E4014 - Construction Surveying

1. E4014 - Construction Surveying HYDRAULICS

2. Introduction • surveyors • usually not be directly involved in the design of hydraulics systems • most certainly will be responsible for the setting out of such systems. • surveyor may need to alter the design of a system ‘on-site’ • the principles involved in this field must be understood.

3. Introduction • It is with this in mind and the desire to make you better able to understand the requirements of the engineer or design draftsman responsible for the project that this module is included.

4. Definitions & DiscussionsHydrostatics & Hydrodynamics • Hydrostatics • The study of the properties of fluids which are at rest or in equilibrium (e. g. storage systems such as dams and reservoirs). • Hydrodynamics • The study of the properties of fluids which are in motion in pipes and channels (e.g. water or sewerage reticulation and drainage systems).

5. Definitions & DiscussionsFluid • can offer no permanent resistance to any force causing change of shape. • flow under their own weight • take the shape of any solid body with which they are in contact.

6. Definitions & DiscussionsFluid cont • change of shape is caused by shearing forces; therefore if shearing forces are acting in a fluid it will flow. • Conversely, if a fluid is at rest there can be no shearing forces in it, and all forces are perpendicular (normal) to the planes on which they act.

7. Definitions & DiscussionsFluid cont • Fluids are divided into liquids and gases. • Liquid • difficult to compress; • a given mass occupies a fixed volume irrespective of the size of the container holding it • a ‘free surface’ is formed as a boundary between the liquid and the air above it.

8. Definitions & DiscussionsFluid cont • Fluids are divided into liquids and gases. • Gas • easily compressed; • expands to fill any vessel in which it is contained • does not form a free surface.

9. Definitions & DiscussionsPressure & Intensity of Pressure • Pressure • force exerted by a fluid on the surfaces with which it is in contact, or by one part of a fluid on the adjoining part. • intensity of pressure at any point • force exerted on the unit area at that point • measured in newton’s per square metre in SI units • An alternative metric unit is the bar, which is 105 N/m2.

10. Definitions & DiscussionsPressure - Example

11. Definitions & DiscussionsPressure Scales • Atmospheric Pressure • The earth is surrounded by an atmosphere many miles high. • The pressure due to this atmosphere at the surface of the earth depends upon the head of air above the surface. • Atmospheric pressure at sea level is about 101.325 kN/m2, • equivalent to a head of 10.35m of water • or 760 mm of mercury approximately, and decreases with altitude

12. Definitions & DiscussionsPressure Scales • Vacuum • A perfect vacuum is a completely empty space in which, therefore, the pressure is zero • Gauge Pressure • the intensity of pressure measured above or below atmospheric pressure

13. Definitions & DiscussionsPressure Scales • Absolute Pressure • the intensity of pressure measured above the absolute zero, which is a perfect vacuum

14. Definitions & DiscussionsPressure Scales • absolute pressure = atmospheric pressure + gauge pressure, or • p(abs) = p(atm) + p(g)

15. Definitions & DiscussionsPressure Scales • absolute pressure = atmospheric pressure + gauge pressure, or • p(abs) = p(atm) + p(g)

16. Definitions & DiscussionsDimensions & Units • Dimensions • various physical properties that all matter possess • describe the state of things • Units • internationally agreed measurable quantities of the various dimensions • SI ( System International ) • kilogram, metre, cubic metre, metre per second, kelvin, ampere, and joule

17. Definitions & DiscussionsDimensions & Units • Seven base dimensions, each with its own base unit

18. HydrostaticsIntroduction

19. HydrostaticsIntroduction

20. HydrostaticsHydrostatic laws - Horizontal Pressure Variation • Horizontal Hydrostatic Law • Pressure has a constant value at a given horizontal level in a continuous fluid mass

21. HydrostaticsHydrostatic laws - Horizontal Pressure Variation

22. HydrostaticsHydrostatic laws - Vertical Pressure Variation

23. HydrostaticsHydrostatic laws - Vertical Pressure Variation

24. HydrostaticsHydrostatic laws - Vertical Pressure Variation

25. HydrostaticsHydrostatic laws - Vertical Pressure Variation

26. HydrostaticsHydrostatic laws - Example

27. HydrostaticsHydrostatic laws - Example 68670 Pa

28. HydrostaticsHydrostatic laws - Example 68670 Pa

29. HydrostaticsHydrostatic laws - Example PF due to water = 49050.0 Pa 68670 Pa

30. HydrostaticsHydrostatic laws - Example PF due to water = 49050.0 Pa 19620 Pa 68670 Pa

31. HydrostaticsHydrostatic laws - Example PF due to water = 49050.0 Pa PG due to water = 58860.0 Pa 19620 Pa 68670 Pa

32. HydrostaticsHydrostatic laws - Example PF due to water = 49050.0 Pa PG due to water = 58860.0 Pa 9810 Pa 19620 Pa 68670 Pa

33. HydrostaticsHydrostatic laws - Example PF due to water = 49050.0 Pa PG due to water = 58860.0 Pa 9810 Pa 9810 Pa 19620 Pa 68670 Pa

34. HydrostaticsHydrostatic laws - Example PF due to water = 49050.0 Pa PG due to water = 58860.0 Pa 9810 Pa 9810 Pa 19620 Pa PH due to benzine = 51796.8 Pa 68670 Pa

35. HydrostaticsHydrostatic laws - Example PF due to water = 49050.0 Pa PG due to water = 58860.0 Pa 9810 Pa 9810 Pa 19620 Pa PH due to benzine = 51796.8 Pa 68670 Pa 61606.8 Pa

36. HydrostaticsHydrostatic laws - Example PF due to water = 49050.0 Pa PG due to water = 58860.0 Pa 9810 Pa 9810 Pa 19620 Pa PH due to benzine = 51796.8 Pa 68670 Pa 61606.8 Pa

37. HydrostaticsHydrostatic laws - Example PF due to water = 49050.0 Pa PG due to water = 58860.0 Pa 9810 Pa 9810 Pa 19620 Pa PH due to benzine = 51796.8 Pa PJ due to benzine = 77695.2 Pa 68670 Pa 61606.8 Pa

38. HydrostaticsHydrostatic laws - Example -16088.4 Pa PF due to water = 49050.0 Pa PG due to water = 58860.0 Pa 9810 Pa 9810 Pa 19620 Pa PH due to benzine = 51796.8 Pa PJ due to benzine = 77695.2 Pa 68670 Pa 61606.8 Pa

39. Hydrostatics Pressure Units • Expressed in two ways • pressure head • the height of the free surface of a particular liquid above the surface in question • traditional pressure units • Pascals (Pa) = Newtons/square metre

40. Hydrostatics Pressure Units - Example

41. Hydrostatics Pressure Units - Example

42. Hydrostatics Pressure Units - Example

43. Hydrostatics Hydrostatic Pressure on Surfaces • A fluid in contact with a solid surface will exert a force on every small area of the surface. • The total pressure on the surface can be represented by a point force equal to the product of the pressure on the small element and its area.

44. Hydrostatics Hydrostatic Pressure on Surfaces • The point at which this force must act is the centroid.

45. Hydrostatics Hydrostatic Pressure on Horizontal Surfaces - example

46. Hydrostatics Hydrostatic Pressure on Horizontal Surfaces - example

47. Hydrostatics Hydrostatic Pressure on Horizontal Surfaces - example Pressure = 5886.0 N/m2 AreaBase = 6.0m2

48. Hydrostatics Hydrostatic Pressure on Horizontal Surfaces - example Pressure = 5886.0 N/m2 AreaBase = 6.0m2

49. Hydrostatics Hydrostatic Pressure on Inclined Surfaces

50. Hydrostatics Hydrostatic Pressure on Inclined Surfaces F