Geodetic References: Datum

In order to determine the locations on the surface of the earth, we need to choose a mathematical form that expresses the shape and size of the earth itself, which we call the name Reference Surface. One of these reference shapes might be the sphere, which has long been used to find locations that do not require great precision and to generate maps with a scale of no more than 1:1 million. In addition, for relatively small regions (less than 50 square kilometers), the (Plane) form can be used as a reference, particularly in (Surveying Plane) applications. The ellipsoid is the reference shape used for high-accuracy positioning or generating accurate maps.

Geodetic Datum

Geodesic experts have made numerous attempts over the last two centuries to discover the most appropriate ellipsoid that best depicts the shape of the earth. And, as fresh geodetic measurements are collected by scientists or international agencies, new values for the elements of the definition of ellipsoids (whether b, a, or f, a) are calculated, resulting in the existence of numerous ellipsoid models.

Each country, when first creating its geodetic or cadastral structure in order to begin producing maps, frequently chose the most recent ellipsoid available at the time to serve as the reference surface for its map system. If another ellipsoid developed after a few years, this country would be unable to alter its reference surface and replicate and publish all of its maps for technological and material reasons. But what is the reference? Any ellipsoid is known to be as close to portraying the surface of the planet as possible at the global level; that is, the differences between it and the geoid vary from place to place on the earth's surface, but they are the smallest possible at the global level. When a country chooses a particular ellipsoid, it wants the difference between it and the geoid to be as small as possible within its boundaries, regardless of how large the deviations are in other parts of the world. To attain this purpose, each country resorted to significantly changing the ellipsoid's reference point, Re-Position. In this situation, after making this simple alteration, the ellipsoid is no longer what it was, but it has evolved into something new, which we name a reference (a geodetic datum, a local datum, or any datum, simply). That is, any country's national reference is nothing more than a global ellipsoid whose status has been altered in some way to fit this country and be the closest representation of the shape of the geoid (the true form of the Earth) in this country. It should also be emphasized that the fewer variations there are between a country's local reference and the geoid, the more accurate the maps generated using this reference. The fact that there are numerous local references for various nations, all of which rely on the same global ellipsoid but alter its status in various ways, should also be recognized in this context.

Types of Datum

The references that we have talked about so far are what we can call the "horizontal datum," which are for determining locations in the horizontal plane. When dealing with coordinates in the vertical plane (ie, heights), we need another type of reference, which is the vertical datum. The geoid is the vertical reference used by many countries around the world, therefore finding it requires finding the location where the average marine surface is zero.

Geodetic Coordinate System

the geographic latitude and longitude of a place on the surface of the earth, calculated by geodetic measurement of the distance (mostly using the triangulation method) and the bearing (azimuth) from a number of other sites whose geographic coordinates are known. On the surface of a reference ellipsoid, which represents the form and size of the earth, geodetic coordinates are computed. Due to errors in the measurements of the accepted ellipsoid and deviations from the perpendicular, they deviate slightly from latitude and longitude as determined by astronomical methods. A point's altitude is taken into account in addition to its geodetic coordinates. It is determined from the surface of the chosen reference ellipsoid, and the amount of its geoidal divergence from this ellipsoid determines how high above sea level it is.

A line that is perpendicular to the geoid and goes through any chosen point above the surface of a geoid is created. The following set of geodetic parameters are defined using this line, known as the geodetic local vertical:

Geodetic altitude is the distance from the selected point to the reference geoid, measured along the geodetic local vertical, and is positive for points outside the geoid.

Geodetic latitude is measured in the plane of the local meridian from the true Equator of the Earth to the geodetic local vertical, which is measured positive north from the Equator.

Longitude: measured positive eastward in the plane of the Earth's real Equator from the Greenwich meridian to the local meridian.

The geodetic coordinate system additionally defines the following parameters for reference:

Geocentric latitude is measured in the plane of the local meridian from the Earth's actual Equator to the line connecting the coordinate system's geometric center to the point where the geodetic local vertical intersects the surface of the geoid.

Declination is the angle measured in the plane of the local meridian from the true Equator of the Earth to the center of the coordinate system.

 

Geoid: The Real Shape of the Earth

Until the sixth century BC, when the Greek scientist Pythagoras arrived and claimed that the world was spherical in shape, men considered that the earth was a solid disk that hovered above the surface of the water. The experiment of the Greek scientist Aratustin was the first attempt by scientists to estimate the size or circumference of this sphere. During their voyages in the fifteenth and sixteenth centuries, the explorers Columbus and Magellan supported the earth's sphericity, which is recognized for its rotation around the sun. The famous scientist Newtown created various scientific theories in 1687, the most notable of which was that the balanced form of a homogeneous fluid mass subject to gravity and revolving around its axis is not a completely round sphere, but rather a somewhat flattened shape towards the poles. The French Academy of Sciences conducted two voyages in 1735 to make the necessary measurements to corroborate this concept, and the results confirmed that the Earth is flattened and not perfectly spherical in shape.

Shape of Earth

We live on the planet's surface, and when we want to identify any location on Earth, we must first define this surface - its shape and size - so that we can know exactly where we are. The natural surface of the planet, comprising continents, oceans, mountains, valleys, and seas, as formed by God the Highest, is neither a fluid form nor is it regular enough to be simply articulated. Scientists looked for a less complicated hypothetical form of the Earth and settled on the idea that because the water area in the oceans and seas accounts for roughly 70% of the Earth's area, the shape of the Earth is almost the average shape of the water surface (if we ignore the movement of the water surface due to ocean currents and tides) are the Sea Level, abbreviated as MSL letters, and if we extend this surface under the land to create an integrated shape, this shape will be closer to the true shape of the Earth.

This hypothetical shape was given the name geoid (it should be noted that there is a difference of only 1 meter between both the MSL and the geoid, but in most engineering applications this difference is overlooked and it is considered that both shapes and terms refer to the same body). However, according to Newton's previous principle, the shape of this geoid will not be regular because the geoid's surface is perpendicular to the direction of the earth's gravitational force and is subject to the centrifugal force caused by the earth's rotation on its axis, and both forces differ from one place to another on the earth's surface due to the non-uniform distribution of density. As a result, it was determined that the geoid represents the actual shape of the Earth, but it is also a complex form that is difficult to represent using mathematical equations that allow us to construct maps and establish positions on it.

Geoid vs Ellipsoid

Due to the complexity of the geoid and the difficulty of representing it with mathematical equations, scientists tended to search for the closest known geometric shapes and found that the Ellipse is the closest. If this Ellipse rotates around its axis, it will produce an Ellipsoid or Ellipsoid of Revolution, also known as the Spheroid (the name ellipsoid is the most common). Perhaps they will now come to mind with a question: What is the difference between the ellipse and the circle? Or, in other words, what is the difference between the ellipsoid and the ball? In contrast to the sphere, which is totally spherical, the ellipsoid is somewhat flattened at both poles. Furthermore, the sphere has a diameter that is the same in all directions, whereas the ellipsoid has two distinct axes. To express an ellipse, two elements must be defined (a sphere is represented by only one element, its radius):

•    Half of the major axis (the axis in the plane of the equator) is denoted by the symbol a.
•    Half of the minor axis (the axis between both poles) is denoted by b.

Some express the ellipsoid in another way through the two elements:

•    Half of the major axis (the axis in the plane of the equator) is denoted by the symbol a.
•    The coefficient of flattening is denoted by the symbol f and is calculated from the equation:

f = (a – b) / a or f = 1- (b / a)

Several characteristics distinguish the ellipsoid shape, including:

1- The simplicity with which calculations can be performed on its surface (as it is a well-known geometric shape).

2- The surface of the mathematical ellipsoid and the surface of the geoid are not significantly different (the maximum difference between the two is only 100 meters, which represents the largest geoid height). It is worth noting that the distance between the geoid and the sphere is around 21 kilometers.

Geoid Applications

The geoid is used in the following applications:

1- In Earth satellite remote sensing and geoprocessing data processing, local reference surfaces, such as the normal surface, are determined.

2- In cadastral surveying, the surface of the ground being surveyed is determined (also called a reference surface).

3- In land surveying, to locate high-precision GPS receivers, as well as for other high-precision positioning applications such as 3D mapping and KML processing.

4- To examine Earth surface changes, such as tectonics, landslides, erosion, and so on, in geology and geomorphology.

5- In oceanography to determine local sea level, e.g., tidal datum (not applicable for surveying).

6- In navigation to determine a ship’s position using a satellite system.

7- To determine the mean sea level over the entire Earth in hydrography (not applicable for surveying).

 

GIS Data Types and Methods of Analysis

 In general, data can be divided into two basic types: spatial data and non-spatial data. Spatial data determine the geographical location (coordinates) of the phenomenon or spatial feature under study on the Earth's surface. Non-spatial data is any data that is not related to a geographical location but is related to the same spatial feature. Some refer to non-spatial data as metadata (Attribute Data), but this term may not be accurate or comprehensive in describing the quality and characteristics of this type of data. When we talk about a specific school, for example, the geographical coordinates that express the location of this school on the earth's surface are its spatial data, whereas the non-spatial data for these teachers include their names, numbers, classes, classes, and students.... etc.

Data Analysis in the Framework of Geographic Information Systems

There are two types of data analysis within the GIS framework. While spatial data is referred to as "spatial data analysis," statistical analysis also includes the interpretation of non-spatial numerical data. A statistical examination of the number of classes and pupils in this institution can be used to determine the average intensity of one classroom. On the other hand, the spatial analysis of the schools in one of the city’s neighborhoods will provide us with a description of the nature of the distribution of these schools according to the urban area and will answer the question of whether this distribution is regular and homogeneous in this neighborhood or does it make a difference to the locations of these areas.  It is also possible that the spatial analysis will identify the best geographical locations for the establishment of these new schools.

To build a spatial model of spatial phenomena, the spatial analysis assumes that each phenomenon has a space or spatial scope and a certain spread and distribution (i.e., a pattern of distribution).

Spatial analysis can be performed at different levels: two-dimensional, three-dimensional, and four-dimensional.  Only horizontal locations (longitude and latitude, for example) that express the geographical location of the elements of the phenomenon under study are analyzed in two-dimensional analysis (or 2D). If the values of the third dimension (height) for the phenomenon's elements are available, it is possible to analyze the data in three dimensions, or what is known as Surface Analysis, for example, it is possible to represent the model of the study area and show the difference in its topography between its different Sections and the creation of vertical sections in the area. Also, it is possible to perform spatio-temporal analysis (4D) if the same data is available for several time periods.

Types of Spatial Data

Data in GIS is represented by two models: (1) linear or directional data (Vector Data) and (2) network or cellular data (Raster Data). A realistic representation of the world can be achieved by combining raster and vector data types.

Vector Data

The vector data type stores data as points, lines, and polygons. In comparison to the raster format, less computer memory is used, and position accuracy is improved. Vector data can be used to store data with discrete spatial boundaries, such as country borders, land parcels, and streets. The vector data type records and displays object coordinates with complete measurement accuracy in comparison to ground measurements. In comparison to the raster data type, the vector data type contains less information for the same area. Furthermore, alphanumeric attributes can be easily applied to the defined schemes that express physical objects with points, lines, or polygons. The calculation of vector positions and intersections adheres to analytic geometry principles.

Raster Data

Data in the raster data type are represented by pixels with values, forming a grid, allowing certain operations that were not possible with the vector data type. Map Algebra is used to create index maps using the raster data type and multiple data layers. Raster data is useful for storing data that changes continuously, such as aerial photographs, satellite images, chemical concentration surfaces, and/or elevation surfaces. Raster data is made up of a two-dimensional (2D) grid of cells (pixels). The grid is distinguished by its georeferenced origin, georeferenced orientation, and raster cell size (pixel size). Raster data can be arranged in three dimensions as well. In this case, the three-dimensional (3D) cell is transformed into a cube (a voxel). The pixel resolution limits the geometric accuracy of raster data. Aside from geometric correction procedures, radiometric transformations can be applied to raster data. Furthermore, Boolean algebra operators can be used to combine data from different raster layers.

 

 

GIS Definition and Overview

A geographic information system (GIS) is an integrated system that is used to produce, capture, store, analyze, manage, and visualize all forms of spatial or geographical data and information. Such systems are regarded as critical instruments, among others, in the scientific subject of geoinformatics. GIS employs core principles of geography, cartography, and geodesy to enable end users to generate queries, analyze spatial data, offer data in maps, and exhibit the ultimate outcomes of all of these activities via detailed thematic digital maps.

What is GIS Used for?

Spatial data and information can be retrieved and integrated using such systems, and automated applications (static or dynamic) can be created to cover a wide range of fields of interest, including engineering, planning, management, transportation/logistics, insurance, telecommunications, and the environment. Many GIS applications have been created, but are not limited to, the following sectors:

·        Atmospheric sciences

·        Agriculture and forestry

·        Archaeology

·        Construction

·        Commerce

·        Defense

·        Environmental protection/natural disaster management

·        Governmental Administration

·        Geophysical research

·        Health/medical resource management

·        Transportation

·        Telecommunications

Although the majority of GIS applications use shared starting datasets, an administrative authority can produce its own spatial data and metadata for its own GIS if appropriate. The majority of users are only interested in examining features of GIS data. Significantly fewer groups of users are active in spatial data analysis and/or the production and update of initial/thematic/attribute data.

Components of GIS

The data overlay is a structural feature of GIS. Analytically, each type of data represents a different data layer. Many various layers of data can be evaluated and merged using GIS, resulting in final data and deliverables. The integration of diverse data layers enables the creation of final thematic digital maps that respond to user needs. All that is required for the combination of several data layers are some common properties, features, and the use of the same datum and projection system across all layers. A GIS, as an integrated system, is made up of five major components:

·        Hardware (computers, servers, digitizers, scanners, and printers)

·        Software (operating system, GIS application)

·        Users (basic users with varying levels of access who provide services, analyze data, coordinate procedures, and define final products, as well as end users who view/obtain final data and products)

·        Data types that are supported (any kind of spatial data of vector and raster types, as well as attribute data)

·        Procedures (e.g., input/capture data, data management, spatial analysis and modeling).

Geographical Information Systems are Science or Technology

Many people disagree on whether GIS is a science or merely a technology. Some believe that it is a discipline that overlaps with various other sciences like as surveying, computing, statistics, and geography. Each key that is pressed in any geographic information system application is nothing more than the execution of a series of processes that can be traced back to one of the aforementioned sciences. For example, within the GIS program, the command "Change the projection" is based on the implementation of a set of mathematical spatial equations (the geodesic area) that define the steps for calculating the projection map change from one type to another, as well as co-ordinates for other references.  Accordingly, geographic information systems constitute, from the point of view of those who develop them and invent new tools within them, a knowledge of computer and information sciences. On the other hand, whoever uses GIS programs, as they are, in his field of specialization sees them as a new technology that helps him in practical applications in his field of work; these are the users of GIS.

The overview of the application of geographic information systems is that they provide their users with answers to five questions that discuss each of the following: location, condition, trend, pattern, and model:

·        Location: What is in a specific location? GIS responds by displaying data (map and metadata) about the phenomena in a specific place.

·        Condition: Where is this requirement located? GIS answers by identifying locations that meet certain conditions or specifications.

·        Trend: What has changed? GIS provides an answer by specifying the state of a particular site on different dates in order to know about the variables occurring there.

·        Pattern: How are the phenomena distributed spatially? GIS answers by determining the distribution pattern of a particular phenomenon in a specific geographic spot.

·        Model: What if? GIS provides an answer by formulating a natural phenomenon and understanding its dates and places of occurrence so that changes that may occur in it can be predicted.

Importance of GIS

GIS technology is to geographical analysis what the microscope, the telescope, and computers have been to other sciences. It could therefore be the catalyst needed to dissolve the regional systematic and human physical dichotomies that have long plagued geography and other disciplines that use spatial information.

GIS is a system that integrates spatial and other types of information into a single system and provides a consistent framework for interpreting geographical data.  GIS allows us to modify and present geographical knowledge in new and fascinating ways by digitizing maps and other types of spatial information.

GIS makes connections between activities based on geographic proximity. Looking at data spatially can frequently lead to fresh insights and answers. These connections are frequently overlooked in the absence of GIS, but they are critical to understanding and managing activities and resources. For example, we can use geographic proximity to link toxic waste records with school locations.

GIS provides spatial access to administrative documents such as property ownership, tax files, utility wires and pipes.

Novation Agreement 

Novation is the transfer of contractual rights and responsibilities from one party to another. While the benefits of a contract can be transmitted by assignment, the parties must use a novation agreement to transfer both the benefits and the liabilities.

A novation happens when one contract is canceled and replaced with a new contract in which the original contractual duties are carried out by different parties. In the context of building design and construction, novation typically refers to the process through which design consultants are first engaged to the employer  but later 'novated' to the contractor.

This is common on design and build projects where the design team is appointed by an employer to conduct preliminary studies or prepare a concept or detailed design, but when a contractor is appointed to carry out or complete the design and construct the works, the design team (or a part of the design team) is novated to work for them.

This can be advantageous to employer s because it preserves continuity between pre-tender and post-tender design while leaving the contractor solely responsible for designing and building the project.

The procedure of novation does not hold a contractor liable for any design work done for the employer prior to novating their contract. To accomplish this, the building contract must clearly declare that the contractor studied and adopted the design.

Documentation of the Novation Agreement

Without approval, a novation agreement is not feasible. If novation and the terms of the novation agreement were not agreed upon when the consultant was first hired, they are under no duty to consent to be novated. It is also critical that the primary contracts between the employer and the consultants, as well as the primary contracts between the employer and the contractors, have specific language requiring the contractor and the consultant to enter into the novation agreement.

To eliminate the risk of simply agreeing to an unenforceable agreement, a specimen form of the proposed novation agreement should be affixed to the original contractual instrument.

It is critical that any novation documentation is properly drawn up and makes clear which services consultants performed for the employer and which they will now perform for the contractor; otherwise, initial appointment agreements, such as a requirement for the consultant to inspect the contractor's work and report to the employer, may be rendered meaningless when they are in fact now appointed by the contractor.

Kinds of Novation

Standard: When two parties agree that additional conditions must be added to their contract, creating a new one.

Expromissio: This novation must involve three parties: a transferor, a counterparty, and a transferee. All three parties must agree to the new terms and enter into a new contract.

Delegation: One of the contract's parties transfers their responsibilities to a new party, legally tying that party to the contract's provisions.

Novation vs. Assignment

An assignment transfers rights or property from one person or business to another. However, the assignment merely transfers the benefits; any duties stay with the original contract party. The new party receives benefits and potential liabilities due to the novation.

Another significant difference is that novation requires the approval of all parties involved, which is why novation is nearly often accomplished through a tripartite agreement. Subject to the precise provisions of the contract, it is not necessarily essential to get consent in the case of an assignment.

Novation Subcontractor of Construction Contract

A novation agreement transfers a construction subcontractor's rights and duties from the first (in administration) contractor to a second (solvent) contractor.

Changing a consultant's appointment from the professional consultant and the employer to the professional consultant and the contractor under a novation agreement. A deed of novation is typically used on a construction project to transfer the appointment of a professional consultant from the employer and the professional consultant to the design and build contractor and the experienced consultant.

Novation Agreement Consideration

Most common Design-Build contracts allow for novation and include standard novation deeds. The following issues should be taken into account and handled by parties to a novation deed:

Release

The standard novation deed includes a general release in which the outgoing and continuing parties release each other from all claims arising from the original contract.  Parties should obtain clarification on the novation's impact on accrued rights, claims, and demands arising from the original contract, as well as all future rights, claims, and demands.

Warranty

The requirements of the standard deed of novation include a warranty by both the outgoing and continuing parties that the work completed by the continuing party under the original contract is in conformity with the provisions of the original contract.

Risk management

The crucial point is that the insurance program for the consultant must be properly structured to meet this potential gap.

Advantages and Disadvantages of Novation in Construction

Advantages of Novation are:

A Reduced Learning Curve: Working with the customer early on allows the architect to obtain a thorough understanding of the customer's needs. If the architect is not novated, this knowledge may be lost, and parts of the process may have to be repeated with a new design team. This can be damaging to the ultimate design of a complex or highly technical undertaking. Novation can give some economies of scale that the customer can benefit from in terms of the design team's learning curve. If the architect knows they will be involved throughout the process, not just during the pre-contract and tender stages, there is a chance of achieving a lower overall cost. Not to mention the time and money it takes to brief a new design team.

Reduced Contractual Risk for the Employer: The procedure of novation and the transfer of responsibility to the contractor implies that the employer contractually accepts minimal risk while yet having control over project design. Of course, exact contracts vary, but at the point of novation, the Design-Build contractor is responsible for all future design work, which can occasionally extend to cover all previous design work accomplished prior to the contract being granted (including any design errors). As the contract proceeds, the employer only has to deal with one company: the contractor. This streamlined method benefits the employer by removing the possible complications and hassles of interacting with many organizations to resolve issues.

Early design development improves cost certainty: Cost certainty is better in Design-Build projects when the initial employer's needs are most precise. Novation assists customers in achieving a well-developed design early in the process by providing the architect with clarity across the duration of their collaboration. If the architect is satisfied that the scheme will move forward and is not working "at risk," they are more inclined to develop the design further, providing for a more accurate grasp of costs during the tender stage and boosting total cost certainty.

The Contractor has more influence and control over the design: Traditional contracts have the potential for conflict between the contractor and the design team over who is responsible for flaws and whether they are the consequence of a design or construction quality issue. This often puts the employer in a tough position and raises the likelihood of the parties reaching a 'stalemate. 'Novation helps to avoid this problem; in an integrated design and construction team, the contractor is automatically responsible for resolving the issue. These concerns should potentially appear less frequently in a novated Design- Build contract because the designer and contractor worked closely to jointly develop and agree on the final design, as well as to ensure buildability and quality. Through the influence of design decisions at each level, the contractor is better positioned to manage and control the risk to quality.

Whereas The Disadvantages of Novation are:

The Contractor and Architect Must Have a Good Relationship: On every Design- Build project, the contractor and architect must collaborate closely, but this is more crucial when novation has occurred. Novation is frequently criticized for putting further strain on these parties' relationship. Without a healthy relationship, there is a larger possibility that the project will suffer and crucial concerns such as time and cost will suffer.

 

 

Bridging Method for Construction Project Delivery

What is Bridging in Construction

The Bridging method is a tried and true method for completing construction projects. Bridging is more effective than other methods in protecting the project owner's interests. In a design-build contract, the bridging method places final design and construction responsibility on the contractor. However, unlike a typical design-build contract, the owner is fully protected from the start with all aspects of the design and specifications that are important to the owner, and the owner ends up having an agreement with the contractor to have full design-build responsibility.  All aspects of the design and specifications that are important to the owner are fully protected by the Owner's Design Consultant ("Bridging Architect"), while proposing design-build contractors are free to use their skills and capabilities to provide the owner with the best total price and time of completion proposals.

A properly executed Bridging project's construction price is not only as dependable for the Owner as a price based on final Contract Documents under the traditional Design-Bid-Build method, but it is even more dependable because the Owner's exposure to contractor-initiated change orders due to errors or omissions in the contract documents is greatly reduced. Frequently, change orders result in considerable increases in the ultimate building contract price. Bridging should be considered for every construction project as a cost-effective and efficient form of project delivery that, when done correctly, would save the owner time and money.

Two design firms are involved in the bridging process. The first is under contract with the owner, and its duties extend halfway through the design process. The resulting documents define the aspects of the project that the owner wishes to control; they also provide enough detail to allow the selection of a construction company. The documents allow the contractor to seek alternative construction methods and thus achieve cost savings in construction technology. Following the selection of the contractor, the contractor appoints a second design firm (with approval by the owner). This design firm is hired as a subcontractor by the contractor and is in charge of final construction drawings and specifications. Construction does not start until the construction drawings are completed and all parties agree that the owner's intentions will be carried out.

Advantages

Bridging typically saves money on contract prices and provides the owner with a fixed construction price in about half the time and at half the cost of traditional design. Bridging also significantly reduces:

•        Costs incurred as a result of a change order initiated by the contractor.
•         Claims made against the owner
•         Delays/costs/disputes associated with resolving the ever-present post-construction "bugs."

Bridging also speeds up and smooths out construction, and project acceleration processes work well with it.  All of these advantages for the project owner, on the other hand, can be obtained using Bridging without sacrificing:

•         Possibility to be creative.
•         Control of design.
•         Control over design specifics.
•         Engineering quality.
•         Construction quality

The Bridging Method in Action

Schematic Design: After the program of requirements and budget have been established, and the site has been located, the Owner hires a Design Criteria Consultant (DCC) to complete the schematic design. There will be consultation between the DCC and the engineers. At this stage of the design process, however, few engineering drawings will be included in the DCC's drawings.

Design Development + RFP: The DCC is in charge of preparing the bridging contract agreements, which serve as the foundation for the Owner-Design-Builder agreement. This necessitates a DCC effort at least as comprehensive as an architect's usual design development services; yet, the finished documents will be vastly different because far more architectural design will be done. A combination of performance and design specifications will be prepared by the DCC and its consultant engineers. The bridging contract materials, which also serve as the Request for Proposal, are made up of the DCC's designs and specifications as well as other legal documents. To safeguard the Owner, the design, and the quality of the construction, everything should be thoroughly developed and/or specified by the DCC and incorporated into the DCC's design documentation.

Bid/Negotiation Phase: The Design-Builder submits definite bids, or a firm pricing is negotiated with a chosen Design-Builder. As a Subcontractor, the Design-Builder will use an approved, distinct design professional, or the Design-Builder may be a design-build company. Once satisfactory prices have been received, the Design Builder's design professional is given notice to proceed with the preparation of final comprehensive Construction Documents.

Construction Documents: The DCC oversees the creation of Construction Documents, which are prepared by the design Design-Builder's professional. These are the documents that are commonly referred to as building documents. The DCC examines these documents and reports to the Owner, who handles any concerns that arise as a result of the examination. The DCC, on the other hand, does not authorize these documents. The Contract Documents will be supplemented but not replaced by the Construction Documents prepared by the Design Builder's design professional. If a discrepancy is uncovered later, the Contract Documents will take precedence over the Construction Documents.

Second Step Award: From the standpoint of the Owner, one option to explore is to give the Owner the opportunity to terminate the contract for convenience at the end of the Construction Documents Phase by paying a previously agreed-upon fee for the Construction Documents (with the Owner then owning the documents). This is a crucial safeguard since it preserves the Owner's leverage at this point. It also necessitates the Design-Builder and the design-Design-Builder's expert adhering to contract restrictions.

Construction Phase: The Owner manages the design-build contract, with the DCC or other independent inspectors or testing firms witnessing and reporting on the work in progress. The Design-Builder's design professional inspects shop drawings and files them with the Owner on a regular basis. The DCC's reports to the Owner result in progress payments to the Contractor and retained funds.

Bridging Design-Bid-Build Delivery Method

The procedure of bridging with Design-Bid-Build is well-known in the industry and is logical and well-organized. Before allowing construction to begin, the owner receives a firm price based on all contract documents. The Owner has a direct professional relationship with the Architect and Engineer. Obtaining a sufficiently reliable total price, on the other hand, takes too long and costs the Owner too much. The strategy assumes that architects and engineers have the most knowledge of construction processes and costs, which is not always the case. Assumes that the Contract Documents (final drawings and specifications) are error-free, which is unattainable.

Bridging  Design-Build Delivery Method

The design-build bridging construction method is a two-step process that differs significantly from design-build in two ways. First, the owner hires a separate architect or engineer to set approximately (30-50)% of the project's "design criteria." After receiving proposals from design-build firms based on the design criteria package, the owner hires a design-builder to complete the design and construction. The design criteria package serves as a "bridge" document between the initial project concept and the design-build phase, as the name implies. These bridging documents include enough preliminary drawings and specifications to allow design-build bidders to submit a quick to react bid.

The second distinction between design-build bridging and design-build is in the fee solicitation and contract award criteria. Fees for design-build services are not solicited in the RFQ, and the contract is awarded based on the qualifications-based selection method under the design-build method. Fees and price estimates are solicited in the RFP for design-build services under the design-build bridging technique, and the contract for these services is granted based on the lowest responsive, responsible bidder standard of award.

Bridging  CM-at-Risk Delivery Method

The Contractor CM-at-Risk enters the process early in order to offer costing, timing, and construction method information to the Owner's Architect and Engineers while the design is still being finalized. The contractor is paid a fee and secures subcontractor pricing that are competitive. At one or more phases during the design process, the contractor delivers a "Guaranteed Maximum Price" (GMP). But a GMP based on less than 100 percent full drawings and specifications is not contractually enforceable and can be deceptive to the Owner, just as it is in Design-Build. In many circumstances, a conflict might arise as a result of the CM-at-Risk using the same subs on other projects while also acting as a typical general contractor on other projects. The "finger pointing" problem that plagues Design-Bid-Build is also present with CM-at-Risk.

There is no conflict of interest if the Owner's Design Consultant and an external project Manager are the same firm because the Owner's Design Consultant is not the Architect/Engineer of Record. As a result, the responsibilities of Owner's Design Consultant and project Manager can be played in a variety of ways:

•               Separate Owner's Design Consultant and External Project Manager
•     Owner's Design Consultant in collaboration with Owner's Internal Project Manager
•         The same firm serves as both the external project manager and the owner's design consultant.

Conclusion

The bridging method has detractors because it has the potential to limit the design-build team's inventiveness. Bridging, on the other hand, aids the conventional Owner's transition to the design-build project delivery system by offering an "independent" design criteria consultant and a comfortable scope definition level. As the Owner develops expertise dealing with the dynamics of the design-build process, this strategy may lead to full use of the design-build project delivery system.