*Step-by-step work through on earth volume computation using sufer*

*Step-by-step work through on earth volume computation using sufer*
The procedure assumes you already have sufer installed on your PC
👉Launch the sufer application by double clicking its icon on your desktop
👉On the program main menu, click Grid
👉Click data... in the drop down sub-menu
👉Navigate and locate the raw file containing your x,y,z data defining the surface in question
👉Click Open
An interface showing some sample of your data is displayed on the screen
👉Ensure that the appropriate field delimeter is selected and click OK
👉On the Grid Data interface that comes up next, select the appropriate field (i.e column) for each of your x, y, z data as contained in the previous interface
👉Select any desired griding method on the space provided for such on the Grid Data interface. The common and default method is kriging
*Note* : the result you obtain depends pretty much on the grid method you select as each of the methods uses different models in predicting the Grid elevation of the unobserved points
👉Click OK
The griding is then carried out by the application and the report displayed on the screen that can be saved to a file
*Note:* These procedures applies for each of the surfaces in the case of two surfaces volume computation. For a single surface, you just do that once for the available surface file

Next is to compute volume using the grid file created
👉On the program main Menu, click Grid
👉Click Volume in the drop down menu
👉Browse and locate the grid file created
👉Click to open the file
👉The Grid Volume interface pops up where you are expected to define your surfaces
👉The upper surface is natural ground surface (Topo-surface) for which a grid file has been created
👉The Lower surface is the grade or design surface
👉 For each of the surfaces, you can either chose to load a grid file or use a constant value
👉For a single surface volume with only the natural ground grid surface elevations, click and upload the grid file for the upper surface and define a constant, z value for the lower surface   (graded surface)
👉 Leave the Z- factor as 1
👉Click OK
The cut and fill volumes are displayed with the associated areas obtained

*Note*: the results earth volumes may vary from one application to another even with the same data depending on the method for computing areas and of course the griding method

How to Measure Angles Using a Theodolite - Part 2 Taking a measurement

How to Measure Angles Using a Theodolite

A theodolite is an instrument used commonly by builders and engineers to measure precise angles, which is necessary for large scale construction projects. A basic modern optical theodolite typically consists of a small telescope which is connected to two angle measuring mechanisms, one for measuring horizontal angles and one for measuring vertical angles. It sits atop a rotatable base with a leveling mechanism on a tripod. Once the theodolite is set up, the telescope is turned to spot the desired point and then the angle from the point that the theodolite is placed to the point spotted in its telescope can be read through the eyepiece of the scope.

Taking a measurement

Step 1

Unlock the upper horizontal clamp, and rotate the theodolite until the arrow in the rough sights is lined up with the point you wish to measure, then lock the clamp. Use the upper horizontal adjuster (not the clamp) to align the object between the two vertical lights in the sight.

Step 2

Look through the small eyepiece, and using the fine adjustment knob to get a precise horizontal line up with your object. The degrees from your reference are measured on the horizontal degree scale, the minutes and seconds on the fine adjustment scale (ex. 30 degrees 10'30").

Step 3

Unlock the vertical clamp and look through the sight while moving the theodolite up and down to find the precise spot vertically on your object that you'd like to measure. Lock the clamp and use the fine vertical adjustment knob to get a precise fix on the point you've chosen. Then look through the small eyepiece and read off the degrees, minutes and seconds from the vertical scale and the fine adjustment scale as you did for the horizontal scale. If your object is up high you'll need to do a rough horizontal adjustment first, then do the vertical measurement, then readjust for the final horizontal measurement. These two coordinates give the exact angle between your reference and your point of interest, but you can also measure the angle between two points by comparing their two measurements, or by setting the first point as the reference.