FREE NCEES Civil Surveying Questions and Answers

Question 1

Differences between the projected contour gradient uphill side and the actual road gradient include

Accepted Answer

Excavation on the centre line

Answer

When the projected contour gradient on the uphill side of a proposed road differs from the actual road gradient, it indicates a discrepancy between the natural ground level and the design level. If the natural ground is higher than the desired road profile, material must be removed from the center line to achieve the correct gradient. This process of removing earth is known as excavation.

Question 2

A plane table's "fix" from three known locations is good if

Accepted Answer

Middle station is nearest

Answer

In plane table surveying, determining a point's position (a 'fix') from three known stations involves drawing rays from each station towards the unknown point. A 'good fix' is achieved when the middle station among the three known points is nearest to the unknown point. This geometric arrangement minimizes the 'triangle of error' formed by the intersecting rays, leading to a more precise and reliable location for the fixed point.

Question 3

Using a chain line, you may create a 45° angle with

Accepted Answer

French cross staff

Answer

A French cross staff is a specialized surveying instrument used to set out specific angles in the field, particularly multiples of 45 degrees. Its design, often octagonal with sighting slits, allows surveyors to accurately establish angles such as 45°, 90°, and 135° directly. This makes it suitable for creating a 45° angle with a chain line, unlike other cross staffs that typically only set out 90° angles.

Question 4

Which of the following errors/mistakes may add up to + or -?

Accepted Answer

Erroneous length of chain

Answer

An erroneous length of chain is a systematic error in surveying, meaning it consistently affects measurements in a predictable direction. If the chain is too long, all measured distances will be recorded as shorter than their actual length, leading to a cumulative negative error. Conversely, if the chain is too short, measured distances will be recorded as longer, resulting in a cumulative positive error. This type of error can therefore add up as either positive or negative depending on the chain's deviation.

Question 5

Correction for a chain of 100 links with a rise of 1 unit every n horizontal units is

Accepted Answer

100/n2

Answer

The correction for slope in chaining, often called hypotenusal allowance, accounts for the difference between the measured inclined length and the true horizontal length. For a slope where there is a rise of 1 unit for every 'n' horizontal units (i.e., a slope of 1 in n), the approximate correction for a measured length L is given by L * (slope)^2. If the slope is 1/n, the correction is L * (1/n)^2 = L/n^2. For a chain of 100 links, the correction becomes 100/n^2.

NCEES National Council of Examiners for Engineering and Surveying Practice Practice Test

NCEES National Council of Examiners for Engineering and Surveying Practice Practice Test

FREE NCEES Civil Surveying Questions and Answers