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Grade rods are graduated in feet, tenths, and hundredths of feet. The rod is used to determine differences between ground elevations at two points. A level of some kind is necessary.
You start from a point of known elevation or height, for example, the point along a road under construction where a cut slope will intersect the ground surface. That point will be shown on the plans and cross sections, and will be established by surveyors in the field. Usually they will pound a stake in the ground and the actual catch point will be a nail with whiskers. To check the elevation difference between that point and some other point (let's say, the point on the ground directly above where the road centerline will be) you need to occupy the lowest point with the grade rod. What you do is sight along a level line (usually with a hand level, held against the grade rod) to the point that is higher. You move up and down the grade rod until the level line of sight hits the point of known elevation -- or a point of known distance above the known point (which you can establish with a piece of survey lath, a measuring tape and a magic marker).
Let's say you are on the side of a hill and the cut slope stake is up there someplace, indicating what the vertical distance (cut) will be between that point and centerline. You don't make the vertical cut there, of course, you make the cut above centerline. But at centerline the ground surface is lower so in order to know what to cut, you need to know how much lower the ground surface is. You occupy the centerline with the grade rod, holding it vertical. You get out your hand level and, holding it against the grade rod, find the cut slope stake at ground level (or the point of known vertical distance you marked on the lath above it). You move the hand level up and down the grade rod, maintaining it level, until you are sighting that point at the cut stake. Then the number opposite the hand level on the grade rod is the elevation difference between the point you are occupying at centerline and the point you are shooting to. If you were at 6.3 ft on the grade rod and you shot to a point 2.5 ft above the catch point nail, the elevation difference between the ground where you were and the catch point is 6.3-2.5=3.8 ft. So whatever the stake says the cut to centerline is, you can subtract 3.8 ft because the ground above centerline is 3.8 ft less than it is where the stake is.
You occupy the low point with the grade rod, because you have to shoot along a level line to a higher point. If the point you are shooting to is to high to get to in one shot, you do it in steps and add them up.
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How do you shoot grades from a bench mark?
Set up the instrument. Get it level. Shoot the gradestick. Know what the actual elevation is. Subtract the actual elevation of the grade you want from the elevation of the benchmark. Add the amount you shot on the stick at the benchmark to the amount you deduced. Shoot the stick at the point you want, and tell your helper to move the stick up and down till you get the right # in your sights. Pretty simple once you get the hang of it. I'm 19 and can do it so...
What is the instrument used to measure the elevation?
The instrument used to measure elevation is called an altimeter. It works by measuring air pressure changes as altitude changes, providing a rough estimate of elevation above sea level.
What is a DIY method to calibrate a tripod mounted transit level or check it for accuracy?
To check for accuracy, set up water level, then shoot the ends.
When was Transit Transit created?
Transit Transit was created on 2010-08-03.
How far will a sks rifle shoot?
The EFFECTIVE range is about 400 meters. If fired at an optimal angle of about 30 degrees of elevation, it will travel about 3123 yards or about 1.77 miles, but it will not be accurate.
When was Grossmont Transit Center - MTS Transit Center - created?
Grossmont Transit Center - MTS Transit Center - was created in 1989.
How do you calcuate height of instrument in surveying?
When surveying using a "level" instrument , the "level" instrument is set-up and adjusted to level by adjusting the screws. When surveying you have an instrument person and a rod person. When trying to find the height of the instrument, the rod person places there rod over a "known" elevation, either a benchmark or a temporary benchmark that has a known elevation. To get the height of the instrument, you need to "shoot" the level to the rod person holding the rod on the known elevation, this is called the "Backsight". This elevation will be read by the instrument person, and recorded in the survey field book. This value backsight elevation will then be added to the known elevation of the benchmark or the temporary benchmark, to get the height of instrument. HI = known elevation + BS Height
Cash in transit insurance from where the transit starts and what is the insurance meaning of transit?
Insurance meaning of transit is the common meaning of the word i.e. journey from one place to other. In case of Cash in transit, the insurance attaches during transit i.e. transit start and end as specified under the schedule of policy.
Who invented electric transit?
Who invented thd Electric Transit? What year was the Electric Transit invented?
When was Fashion Valley Transit Center - MTS Transit Center - created?
Fashion Valley Transit Center - MTS Transit Center - was created in 1997.
How do you use a transit to shoot a grade?
Today someone came to my home because of a drainage problem I have. He said, "shoot it to get a grade". It means use a surveyors transit tool to get an accurate level of the ground so that the water can follow better. Ok, everybody that slept through geometry class. A transit is a very sensitive instrument which can be leveled very accurately and can measure angles very precisely, both horizontally and vertically. The surveyor will mark two points on the ground, in the case of a drainage problem probably near the highest and lowest parts of the property. He will then set his transit up directly over one of the points, and will use the levels in the instrument to make sure that the instrument is precisely level. He will then aim the telescope at the second point on the ground and will use the internal scale to read off the "vertical angle" which is the angle above or below horizontal. In an old-fashioned instrument, he will next use a tape measure to measure the distance between the telescope and the point at which he is aiming. In a modern device, a reflector will be placed at the second point, and the transit will measure the distance using a laser device. The surveyor will also measure the distance the center of the transit is above the first point. Using trigonometry, he can then calculate the exact difference in elevation between the two points, and consequently the likelihood that water will drain from the higher to the lower point. If there are further points to be measured, the transit is rotated from one point to another, recording the exact angle turned in each case. Further trigonometry can then be used to calculate the precise location of the remaining points and their relationship in three dimensional space. If the idea is to lay out a pre-determined grade, trigonometry is used to establish the vertical distance necessary to attain the desired grade at the measured distance, and the correct elevation can be marked on a vertical surface. Everyone should take first year engineering.
What is the type of theodolite?
Transit and non-transit theodolite.
