Mass curve Figure 2.23: Length Profile and similar mass and mass diagram of a road section. Figure courtesy of Bent Thagesen: Lærebog Veje & Stier. The mathematical fill volumes must be corrected by multiplying by the compression factor. Mass curve indicates a graphic overview of soil moving amounts within in the whole road. It indicates how much soil to be dug or back filled in each section, e.g. between compensation points. The ideal mass curve has many countervailing points along the way, since this means short transport distances, and usually it is small soil masses moved. Closes mass curves not at the end, there is either a surplus or deficit of soil. When consideration a mass curve one should not be confused by the fact that it always starts at 0. It is the effect of the summation that starts at this point. Similarly, the fact that a surplus or deficit of soil evident by the mass curve does not close at the end, does not mean that it is precisely here that the surplus or deficit arises. The actual construction of the mass diagram is performed as follows: Apart from road profile determined with fixed stationing intervals an array of sections whose filling and excavation intervals calculated. Multiplied by interval length often set to 20 m one gets how many cubic meters of soil to be side moved, added or removed within each stationing interval. The result of a soil calculation can be expressed as in Example 2.01. Example 2.01: Soil calculation. Here is side moving the amount of soil to be moved within a stationing interval, while the mass curve formed by the summation of the resulting soil volumes to be removed or added stationing intervals. Mass curve ordinate M = S resulting excavation volume X resulting fill volume. At the mass curve, Figure 2.24, you can learn for example that between A and B shall dredged a certain amount of soil equal to the height difference hab. The equivalent soil amount shall be filled with area CD, i.e. moving becomes a trapezoidal area between AB and CD. Moving Average distance for all soil works from A to B can either be evaluated graphically or calculated as a mass curve area with longitudinal axis divided by the maximum ordinate equivalent to the equates mass curve with a rectangle of the same area.
Mass curve Figure 2.23: Length Profile and similar mass and mass diagram of a road section. Figure courtesy of Bent Thagesen: Lærebog Veje & Stier. The mathematical fill volumes must be corrected by multiplying by the compression factor. Mass curve indicates a graphic overview of soil moving amounts within in the whole road. It indicates how much soil to be dug or back filled in each section, e.g. between compensation points. The ideal mass curve has many countervailing points along the way, since this means short transport distances, and usually it is small soil masses moved. Closes mass curves not at the end, there is either a surplus or deficit of soil. When consideration a mass curve one should not be confused by the fact that it always starts at 0. It is the effect of the summation that starts at this point. Similarly, the fact that a surplus or deficit of soil evident by the mass curve does not close at the end, does not mean that it is precisely here that the surplus or deficit arises. The actual construction of the mass diagram is performed as follows: Apart from road profile determined with fixed stationing intervals an array of sections whose filling and excavation intervals calculated. Multiplied by interval length often set to 20 m one gets how many cubic meters of soil to be side moved, added or removed within each stationing interval. The result of a soil calculation can be expressed as in Example 2.01. Example 2.01: Soil calculation. Here is side moving the amount of soil to be moved within a stationing interval, while the mass curve formed by the summation of the resulting soil volumes to be removed or added stationing intervals. Mass curve ordinate M = S resulting excavation volume X resulting fill volume. At the mass curve, Figure 2.24, you can learn for example that between A and B shall dredged a certain amount of soil equal to the height difference hab. The equivalent soil amount shall be filled with area CD, i.e. moving becomes a trapezoidal area between AB and CD. Moving Average distance for all soil works from A to B can either be evaluated graphically or calculated as a mass curve area with longitudinal axis divided by the maximum ordinate equivalent to the equates mass curve with a rectangle of the same area.
Book%202%20-%20Soil%20work%20February%202013%20version%201%201.docx