Starting a course on Surveying?

New second edition is now in full colour making it even easier to understand the techniques used by surveyors. 

Ideal for anyone studying for:

• BTEC (EdEXCEL) National or Higher National in Construction or Civil Engineering. 
• City & Guilds: Construction [Level5]
• Degree level: First year Surveying

The emphasis is on fully explaining the various processes used by surveyors including:

• techniques 
  
• practical help
• safety issues
• the math's side with fully worked examples

Written in plain English with plenty of graphics. Even complicated operations such as closed traversing, setting out for roads, and for framed buildings have been explained.

A5 size 204 pages.            ISBN: 978-1-9993109-5-0

Levels, Theodolites & Total Stations

Levels, theodolites, total stations and reflectors

all require fine adjustment to ensure they are

level after attaching them to a tripod.

There are several designs of instrument:

Some have a simple spirit bubble on a plate

Some have a circular bubble commonly referred

to as a 'Cat's eye' level bubble

There are the older 'dumpy' levels that have a polished metal plate set at  a 45° angle above the bubble. It allows the surveyor to check the instrument for level just before taking a reading

Modern instruments may have digital bubbles.

The technique for levelling them up is the same.

One exception is the 'quick set' or 'engineers level'

Closed Traversing

Measuring for a new shopping complex or a large plot of land is easier using a closed traverse technique. In principle the theory is very simple.

A series of stations are set up and distances and angles are measured in relation to each other.

In practice it requires the surveyor's skill and accuracy.

The whole process is explained including a worked example and all the maths involved.

There are situations when a closed traverse

cannot be used. An open traverse may be more suitable. The method used and the whole process is explained..

Whole Circle Bearings (Wcb)

 and Quadrant bearings (QB)

An important part of converting the measured

data from the traverse is to compare all of the stations with a known point.

It can be magnetic north, or a part of a building

in the distance referred to as a 'Reference Object'  (RO).

The process is fully explained including all of the

maths required.

A fully worked example from booking to conversion into coordinates has been shown. It also includes the necessary adjustments.

Conversion of Wcb to Coordinates

The maths required is basic trigonometry. Although fully worked examples have been shown,  additional information about the maths used is in: Construction Math's Explained

Total Stations can be programmed to record

all the data gathered.  The data format can be

in degree radians as a decimal. Sine radians, Cosine radians or Tangent radians.

How to enter raw data onto a spreadsheet

with the formulae to convert it is also shown

in the maths book.

Levelling

There are two main methods of recording the differences between levels:

1. Rise and Fall method
2. Height of Collimation method

Both methods are fully explained including how to read a surveyor's 'E' staff. 

The method used for transferring levels from say an 'invert level' to a 'TBM'. All of the terms are fully explained.

When measuring levels such as the soffit of a canopy, or tunnel roof, 'inverse levelling' is required. It is fully explained including easy to follow graphics.

Levelling terms

Back sights, Fore sights, Intermediate sights, Invert levels, Inverse levels, Reduced levels, Change points, Height of Collimation, Line of Sight, HOC, LoS, BSs, ISs, FSs. 

All very good if you know what they all mean?

All the terms are explained fully including graphics when required.

Worked examples of both the Rise and Fall method and the Height of Collimation method including how to book the readings and carry out the checks.

Which booking method is best?

Both methods; R&F and the HOC methods

have advantages and disadvantages. It is

good practice to be able to do both.

The same example has been used for both methods so that a comparison can be seen.

It is important to carry out the checks whilst

still on-site. If the checks do not match then inspect the data for any obvious errors, or

do the survey again.

Digital Levels

Levels have come a long way from the old 'dumpy levels' and 'Cowley levels'. The modern automatic digital levels are still based on a telescope with 'stadia lines'.  The surveyor uses the stadia lines to  target the object and then send out a laser beam that very accurately records the data.

When used with a 'bar code' staff the instrument records the precise difference in height from the 'reduced level' to the 'line of sight'. The book fully explains the methods used and what the terminology means.

The latest models from Leica Geosystems are  programmable via a keypad and icon led screen.  An exceptional piece of kit that requires a 'course' on how to use its many functions. However, how to set the instrument up and adjust for parallax and focusing is the same as any other level.

Drainage runs

Commonly used in Civil Engineering projects.

The task from the initial survey through to

setting up of sight rails is explained.

The calculations from outfall to peak are

shown on a typical form with explanations of where the figures come from.

The setting up of sight rails, the coding used and the levels that enable excavations to be carried out are shown.

Setting out

Smaller buildings such as houses that have

trench foundations require profile boards to

be set up.

The whole process from the initial setting out

a building line has been described and shown graphically.

Setting out for loadbearing internal partition

walls and 'wants' has been included. Plus the checks that should be carried out.

Setting out for framed buildings

Completely different techniques are used

to set out for a large framed structures.

From the initial setting up of a TBM through to marking out for a pile driver or series of pads

is explained in detail.

Not strictly surveying it is important to know

how the setting out will be used.  The short

length of rebar, the shuttering boxes, the

holding down bolts. Even how the voids are

formed to allow for small adjustments. 

All based on site experience it completes the whole picture of setting out.