BSV07102 Surveying 1 COURSEWORK 2

BSV07102 Surveying 1

COURSEWORK 2

Q 1 Two existing manholes, A and B are to be connected by a sewer. The plan length AB is 140.000m

The line of the sewer was established by means of pegs at 20m intervals. The peg tops were levelled by taking a run of levels starting on TBM1 and finishing on TBM2. The results are shown in Table Q.1. The excavation for the sewer is to be monitored using profiles and a 2.5m traveller.

• Draw up a suitable level book page and reduce the levels carrying out relevant arithmetic checks. (10)
• Calculate the gradient of the pipe.                                                         (3)
• Calculate the required heights of the profiles above the tops of the pegs. (4)

(Total 17)

 

BS	IS	FS	Distance from Manhole A	Remarks
1.926				TBM1 (RL 95.249 AOD)
	2.989		0	Invert manhole A
	1.744		20	Top of Peg 1
1.308		1.873	40	Top of Peg 2
	1.481		60	Top of Peg 3
	1.746		80	Top of Peg 4
0.924		2.088	100	Top of Peg 5
	1.062		120	Top of Peg 6
	1.598		140	Invert Manhole B
		2.206		TBM 2 (RL 93.240m AOD)

Table Q 1

Q.2

An anti-clockwise closed traverse 9, 10, 11,12,9 was used as the controlling framework for a topographical survey of a small area of ground.

Table Q.2 provides details of the horizontal angle measurements recorded on two faces during the traverse stage, along with the computed horizontal distances.

Instrument Station	Target Station	Face 1 Hor. Angle	Face 2 Hor. Angle	Line	Mean Distance
9	12 10	00°00′00″ 100°08′20″	179°59′58″ 280°08′14″	9-10	60.025m
10	9 11	00°00′00″ 50°56′54″	180°00′05″ 230°56′46″	10-11	21.134m
11	10 12	00°00′00″ 131°07′41″	179°59′56″ 311°07′40″	11-12	49.995m
12	11 9	00°00′00″ 77°46′38″	180°00′06″ 257°46′45″	12-9	18.512m

Table Q.2

The W.C.B. of the line 9-10 was determined accurately as 71°10′34″ with the coordinates of 9 being 1039.712m E, 1022.578m N.

• Determine the mean horizontal angle recorded at each instrument station. (7)

 

• Using Worksheet Q.2 complete and adjust the traverse.                               (8)

 

• Comment on the accuracy of the results.                               (2)

 

(Total 17)

Q3

Four corners V,X,Y and Z of a proposed Telephone mast base are to be set out initially from Station “A” by angle and distance and then checked by intersection from station “D”.

The stations and the detail points are all based on the same coordinate system and are given in the table below.

 

Station	Easting	Northing
A	1000.000	1000.000
D	984.396	994.269
Detail points
V	994.478	999.223
X	994.478	1000.723
Y	991.478	1000.723
Z	991.478	999.223

 

• Describe with full calculations a method of setting out the 4 points. (9)
• Describe a method of checking the position of the points again showing all working.

(7)

Total (16)