The entry of the point description is optional.Home > Survey Mode > Reductions > Levelling > Fieldbook > New Field Book
Open a new, blank spreadsheet for Levelling data.
Levelling data can be typed directly into the spreadsheet. Each line of the spreadsheet represents either a change point or an intermediate point.
Each type of entry has different requirements. All entries require at least a field book indicator code (see below) and a point name or descriptor.
Change points also require a back sight and/or fore sight reading.
Intermediate points also require an intermediate reading.
Permissible field book indicator codes are:
c - Changed point.
The order of the data fields is:
Observation code
Back sight
Intermediate sight
Fore sight
Point name
An example of the normal field book format is given below:
c,2.094,0.000,0.000,MR11
i,0.000,1.580,0.000,60
i,0.000,1.171,0.000,70
c,0.635,0.000,1.284,MH1
c,4.510,0.000,0.660,
i,0.000,0.510,0.000,80
c,0.000,0.000,2.682,MR12
The first line represents the start of the run, which is also a Change Point, and denoted by "c".
The following two lines are Intermediate readings denoted by "i".
Two Change Points (c) follow these, another Intermediate reading (i) and the final Change Point (c) indicates the end of the traverse.
The entry of the point description is optional.
Spirit levelled cross-sections are a special case of levelling. The field book for levelled cross-sections has the same format as the normal level field book with a few additional features.
You can optionally specify codes and offsets in the first few rows of the spreadsheet for the points to the left and right of the centre line. Should the values (offsets) of the codes change, the changed values have to be entered in the spreadsheet (in the same way as described below) before these codes are used. These values may be changed as many times as desired, as long as the new values are entered for each change. Allowed values for codes are A - Z and a - z. A maximum of five is allowed on each side of the centre line.
An example in text form is given below:
A,,-6.5,,,
B,,-3.5,,,
C,,0,,,
D,,2,,,
E,,4,,,
c,2.094,0.000,0.000,BM206
#,0.000,0.000,0.000,24120
i,0.000,1.568,0.000,C
i,0.000,2.690,0.000,B
i,0.000,2.100,0.000,D
i,0.000,2.320,0.000,A
i,0.000,1.580,0.000,E
c,0.635,0.000,1.284,
#,0.000,0.000,0.000,24200
i,0.000,0.889,0.000,C
i,0.000,0.980,0.000,A
i,0.000,1.160,0.000,B
c,4.510,0.000,0.660,
i,0.000,0.740,0.000,D
c,0.000,0.000,0.640,E
The '#' is used to denote a chainage value that is set in the comment field. All the readings following a '#' are applied to that cross-section until another '#' is read and that section then becomes the current cross-section.
The 'Change Points' ('c') and Intermediate readings ('i') are similar to a normal level traverse, except that the comment can be used to either specify an offset directly or have a single character conversion code. In the example, line 5 has a comment of 'D' and therefore, in the reductions, an offset of 2.0 will be added to the section at chainage 24120.
The section observations can be taken in any order and there is no need to complete any one section before starting the next. In fact, it is often convenient to complete the whole of one side of a road in one direction before levelling the other side on the return. This is quite acceptable, as complete sections are built from whatever data is found.