Preliminary Eng

jeddah · · processed · 122 chunks

[Non-Text]
Kingdom Of Saudi Arabia
Ministry of municipal & Rural Affairs
Deputy Ministry for Technical Affairs
MOMRA
Bridges, Tunnels, Culverts and Pedestrian
Bridges Specifications in Urban Areas
Preliminary studies
MA 100-P-V1/1
2013

[Non-Text]
Kingdom Of Saudi Arabia
Ministry of municipal & Rural Affairs
Deputy Ministry for Technical Affairs
Introduction
As for the importance and vitality of road constructions and the need to control them so as to perform their function in an appropriate way throughout their service age.
So many countries and Organizations had prepared specifications for design and construction these structures.
These Specifications were differed from one another according to the environment and the nature of the climate.
For instance some organizations and societies in U.S.A.
Such as the American Association of State Highway and Transportation Officials (AASHTO).
These organizations and societies have improved and updated design specification.
In the same way each state in U.S.A.
has developed its own specification mainly based on AASHTO specification and refers to them In different situations, but they will be suitable for the circumstances of the State that has improved them.
As for K.S.A.
which is one of the countries that has a large transportation network and many road structures, so the necessity arose to prepare suitable specification for these structures to suit the environmental circumstances and the transportation policy that has adopted in K.S.A.
So the Kingdom of Saudi Arabia representative in the Ministry of Municipal and Rural Affairs has taken the role of collecting the specification under the title Bridges, Tunnels, culverts, pedestrian bridges in the urban areas.
These specifications include the following:
1- Preliminary studies
2- Design specifications
3- Construction specifications
The ministry has also updated codes for both bridges and culverts manuals according to the new specifications.
[Non-Text]
Kingdom Of Saudi Arabia
Ministry of municipal & Rural Affairs
Deputy Ministry for Technical Affairs
Specifications Books
<table><tr><td>1</td><td>Preliminary studies</td><td>MA 100-P-V1/1</td></tr><tr><td>2</td><td>Construction specifications</td><td>MA 100-C-V1/1</td></tr><tr><td>3</td><td>Design specifications</td><td>MA 100- D- V1/2</td></tr><tr><td>4</td><td>Design specifications</td><td>MA 100-D- V2/2</td></tr></table>

TABLE OF CONTENTS
TABLE OF CONTENTS
TABLE OF CONTENTS......I
SECTION 1.
SURVEY WORKS ....
1
1.1.
IMPORTANCE AND TYPES OF SURVEYS ....
1
1.1.1.
Importance Surveys ....
1
1.1.2.
Types of Surveys....2
1.1.2.1.
Control Survey....2
1.1.2.2.
Boundary Survey ....
2
1.1.2.3.
Topographic Survey....3
1.1.2.4.
Hydrographic Survey....3
1.1.2.5.
Mining Survey ....
3
1.1.2.6.
Construction Survey....3
1.1.2.7.
Route Survey....3
1.1.2.8.
Photogrammetric Survey ....3
1.2.
EQUIPMENT CHECKING AND CALIBRATION....3
1.2.1.
General....3
1.2.2.
Equipment....3
1.2.3.
Electronic Survey Instruments Adjustments, Calibration or Repairs ....3
1.2.4.
Equipment Types ....4
1.2.5.
Survey Crew Responsibilities ....4
1.2.6.
Equipment Care and Protection ....5
1.2.7.
Routine Instrument Maintenance....5
1.2.8.
Equipment Maintenance ....6
1.2.9.
Calibrations ....7
1.2.9.1.
General....7
1.2.9.2.
Calibration Baseline Check....7
1.3.
PRELIMINARY SURVEY ....8
1.3.1.
Presurvey Conference/Preliminary Survey ....8
1.3.2.
Reconnaissance Survey....9
1.3.2.1.
Reconnaissance on Vertical Aerial Photographs ....10
1.3.2.2.
Reconnaissance on Existing Maps....10
1.3.2.3.
Reconnaissance on New Maps....10
1.3.2.4.
Comparison of Alternatives ....
10
1.3.3.
Research....11
1.3.3.1.
General....11
1.3.3.2.
Types of Research....11
1.3.3.3.
Office Research....11
1.3.3.4.
Field Search 12
1.3.4.
Drainage Survey....13
1.3.4.1.
General....13
1.3.4.2.
Aerial Photogrammetry Methods....13
1.3.4.3.
Photographs 14
1.3.4.4.
Guidelines 14
1.3.5.
Utility Survey....16
3 October 2013
i

TABLE OF CONTENTS
1.4.
CONSTRUCTION SURVEY....
16
1.4.1.
Location Survey 16
1.4.2.
Centerline Survey 16
1.4.3.
Profile....
17
1.4.4.
Slope Stakes 17
1.4.5.
Structure Stakes....
18
1.4.6.
Grade Stakes....
18
1.4.7.
Earthwork Quantities....
18
1.5.
GLOBAL POSITIONING SYSTEMS (GPS)....
18
1.6.
SAFETY FOR LOCATION SURVEYORS 18
1.6.1.
INTRODUCTION....
18
1.6.2.
WEARING OF PERSONAL PROTECTIVE EQUIPMENT 19
1.6.3.
USE OF TRAFFIC CONTROL DEVICES 20
1.6.3.1.
WARNING SIGNS 20
1.6.3.2.
Channelizing Devices....
21
1.6.3.3.
Advance Warning Arrow Panel 21
1.6.3.4.
Variable Message Signs (VMS) 21
1.6.3.5.
Flagging Operations 21
1.6.3.6.
Inspections....
22
1.6.3.7.
Vehicle Warning Lights 22
1.6.4.
Safety Rules While Working in Traffic....
22
1.7.
TOPOGRAPHIC SURVEY REQUIREMENTS AND REPORTING: 23
1.7.1.
Coordinates According to the Surface of the Geodetic Reference for GPS 23
1.7.2.
Topographic Survey Study Submittals: 24
1.8.
REFERENCES 24
SECTION 2.
HIGHWAY HYDROLOGY 25
2.1.
INTRODUCTION....
25
2.2.
DEFINITIONS....
25
2.3.
HYDROLOGIC CYCLE....
27
2.4.
HYDROLOGY OF HIGHWAY STREAM CROSSINGS 28
2.4.1.
Elements of the Hydrologic Cycle Pertinent to Stream Crossings 28
2.4.2.
Overview of Hydrology as Applied to Stream Crossings 29
2.4.3.
Diversions and Dam Construction 30
2.4.4.
Natural Disasters 30
2.5.
RAINFALL/RUNOFF PROCESSES 31
2.5.1.
Precipitation 31
2.5.1.1.
Forms of Precipitation....
31
2.5.1.2.
Types of Precipitation (by Origin) 31
2.5.1.3.
Characteristics of Rainfall Events 31
2.5.2.
Hydrologic Abstractions....
32
2.5.2.1.
Evaporation 32
2.5.2.2.
Transpiration 33
2.5.2.3.
Interception 33
2.5.2.4.
Infiltration 33
2.5.2.5.
Depression Storage....
33
2.5.2.6.
Detention Storage....
33
ii
3 October 2013

TABLE OF CONTENTS
2.5.3.
Characteristics of Runoff 33
2.5.3.1.
Peak Discharge 34
2.5.3.2.
Time Variation (Hydrograph) 34
2.5.3.3.
Stage -Discharge 34
2.5.3.4.
Total Volume 35
2.5.3.5.
Frequency....35
2.5.3.6.
Return Period 36
2.5.4.
Effects of Basin Characteristics on Runoff....36
2.5.4.1.
Drainage Area 36
2.5.4.2.
Slope 36
2.5.4.3.
Hydraulic Roughness 37
2.5.4.4.
Storage 37
2.5.4.5.
Drainage Density 39
2.5.4.6.
Channel Length....39
2.5.4.7.
Antecedent Moisture Conditions 40
2.5.4.8.
Urbanization....40
2.5.4.9.
Other Factors....40
2.6.
HYDROLOGIC DATA 40
2.6.1.
Topographic Maps 40
2.6.2.
Photographs....41
2.6.3.
Land Use 41
2.6.4.
Water Use....41
2.6.5.
Rainfall Data 41
2.6.6.
Gaging Station Data....41
2.6.7.
Highwater Marks 42
2.7.
HYDROLOGIC ANALYSIS 42
2.7.1.
Drainage Area 42
2.7.2.
Watershed Parameters....42
2.7.2.1.
Basin Length 42
2.7.2.2.
Basin Slope 42
2.7.2.3.
Percent Impervious 43
2.7.2.4.
Infiltration 43
2.7.2.5.
Detention Depression Storage....43
2.7.2.6.
Drainage Basin Roughness Coefficients....43
2.7.2.7.
Channel or Conduit Slope....44
2.7.2.8.
Channel or Conduit Cross Section....45
2.7.2.9.
Channel or Conduit Roughness 45
2.7.3.
Flood Estimates....49
2.7.3.1.
Rational Equation....50
2.7.3.2.
Gumbel Distribution ....57
2.7.3.3.
Indirect Estimates....60
2.7.3.4.
Regression Equations....61
2.8.
HIGHWAY CULVERTS DESIGN....63
2.8.1.
Introduction....63
2.8.2.
Design Considerations ....64
2.8.2.1.
Design Discharge....64
2.8.2.2.
Headwater 64
2.8.2.3.
Tailwater....65
2.8.2.4.
Outlet Velocity....65
2.8.3.
Culvert Flow 65
2.8.3.1.
Inlet Control....65
2.8.3.2.
Outlet Control 66
2.8.4.
Performance Curves....67
3 October 2013
iii

TABLE OF CONTENTS
2.8.5.
Procedure for Selection of Culvert Size 68
2.8.5.1.
Step1- List Design Data 68
2.8.5.2.
Step 2-Determine the first trial size culvert....68
2.8.5.3.
Step 3-Find headwater depth for trial size culvert.
69
2.8.5.4.
Step 4- Try a culvert of another type or shape and determine size and HW by the above procedure....70
2.8.5.5.
Step 5-Compute outlet velocities for size and types to be considered in selection and determine need for channel protection ....
70
2.8.5.6.
Step 6-Record final selection of culvert, the size, type required headwater, outlet velocity, and economic justification....70
2.8.6.
Protection 75
2.8.6.1.
Debris Control....75
2.8.6.2.
Buoyancy....75
2.8.7.
Sedimentation....76
2.9.
REFERENCES....76
SECTION 3.
GEOTECHNICAL STUDIES ......
77
3.1.
PROJECT GEOTECHNICAL PLANNING....77
3.1.1.
General 77
3.1.1.1.
Introduction....77
3.1.1.2.
Objective 77
3.1.1.3.
Reports 77
3.1.2.
Geotechnical Project Elements....78
3.1.3.
Geotechnical Input for Reconnaissance Phase 78
3.1.3.1.
Objective 78
3.1.3.2.
Tasks 78
3.1.3.3.
Report 79
3.1.4.
Geotechnical Input for Preliminary Design Phase 80
3.1.4.1.
Objective 80
3.1.4.2.
Tasks 80
3.1.4.3.
Report 82
3.1.5.
Geotechnical Input for Final Design Phase 83
3.1.5.1.
Objective 83
3.1.5.2.
Tasks 83
3.1.5.3.
Report 85
3.2.
FIELD INVESTIGATION 87
3.2.1.
Exploration Spacing and Layout 87
3.2.1.1.
Structure-Specific Borings 87
3.3.
ENGINEERING PROPERTIES OF SOIL AND ROCK 88
3.3.1.
Engineering Properties of Soils 88
3.3.1.1.
Permeability 88
3.3.1.2.
Elasticity 88
3.3.1.3.
Plasticity 89
3.3.1.4.
Cohesion....89
3.3.1.5.
Angle of Internal Friction ( \( \Phi \) ) 89
3.3.1.6.
Moisture Content....89
3.3.1.7.
Density 89
3.3.1.8.
Shrink/Swell Potential....89
3.3.1.9.
Compressibility 89
iv
3 October 2013

TABLE OF CONTENTS
3.3.1.10.
Grain Size Distribution ....90
3.3.2.
Grain Size Distribution Chart ....90
3.3.3.
Engineering Properties of Rocks....91
3.3.3.1.
Density 91
3.3.3.2.
Strength and Hardness 91
3.3.3.3.
Durability 91
3.3.3.4.
Joints and Faults....91
3.4.
SLOPE STABILITY ANALYSIS....92
3.4.1.
Overview....92
3.4.1.1.
Introduction....92
3.4.2.
Analysis and Design 97
3.4.2.1.
Overview....97
3.4.3.
Slope Repair....99
3.4.3.1.
Overview....99
3.5.
REFERENCES....100
3 October 2013
v

TABLE OF CONTENTS
vi
3 October 2013

Importance and Types of Surveys
Section 1: Survey Works
SECTION 1.
SURVEY WORKS
1.1.
IMPORTANCE AND TYPES OF SURVEYS
1.1.1.
Importance Surveys
Surveying is the science and art of determining relative positions of features on or near the surface of the earth.
Surveying is a prerequisite to civil engineering design and Right of Way acquisition.
In transportation engineering, surveying provides the foundation and continuity for route control, location, photogrammetry, design, Right of Way mapping, land acquisition, access issues, Geographical Information Systems (GIS), and all other preliminary engineering including traffic, hydraulics and bridges.
Surveys also set a basic "framework" of stakes in which are used by contractors and state engineers in building and inspecting highway projects.
Surveying is the single function that ties all the elements of a project, from conception through design, Right of Way mapping, land acquisition, and construction to final Right of Way monumentation and Geographical Information Systems data.
To a large degree, the acceptability and cost effectiveness of planning, Right of Way mapping, land acquisition, design and construction is dependent upon properly performed surveys.
Surveying is one of the oldest activities of the civil engineer, and remains a primary component of civil engineering.
It is also one field that continues to undergo phenomenal changes due to technological developments in digital imaging and satellite positioning.
These modern surveying tools are not only revolutionizing regular surveying engineering tasks but are also impacting a myriad of applications in a variety of fields where near-real-time positioning is of great value.
Surveying and engineering are closely related professional activities.
The area of surveying and mapping is in many countries a discipline by itself, and taken in total, it is almost as broad in scope as civil engineering.
Engineering surveying is also defined as those activities involved in the planning and execution of surveys for the location, design, construction, operation, and maintenance of civil and other engineered projects.
Such activities include the preparation of survey and related mapping specifications; execution of photogrammetric and field surveys for the collection of required data, including topographic and hydrographic data; calculation, reduction, and plotting of survey data for use in engineering design; design and provision of horizontal and vertical control survey networks; provision of line and grade and other layout work for construction and mining activities; execution and certification of quality control measurements during construction; monitoring of ground and structural stability, including alignment observations, settlement levels, and related reports and certifications; measurement of material and other quantities for inventory, economic assessment, and cost accounting purposes; execution of as-built surveys and preparation of related maps and plans and profiles upon completion of construction; and analysis of errors and tolerances associated with the measurement, field layout, and mapping or other plots of survey measurements required in support of engineering projects.
Engineering surveying may be regarded as a specialty within the broader professional practice of engineering and, with the exception of boundary, right-of-way, or other cadastral surveying, includes all surveying and mapping activities required to support the sound conception, planning,
3 October 2013
1

Section 1: Survey Works
Importance and Types of Surveys
design, construction, maintenance, and operation of engineered projects.
Engineering surveying does not include surveys for the retracement of existing land ownership boundaries or the creation of new boundaries.
Modern surveying engineering encompasses several specialty areas, each of which requires substantial knowledge and training in order to attain proper expertise.
The most primary area perhaps is planem surveying because it is so widely applied in engineering and surveying practice.
In plane surveying, we consider the fundamentals of measuring distance, angle, direction, and elevation.
These measured quantities are then used to determine position, slope, area, and volume — the basic parameters of civil engineering design and construction.
Plane surveying is applied in civil engineering projects of limited areal extent, where the effects of the earth’s curvature are negligible relative to the positional accuracy required for the project.
Geodesy, or higher surveying, is an extensive discipline dealing with mathematical and physical aspects of modeling the size and shape of the earth, and its gravity field.
Since the launch of earth-orbiting satellites, geodesy has become a truly three-dimensional science.
Terrestrial and space geodetic measurement techniques, and particularly the relatively new technique of satellite surveying using the Global Positioning System (GPS), are applied in geodetic surveying.
GPS surveying has not only revolutionized the art of navigation but has also brought about an efficient positioning technique for a variety of users, prominent among them the engineering community.
GPS has had a profound impact on the fundamental problems of determining relative and absolute positions on the earth, including improvements in speed timeliness, and accuracy.
It is safe to say that any geometry-based data collection scheme profits to some degree from the full constellation of 24 GPS satellites.
In addition to the obvious applications in geodesy, surveying, and photogrammetry, the use of GPS is applied in civil engineering areas such as transportation (truck and emergency vehicle monitoring, intelligent vehicle and highway systems, etc.) and structures (monitoring of deformation of structures such as water dams).
Even in other areas such as forestry and agriculture (crop yield management) GPS provides the geometric backbone of modern (geographic) information systems.
Survey data is portrayed graphically by the construction of maps, profiles, cross sections, and diagrams.
1.1.2.
Types of Surveys
The type of surveying that takes into account the true shape of the earth.
These surveys are of high precision and extend over large areas.
The type of surveying in which the mean surface of the earth is considered as a plane, or in which its spheroidal shape is neglected, with regard to horizontal distances and directions.
1.1.2.1.
Control Survey
Made to establish the horizontal and vertical positions of arbitrary points.
1.1.2.2.
Boundary Survey
Made to determine the length and direction of land lines and to establish the position of these lines on the ground.
2
3 October 2013

Equipment Checking and Calibration
Section 1: Survey Works
1.1.2.3.
Topographic Survey
Made to gather data to produce a topographic map showing the configuration of the terrain and the location of natural and man-made objects.
1.1.2.4.
Hydrographic Survey
The survey of bodies of water made for the purpose of navigation, water supply, or subaqueous construction.
1.1.2.5.
Mining Survey
Made to control, locate and map underground and surface works related to mining operations.
1.1.2.6.
Construction Survey
Made to layout, locate and monitor public and private engineering works
1.1.2.7.
Route Survey
Refers to those controls, topographic and construction surveys necessary for the location and construction of highways, railroads, canals, transmission lines, and pipelines.
1.1.2.8.
Photogrammetric Survey
Made to utilize the principles of aerial photogrammetry.
in which measurements made on photographs are used to determine the positions of photographed objects.
1.2.
EQUIPMENT CHECKING AND CALIBRATION
1.2.1.
General
Equipment must be properly maintained, regularly checked, and calibrated for accuracy at the beginning of any survey project to ensure that the equipment is operating properly.
Errors due to poorly maintained or malfunctioning equipment will not be accepted.
If any equipment errors are found to exist they must be reported to the Region Survey Coordinator prior to the start of the survey.
These errors will need to be verified and eliminated prior to performing any survey.
For surveys lasting longer than six months, the checking, and calibration of equipment shall be repeated once every six months to show that the equipment is staying within acceptable tolerances.
Any variation from the specifications shall have the prior approval of the Region Survey Coordinator.
1.2.2.
Equipment
Equipment is defined as any and all types of survey and or office survey equipment used to perform the functions of land surveying.
The specifications and procedures as stated in this chapter shall apply to any and all makes and models of equipment.
The specific maintenance, adjustment, care, use and, repair information is contained in the owners/operating manual for your instrument.
1.2.3.
Electronic Survey Instruments Adjustments, Calibration or Repairs
All electronic survey instruments shall be repaired, adjusted, or calibrated only by an authorized equipment vendor or manufacturers service department.
3 October 2013
3

Section 1: Survey Works
Equipment Checking and Calibration
1.2.4.
Equipment Types
There are many types of equipment used to perform the functions of land surveying.
The types of equipment include but are not limited to the following:
- Global Positioning System receivers, antennas, cables, poles, height rods, etc
• Electronic total stations with on-board data collectors
- Hand-held data collectors
• Electronic theodolites
• Electronic digital bar-code levels (First and Second Order)
- Automatic levels
• Electronic distance meters
- Bar code level and automatic level rods
- Hand-held calculators
- Lap-top computers
- Cellular telephones
- Battery chargers
- Cables / accessories
- Tribrachs
- Prisms
- Steel and fiberglass tapes
- Adjustable and fixed height tri-pods
- Chaining pins, poles, plumb-bobs, right angle prisms
- Prism poles
- Magnetic locators
- Power tools such as saws, grinders, jackhammers, etc.
- Hand tools such as sledge hammers, shovels, drivers etc.
- Hand-held two way radios
- Cameras
- Barometers / thermometers
- Traffic control devices
- First aid kits
- Vehicles
1.2.5.
Survey Crew Responsibilities
The survey crew chief is responsible for the crew's equipment and shall assure that all members are trained to properly care for the equipment and shall delegate the responsibilities accordingly.
The crew chief shall also see that the equipment is used for
4
3 October 2013

Equipment Checking and Calibration
Section 1: Survey Works
its intended purpose.
Members of a crew must understand the absolute necessity of using the proper equipment, in the proper condition, for the given tasks.
Proper care and respect for all equipment is required of every survey crew member.
1.2.6.
Equipment Care and Protection
For the care and protection of equipment the following rules shall be observed:
1.
Care shall be taken when moving survey instruments.
Manufacturer's recommendations shall be followed.
2.
Instruments such as total stations or theodolites should never be lifted by the standard or horizontal axis, rather by their base or handle.
3.
When equipment is being moved to or from its case or tripod, it should be lifted by the base or handle
4.
Never point an instruments telescope directly at the sun as the sun's rays will damage the diodes in the EDM, and may also result in permanent eye damage of the user.
5.
Never carry an instrument on its tripod over your should except as indicate by the instruments owners/operating manual.
6.
When equipment is being set up, the leveling screws should never be tightened any more than necessary to eliminate looseness.
Over tightening damages, the fine threads of the leveling screws, and sets up stresses that makes observations erratic and often will deform vital parts of the instrument.
7.
Instruments shall be protected from rapid change in temperature.
Instruments shall be allowed to acclimatize prior to use in accordance with the manufacturers requirements.
8.
All equipment is designed to withstand use in a wide range of weather conditions, but will not withstand forces that stress the parts beyond their elastic limit.
Care needs to be taken to not overstress equipment beyond the intended use.
9.
Electronic equipment should not be subjected to extended periods in wet weather due to possible damage to the electronics.
10.
Equipment left set up during rain showers will be covered with a waterproof covering.
Equipment that becomes wet shall be allowed to dry prior to storing in its case.
11.
Equipment should never be left unattended in areas where it might be knocked over or disturbed by pedestrians, animals, motor vehicles, wind, falling rocks, tree limbs or other causes.
12.
Whenever possible, select instrument setup locations to minimize the exposure of the instrument operator, other members of the crew, and the instrument to danger.
Select stable ground for the tripod feet.
13.
All instruments shall be stored in a safe, secure area when not in use.
1.2.7.
Routine Instrument Maintenance
Before using any survey instrument, visually inspect it for damage.
Check all machined surfaces including the polished faces of lenses and mirrors.
Snug up all clamps and check tangent motions for smooth operation.
These should move freely with the absence of binding or gritty sounds.
Clean the instrument exterior frequently.
Accumulation of dirt and dust can scratch or mar machined polished surfaces and cause friction and sticking in the motions.
Remove dust with a camel's-hair brush and clean soiled non-optical parts with a soft
3 October 2013
5

Section 1: Survey Works
Equipment Checking and Calibration
cloth or with a clean chamois.
Clean the external surfaces of lenses with a fine lens brush.
If necessary, use lens tissue.
Do not use silicone treated tissue that can damage coated optics.
Do not use any liquids other than pure alcohol.
Take care not to scratch lenses or their coating.
Never touch optical glass with your fingers.
Always use a lens cover when storing in the instrument case.
Do not loosen or attempt to clean the internal surface of any lens.
If any instrument or equipment has become wet, unpack it at the end of the day and after wiping it dry with a soft towel or cloth, leave the instrument and any of its accessories outside of the case to dry.
Also leave the case open to dry.
If the foam inserts for the case are wet, also remove them for drying.
Do not replace the instrument in the case until completely dry.
1.2.8.
Equipment Maintenance
At the beginning of any survey all survey equipment needed to perform the survey shall be checked and adjusted by the professional land surveyor in responsible charge of the survey under his/her direct supervision and/or checking.
All survey equipment shall be checked once every six months thereafter and as needed during the course of the survey, whichever comes first.
Checks shall include but are not limited to the following:
1.
GPS equipment – No cracks or visible signs of damage to the receivers or any cabling.
2.
Electronic Total Stations and Distant Meters/ Theodolites – No cracks or visible signs of damage.
Leveling screws and tangent screws are in adjustment and operate smoothly.
Level bubbles are in adjustment and operational.
Optical sights are clear, clean, not cracked or chipped.
Optical plummet is in adjustment.
Bottom of base mount is smooth and not damaged.
Horizontal and vertical columnations shall be checked daily adjusted as needed.
3.
Electronic / Automatic Levels – No cracks or visible signs of damage.
Leveling screws and tangent screws are in adjustment and operate smoothly.
Level bubbles are in adjustment and operational.
Optical sights are clear; clean, not cracked or chipped.
Two Peg test or other test as recommended in the manufacturers owners/operating manual should be performed and adjustments made as needed.
4.
Level Rods - Maintain level rods as you do other precise equipment.
Accurate leveling is as dependent on the condition of rods as on the condition of levels.
5.
Prism Poles - Level bubbles are checked and are in adjustment, rod is not bent or damaged, height of rod is correct as reportedly measured, and adjustable rod height clamps are secure.
6.
Tribrachs - Optical plummet is in adjustment, level bubble is in adjustment, no lose legs, no loose or missing screws, bottom head is flat and not damaged.
7.
Adjustable Leg Tripods - Nuts and bolts are tight, no loose or broken legs, tripod head is tight, flat, and not damaged.
A tripod is the base on which your instrument sits and should be kept in good condition so that the instrument can be depended on for the accuracy that it was built to obtain.
When the tripod is not in use, the tripod head cap should be used to protect the tripod head.
8.
Fixed Height Tripods - Level bubbles are in adjustment, rod is not bent or damaged, height of rod is correct as reportedly measured, legs are secure.
9.
Collimators - Level bubble is in adjustment, top and bottom heads are both flat with no damage.
10.
Cables - No cuts, breaks, pinch marks or damage.
6
3 October 2013

Equipment Checking and Calibration
Section 1: Survey Works
11.
Steel Tapes (Chains) - A steel tape is a precision tool manufactured under rigid specifications and should be treated as such.
The steel tape should never be pulled around a post, stake, or wound on a reel so tightly that the tape will stretch beyond the elastic limit.
Vehicles should not be allowed to run over steel tapes.
The kinks and bends that result will make the tapes inaccurate.
Wet or muddy steel tapes should be wiped dry and clean, oiled lightly, and dried again.
12.
Hand Levels - The hand level should be kept in adjustment per manufactures guidelines.
13.
Power and hand tools such as hammers, shovels, picks, axes, brush hooks, hatchets, etc., should be kept sharp, clean, and the handles in good repair.
Broken or cracked handles are to be replaced.
Mushroomed heads on chisels and punches must be ground off as flying pieces of steel can cause serious, even fatal injuries.
Each member of the survey crew shall assure that all miscellaneous tools are returned to the vehicle and put in their proper place prior to leaving the work site.
14.
Vehicles - The care, organization, and general housekeeping of a vehicle are good indications of the attitude of the entire crew.
Keep the cab and passenger compartment free of unnecessary clutter and equipment.
Store all equipment in designated places in compartments.
Any equipment or material stored in the passenger compartment should be neatly and firmly secured.
A good rule to follow is "A place for everything and everything in its place." Vehicles must be kept in good running condition.
A regular maintenance program for the vehicle is essential.
Needed repairs should be taken care of as soon as possible.
Driving in a safe and defensive manner is required of employees operating state vehicles and of contract consultant survey crews.
1.2.9.
Calibrations
1.2.9.1.
General
A calibration check on all types of electronic survey instrumentation is essential to obtain and maintain the tolerances required in this manual.
At the beginning of any survey all survey equipment needed to perform the survey shall be calibrated by the professional land surveyor in responsible charge of the survey under his/her direct supervision and/or checking.
All survey equipment shall be calibrated once every six months thereafter and as needed during the course of the survey, whichever comes first.
1.2.9.2.
Calibration Baseline Check
There is a cooperative program that provides surveyors with a means for checking and calibration of errors in electronic distances meters (EDM).
Publications are available for the procedures for checking of EDM against a Calibrated Baselines.
The unadjusted baseline length accuracy tolerances shall meet or exceed the manufacturers ratings for the equipment used when checked against a calibrated baseline length for both horizontal and vertical.
The checking and calibration of an EDM involves the determination or verification of instrument constants and the assurance that the measured distances meet required accuracy specifications.
Although it is not necessary to utilize a measured distance to determine or verify instrument constants, the verification effort is reduced when an accurately measured distance can be used.
However, to assure that the measuring capabilities of an instrument have not significantly deteriorated, a known distance of high accuracy or, preferably, a sequence of distances forming a calibration range or base line is required.
Experience shows that a base line consisting of four on-line
3 October 2013
7

Section 1: Survey Works
Preliminary Survey
monuments spaced at intervals of 150 m, 400 to 430 m, and 1000 to 1400 m will meet the needs of users for the checking and calibration of EDM.
The basic procedures to perform a calibrated baseline check of GPS equipment in RTK mode is as follows:
1.
A base receiver is setup on any one of the calibrated baseline marks.
2.
A rover receiver collects data at each calibrated baseline mark with the same equipment configuration (i.e.
elevation mask, epochs, sync time, maximum PDOP, satellite tracking, session duration, etc.) and methods that will be used for performing the survey.
3.
After the rover has collected data at each calibrated baseline mark the base receiver is moved and setup on each calibrated baseline mark and the rover collects data at each calibrated mark.
4.
This procedure is repeated as many times as needed until both a base and a rover receiver have occupied all calibrated baseline marks and data has been collected at all calibrated baseline marks.
5.
The data is downloaded into the GPS processing software with the same procedures and settings that will be used for the survey.
6.
The unadjusted baselines lengths and vertical differences are calculated and compared to the published calibrated baseline lengths and vertical differences.
7.
For the equipment to be considered as being in adjustment the final unadjusted baselines lengths and vertical differences shall meet or exceed the manufacturers ratings for the equipment.
1.3.
PRELIMINARY SURVEY
When a project has been identified to be built, a survey has to be completed to select the route, to locate existing features of the route, to identify areas of environmental impacts, to identify areas of Right of Way acquisition, to help to determine the costs of the project and to design the project.
There are several types of preliminary surveys that may need to be completed prior to design and construction of the project as follows:
1.
Reconnaissance Survey
2.
Control Survey
○ Horizontal
○ Vertical
• Right of Way Survey
• Preliminary Right of Way
• Final Right of Way
• Topographic Survey
1.
Drainage Survey
2.
Utility Survey
3.
Staking for appraisal
1.3.1.
Presurvey Conference/Preliminary Survey
Prior to beginning any preliminary survey activities a Presurvey Conference for Preliminary Surveys shall be held.
Any known error or oversight on the plans or specifications shall be discussed at the presurvey conference.
The project manager shall notify all parties listed below at least two weeks prior to the presurvey conference.
The following individuals should attend the Presurvey Conference for Preliminary Surveys:
8
3 October 2013

Preliminary Survey
Section 1: Survey Works
• Region Survey Coordinator or designee
• Region Right of Way Plans Coordinator or designee
• Design Engineer or designee
• Project Manager or assistant Project Manager
• Hydraulic Engineer or designee
• Bridge Engineer or designee
• Environmental Manager or designee
• Resident Engineer or designee
• Survey Crew Chief
• Any appropriate subcontractor personnel
If the preliminary survey work is to be performed by a contract consultant, either as a prime or sub-contractor, the professional land surveyor who will be responsible for the survey work performed shall attend the presurvey conference.
If the contract includes design processes, the contract consultant should be strongly urged to send the design engineer who will be responsible for that portion of the work.
The presurvey conference should be held at the site of the proposed project, or a tour of the area to be surveyed should be scheduled in a timely manner that is mutually convenient to all attendees.
All those attending the presurvey conference shall sign the Presurvey Conference Agenda and indicate whether or not they toured the site of the proposed work.
The surveyor in responsible charge for the survey work shall have the following reference materials at the Presurvey Conference for Preliminary Surveys:
- Project Plans if available.
• Preliminary Survey Scope of work
• Standard Specifications for Road and Bridge Construction.
• Right of Way Manual if Right of Way is required
• Manual of Uniform Traffic Control Devices (MUTCD)
One of the primary purposes of the presurvey conference is to delineate the requirements and limits of the upcoming survey.
While precise horizontal and vertical control may not be necessary for a simple pavement overlay, it may not be obvious that this control may be required for the design and construction of structures.
The presurvey conference provides an opportunity to determine the type and amount of survey activities to be done, and will prevent over-surveying as well as under-surveying of the project.
1.3.2.
Reconnaissance Survey
A reconnaissance survey in highway engineering is divided into two parts, a survey of the area and an evaluation of the feasible route alternatives.
The recon naissance survey of the area is the examination of a large area to determine the feasible highway corridors between the designated termini.
The evaluation of the feasible route alternatives is a comparison of those corridors in sufficient detail to select the corridor along which the highway should be built.
For reconnaissance, horizontal and vertical
3 October 2013
9

Section 1: Survey Works
Preliminary Survey
information about the area is needed as well as information about cover and culture.
This information can be obtained by field surveys; or it can be extracted from aerial photographs, from existing maps, or from maps compiled specifically for the project.
1.3.2.1.
Reconnaissance on Vertical Aerial Photographs
The most efficient method of highway reconnaissance is done directly on vertical aerial photographs at scales in the general range of 1:10,000 to 1:50,000.
New photography may be taken for the purpose, or existing photography may be used, supplemented by new photography where coverage is incomplete or where details have changed significantly.
Although a vertical aerial photograph is not a map because of displacement due to relief, it represents the surface of the earth accurately enough to find the best corridor for the highway.
Topography, geology, land use, soils, ecology and other features are immediately evident or are readily interpreted by stereoscopic examination of the photographs.
Elevations are easily derived from parallax measurements on the photographs.
Horizontal distances measured on the photographs are converted to ground distances using local scales determined by parallax measurements.
If topographic maps of the area are available, elevations and distances may be extracted from them.
The locating engineer studies the area carefully and finds each feasible route by which the designated termini may be connected.
Using qualitative and quantitative information he extracts from the photographs, the locating engineer delineates on the photographs the best location along each alternative.
After the reconnaissance is complete and the alternatives have been drawn in stereoscopic correspondence on the photographs, a set of the photographs is assembled into a mosaic which becomes the record of this part of the work.
1.3.2.2.
Reconnaissance on Existing Maps
Topographic maps prepared by some other agency for general use or for other purposes, at scales as small as 1:20,000, may be useful for reconnaissance, depending on the planimetric detail of the map as compared with the complexity of terrain and land use.
Such maps may be supplemented by existing vertical aerial photography.
1.3.2.3.
Reconnaissance on New Maps
Maps at scales of 1:5,000 to 1:10,000 may be compiled especially for reconnaissance of an area.
Such maps are useful, but it is difficult to justify the effort and cost of producing them unless they will also serve other purposes, since the reconnaissance could have been done directly on the photography from which the maps were compiled.
1.3.2.4.
Comparison of Alternatives
After all feasible highway corridors between the project termini have been determined by use of aerial photography and/or topographic maps, the alternatives are compared.
For each section, an estimate is made of construction cost, maintenance cost, and vehicle operation cost.
The service afforded by each alternative is evaluated as well as environmental, economic, and social impacts.
Based on all of these factors-impacts, service, and cost--one alternative is chosen, the corridor along which the highway will be designed and built.
Only when two alternatives are so nearly equal in all factors that a choice is difficult, is it necessary to refine the calculations by compiling preliminary maps and making preliminary designs.
In urban areas, preliminary mapping and design
10
3 October 2013

Preliminary Survey
Section 1: Survey Works
may be necessary to fully evaluate the service afforded by each alternative and to assess the impacts.
1.3.3.
Research
1.3.3.1.
General
The location, re-establishment, and perpetuation of land corners involving highway Right of Way are of the utmost importance to the department and to the public.
If any of these corners are incorrectly positioned, the resulting disruption of property boundaries could result in costly litigation.
The research performed before and during the preliminary phases of a project will determine the quality of the finished product and the costs related to the project.
Improper research may result in needless delays and add substantially to the costs of a project.
For CDOT purposes, the following requirements for research shall apply:
1.
Investigate thoroughly
2.
Perform a careful and diligent search
3.
Make studious inquiry or examination; investigation aimed at the discovery and interpretation of facts, revision of accepted theories or laws in the light of new facts or practical applications of such new or revised theories or law.
1.3.3.2.
Types of Research
It cannot be overstated that the proper research will result in a better all around project and it will make your survey analysis more secure.
You may find in your research that you may not utilize information or monuments currently in use, or will end up working with a completely different set of data and monuments as the requirements of research implies.
Always keep an open mind to allow for the inclusion of new data and information discovered by your research.
Research can be broken into two phases as follows:
• Office Research (e.g.
records)
• Field Search (e.g.
physical evidence)
The office phase is that portion of the research performed in your office or somebody else's office to gain information of record regarding boundaries, Public Land Survey System (PLSS), Rights of Way, property boundary, easements, points etc.
The field search is the recovering and locating of physical evidence of these items by finding and locating survey monuments such as PLSS, Right of Way, property boundary, easement, etc.
1.3.3.3.
Office Research
As much of the office research should be conducted by the surveyor in responsible charge as possible.
The office phase of the research consists of contacting various agencies that may have information of record such as deeds, subdivision plats, land survey plats, Bureau of Land Management (BLM) plats, mining claim maps, monument records, etc for the area affecting the project.
The primary source of property records is the county office of the clerk and recorder in which the subject property is located.
Although limited, some county offices are making their records available online through the Internet.
Once the researcher has been to this office, the following county agencies will usually be able to provide useful information:
3 October 2013
11

Section 1: Survey Works
Preliminary Survey
- Assessor's office: current landowner's information with their address and a brief description of the property.
- Clerk and recorders office: copies and original deeds, documents, subdivision plats, land survey plats and monument records.
- County commissioners records: information on road petitions, commission decisions, rulings, agreements, etc.
- Court records: information on court decisions, rulings, and court ordered surveys, etc.
- Engineering records: information on public works projects involving Right of Way.
- County surveyor's office: information on Right of Way, easements, land survey plats, boundary disputes, etc.
Some cities and counties have their own engineering departments and/or survey crews.
These municipalities have information on Right of Way, easements, section corner locations, benchmark, block and lot corners within a subdivision, etc.
Title companies also have some of the above stated information that the county clerk has.
Utility companies have information on their Right of Ways, easements, type of utility and purpose.
Irrigation companies have information on ditch names, flow quantities, capacities, names of individuals served by ditches in their area.
Landowners, surveyors, consultant firms, and other individuals may have a vast knowledge of land corners, surveys, subdivisions, and other engineering projects.
All of these sources and others not mentioned are potential research sources for the project.
This list should be used as a tool to check possible research sources, avoid overlooking obvious sources, and identify new sources.
As many of these potential sources as possible should be checked prior to any fieldwork.
Sometimes the checking of one source may lead you to another source and so on.
1.3.3.4.
Field Search
After the office research is conducted a field search shall be performed to locate all possible physical evidence that may exist in the field.
The field search shall consist of a search for existing survey monuments identified by the office research.
A few examples of the office research material used during the field search are as follows:
- Ties from previous surveys (e.g.
subdivision plats, land survey plats, deeds, easements, mining claim maps, Work Program of America (WPA) ties, etc)
- BLM notes and plats
- Monument records
• Right of Way plans
- Construction plans
- Railroad maps
- Topographic maps
- Aerial photos
- Assessors maps
- Other maps
- Parole evidence
12
3 October 2013

Preliminary Survey
Section 1: Survey Works
All found monuments and physical evidence found shall be located and tied into the Primary Control Monumentation for the project in accordance with the appropriate Minimum Horizontal and Vertical Accuracy Tolerance for the type of survey being performed.
The following should be used as a guide in field search:
- Reference / accessory ties from monument records for PLSS land corners to verify the corner.
Any discrepancy shall be noted.
- If nothing is found using ties, check for the point using a metal detector.
A search of road intersections, fence corners and other areas where land or property corners may exist is sometimes productive.
- If nothing is found excavation of the area may be necessary.
Excavation should be such that either the point is recovered or determined not to exist at that location.
Whatever means are used; care should be exercised to prevent damage to the point.
Excavation should be limited unless evidence indicates a corner may exist, such as reference ties on poles or by metal detector.
Photos should be taken of any recovered evidence and should show the found evidence's relationship to occupation lines and other physical evidence to help aid in the re-establishment of the monument in the event it is lost in the future.
Any damage caused by excavation shall be repaired immediately.
1.3.4.
Drainage Survey
1.3.4.1.
General
The purpose of a drainage survey is to ensure that the necessary information needed for hydraulic design will be included in the topographic survey.
The following guidelines shall be followed when drainage surveys are conducted:
The Preliminary Survey Scope Form shall include all drainage structure requirements of the survey.
This form shall be supplemented or confirmed through direct contact with the hydraulic engineer.
The project manager should contact the hydraulic engineer at least two weeks prior to the presurvey conference.
After the survey requirements have been determined and included on the survey scope, a transmittal of the requirements will be submitted to the Region Survey Coordinator.
Following these guidelines will provide the hydraulic engineer with an adequate drainage survey.
If there are any questions about the needed information, the hydraulics engineer should be contacted before starting the survey.
The hydraulics engineer will be able to supply predicted design flows, special survey requirements, and potential use of upstream area for detention ponding.
Good drainage surveys are necessary for complete hydraulic designs.
Channel locations and changes, bridge skew, water stage, and structure relocations are all determined from the drainage survey.
1.3.4.2.
Aerial Photogrammetry Methods
An aerial photogrammetry survey method utilizes photographic, electronic, digital or other data obtained from an airborne station (e.g.
a airplane or helicopter).
The advantage or obtaining topographic data by aerial survey methods is the efficiency in which large areas of the Earth can be mapped and large volumes of topographic and planimetric data can be obtained.
The disadvantage of aerial mapping is that it requires more advanced planning and lead time than conventional or GPS survey methods.
The
3 October 2013
13

Section 1: Survey Works
Preliminary Survey
accuracy of aerial surveys are typically much less than that of conventional or GPS survey methods, particularly when there is heavy vegetation or areas of drastic changes in elevation such as mountainous terrain.
Drainage surveys are performed to supplement aerial surveys.
The purpose of the supplemental survey is to locate those features that require a higher level of accuracy than that of the aerial survey, to locate those features that can not be located by the aerial survey, and to collect information not apparent to the photogrammetrist from the aerial survey.
1.3.4.3.
Photographs
If the hydraulic engineer deems photographs necessary, they will be requested in the drainage survey requirements transmittal.
When requested, photographs shall show existing inlet and outlet configurations, areas of erosion, structures that experience distress during floods, and natural features of the drainage basin.
Photographs shall be labeled with the project number, date of photo, description of photo, orientation of the camera, and the photographer's name.
1.3.4.4.
Guidelines
Guidelines for the extent of a drainage survey upstream and downstream are as follows:
- Large Bridges [Design flows greater than 566 m\( ^{3} \) spans greater than 76 m]
a.
Consult with the hydraulics engineer before scoping the survey.
Requirements will be further discussed at the presurvey conference.
b.
Aerial surveys should be considered for these sites.
- Large Culverts/Medium Bridges [Design flows of 56.6 to 566.3 m\( ^{3} \) or 6 m×3 m Cross-section of Box Culvert (CBC) to 76 m Total Span Bridge]
- The survey shall extend 365.8 m upstream and 365.8 m downstream from the existing roadway centerline.
○ Additional survey data must be taken near the upstream and downstream edges of the existing structure including the abutments.
○ The elevations of the existing structures lowest girders or clearance must be included.
○ The width of the survey will be determined by the hydraulic engineer.
- Survey requirements will be discussed at the presurvey conference.
- Medium to Large Culverts [Design flows of 5.7 to 56.7 m\( ^{3} \) or 1.8 m Pipe to 6.1 mx3 m CBC (openings of 2.6 m\( ^{2} \) to 18.6 m\( ^{2} \).)]
The survey shall extend 152.4 m upstream and 152.4 m.
downstream from the roadway centerline.
○ Additional survey data must be taken near the upstream and downstream end of the existing structure.
○ The width of the survey will be determined by the hydraulic engineer.
- Survey requirements will be discussed at the presurvey conference.
- Small Culverts [Design flows less than 5.7 m\( ^{3} \) or pipes smaller than 1.83 m (less than 2.6 m\( ^{2} \) openings)]
○ The survey shall extend 30.5 m upstream and 30.5 m downstream from the roadway centerline.
14
3 October 2013

Preliminary Survey
Section 1: Survey Works
- Survey data must also be taken at each end of the culvert to determine the structure centerline, the depth of silt, headwall dimensions or type of end section, condition of the present structure, type of flow, vegetation and soil type of banks and bottom.
○ Discuss further needs at the presurvey conference.
- Irrigation Canals
The water surface profile and the channel invert must both be surveyed.
This may result in two separate surveys, unless the surveyors could mark the water surface elevation during flow and take the measurements at a later date when the canal is not in operation.
The survey shall extend 305 m upstream and 610 m down stream from the roadway centerline.
The downstream portion of the survey will not need to extend the full 610 m if a difference in the water surface elevation of 152 mm has been achieved.
Measurements of the water surface profile shall be taken at 30.5 m intervals to +/- of 15 mm.
The date and time of the water surface profile shall be recorded.
○ Name and address of the ditch owner should be noted.
Inquire as to the discharge at the time of the water surface profile.
This information should be available from the ditch rider.
○ If the Department's liability is lessened by using the ditch company's water flow information this should be the procedure used to determine the water surface profile.
- Storm Drains
Survey data must be taken of the profile grade and gutter flow line elevations of the main roadway.
The survey must cover all areas of the roadway that contribute drainage.
This may entail surveying beyond the project limits.
For example, if the project ends in the middle of a vertical curve, the survey must continue to the top of the curve.
Survey data must be taken of the profile grade and gutter flow line elevations of all cross streets or road approaches.
The survey shall extend up the road approach or cross street 152.4 m or to it's highest point, whichever is less.
The location of all curbs, gutters, inlets, culverts, and manholes must be determined.
Indicate inlet and pipe depths and sizes (rim and invert elevations).
Note the direction of flow in the pipes.
The location of all utilities must be determined.
Indicate the type, size, and depth of the utilities.
• Existing Upstream Detention Ponds
- Detention pond surveys must be accurate enough to draw a contour map with three to five contours.
- The survey data shall extend up to an elevation equal to the pond overflow elevation.
Show any significant topography within the ponding area, such as building foundations, ground floor elevations, and outlet structures.
3 October 2013
15

Section 1: Survey Works
Construction Survey
1.3.5.
Utility Survey
The purpose of a utility survey is to gather data of underground and above ground utilities.
This is typically accomplished during the topographic survey.
Utility surveys include both above, and below ground utilities as required on the Preliminary Survey as follows:
- Gas
- Transmission
- Electric
- Telephone
- Water
- Sanitary
- Television
- Pipelines
- Irrigation
- Fiber Optics
- Etc.
Architects, engineers, or other persons designing excavation shall obtain general information as to the description, nature, and location of underground facilities in the area of such proposed excavations and include such general information in the plans or specifications to inform an excavation contractor of the existence of such facilities.
1.4.
CONSTRUCTION SURVEY
The construction survey delineates the designed highway on the ground as construction proceeds and provides measurements to compute quantities for payment.
1.4.1.
Location Survey
Once the highway& bridges has been designed, the horizontal and vertical alignment and cross-section data in the plans must be transferred to the ground so the highway can be constructed.
The location survey does this by placing enough properly marked stakes in the ground to delineate the highway as designed.
If full use has been made of photogrammetry, this is the first time that a surveyor with an instrument has been on the project since completion of the basic control survey.
The location survey includes the centerline survey, profiling the line, slope staking, staking of structures, and placing of grade stakes.
1.4.2.
Centerline Survey
The centerline survey marks on the ground the horizontal position of the highway centerline.
Unlike the basic control survey, which is a determining survey (see Introduction, Ground Surveys), the centerline survey is an establishing survey.
The basic control survey determines the coordinate position of station markers placed in the ground; the centerline survey establishes points representing the designed centerline by transferring to the ground (at 1:1 scale) the alignment information furnished by the plans.
The centerline survey is a traverse survey controlled by the basic control survey.
16
3 October 2013

Construction Survey
Section 1: Survey Works
Points of intersection (PI) are located by angle and distance from basic control point monuments (backsighting on other basic control survey monuments).
Tangent distances and angles at points of intersection are checked.
If they meet the standard of accuracy of the location survey, the ends of the centerline tangent are established and station marking stakes are placed at regular intervals.
Spirals and circular curves are then staked.
Referencing of centerline points, as required, completes the centerline survey.
Centerlines cannot be established to the accuracy of geodetic traverse surveys.
To establish a point, a backsight is taken, the required angle is turned on the instrument, and the line of sight is marked, with the telescope "upright" or "direct." The same procedure is repeated with the telescope "inverted" or "reversed." This complete procedure may be done a second time to isolate blunders.
The point is established halfway between the two marks or at a point representing the average of the set of marks.
Further repetitions of the process add little to the accuracy.
The points along the centerline which define a curve are established in line with a transit or theodolite and in stationing by chaining with a steel tape or by an electronic distance measuring instrument.
When using the steel tape, the point is usually established by a first measurement and checked by a second measurement.
When using an electronic distance measuring instrument, two points are established, one ahead of and one behind the curve point, and its final position is established by graphical interpolation.
Setting of station stakes along the curve is usually to a lower standard of accuracy than that used for establishing of the points which define the curve.
A single measurement with a steel or reinforced cloth tape usually is sufficient.
1.4.3.
Profile
Level circuits for the centerline profile are run between basic control survey bench marks.
Ground elevation is measured at each centerline stake.
In areas where the ground surface is not well defined or where it may change rapidly, as in swamps or in loose sand, a stake or hub, long enough to be firm when flush to the ground surface, is driven in front of the centerline stake, and its elevation is used as ground elevation.
From the ground elevation at the centerline stake is subtracted the designed centerline grade for the station to compute the cut or the fill at that point.
The cut or fill is usually written on the back of the centerline stake.
Stakes must be added where there are abrupt changes in the ground level or changes in the designed cross sections.
Stakes must also be added where earthwork at a shoulder line changes from cut to fill or from fill to cut.
1.4.4.
Slope Stakes
Slope stakes delineate the designed highway on the ground for construction.
The actual setting of the slope stakes may be done concurrently with the measuring of the profile or it may be a separate operation.
If the ground is fairly level, the same instrument and setup which was used to measure centerline profile elevations may be used to measure the elevations necessary to set the slope stakes.
In rougher terrain, elevation may be transferred from centerline station to slope stake position by hand level, reducing arc, or a "total station" type instrument.
Two slope stakes are set for each section, at the toe of the fill slope or the top of the cut slope on each side.
An approximate location is usually available or can easily be computed from the design data-the plotted or computed cross sections.
A point is found on a line perpendicular to the centerline and at the distance shown by the design data.
3 October 2013
17

Section 1: Survey Works
Global Positioning Systems (GPS)
The cut or fill of this point is measured.
If it agrees with the computed cut or fill, the slope stake is driven there; if it does not agree, other trial points are measured until the location of the toe of the fill or the top of the cut slope is found.
1.4.5.
Structure Stakes
Special staking is necessary for each structure -bridge, tunnel, culvert, retaining wall, or others.
These range in complexity from high order traverses for a major bridge or tunnel to simple marki

…(209,422 more chars)