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What are today’s objectives ?. Increase understanding of Paydirt Sitework. How Sitework uses the grid cell method. How data types affect surface modeling. How to get the information you need. How to combine a multiple sheet take-off. What will we be doing ?. Pre-Assessment
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What are today’s objectives ? • Increase understanding of Paydirt Sitework. • How Sitework uses the grid cell method. • How data types affect surface modeling. • How to get the information you need. • How to combine a multiple sheet take-off.
What will we be doing ? • Pre-Assessment • Sitework’s use of the Grid Cell Method. • How each data type affects the grid. • Specific Takeoff Situations • How to use the Cut/Fill Location Report. • How to produce a stake out report for field use.
Calculating Cut / Fill Volumes • Must create a model for each Surface. • Existing Surface Model. • Proposed Surface Model. • Each model must be adjusted to subgrade. • Compare the 2 models to get cut / fill volumes. • More accurate models yield more accurate results.
Basic Steps of Manual Gridding • Overlay or draw a grid on the site plan. • For each surface • interpolate elevations for all grid intersections. • calculate the average elevation of each grid. • Calculate volume of cut or fill in each grid. • Add up the cells to get the total cut / fill.
Sitework's Implementation of the Grid Cell Method. • User inputs data for each surface. Sitework • Defines the grid rectangle. • Places data onto the grid. • Calculates the affect of the data. • Smoothes the surface. • Adjusts the grid for enclosed areas. • Calculates volumes based on the Area of Interest.
Sitework’s Data Types • Areas of Interest • Boreholes • Contour Lines • Control Points • Cut Stakes • Elevation Points • Layers • Sloping Areas • Sloping Lines • Structures
Surface data types • Define Sitework’s data types • What data types affect the grid • What data types do not affect the grid • What data types work together • When to use the different data types
Data Types that DO NOTaffect gridding • Area of Interest • Determine cells to be used for calculating volumes. • Do not affect how elevations are assigned to grid intersections. • Control Points • Allows the coordinate system to be redefined. • No direct affect on the gridding process. • Cut Stakes • Provide Information specific site locations.
Areas of Interest (AOI’s) • Define a boundary for volume calculations. • Have no elevation. • Must be enclosed. • Data can be entered outside an AOI. • Data outside an AOI is used for surface model. • Master AOI is default for volume calculations. • Master AOI is critical for accurate volumes.
3 Categories of Surface data • Line data • 2 or more digitized points. • 1st and last points do not have to meet. • Point data • 1 digitized data point. • Enclosed Data • 1st and last point must meet (minimum of 3 points). • have no affect outside their boundary.
Line data Data types • Contour lines • Sloping lines Properties • Assigned to a series of grid intersections. • Creates a wall of data. • Influences grid on both sides of line.
Point data • Data types • Elevation Points • Boreholes • Properties • Consists of 1 digitized data point • Assigned to 1 grid cell intersection
Line & Point data work together • Grid is built from line and point data. • Line & point data is placed on the grid & assigned to grid intersections. • Unassigned intersections are interpolated from line & point data. • All grid intersections are given an elevation based on line and point data.
Enclosed Areas • Data Types • Layers • Sloping Areas • Structures • Properties • Have no affect outside their boundary. • Affect takes place after the grid has been built. • Make adjustments to the grid.
Enclosed Areas adjust the grid • Effect on grid takes place after grid is built. • Marks intersections affected by enclosed area. • Adjust the grid for affected intersections only. • No grid cells outside an enclosed area boundary are adjusted.
Structures • Define an area to be perfectly flat. • Contours, Sloping Lines, Elevation Points • do not affect the elevation of a structure. • their affect takes place during the grid generation. • Replace intersection values with structure elevation. • Have no affect outside their boundary.
Contour #1 / Structure A A’ B B’
Contour Structure
Sloping Areas • Could be called Sloping Structures. • Have a uniform slope. • They cannot bend. • Slope % = % of grade (50% = 2:1). • Have no affect outside their boundary.
Layers • Have no elevation. • Adjust the grid by their thickness. • Thickness is subtracted from affected intersections. • Do not alter the slope of a site. • Have no affect outside their boundary. • Stacked Layers accumulate.
More Preferences in Sitework • Layers under structures (Two Choices) • affect subgrade • do not affect subgrade • Layers affect subgrade • Layers lower elevations under structures & slope areas • Layers Do not affect subgrade • Layers do not lower the site under structures or sloping areas
Layers affect subgrade under Structures Layers affect subgrade • Structures are first enclosed area placed on grid. • Sloping Areas are second. • Layers are last. • If Sloping Area overlaps a structure the sloping area takes precedence. • Layers will adjust grid by thickness after the affect of Structures and Slope Areas has happened. Layers do not affect subgrade • Layers first, Sloping Areas second. then Structures. • Sloping Areas and Structures cancel the affect of a layer they overlap when placed on grid. • If a Structure and a Slope Area overlap the Structure takes precedence. • Enter elevation at subgrade or use thickness to adjust to subgrade for both Structures and Slope Areas. • Can still use layers to separate material volumes.
Contour and a Contour Contour 100 Contour 100 Contour 90 Contour 90 The situation where the contour lines overlap is a problem because the 100 affects inside the square and the 90 affects outside.
Contour overlapping a Structure Contour 100 Contour 100 Structure 90 Structure 90 This situation is not a problem because the contour’s effect occurs before the structure is placed on the grid, so the area stays flat.