earthquake code in Australia was recently amended and in many cases earthquake is the governing design load for mid-rise structures (5-20 stories) on the Gold Coast. Describe two earthquake design/management systems that could be implemented into the structure. Which one do you think would be most suited to this building? Justify your choice.

Connections

14. Consider the connection of the glulam members in the glulam truss system. List and describe two reasons this type of connecter was chosen (e.g. size/type of force, constructability). Then discuss the load path through the connection and identify the types of forces (e.g. tearing) in each element of the connection.

Soils and Footings

Geotechnical testing

15. Create an outline of the geotechnical tests (give just 5) that would need to be conducted prior to the design and construction of the structure and footings. Outline the purpose of each test and how its result can impact on the design of the foundations (e.g. a high shear strength means that simple raft/pad footing may be used while a low shear strength may mean that deep foundations are needed).

Footing systems

16. Describe the footing system used for this structure. Draw a cross section (from the first level to the bottom of the piles) of this footing and label all elements.

Other considerations

Deflection

17. Considering the serviceability criteria of deflection. Identify and calculate the limits (e.g. rafter = span/300 = 6000/300 = 20 mm) for all relevant building components of the Treet residential building. Use the limits prescribed by the Australian Standards. (See Table C1  AS1170.0)

Construction process

18. Briefly describe the construction process of the Treet residential building. Break the construction up into at least 6 steps and provide 1-2 sentences describing what is happening and anything unique to the step (e.g. waterproofing).

Indirect actions

19. It is known that creep, thermal actions and axial shortening are issues commonly experienced by tall buildings. Create a set of management strategies for these three issues in the context of the Treet Building. (hint: there is limited evidence of the management of these in the provided literature so you may need to consider how other buildings have managed these issues and suggest if the solution is appropriate for the Treet Building).