Q U A L I T Y IN C O N S T R U C T E D P R O J E C T :

SURVEYING ENGINEERING a
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By Gunther Greulich, ~ Member, ASCE,

Wayne H. Valentine,2 Fellow, ASCE,
and R. R. Chamard, 3 Affiliate, ASCE

ABSTRACT; Surveyingengineering is an essential ingredient to the assurance of

quality in a constructed project. This paper addresses the responsibilities and tasks
required prior to and during the constructed project. Project concept, planning,
design, and the construction phase of a project in each phase does need special
surveyingconceptsand specifications. Specificsurveyrequirements are defined and
detailed for each phase. The need for peer reviews in establishing engineering
survey requirements vary by the type of survey needed during the work phase. A
construction project is not completed until proper postconstruction surveys and
documentation is complete. The paper details project minimum requirements and
their long-range importance in the life of a completed project.

INTRODUCTION

Almost all the authors of Volume 1 of Quality in the Constructed Project

have stressed the importance of planning for quality from a project's very
beginning. Quality must be integral with the project long before construction
begins. Quality construction is based on solid foundations; surveying en-
gineering provides one of those foundations. Bench marks and base ref-
erence lines are vital components of a three-dimensional framework of
spatial reference points without which quality construction is not possible.
Volume 1, chapter 9, "Planning and Managing the Design," describes
and warns that project quality is threatened by overlooking existing site
conditions, e.g., buried facilities. Quality is threatened when the original
data gathering team is unfamiliar with design considerations. Quality is also
threatened when the importance of finding reliable data before construction
is underestimated, and the job is assigned to unqualified personnel.
Chapter 9 lists the first of four steps in value engineering as the infor-
mation phase. The first step consists of gathering information, and it is in
this step where the foundation to quality and success is established or de-
veloped. Survey engineering is performed in the "gathering of information"
stage.
Without surveying, there can be no construction. Before, during and after
any construction project, regardless of size or complexity, measurements,
revisions, and adjustments are necessary. Data acquisition, construction
layout, postconstruction, and monitoring surveys are key functions of sur-
veying engineering. They are vital to the success of any construction project.
The quality of their execution contributes to the quality of the construction

"Chapter 10, "Survey Engineering," of Volume 2 of Quality in the Constructed

Project.
1Gunther Engrg. Inc. 263 Summer St., Boston, MA 02210-1506.
2Consultant, 5535 N. Citadel, Boise, ID 83703.
3Skyjette Consultants Inc., 445 Palomino Drive, Eugene, OR 97401-6617.
Note. Discussion open until October 1, 1994. To extend the closing date one
month, a written request must be filed with the ASCE Manager of Journals. The
manuscript for this paper was submitted for review and possible publication on
August 30, 1993. This paper is part of the Journal of Surveying Engineering, Vol.
120, No. 2, May, 1994. 9 ISSN 0733-9453/94/0002-0052/$2.00 + $.25 per
page. Paper No. 6871.
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J. Surv. Eng. 1994.120:52-61.

 project from its beginning through its completion, and into management
and maintenance phases of the project's life.
Survey engineers are professional specialists on the design/construction
team who are responsible for these essential tasks. The survey engineer and
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surveyors help guide construction to its successful conclusion, and provide

reliable location data for as-built surveys, so important for maintenance,
operation, and future extension or modification of constructed projects.
Survey reliability often depends on the fee the project owner is willing
to pay for these professional services. Survey errors sometimes are not
detected until after construction begins. High-quality control surveys are
sound investments that often eliminate or at least minimize extra costs for
redesign, removal of structures placed in wrong locations, reordering pre-
fabricated components such as beams or pipes, and other modifications.
The fee for a reliable survey by a competent survey engineer is far less than
the cost for construction extras due to survey errors. Seldom do such fees
exceed 1% of the total development cost. Unlike some other construction
tasks of comparable expense, survey control and survey data affect the entire
construction and postconstruction process. Important design, finance, legal,
and construction decisions are based on survey results. A quality survey is
always worth the expense. The following sections will elaborate on survey
reqmrements, methods, and standards to support successful construction
projects of high and lasting quality.

RESPONSIBILITIES

Responsibility for surveys for engineered construction must be assigned

to professionals who, by education, experience, and registration or certi-
fication, are competent to perform, or provide responsible charge over,
survey activities.

Control and Geodetic Surveys

Every project, whatever its complexity, requires a framework of spatial
reference points for layout, control of construction, and postconstruction
activities. For very small construction projects, these control points may be
embodied within the structure or project itself, e.g., the as-built foundation
of a small house can provide the reference framework for the rest of the
structure. But the larger the project the greater the need for extensive,
accurate, and specially monumented control networks. For large, complex
projects the surveyed control network should be connected to a geodetic
reference system. The survey engineer making this connection must be
aware of the different data, projections, and spheroids employed at various
locales and dates. The engineer must also select proper surveying methods
(i.e., trilateration, triangulation, traverse, satellite positioning, photogram-
metry), and be aware of precision requirements for construction and
postconstruction monitoring.
Design and survey of control systems should be performed by or under
the direction of engineers who are competent in performance of these sur-
veys and knowledgeable in construction processes to be used and measure-
ment precision needed to control them.

Property Boundary and Right-of-Way Surveys

All states regulate the practice of land surveying by licensing or registering
land surveyors. Title and easement lines defining limits of the property on
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 which the project is to be constructed should be researched, described if
necessary, and laid out by a land surveyor duly registered to practice in the
jurisdiction. Boundary and right-of-way surveys should be connected to the
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construction control and geodetic networks.

Mapping and Charting Surveys

Site maps prepared by photogrammetric methods should be performed
by photogrammetrists certified by the American Society for Photogram-
metry and Remote Sensing (ASPRS). Maps prepared by "total station" or
plane-table methods should be performed or supervised either by registered
land surveyors or by registered civil engineers.
Charts for marine construction and operation should only be prepared
by engineers who have specialized experience in hydrographic surveying.

Construction Surveys
Construction surveys are for controlling construction operations, includ-
ing earthwork and placement of elements of the work to line and grade,
checking construction progress, and measuring quantities (e.g., earthwork)
for payment. Only competent survey engineers should make or be in re-
sponsible charge of such surveys.
This category also includes surveys of underground works such as tunnels
and mines. Surveys of these works require surveying mining engineers with
expertise in this specialty.

Postconstruction and Monitoring Surveys

Postconstruction surveys are conducted to assess performance of struc-
tures under load and to assess the capacity and condition of older structures.
These surveys are performed by conventional and photogrammetric meth-
ods. They usually require special techniques of measurement, adjustment,
and analysis to determine factors with validity. Only engineers with special
training or experience are competent to design and direct or perform these
surveys.

Peer Review
In case of a dispute between the constructor and surveyor concerning
survey problems, it is recommended that the owner and the design profes-
sional review the issues germane to the dispute.
An independent, reputable survey engineer should be retained to analyze
field notes, design drawings, computations, sketches, and as-built condi-
tions. Safety and quality of ongoing construction will be ensured. Good
record-keeping habits resulting in dated and signed field notes are essential.

SURVEY TASKS
Although surveying and measurements are consistently required through-
out the construction process, individual tasks vary with each phase.

Concept Phase
Every construction site has boundaries, both physical and legal. The
placement of proposed structures depends on the land parcel's geometry
and topography. Access and availability of utilities influence location de-
cisions. Ownership rights, existing easements, zoning requirements, prox-
imity to wetlands or flood hazard areas, harbor lines, air rights, mining
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 leases, the presence of known aquifers and other sensitive environmental
issues, all affect construction and should be thoroughly studied before design
and construction.
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Horizontal and Vertical Control

Diligent record research at public agencies and collection of data from
existing sources is a survey effort that should precede all field surveys.
Connections to geodetic control points should be obtained to ensure that
the construction project is related to a local plane coordinate system. In-
formation on official benchmarks obtained from local government engi-
neering departments will enable design professionals to relate proposed floor
elevations, pipe inverts, site grades, and other vertical data to the local
official datum.

Utilities
Researchers must gather information on location and size of existing
underground utility lines from public and private utilities before field sur-
veys. Not every manhole cover or other surface utility structure is readily
visible on the ground. In rural areas they may be overgrown and in urban
areas they may be paved over. Knowledge of what to expect may prevent
overlooking buried facilities, thereby removing a threat to the project's
quality. Knowledge of the location of hazardous elements, e.g., gas mains,
may even save lives.

Record Sources
There are many public and quasi-public agencies at local, state, and
national levels that maintain relevant land-information data. Among them
are municipal engineering departments, tax assessors, conservation com-
missions, building inspectors, zoning departments, planning boards, public-
works departments, metropolitan district commissions, transportation de-
partments, rapid transit authorities, railroads, utilities, airports, county en-
gineers and surveyors, county commissions, water boards, registers of deeds,
state public-works departments, environmental protection agencies, haz-
ardous-waste coordinators, the Corps of Engineers, the Bureau of Land
Management (BLM), the U.S. Geological Survey (USGS), the National
Geodetic Survey (NGS) of the National Ocean Service (NOS), the Federal
Highway Administration (FHA), the Federal Aviation Administration (FAA),
and many others.
Many sources must be contacted before the engineering survey for design
and construction starts. Awareness of existing codes and conditions can
prevent costly design changes. Timely collection of available data will ul-
timately enhance the quality of construction from concept through comple-
tion.

Planning and Design Phase

Engineering surveys are part of the first step of value engineering, de-
scribed in chapter 9 of Volume 1 as the "information phase." Acquisition
of actual field data by various methods includes ground surveys, photo-
grammetry, soundings, and even remote sensing.

Data Acquisition
Planning Data. Available U.S.G.S. topographic quadrangle maps and/
or vertical aerial photographs will satisfy the preliminary planning for large
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 construction projects. Remote sensing data obtained from satellites can be
helpful in planning construction projects covering large areas or long dis-
tances, such as highways and transmission lines. Traditional topographic
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field surveys, however, serve the same purpose more economically for small
sites. In addition, they have the advantage of being suitable for final design.
Design Data. Just as the pocket rule and steel tape have not been re-
placed by EDM (electronic distance measuring) equipment, so traditional
ground-survey methods will not totally be replaced by technologically ad-
vanced measurement systems. Ground-survey methods have improved con-
siderably in recent years. Stadia method (using plane table, alidade, and
stadia rod) for topographic surveys is being replaced by electronic data
collectors, commonly known as "total stations." X-, Y-, and Z-coordinates
of accessible physical points are rapidly located and recorded on magnetic
media in the field. The resulting magnetic data are converted by an office
computer into an accurate plot at a desired scale.
For design of larger projects, vertical aerial photogrammetry is recom-
mended. Existing uncontrolled aerial photographs previously flown for pre-
liminary planning purposes can be related to the ground coordinate system
to enable making of engineering measurements. This is done by horizontal
and vertical ground control surveys with analytical methods, with properly
planned aerial photography. Flight lines, altitude, photo scale, and overlap
are photogrammetric engineering elements that must be designed before
photography acquisition.
Photographic reductions of maps to enable presentation of larger areas
at smaller scales will not diminish the map's accuracy; however, enlarging
maps beyond their original designed scale can result in erroneous design
and expensive construction extras.
For many types of projects, a photogrammetric compiled map is important
for planning of a quality construction project. The information portrayed
on the map must not only be presentable and easy to understand, its data
must be reliable. A common mistake in photogrammetric mapping is im-
proper use of ground control; e.g., not enough or improper weighing of
control of variable quality. Inadequate ground control may make for a lower
cost map, but the map may also be useless for quality construction.

Survey Control
Although actual construction may not be imminent, the survey control
network and survey methods should be designed with construction in mind.
Whether the project is an apartment complex, industrial park, bridge, tun-
nel, highway, or utility corridor, a vertical control network should surround
the project. Surveyors should place well-spaced, semipermanent bench-
marks (a minimum of two for a very small site) along the perimeter but
away from proposed or anticipated construction activity. Elevations estab-
lished by vertical control survey should be based on an official datum.
A horizontal survey control network should also surround the construc-
tion site. Permanent monuments should be established for key control points.
Site sketches relating the survey monument to its surrounding physical fea-
tures should be made for future recovery. Despite the type or sophistication
of equipment, survey control points must be incorporated in closed loops
or verified by independent location. Reference to the local state plane
coordinate system (SPCS) (or another local geodetic system), is essential
for major construction projects, and is strongly recommended for all proj-
ects. Environmental concerns and permit requirements can be accommo-
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 dated more reliably when all horizontal and vertical surveys are related to
an official geodetic reference system.
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Reference Systems
Almost all official local horizontal and vertical systems on the municipal,
county, and state level are related or can be converted to the National
Geodetic Reference System (NGRS), maintained by National Geodetic
Survey (NGS).
The National Geodetic Vertical Datum of 1929 (NGVD 29) was formerly
known as the Sea Level Datum of 1929. The newest vertical datum is the
North American Vertical Datum of 1988 (NAVD 88). This datum ties all
previous reference systems together in on one coherent unified system for
North America.
Similarly, the official national geodetic network, known as North Amer-
ican Datum of 1927 (NAD 27) has been supplanted by the North American
Datum of 1983 (NAD 83), an improved system of greater accuracy.
Property boundary corners and highway layout lines also provide impor-
tant reference markers for proposed construction projects. In the Public
Land Survey states, county authorities and the Bureau of Land Management
(BLM) can provide valuable data on their recovered existing section corners.
Some counties are relating section corners to the NGRS. Elsewhere, the
BLM will provide corner coordinates, along with estimated reliability, from
the Geographic Coordinate Database (GCDB).
The NGS should be contacted for specific information and advice.

Construction Phase
Volume I stresses the need for team work in construction. The quality
of a project is enhanced when professional specialists are assigned tasks
compatible with their respective skill and knowledge. Surveying the physical
layout of structures is one of those tasks.

Construction Layout
Translating a blueprint to a location on the ground (layout) is an important
survey function. The construction manager must provide the project's survey
engineer with all relevant construction drawings before the surveyor visits
the site to perform the actual layout. Time, money, and work hours can be
saved, if sufficient time is budgeted to review and coordinate the drawings
in advance. Not every design drawing is complete and ready to be used for
layout. Critical measurements may be obscure, difficult to decipher, erro-
neous, hidden in detail sketches, shown on another sheet, or missing. By
allowing adequate time and using proper resources, these problems can be
resolved before the survey party arrives on the site. Managers can save time
and money, and may even prevent a disastrous construction mistake.
Expected accuracy for the location of structural components should be
discussed with the survey engineer before structural components arrive on
site. Not all design tolerances specified are realistic.
Survey engineering procedures incorporated early in the project will per-
mit timely and reliable relocation of vital horizontal and vertical survey
control points. Endangered survey control markers should be referenced
off-site before they are disturbed or covered. A bench mark saved from a
bulldozer may save more than just money. It will retain the vertical integrity
of the entire project by ensuring that constructed work is tied to an accepted
vertical datum.
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 Construction materials, equipment, site trailers, temporary fences, and
the future structure itself will disturb or destroy some points. They will
obstruct clear lines of sight between control points. The survey engineer
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should anticipate these inevitable occurrences and establish offsets and azi-
muth references as early in the project as possible.
An offset control "box" surrounding the structure to be built must be
double-checked and adjusted before using as the control for layout. A
construction control diagram showing and identifying baselines, centerlines,
range lines, targets, offsets, benchmarks, and ties to outside structures,
should be prepared and checked by the survey engineer. The plan should
be provided the construction manager, who in turn should provide other
site engineers and subcontractors with copies. The plans will allow construc-
tion engineers to recover basic control during construction. Supplemental
control points and lines for specific structural elements can be surveyed from
the basic control network and the plans will serve as a helpful guide for
checking and rechecking subsequent survey work.

Property Boundaries
Boundaries, whether they are lines dividing ownership or right-of-way
lines, ultimately determine where a structure may or may not be built.
Physical, legal, and mathematical location of boundaries must be known
before, during, and after construction to ensure compliance with the phys-
ical, legal, and mathematical constraints of the project.
Construction plans for quality projects should clearly depict boundaries
and their precise spatial relationship to the proposed structure. If these legal
lines are not sufficiently monumented so that they can be recovered and
occupied in the field by the surveyor, delays and extra costs are possible.
The registered land surveyor responsible for the property lines must be
identified on the site plan.

Construction Monitoring
In urban construction, existing buildings and structures surrounding the
project site are important aspects of the overall project. Obviously, they
must not be disturbed or damaged. Even when all precautions have been
taken, lawsuits for damages alleged to have been caused by construction
activity are possible. Defense against these contingencies will require evi-
dence, since courts are not likely to favor an unsupported case. Evidence
in the form of solid survey engineering data are required.
Settlement levels, crack surveys, alignment studies, and photographs of
surrounding buildings, taken before, during, and after construction, will
provide evidence. Off-site horizontal and vertical control monuments should
be preserved for continuous and reliable reference. Systematic record keep-
ing and preservation of field notes is vital.

Photogrammetric Surveys

Aerial Photogrammetry
Engineers have used photogrammetric techniques to produce maps and
charts for many years. This process uses vertical aerial photographs in an-
alogue and analytical stereoplotters to construct graphical and digital models
of the earth's surface.
Photogrammetrists should make a distinction between mapping, to pro-
duce graphical models; and measuring, to produce coordinates or dimen-
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 sions in two or three axes. High-quality, consistent measurements are re-
quired for engineering purposes. Analytical systems to make measurements
on photographs and with advanced adjustment software easily produce pre-
cision measurements from all types and scales of photography.
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Close Range Photogrammetry (CRP)

The use of photographs in a non-aerial mode is called terrestrial, non-
topographic, or close-range photogrammetry. Engineers are using CRP in
planning, design, construction, documenting, and monitoring. Examples of
its accepted uses are:

1. Mapping building facades.

2. Measuring structural deformations.
3. Mapping archaeological sites.
4. Measuring features on underwater structures.
5. Analyzing roadway pavement textures.
6. Monitoring tunnel alignments.
7. Surveying as-built intricate piping installations.
8. Monitoring retaining wall movements.
9. Monitoring ship or other large vessel modules.
10. Mapping intricate shapes or surfaces.
11. Providing visual records.
12. Providing records for historic structures.
13. Measuring contaminated, hot, or other hazardous objects.
14. Measuring effects of dynamic loading.

The planning process for CRP is critical. Each application is unique and
requires close communication between the project owner and survey en-
gineer. CRP uses photographs taken at predetermined positions. The pro-
cess is much like measurements taken with theodolites in triangulation, in
that the photographs should be in known positions or the distance between
photographic stations needs to be known. CRP incorporates the following
steps.
Planning. The required measurements, their accuracies, and data output
needs must be determined for the project. Measurements can be recorded
as hard copy (maps, charts, profiles) or as digital data for use in computer-
aided-design (CAD) systems. To achieve specified accuracy it is necessary
to determine the type of camera to be used. Where accuracies required are
low, e.g., 1 part in 1,000, 35-mm or 70-mm cameras are adequate. If higher
accuracies are needed, special calibratedj larger-film-format metric cameras
are necessary. A determination of the type of equipment that will be used
to make measurements on the photographs must be made at the planning
phase, since that equipment will have an effect on the positioning of the
camera station locations. Accuracies can be as high as 1 part in 250,000 of
the camera distance from the object being measured.
Control. The control aspect of CRP involves determining the location
of camera stations and their relationships to each other and the surface or
object to be measured. Output quality is directly related to control. Control
for CRP may be provided by known positions in the object space, or by
determining the position and orientation of cameras, or a combination. If
targets (readily identifiable artificial points) with known positions are placed
on the object to be measured, then camera relationships can be computed.
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 In cases in which a high degree of accuracy is not required, only relative
camera positions and object distance are needed. Although targets are not
required, redundancy of control in any project, especially if cost is small,
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is desirable. Control redundancy helps detect blunders and provides security

for lost points.
Exposing Photographs and Processing Film. Most engineering survey
projects using CRP will be of a stationary object. The photography process
requires positioning the camera on a suitable platform and exposing the
film. To simplify the measuring process, the survey engineer should deter-
mine that the camera is in the proper location and that the orientation is
recorded.
Generally, black and white film is preferred, and exposures should pro-
vide for shadow penetration. Adequate coverage of the object or site is
essential, as is a clear view. Objects that obscure the scene must be removed.
Processing should be performed by reputable labs using chemistry recom-
mended by the film manufacturer.
Measurements and Data Reduction. Photograph measurements can be
made on many commercially available instruments. These instruments can
vary from analytical and analogue stereoplotters to simple digitizing tables
connected to personal computers. Measurements can be made in model
space or separately on the overlapping photos, and coordinates determined
by computation. Either method develops three-dimensional coordinates of
the measured point.

Summary
Close range photogrammetry has been used extensively for construction
monitoring and for developing plans for building restoration, especially in
Europe. Its application is especially helpful where conventional field surveys
are difficult or hazardous to conduct. For example, CRP is often the only
reasonable technique for surveying inside contaminated nuclear facilities
and hazardous waste dump areas. Some advantages of CRP over other
survey methods are that it:

1. Provides a permanent record for future examination,

2. Allows measurements in hazardous environments.
3. Provides solid evidence for courts of law.
4. Allows for data acquisition with a minimum of construction disruption.

CRP is becoming a more common engineering surveying technique and will

enhance both quality and safety in construction.

Postconstruction Phase
Post construction or as-built surveys are needed to establish an accurate
record of constructed works. The purpose is to determine the three-dimen-
sional position of elements for management, maintenance, and possible
future modification. Results should be displayed on an as-built plan at an
appropriate scale, either in hard or soft copy.

As-built Surveys
Changes to designs virtually always are made during construction. The
nature, extent, and location of these changes must be properly recorded for
future needs. The exact constructed location of surface and especially un-
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 derground facilities must be known for proper protection, maintenance,
modification, repair, and eventual replacement or demolition.
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As-built Records
Designers and project managers should include as-built survey require-
ments in their planning, budgeting, and execution plans of engineering
projects. Public-works departments and plant facility engineers should re-
quire as-built surveys and documentation for all new facilities within their
jurisdictions, and should also maintain current files of as-built plans.
Accuracy should be consistent with actual requirements but not less than
state and local statutes. Surveys should be reliably referenced to either
survey monuments or an established geodetic survey network. Monuments
may be property boundary monuments, right-of-way monuments, or marks
specially set for the project.
These surveys should be supervised by registered professionals, and bear
the seal, signature, and certification on final documents. Certification such
as "I hereby certify that all surface structures and underground facilities
shown have been located in the field and this survey reflects their as-built
location" should appear on final hard-copy drawings or plans.

SUMMARY
Reliable surveys are a essential for quality construction, even though
project teams may not understand their importance. The survey plan pro-
vides the basis for many legal, design, finance, and construction decisions.
Quality construction is difficult or impossible to achieve without quality
construction surveys. The surveyor must be a member of the construction
team throughout the project. Early selection of and good communication
with competent survey engineers will contribute to successful completion of
a quality project.

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