What Different Types Of Surveys Are There?

Lot Survey: This is a survey of a lot in a recorded subdivision. Corners should be marked in accordance with existing state standards, and the owner receives a drawing depicting what comers were set and what comers were found.

Boundary Survey: These surveys are normally described by Metes and Bounds and may require extensive research of adjoining deeds, original government surveys, highway plans, etc. A Boundary Survey usually requires field work on neighboring lands to verify or find existing monumentation. Because many deeds were prepared in an office and not actually surveyed, and others are just poorly written, it may require extra research and field work to determine the property lines. The comers should be marked in accordance with existing state standards, and the owner receives a drawing depicting what comers were set and what comers were found, and the relationship between deed lines and lines of possession.

Subdivision Survey: This type of survey divides existing parcels into smaller parcels. These types of surveys           are required to be recorded at the county recorder's office and must also meet all requirements of government agencies. State standards require a minimum of two permanent monuments per block.

Topographic Survey: Although these are generally performed by a Land Surveyor, other professionals, such as Engineers and Architects may also complete them. These types of surveys are graphic representations of physical features of the land depicting natural and man-made features, such as fences, buildings, utilities, hills, valleys streams, lakes, roads, etc. They can be performed by field ground methods or by aerial photographic methods. The preciseness of this type of survey depends on what it is to be used for. These surveys should be completed in conjunction with a ''Boundary Survey'' (which can only be performed by a Professional Land Surveyor) to show lines of possession.

Plot Plan or Site Plan:This type of survey may be required by local authorities or you may require it to insure that a proposed house or structure is constructed in the proper location and not over an easement or building set back line. A drawing may be required showing the proposed building location.

Surveyors Real Property Report: This is a report on the location of improvements and a cursory check for encroachments onto or from the subject property based on existing evide.

Surveying Short Question

Question 1.What Is Surveying?

Answer :

The profession or work of examining and recording the area and features of a piece of land so as to construct a map, plan, or detailed description of it.

Question 2. What Is A Surveyor?

Answer :

Surveyors update boundary lines and prepare sites for construction so that legal disputes are prevented. Surveyors make precise measurements to determine property boundaries. They provide data relevant to the shape and contour of the Earth's surface for engineering, map making, and construction projects.

Question 3. What Is A Property Surveyor?

Answer :

It is important, therefore, that you employ a surveyor yourself to undertake a thorough inspection of the property you wish to buy. The types of surveys available. There are two main types of structural survey available for those buying a property: a Home buyer's Report or a Full Building Survey.

Question 4. What Is A Marine Surveyor?

Answer :

A Marine surveyor (including "Yacht & Small Craft Surveyor", "Hull & Machinery Surveyor" and/or "Cargo Surveyor") is a person who conducts inspections, surveys or examinations of marine vessels to assess, monitor and report on their condition and the products on them, as well as inspects damage caused to both vessels .

Types of Leveling Instruments.

Types of Leveling Instruments

According to the general arrangement of various parts, the levels may be classified as:

1. Dumpy level,
2. Wye level,
3. Reversible level such as Cooke’s reversible level and Cushing’s level, and
4. Tilting level.

1.Dumpy level.

In the modern form of Dumpy level also called “solid Dumpy level”, the vertical spindle and the telescope are rigidly fixed so that the telescope can neither be rotated about its longitudinal axis nor removed from the supports.

This leveling instrument is more stable when compared to others and retains its permanent adjustment for a long time.

2. Wye or Y level.

In this instrument, the stage carries two “wye” supports in which the telescope is fixed.

To the body of the telescope, two hanged collars of equal diameters are fixed. These collars rest on the “Wyes.”

The telescope can be rotated about its longitudinal axis, or it can be taken out and placed end-for-end in the wyes.

A clamp and a tangent screw are provided to facilitate accurate sighting of the objects. This is a very delicate instrument and consists of a large number of loose and open parts.

Due to the reversibility of the telescope, the instrument may be more easily tested for permanent adjustments.

Comparing the Dumpy and the Wye levels, the Dumpy level is better suited for field work than the Wye level as the Wye level is not as compact as a Dumpy level. The Dumpy level is more reliable due to its solid and rigid construction.

The advantages of a Wye level are that the same may be tested for the permanent adjustment rapidly and the adjustment can be made indoors.

3. Cooke’s reversible level.

This Levelling instrument combines the good features of both the Dumpy and the Wye levels.

By loosening the screw, the telescope can be rotated about its longitudinal axis and can also be withdrawn from the sockets and placed end-for-end.

4. Cushing’s level.

Cushing’s level is in that type of levelling instruments in which, the telescope is rigidly fixed in the collar as in a Dumpy Level.

The two ends of the telescope barrel have equal sockets which can either received the objective or the eye-piece and diaphragm.

Reversal of the line of collimation may be established by interchanging the objective and the eyepiece. The eye-piece can be rotated in its fitting.

5. Tilting Level.

In the above four types of levelling instruments, the line of collimation is at the right angle to the vertical axis, if the instrument is in the permanent adjustment.

Therefore, when the bubble is centered the line of collimation is made horizontal and the vertical axis is made truly vertical.

In the tilting level, the telescope along with its bubble tube can be leveled by a micrometer screw without using the foot screws of the instrument, i.e., the line of collimation may be made horizontal independent of the vertical axis.

Originally, the tilting levels were designed for preliminary works only, but now they have become very popular and are being used for ordinary levelling also.

As the micrometer screw tilts the telescope in a vertical plane, the level is called a tilting level.

When a tilting level is used for levelling work, the vertical axis is only approximately set vertical by levelling screws.

(Unlike the other types of levelling instruments in which, the bubble should be exactly centered by foot screws).

…and before taking each Staff reading the main level tube is exactly centered by means of the micrometer screw.

The advantage of tilting level over other types of levelling instruments is that as the instrument is to be only approximately levelled by using the foot screws, much time is saved, which would be otherwise lost in bringing the bubble exactly to the center of its tube by using the foot screws.

Another advantage is that the grades or lines with a particular gradient can be laid by means of the micrometer screw.

Leveling Instruments used in Surveying.

Leveling Instruments used in Surveying.

• Leveling Instruments used in Surveying.
• Types of Leveling Instruments
• 1.Dumpy level.
• 2. Wye or Y level.
• 3. Cooke’s reversible level.
• 4. Cushing’s level.
• 5. Tilting Level.
• 
  
• Levelling instruments are employed for determining the relative heights of different points on the earth’s surface.
  A level essentially consists of a telescope to which a bubble tube is attached such that the axis of the bubble tube and the line of collimation of the telescope are parallel to each other.
  The instrument is provided with leveling screws by which the bubble tube is centered, and the line of collimation is brought into a horizontal plane.
• The levelling instrument irrespective of its type essentially consists of:
  1. Leveling head with foot screws
  2. Telescope and
  3.  level or bubble tube;
  The Leveling head usually consists of two parallel plates the upper plate is supported over the lower plate by three or four-foot screws or leveling screws by which the instrument may be leveled.
  Most of the modern Levelling instruments are designed to have three-foot screws because they are easily leveled.
  The telescopes used in surveying instruments consists of metal tubes, one moving axially within the other.
  There are mainly two types of telescope, (1) the external focusing telescope, and (2) the internal focusing telescope.

What is Leveling? | Important Terms in Surveying and Leveling.

What is Leveling in Surveying?

The art of determining the relative heights of points on the surface of the earth is termed as “leveling.”

A leveling instrument called “Level” and “Staff” is employed for this purpose along with other equipments which are explained in this article in details.

Definition of Important Terms in Surveying and Levelling.

Level Surface.

This is a surface which is normal to the direction of gravity at all points as indicated by a plumb line. The surface of a still lake may be taken as an example of a level surface.

As the earth is an oblique spheroid, a level surface will not be plane but will be a cursed one. Every point on a level surface is equidistant from the center of the earth.

Level Line.

A line lying throughout on a level surface is a level line. This is normal to the plumb line at all points.

Horizontal Plane.

A horizontal plane through a point is a plane tangential to the level surface at the point. This is normal to the direction of gravity at that point.

Horizontal Line.

Any line lying throughout in a horizontal plane is termed as “horizontal line.”

Vertical Plane.

A vertical plane is any plane containing a vertical line. A vertical line at any point is a line normal to the level surface at that point. A plumb line is an example of a vertical line.

Read Also: Surveying Tapes: Types of Measuring Tape Used in Survey.

Datum Surface.

This is an arbitrary surface with reference to which the elevations of points are measured and compared.

Elevation of a Point.

Elevation of a point is the vertical distance above or below the datum. This is usually called the reduced level (R.L) of the point. This may be positive or negative accordingly as the point is above or below the datum.

Line of Collimation.

The line of collimation or the line of sight is the line joining the intersection of cross-hairs to the optical center of the object glass and its continuation.

Axis of Telescope.

The axis of a telescope is the line joining the optical center of the object glass to the center of the eye piece.

Axis of Bubble Tube.

The axis of bubble tube or level tube is the line tangential to the longitudinal curve of bubble tube at its middle point. This is horizontal when the bubble is centered. This is also called “bubble line.”

Vertical Axis.

The vertical axis is the line about which the telescope can be rotated in a horizontal plane.

Civil Engineering tool for Surveying Chain tape:

Civil Engineering tool for Surveying Chain tape:

The chain tape is also referred to as the Günter’s chain. Gunter’s chain, the 300 –year-old measuring instrument by which all survey measurement in the English – speaking countries and much of it elsewhere was done. It has been superseded by the steel tape and electronic equipment. Gunter’s chain is 66 feet long; 80 chain equal to one mile, and 10 square chains equals an acre. The chain is subdivided into 100 links. A rod or perch was 25 links. Each link was a short section of wire connected to the next by a loop. At each end of the chain was a brass handle. The 66 – foot unit is still called a chain and is still in use in property descriptions and in the public land system. The Gunter chain is generally used in taking short and detailed length and breadth of a school farmstead.

DRY DENSITY OF SOIL BY CORE CUTTER METHOD

TO DETERMINE DRY DENSITY OF SOIL BY CORE CUTTER METHOD

Theory:

A cylindrical core cutter is a seamless steel tube. For determination of the dry density of the soil, the cutter is pressed into the soil mass so that it is filled with the soil. The cutter filled with the soil is lifted up. The mass of the soil in the cutter is determined. The dry density is obtained as

Where M= mass of the wet soil in the cutter

V= internal volume of the cutter

w= water content.

Equipment:

1. Cylindrical core cutter, 100mm internal diameter and 130mm long

2. Steel rammer, mass 9kg, overall length with the foot and staff about 900mm.

3. Steel dolley, 25mm high and 100mm internal diameter

4. Weighing balance, accuracy 1g.

5. Palette knife

6. Straight edge, steel rule etc

Procedure

1. Determine the internal diameter and height of the core cutter to the nearest 0.25mm

2. Determine the mass (M1) of the cutter to the nearest gram.

3. Expose a small area of the soil to be tested. Level the surface, about 300mm square in area.

4. Place the dolley over the top of the core cutter and press the core cutter into the soil mass using the rammer. Stop the pressing when about 15mm of the dolley protrudes above the soil surface.

5. Remove the soil surrounding the core cutter, and take out the core cutter. Soil soil would project from the lower end of the cutter.

6. Remove the dolley. Trim the tip and bottom surface of the core cutter carefully using a straight edge.

7. Weigh the core cutter filled with the soil to the nearest gram (M2).

8. Remove the core of the soil from the cutter. Take a representative sample for the water content determination.

9. Determine the water content.

Observation and calculations:

Sl. No.	Observations an Calculations	Determination No.
		1	2	3
Observation
1	Core cutter No.
2	Internal diameter
3	Internal height
4	Mass of empty core cutter (M1)
5	Mass of core cutter with soils (M2)
Calculations
6	M=M2 – M1
7	Volume of cutter V
8	Water content
9	Dry density using formula

Result:

Dry density of the soil= ________g/ml.

Measurement of distance with tapes

Precisions for different methods of measuring distances are given below:-

Pacing (ordinary terrain): 1/50 to 1/100

Taping (ordinary steel tape): 1/1000 to 1/10,000.

Baseline (invar tape): 1/50,000 to 1/1,000,000

Stadia: 1/300 to 1/500

Subtense bar: 1/1000 to 1/7000

Now with technological advances, a technique called Electronic distance measurement or EDM is replacing the use of steel tapes as they are much more precise then steel tapes.

Ranging and Fixing Of Survey Station

The object of this experiment is to set up a survey station. This is the basic step of surveying but this is also the one which has the maximum number of errors.

The Equipments used for this are :-

1. Ranging rod …………5 Nos. (min).
2. 30 m Chain…………..1 Nos.
3. Arrow…………………5 Nos. (min.)

The Procedure to conduct is as follow :

(Ranging by eye)
1. First of all first ranging rod is established at known point A and its ranging rod should be fixed at point A up to completion of work.

2. Second ranging rod is established at known point B (or at known object) and a ranging rod should be fixed at point B up to completion of work.

3. Third ranging rod established at point P (or any) approximately on the line of point AB (by judgment) and it’s not greater than one chain length from point A.

4. Measure the distance of AP by chain and move ranging rod at point P to its next position and establishing a wooden peg or arrow at point P.

5. Third ranging is established at point Q (or any) approximately on the line of point AB (by judgment) and it’s not greater than one chain length from point P.

6. Measure the distance of PQ by chain and move ranging rod at point Q to its next position and establishing a wooden peg or arrow at point Q.

7. Its procedure repeats up to reaching point B.

8. Third ranging rod is established at known point C (or at known object) and a ranging rod should be fixed at point C up to completion of work.

9. Fourth ranging rod established at point P’ (or any) approximately on the line of point BC (by judgment) and it’s not greater than one chain length from point B.

10. Measure the distance of BP’ by chain and move ranging rod at point P’ to its next position and establishing a wooden peg or arrow at point P’.

11. Fourth ranging is established at point Q’ (or any) approximately on the line of point BC (by judgment) and it’s not greater than one chain length from point P’.

12. Measure the distance of P’Q’ by chain and move ranging rod at point Q’ to its next position and establishing a wooden peg or arrow at point Q’.

13. Its procedure repeats up to reaching point C.

14. Fifth ranging rod established at point P” (or any) approximately on the line of point CA (by judgment) and it’s not greater than one chain length from point C.

15. Measure the distance of CP” by chain and move ranging rod at point P” to its next position and establishing a wooden peg or arrow at point P”.

16. Fifth ranging is established at point Q” (or any) approximately on the line of point CA (by judgment) and it’s not greater than one chain length from point P”.

17. Measure the distance of P”Q” by chain and move ranging rod at point Q” to its next position and establishing a wooden peg or arrow at point Q”.

18. Its procedure repeats up to reaching point A.

19. Finally complete a triangle and position of point A, B, and C is known respect to each other.

Precautions: – 
1. The ranging rod should be established correctly state at all points.
2. The judgment of line should be taking correctly during established ranging rod at a point.
3. Distance between surveyor’s eye and reference station (eg. A, B and C) should be minimum one meter.

What is Orthometric Correction?

We know that earth flattens in the polar direction and this curvature of earth is responsible for the departure of horizontal line from a level surface. To counter this error, orthometric corrections is applied.

This departure in feet, C_f is calculated as
C_f= 0.667M²=0.0239F²

This departure in meters, C_m is calculated
C_m =0.0785K ²

where M = distances in miles from the point of tangency to the earth.
F= distances in thousands of feet from the point of tangency to the earth.
K = distances in kilometers from the point of tangency to the earth.

What are the Corrections Applied in Surveying?

For surveying, we need to have some prerequisite conditions. If these conditions are not met we can have a huge variation in result. Therefore we have to apply corrections to get the true result.

Ideal Conditions
1) A tape accurate to 0.00305m or 0.01 ft should be used.
2) Tension of the tape should be about 66.7N or 15 lb.
3) Temperature should be determined within 5.56°C or 10°F
4) The slope of the ground, should be within 2 percent

On ground these are nearly impossible to achieve and thus corrections need to be applied.

Corrections Applied for Temperature
The correction applied on steel tape is C_t=0.0000065s(T-T₀)
where
C_t= temperature correction to measured length, ft (m)
T=temperature at which measurements are made, F ( C)
T₀= temperature at which tape is standardized, F ( C)
s= measured length, ft (m)

Correction Applied to Measurements on Slope
C_h= s (1-cos@) [exact]
or = 0.00015s@²[approximate]
or = h²/2s
where
C_h= correction to be subtracted from slope distance, ft (m)
s= measured length, ft (m)
@ =slope angle, degree
h= difference in elevation at ends of measured length, ft (m)

Correction Applied for Tension 
C_p=s[P_m-P_s]/SE

Correction Applied for Sag when not Fully Supported
C_s=w²L³/24P_m²

where
C_p= tension correction to measured length, ft (m)
C_s = sag correction to measured length for each section of unsupported tape, ft (m)
P_m actual tension, lb (N)
P_s tension at which tape is standardized, lb (N) (usually 10 lb) (44.4 N)
S=cross-sectional area of tape, in² (mm²)
E= modulus of elasticity of tape, lb/in² (MPa) (29 million lb/in²(MPa) for steel) (199,955 MPa)
w= weight of tape, lb/ft (kg/m)
L= unsupported length, ft (m)

What are Slope Corrections?
We know that the horizontal distance H= Lcos@, where L slope distance and @=vertical angle, measured from the horizontal.

For slopes of 10 percent or less
C_s=d²/2L

For a slope greater than 10 percent
C_s=d²/2L+d⁴/8Ld³

What are Temperature Corrections in terms of length?
C_t=(actual tape length-nominal tape length)L/nominal tape length

For nonstandard tension:
C_t(applied pull-standard tension)L/AE
where A= cross-sectional area of tape, in² (mm²)
E=modulus of elasticity29,000,00 lb / in² for steel (199,955 MPa).

For sag correction between points of support, ft (m):
C= -w²L³_s/24P²
where
w = weight of tape per foot, lb (N)
L_s= unsupported length of tape, ft (m)
P=pull on tape, lb (N)