Homework For Dumbies

Index

http://mardz2.tripod.com/id15.html for d image

Introduction
Civil engineering is one of the oldest forms of engineering and it is with great enthusiasm that I am able to learn this complex study at the University of San Carlos in Guatemala City. My job now consists of learning every way possible to become the best engineer I can be. One of the ways in which I plan to achievethis mission is to advance in any way possible and with my knowledge of the English language I have been given an opportunity to advance such a class. The challenge will be to actually learn all I can on the topic at hand. I look very forward to achieving this goal and I hope to use this book as a medium to help not only myself but also my peers.

Objectives:
* To help the reader have a clearidea of what topography is.
* To help understand how to take care of the optical theodolite.
* To explain how to use every single part of the optical theodolite.
* To learn how to setup, check and adjust the optical theodolite.

Theodolite’s Handbook
Topography
* Is the study of the Earth's surface. The shape and features or those of planets, moons, and asteroids. It is isalso the portrayal of such surface shapes and features.
* In a broader sense, it is considered with local detail in general. This includes vegetative and human-made features, and even local history and culture.
* In America "topography" is a synonymous with relief.
* However in Europe the older sense of topography is still known as the study of place.
* It also involves therecording of relief or terrain, the three-dimensional quality of the surface, and the identification of specific landforms.

i. Parts of a theodilte:

ii. How to set up a theodolite on a tripod:
First extend the tripod legs, splay them fully and push the ends firmly into the ground. Next look at the Theodolite mounting platform. This should be reasonably level and not too high nor too lowfor the users. Adjust the leg lengths until it is right then screw the theodolite onto the platform.
iii.
iv. You may wish to set the theodolite up over a reference point on the ground. In this case, you can use the sight (F) on the front of the instrument to view the point and adjust the theodolite’s position by slightly unscrewing the mounting screw and moving the theodolite sideways.Alternatively, you can ask a helper to push a nail or peg into the ground under your guidance to fix a new reference point.
v.

Extend the tripod legs to a proper length (around shoulder height), and set the tripod approximately over the marked survey point. The tripod head should be levelled (use horizontal objects as references), and each leg should make approximately a 70 angle with theground. Feel free to lift the tripod and redo the above if necessary. Avoid having a tripod leg coming at you; that might cause some inconvenience.
Carefully take the theodolite out of the carrying case, and remember how it was fitted in the box so that you know how to put it back later. Mount it on the tripod, and fasten the tripod screw. Make sure the tribrach base and the tripod head (bothtriangular) are parallel and share the same centroid to permit maximum translation in any direction, which will be needed later on. Remove the lens cap, put it back into the carrying case, and close the box.

The way how the optical theodilites works is that both axes are equipped with graduated circles that can be read through magnifying lenses. The vertical circle which 'transits' about thehorizontal axis should read 90° (100 grad) when the sight axis is horizontal, or 270° (300 grad) when the instrument is in its second position, that is, "turned over" or "plunged". The “index error” is known as half of the difference between the two positions. Both the horizontal and vertical axes of a theodolite must be perpendicular if this is not so then a "horizontal axis error" exists. Testing...