[SOLVED] CIVE5975/CW1/2024 Foundation design for a cable car pylon Python

CIVE5975                             Foundation Engineering

CIVE5975/CW1/2024             Foundation design for a cable car pylon

Aim:                    •       To interpret site investigation data

•      To identify potential hazards and failure mechanisms

•      To design suitable foundations for a wind turbine

Skills:                  •      Interpret site investigation data to select design parameters

•      Produce effective, economic design of foundations

•      Develop an understanding of methods used to calculate ultimate limit state and serviceability limit state for foundations

Outcome:            •      Design of suitable foundations considering the soil conditions, the loading

conditions, and the effect of environmental loading

•      An economical design

Brief:           Outline

A new public transport cable car system, is to be constructed in Kingston upon Hull along the northern bank of Humber river. The system will have a total of 8 cars with a capacity of carrying 8-10 persons/car  and will stretch over 4km. Each car is 2mx 1.8mx 2m and attains a maximum speed of 8m/s. Towers are located 300m apart, and each tower has an overhang of 3m on either side with cables (thickness of 1.5inches) for cars in opposite directions.

You are required to design the foundation for an intermediate tower/pylon of 2m diameter and 28mhigh, on top of a concrete pedestal (2.5mx 2.5m) of 2m height. The area around each tower is made of 0.5m thick block paving such that the surface of the block paving is at the original ground level. Assume an imposed traffic load of 5kPa from the surrounding traffic.

Requirements

You must produce design calculations for three foundation schemes for an intermediate twor/pylon. The ground profile and the properties of the soils are listed in the table below. At this stage, a feasibility report is all that is required. You must suggest a suitable range of foundations for the proposed structure, which must include a shallow foundation, a deep foundation and ground improvement schemes. The design should be technically sound, economic and safe.

Soil Conditions

A summary of the findings from a ground investigation is given below.

Depth below ground level	Soil type	Unit   weight	Cohesion	Angle of  shearing  resistance	Undrained* shear strength kPa	SPTN	Coef. of volume change
m		kN/m³	kPa				m²/MN
0 – 0.3	Topsoil	16	3	20	–	–	–
0.3 – 2.1	Firm clay	19	0	25	0.6σv’	–	0.1
2.1 – 5.3	Soft silty clay	17	0	20	0.3σv’	–	0.5
5.3 – 6.2	Medium dense sand	17	0	27	–	15	–
6.2 – 13.5	Firm clayey silt	21	10	30	90 + 20z	–	0.09
13.5 – 18.4	Stiff to very stiff clay	22	20	39	225+3z		0.05
>18.4                 Chalk

* z measured from the top of the layer.

Costs

The piling contractor will use either British Standard Universal Bearing Piles at £1050 per tonne or cfa piles (300mm, 450mm, 600mm and 750mm diameter) at £750 per tonne. Shallow foundations, foundations for pile caps and other associated excavations will cost:

Item	Unit	Cost
Excavation in sand/ sandy silt including disposal	m3	80
Excavation in clay/ clayey silt including disposal	m3	120
Excavation in gravel and made ground including disposal	m3	150
Excavation below water table (additional cost)	m3	50
Imported fill	m3	80
Mass concrete	m3	60
Reinforced concrete	m3	120
Steel piles	tonne	1050
CFA piles	tonne	750
Formwork support for foundations and pile caps	m2	50
1200mm deep cement/soil mixing	m2	120
1200mm reinforced gravel raft	m2	120
Stone columns	m3	70
Imported fill for preloading and disposal	m3	120
Wick drains	m	5

Report:       There are three tasks to complete. The first two tasks will be formative,i.e. they will not be marked but

will be used to give you feedback. You need to complete these tasks to design the foundations.

The first is an overview of the hazards including the loads and ground conditions you will consider when designing your foundations. In addition to the hazards, you should also include your calculations for the loads. The submission should be in the form. of a fully labelled cross section, table of hazards and calculations out in an approved manner submitted to the VLE by the 1st November 2024.

The second is a list of assumptions that you will make to produce the design covering the client and statutory requirements, the technical aspects of the design (e.g., combinations of actions, soil properties) and possible conceptual designs. You can use sections 1 to 7 of the final report as a guide. This must be submitted to the VLE by the 15th November 2024.

You must provide at least three alternative designs with supporting calculations in your final report. It is recommended that you consider a shallow foundation, a deep foundation and ground improvement schemes.

The design calculations can be typed or handwritten. If you choose to submit typed calculations, they should be presented in a similar manner to the hand calculations and be fully explained. No matter which method you use, the presentation of the calculations will be assessed. This must be submitted to the VLE by 20th December 2024.

The design report should include the following:

1.    A cover sheet including the title, date and name of authors

2.    Summary (up to 300 words)

3.    Contents list

4.    Introduction including clearly stated requirements

5.    Description of the load combinations

6.    Description of the assumptions

7.    Overview of the design methodology

8.    Overview of the design

9.    References

10.  Appendices containing the handwritten design calculations

The body of the report (Sections 1 to 9) should be typed in Black, Times New Roman, 11pt with single line spacing. Headings (Blue/Black, Times New Roman, 11/12pt) should be in bold and numbered 1, 1.1,  1.2, 2 etc. and should be preceded by one line. Paragraphs must be single line spacing, left justified with a single line between the paragraphs. Margins should be 2.54cm top, bottom and right and 3.17cm left in A4 size.

The Harvard system should be used for references.

All tables and figures in the body of the report must have a title and be numbered. It is important to include figures as they help the explanation. However, if a figure is included then you must ensure that it is discussed in the report.

The calculations should be attached as an appendix. All assumptions and sources of information should be clearly stated. Calculations should be supported by figures.

The body of the report (Sections 4 to 8) must not exceed five pages.

Marking:    The first two reports are formative to give you feedback on your design. No marks will be given for late

submission. The marking schedule for the final report will be as follows:

1.    Presentation                                               10%

2.    Statement of assumptions                         10%

3.    Hazard identification                                10%

4.    Load identification                                     10%

5.    Design method and conceptual design     20%

6.    Calculations                                               20%

7.    Overall design                                            20%

You must demonstrate that your design satisfies the ultimate limit state and serviceability criteria. In addition, you must produce a Bill off Quantities.