How do you find the chainage of a tangent point?

How do you find the chainage of a tangent point?

5) The chainage of T1 is obtained by subtracting the tangent length from the known chainage of the intersection point B. And the chainage of T2 is found by adding the length of curve to the chainage of T1. 6) Then the pegs are fixed at equal intervals on the curve.

How do you calculate PC and PT?

After the length of the curve (L) and the semi-tangent length (T) have been computed, the curve can be stationed. When the station of the PI is known, the PC station is computed by subtracting the semi- tangent distance from the PI station. (Do not add the semi-tangent length to the PI station to obtain the PT station.

What is a PI station?

The intersection point of a horizontal curve is defined as the Point of Tangent Intersection (PI). By definition, PIstation = PCstation + T. Because the PI station is calculated in this way and the horizontal tracking is calculated along the length of the curve, the two values will differ.

What is the chainage formula?

The formula is Q = X * I * I, where X is the reactance of the circuit, I is the current through the circuit.

What is a chainage equation?

Chainage equations give the user the ability to change the chainage at any key point along a primary alignment. The user can place any number of chainage equations within an alignment. Chainage equations can be used to either increase or decrease the chainage at a nominated point.

When both PT and PC is inaccessible?

When the PC is inaccessible, as illustrated in figure 7, and both the PI and PT are set and readily accessible, the surveyor must establish the location of an offset station at the PC. Place the instrument on the PT and back the curve in as far as possible.

What is pi station?

How do you subtract station numbers?

To find the distance between any two stations (except where station equations or equalities are involved) simply subtract the lower station from the higher one, ignoring the plus sign. You will get the answer in feet. On the Plan Sheets, the Station Numbers are usually written along the Survey Line.

What is the length of tangent from PC to Pi called?

Also called vertex T = Length of tangent from PC to PI and from PI to PT. It is known as subtangent. R = Radius of simple curve, or simply radius. L = Length of chord from PC to PT.

What is a chainage?

The word “chainage” as used today indicates the centerline of a linear structure, such as a road or pipeline. It’s used in conjunction with “elevation” and “offset” to draw up construction plans.

What is the length of a chainage survey?

A “chain” is used as a unit of measure, equaling 22 yards (66 feet), which was the length of Gunter’s chain. While the old chainage method is antiquated, surveyors such as Votex Surveying Company still use chainage as part of construction surveys today.

How do you find the PT station from the Pi station?

When the station of the PI is known, the PC station is computed by subtracting the semi- tangent distance from the PI station. (Do not add the semi-tangent length to the PI station to obtain the PT station. This would give you the wrong value) Once the PC station is determined, then the PT station may be obtained by adding L to the PC station.