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1. Earth Work Quantities and mass haul diagram 5/30/2024 1

2. Earthwork Earth Work & Quantities 5/30/2024 2

3. Earth Work Road construction involve considerable amount of earthwork. Earthwork is simply the quantity of material to be moved or put in place to convert the natural condition and configuration within the ROW of the road to the section and grades described in the plans. 5/30/2024 3

4. Earth Work Includes(details) Clearing and Grubbing - clear off roots Excavation of drainage channels & trenches Excavations for structures Borrows Haul & Overhaul Grading Preparation of Side Slopes Reconditioning of roadway Other operations for preparing the sub-grade for roadway pavement construction 5/30/2024 4

5. Earthwork Quantity Quantity and Cost are calculated in m 3 either in its original form or by allowing for shrinkage and swell The rate of payment generally includes full compensation for excavation, formation of embankment, preparing of side slopes, disposal or borrowing with in the free-haul distance, and the preparation and completion of the sub-grade and the shoulders For borrowing or disposal involving more than the free haul distance additional compensation is necessary 5/30/2024 5

6. Earthwork of Road Earthwork activities Earthwork quantities and calculations. Area of cross sections. Determination of volume of earthworks by appropriate methods. The mass haul diagram Determination of the planned movement of materials. Calculation of the mean haul distance and the corresponding cost 5/30/2024 6

7. Clearing and grubbing the first operation to be undertaken in road projects. Definition: the removal of trees, stumps, roots, down timber, rotten wood, rubbish and other objectionable materials form an area marked on the plans. Clearing refers to the removal of materials above existing ground surface and Grubbing means the removal of roots, stumps and similar objects to a nominal depth below the surface. Clearing and grubbing constitute a single contract item that includes the removal of topsoil to a shallow depth 5/30/2024 7

8. (cont’d) Excavation: the process of loosening and removing earth or rock from its original position in a cut and transporting it to a fill section or to a waste deposit . Excavation Roadway and drainage excavation Excavation for structures Borrow excavation Roadway and Drainage Excavation. the excavation and grading of the roadway and ditches, including the removal and disposal of all excavated material and all work needed for the construction and completion of the cuts, embankments, slopes, ditches, approaches, intersections and similar portions of the work 5/30/2024 8

9. (cont’d) Excavation for structures. the excavation of material in order to permit the construction of culverts, foundations for bridges, retaining walls, and practically all other structures that may be required in a particular job. Borrow excavation Excavation of selected material transported into site of work for use in road construction or volume of material, which must be imported into section of the road due to a deficiency of ( suitablity ) material 5/30/2024 9

10. Classification of Excavation Rock excavation material that cannot be excavated without blasting or the use of rippers and all boulders or other detached stones. Common excavation excavation and disposal of all materials of whatever character encountered in the work, which are not classified as rock, borrow. Borrow excavation excavation of approved material required for construction of embankments. Unsuitable excavation the removal and disposal of deposits of saturated or unsaturated mixtures of soil and organic matter not suitable for embankment material. 5/30/2024 10

11. Haul and Overhaul Free Haul: when material is excavated it will be moved over a certain distance free of charge. NB: Only the excavation cost is paid, not the transportation cost of the material. Free Haul Distance(FHD): Distance over which excavated material is moved free of charge (usually 300 –500 m, but ranges 150 –900 m). Overhaul: is defined as the distance over which the excavated material must be hauled less the free haul distance. NB: there is extra payment for transporting material in addition to excavation cost . 5/30/2024 11

12. (cont’d) Overhaul distance(OHD): Distance over which excavated material is transported beyond the free‐hall distance. OHD = HD ‐FHD Economic Overhaul (EOH): Economic overhaul is a distance beyond which it is not economic to overhaul. Limit of Economic Overhaul(LEH) ‐ is the distance beyond which it is uneconomic to overhaul plus the free haul distance. LEH = EOH + FHD 5/30/2024 12

13. Haul and Overhaul Haul – is equal to the sum of the products of each volume of material and the distance through which it is moved( Σ Vi*Di). Waste – is the volume of material, which must be exported from a section of the road due to a surplus or unsuitability. Borrow – is that volume of material, which must be imported in to section of the road due to a deficiency of (suitable) material. 5/30/2024 13

14. Estimation of Earthwork Quantities The estimation of the quantity of material which must be excavated (cut), and the quantity of material required to raise the elevation of the existing ground (fill), is very useful in the development of a cost estimate for road projects . 5/30/2024 14

15. Estimation of Earthwork Quantities… Typical x-Sections Fill Cut Cut & Fill 5/30/2024 15

16. Soil Volume Change s Excavated in‐situ material used in embankments or fills may swell or shrink. It is important to determine the properties of a material in order to evaluate how these properties will affect the earthwork volume estimates. 5/30/2024 16

17. (cont’d) Material volume increases during excavation Decreases during compaction Varies with Soil type Fill depthg High fill 10 – 15% shallow fill: 20 –25 % 5/30/2024 17

18. (cont’d) 5/30/2024 18

19. Estimation of Earthwork Quantities Estimation of the area of cross‐section as a cut and fill. The distance between these areas, l (or L) Volume of earthwork Cut volume and Fill volume Area of cross section Coordinate method Trapezoidal rule Simpson’s rule 5/30/2024 19

20. 20 Areas of Cross-sections Methods For regular/level ground For irregular ground

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22. 22 Area for Regular Ground Area of a trapizod Cut d sd sd 1 b s s 1 Fill b sd d s 1 sd

23. Calculation of cross‐sectional areas Coordinate method With the coordinates of all the corners of a cross‐section known, the area may be computed by means of the coordinate method. The point of intersection of the center of formation with the centerline of the road (c) is used as the origin. The cut above the formation are written as plus (+) and those below as minus (‐). The distances to the right are written as plus (+) and those to the left as minus (‐). 5/30/2024 23

24. Fig. Area by coordinate method

25. (cont’d) Coordinate method The products along the marked diagonals are all positive and the product along the unmarked diagonals are all negative. The difference gives double area of the section. Area, A 5/30/2024 25

26. (cont’d) Trapezoidal rule: assumes that if the uniform interval (b) between the offsets is small, the boundary can be approximated to a straight line between the offsets. A 1 A 2 A 3 A n L L L O 1 O 2 O 3 O n+1 O n OR 5/30/2024 26

27. (cont’d) Simpson’s rule: assumes that instead of being made up of a series of straight lines the boundary consists of a series of parabolic arcs. 5/30/2024 27

28. Computation of Volume s Average end‐area method based on the volume of a right prism whose volume is equal to the average end area multiplied by the length. Prismoidal method a prismoid is a solid whose ends are parallel and whose sides are plane surfaces. 5/30/2024 28

29. (cont’d) Average end areas method V = ½ (A 1 + A 2 )L Where A 1 , A 2 : end cross section areas L: distance between cross-sections Example A = 30 m 2 A1= 36 m 2 L = 20 m V = ½ (30 m 2 + 36 m 2 )(20 m) = 660 m 3 5/30/2024 29

30. 5/30/2024 30 This formula is considered exact only if the end areas (A1 and A2) are equal. However, it is only an approximation if the end areas are not equal. If one end-area has a value of zero, the earthwork volume is then similar to the volume of a pyramid

31. Computing Volumes Prismoidal method A Prismoid is a solid whose ends are parallel and whose sides are plane or warped surfaces The Volume of a Prismoid is: A 1 & A 3 are parallel end areas a distance l apart and A 2 (Am )the area at the mid-length, found out by interpolating the linear dimensions. 5/30/2024 31

32. Tabulation of earthwork quantities 5/30/2024 32

33. Mass‐Haul Diagrams A Mass Haul Diagram is a continuous curve representing a cumulative volume of earthwork along the linear profile of a roadway or airfield Mass diagrams are extremely useful in determining the most economical distribution of material. Horizontal stationing is plotted along the x‐axis Net earthwork values are plotted along the y‐axis cumulative earthwork from the origin to that Point upward sloping curves (rising left to right) indicate a cut downward sloping curves (falling left to right) occur in a fill section peaks indicate a change from cut to fill and valleys occur when the earthwork changes from fill to cut 5/30/2024 33

34. (cont’d) Fill areas Cut areas -------Any horizontal line on mass diagram is a balance line – within balance line cut = fill 5/30/2024 34

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36. (cont’d) Any horizontal line which joins points on the curve where balance is achieved is called a balance line . The FHD and/or the limit of economic overhaul(LEH) are established and plotted on the mass haul diagram A vertical break between any two balance lines indicates an area where balance does not occur. At these breaks a shortfall (borrow ) or excess (waste ) material exists. A positive value at the end of the curve indicates that a waste operation will be the net result. A negative value at the end of the curve indicates that borrow is required to complete the fill . 5/30/2024 36

37. (cont’d) 5/30/2024 37

38. Mass Haul Diagram Drawing Procedures Mass Haul Diagram Drawing Procedures: Calculate the volume of fill and cut; cut is +ve and fill –ve. Calculate areas at cross-sections Correct the volume calculated by shrinkage and swell factors Tabulate the corrected aggregate volume Plot the mass haul diagram (scale: 1:2000 H and 1:500 or 1:1000 (cm:m 3 )V) Join points by a straight line or curves 5/30/2024 38

39. (cont’d) Calculation of Mass‐haul diagrams manually: Compute the net earthwork values for each station, applying the appropriate shrink factor. Net cuts have a positive value, net fills have a negative value The value (earthwork quantity) at the first station (origin) = 0 Plot the value of each succeeding station which equals the cumulative value to that point The scale length of a horizontal line connecting the center of gravity of the cut and fill sections is the average length of haul within that balanced section Determine earthwork volumes within each balanced section. Determine whether there is an overall balance, waste or if borrow is required 5/30/2024 41

40. (cont’d) If mass haul is drawn for each trial grade line it can be used for selecting the most economical gradient which balance the cut and fill. Once the formation level is designed, it can be used to indicate the most economical method of moving the earth around the project and a good estimate of the overall cost of the earth moving can be calculated. The required volumes of material are known before construction begins enabling suitable plant and machinery to be chosen and sites for spoil heaps(waste) and borrows pits to be located and direction of haul to be established. 5/30/2024 42

41. Thank you !! 5/30/2024 43

42. 44 An Introduction to Highway Drainage

43. INTRODUCTION Roadway (highway) drainage is the process of collecting, conveying, removing, and disposing o f surface water and underground water encountered  within the limits of the ROW and adjacent territory. Provision of adequate drainage system is an essential part of pavement design. Protection of pavement structure Improves road safety The serviceability of a highway is greatly dependant upon  the  adequacy of its drainage system. (20-25% Total cost) 5/30/2024 45

44. Cont… Problems resulting from poor drainage : S tanding water on pavements  is a danger  to traffic safety S eepage water  into pavement and subgrade leads to…  de velopment of   soft spots & break up of the surfacing . S treams  have the power to… d estroy roadways by  force & holdup traffic  by  flooding . 5/30/2024 46

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46. Cont…  A ffects of water on the pavement structure Presence of moisture causes: - reduction in the stability of the soil mass . - variation in volume of subgrade in clayey soils. - Waves and corrugations failure in flexible pavements. - Stripping failure in flexible pavements . - Mud pumping failure in rigid pavements. 5/30/2024 48

47. Cont…  Some of the major considerations of good roadway drainage design are: Facility to user safety. • Convenience to vehicular , bicycle and pedestrian traffic. • Aesthetics. • Flooding of the transportation facility and adjacent property. • Subgrade infiltration. • Potential erosion , pollution and other environmental concerns. • Economy of construction and maintenance etc. 5/30/2024 49

48. Why remove rainwater from the carriageway?  Water has a number of unhelpful characteristics which impact on highway performance. It is a lubricant reducing the effectiveness of tyre grip on the carriageway wearing surface which can increase stopping distances. Spray from rainwater being thrown up by car tyres can reduce visibility which can lead to delays in reacting to events on the carriageway. Drag on car tyres from local rainwater ponds can alter the balance of vehicles travelling at speed which can be alarming or cause skidding. 5/30/2024 50

49. Drainage and Drainage Structures …. Requirements for Highway drainage systems S urface water from carriageway and shoulder  should  effectiv - ely be  drained . Surface water from  adjoining land  should be prevented from entering the roadway . F low of surface water across the  road and shoulders  and along  slopes shouldn’t cause formation of  erosion or cross ruts . S eepage and other  sources of underground  water should be  drained off by the subsurface drainage system — In water logged areas  special precautions should be taken . Environmental consideration is also a critical one. 51

50. Cont… 5/30/2024 52

51. Cont … Factors to be considered in drainage design : Size of the area to be drained Expected maximum rainfall Slope of the surrounding terrain / possible rate of runoff Characteristics of the soil (incl.: permeability, tendency to erode ) Presence of springs or other underground water General elevation of the ground water level Minimum depth of cover required to protect pipes from traffic loads 5/30/2024 53

52. TYPES OF DRAINAGE Depending on nature of water and place we provide road drainage is classified into two Surface drainage systems Subsurface drainage systems 54

53. Surface drainage systems Def : The measure taken to control the flow of surface  water  is g enerally termed as  surface drainage. Surface Drainage system= Edge + Cross Drainage assets Structures that provide for surface drainage  include: Side: Roadway Crown, Shoulder, Side Ditches Cross: Cross‐sectional Ditches (Fords), Culverts, Bridges. The flow of surface water  adjacent to highways   is  frequently a ccompanied by  detrimental (harmful)  soil erosion  ,so that resulting in : —Destruction of  productive soils Clogging of  ditches and drainage structures 5/30/2024 55

54. Edge/Side Drainage Assets Mechanisms to remove rainfall from highway schemes are called edge assets. Edge assets can include any/all of the following:- 1. Kerbs and gulleys with carrier drains Gulleys and kerbs work together to transport and collect rainfall run-off into the highway drainage system. 5/30/2024 56

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56. Cont… 2. Combined kerb drainage system (Beanie-block) Proprietary drainage products which combine kerbs with a flow and collection system. These products are very good at collecting flows, especially in flat areas where a flow path isn’t likely. 5/30/2024 58

57. 3. Drainage ditches The historic method for flow collection, especially where kerbs are not installed. Water simply runs off the carriageway into the ditch. Management of these is usually provided by the relevant local authority highways team as are they connecting culverts, headwalls etc. Ditches can be defined as an open channel usually paralleling the highway embankment and within the limits of the highway right-of-way. 5/30/2024 59

58. 4. Combined filter drains These collect the run-off from the carriageway and the sub-base together with any run-off from cutting embankments. 5/30/2024 60

59. 5. Grass swales an open channel that collects water from hard surfaces and allows it to percolate into the ground, reducing the amount of runoff leaving the road or property. 5/30/2024 61

60. Cross Drainage Assets Are highways drainage structures /systems which are designed and constructed to provide for the passage for water from one side of the road to the opposite side; from higher elevation to the lower elevation . Cross Drainage structures consists of culverts, causeways ( a raised road across low or wet ground ) and bridges are essential components of any highway. In any road network cross-drainage (CD) structures are common features and they play an important role in keeping the road network free from flooding, overtopping or breaching during floods . 62

61. Cross Drainage Assets… The purposes of CD structures in roads are : · To divert and allow a free passage of the surface flow from one side to the other. · To allow cross-drainage of the waste-water from village/town areas through which the road passes. · To allow water passage for irrigation channels, watercourses etc . · To cross over the rivers, tributaries , streams/ hallas , rivulets , brooks , drains etc 5/30/2024 63

62. Cross Drainage Assets…cont’d Pass natural stream flows or runoff under roadways Outlet for detention basins 5/30/2024 64

63. Surface drainage systems…Design Surface Drainage Hydrological study :‐To determine amount of water Hydraulic study :‐To design the drainage facility Calculating cross sectional area, depth of flow and velocity of flow in drainage Hydrological study Precipitation: Rain, Hail, or Snow Important – Rainfall intensity: i ( is found in mm/sec). corresponding to rainfall duration T and the return period .reading from graph Runoff : difference b/n amount of rainfall and loss due to infiltration, evaporation , transpiration, interception, & storage 5/30/2024 65

64. Hydrological Analysis Main Objectives: To Estimate the Maximum Quantity of Water (Qmax) Expected to Reach the Element of Drainage System Under Consideration. Various Factors Affecting the Run-off are Rate of rainfall, Types of soil and moisture condition, Topography of the area, Type of groundcover.

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81. Surface drainage systems…Design Structural design of the cross drainage structures involves two steps: 1)analysis of loads on structures Pressure due to external loads a) Overburden pressure (vertical stress) on the culvert:   is the pressure exerted by layers of soil above culvert b) Traffic loading Boussinesq’s Equation: 5/30/2024 83

82. Surface drainage systems…Design 2) designing adequate structural member for the analyzed load … material and Thickness selection ….Comparing the computed stress with allowable stress value for structure type 5/30/2024 84

83. SUBSURFACE DRAINAGE Subsurface drainage systems are provided with in the pavement structure to drain water in one or more of the following forms: Water that has permeated through cracks and joints in the pavement to the underlying strata. Water that has moved upward through the underlying soil strata as a result of capillary action. Water that exists in the natural ground below the water table , usually referred to as ground water. 85

84. Cont … The subsurface drainage system must be an integral part of the total drainage system, since the subsurface drains must operate in consonance with the surface drainage system to obtain an efficient overall drainage system. The design of subsurface drainage should be carried out as an essential part of the complete design of the road , since inadequate subsurface drainage also may have detrimental ( tending to cause harm) effects on the stability of slopes and pavement performance. 86

85. Effect of Inadequate Sub drainage The effects of inadequate sub drainage fall into two(2) classes: Poor pavement performance If the pavement structure and subgrade are saturated with underground water, the pavement's ability to resist traffic load is considerably reduced, resulting in one or more of several problems, When asphaltic concrete pavements are subjected to excessive uncontrolled subsurface water due to inadequate sub drainage, very high pore pressures are developed within the untreated base and sub base layers resulting in a reduction of the pavement strength and thereby its ability to resist traffic load. 87

86. In Portland cement concrete pavement, for example, inadequate sub drainage can result in excessive repeated deflections & Pumping of mud in Rigid Pavements which will eventually lead to cracking. Slope Instability The presence of subsurface water in an embankment or cut can cause an increase of the stress to be resisted and a reduction of the shear strength of the soil forming the cut . This can lead to a condition where the stress to be resisted is greater than the strength of the soil, resulting in sections of the slope crumbling down or a complete failure of the slope. 88

87. Cont.… Subsurface drainage systems are usually classified into five general categories: 1.Longitudinal drains Subsurface longitudinal drains usually consist of pipes laid in trenches within the pavement structure and parallel to the center line of the highway. These drains can be used to lower the water table below the pavement structure, 2. Transverse drains Transverse drains are placed below the pavement, usually in a direction perpendicular to the center line, although they may be skewed to form a herringbone. 3. Horizontal drains Horizontal drains are used to relieve pore pressures at slopes of cuts and embankments on the highway. They usually consist of small diameter, perforated pipes inserted into the slopes of the cut or fill . The subsurface water is collected by the pipes is then discharged at the face of the slope through paved spillways to longitudinal ditches. 89

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89. Cont’d 4. Drainage blankets A drainage blanket is a layer of material that has a very high coefficient of permeability, usually greater than 30 ft /day, and is laid beneath(under) or within the pavement structure such that its width and length in the flow direction are much greater than its thickness. 5.Well systems A well system consists of a series of vertical wells, drilled into the ground, into which ground water flows, thereby reducing the water table and releasing the pore pressure. 91

90. Cont.… The design procedure for subsurface drainage involves the following. 1. Summarize the available data. 2. Determine the quantity of water for which the sub drainage system is being designed. 3. Determine the drainage system required . 4. Determine the capacity and spacing of longitudinal and transverse drains and select filter material, if necessary. 5. Evaluate the design with respect to economic feasibility and long-term performance. 92

91. THANK YOU !! 5/30/2024 93