What is Reconnaissance Survey in Civil Engineering?
What is Reconnaissance Survey in Civil Engineering?
What is Reconnaissance Survey in Civil Engineering?
A reconnaissance survey is the preliminary survey of a site to determine its feasibility for a proposed civil engineering project.
The reconnaissance survey is typically conducted by a civil engineer or surveyor and includes topographic surveys, site inspections, and preliminary estimates of the project costs.
The reconnaissance survey helps to determine if a proposed project is feasible and if it is worth further investment.
The purpose of reconnaissance surveying is to identify potential problems and areas of interest that may need further study.
Reconnaissance surveys are often conducted before construction or development projects to help identify potential hazards and inform the design of the project.
Reconnaissance surveys are a sort of field survey that is frequently used to collect preliminary information about the presence or absence of historic properties within a project area.
In general, reconnaissance surveys entail limited shovel testing in regions suspected to hold archaeological treasures.
Reconnaissance Survey could alternatively be characterized as an exhaustive investigation of a whole area that could be used for a road or an airstrip. Its goal is to eliminate routes or sites that are impracticable or unworkable and to discover more potential routes or sites.
Reconnaissance Survey Design
- During the reconnaissance survey, design and military qualities should be taken into account. Keep in mind that future operations may necessitate a larger road network.
- A thorough examination of the route plans and specifications is required. If these are not available, the following might be used as a guide.
- Whenever possible, route portions of the new road along or over existing roads, railroads, or trails.
- Keep drainage structures to a minimum by locating the route along ridges and streamlines. When following a stream, keep the slope well above the high water line.
- Choose a path that is as close to the source of material as possible, and build the road along contour lines to eliminate extra earthwork.
- Choose a path that is as close to the source of material as possible, and build the road along contour lines to eliminate extra earthwork.
- Locate the road on the sunny side of hills and canyons, and on the canyon wall where the strata’s inclination tends to maintain the road rather than cause it to slip into the canyon.
- Place roads in advanced battle zones such that they are hidden and safe from enemy fire. This may occasionally clash with engineering considerations.
- Choose places that conserve engineer assets by avoiding rock work and over-clearing.
- Avoid sharp curves and places that require bridging.
Reconnaissance Survey Methods
The reconnaissance survey methods might be carried out in the following order:
- Examine topographical survey sheets, agricultural, soil, geological, and meteorological maps, as well as aerial photos.
- Aerial photographs wherever possible and necessary.
- Ground reconnaissance, which may include another round of aerial reconnaissance for inaccessible or difficult areas as needed.
- Ground Reconnaissance Survey
Study of Survey Sheets and Maps
A reconnaissance survey begins with a thorough examination of all available maps. Following a study of the topographical features on the maps, a number of economically feasible general alignments are chosen while keeping the following factors in mind:
- Alignment that takes into account all control points and is shorter and more affordable while meeting gradient and curvature requirements.
- The alignment’s shape.
- Avoiding marshy ground, steep terrains, unstable hill features, and locations prone to extreme climatic conditions, flooding, and inundation as much as feasible.
- The requirement to connect key villages and towns.
- Problem-solving.
- The need to conserve the ecosystem and keep ecological balance.
If aerial images are obtained, they should be taken at a scale of 1:20000 to 1:50000 to enhance the information provided by topographic maps.
Aerial images, when stereoscopic techniques are used, can offer quantitative data as well as substantial soil and subsoil information if evaluated by a professional photo interpreter.
Aerial Reconnaissance Survey
Aerial reconnaissance will provide a bird’s-eye view of the alignments under consideration as well as the surrounding environment.
It will assist in identifying issues that need the rejection or modification of any of the alignments.
The airborne survey could be used to make a final choice regarding which alignments should be explored in depth on the ground.
Ground Reconnaissance Survey
Ground reconnaissance entails a general investigation of the ground by walking or riding along potential routes and gathering all relevant information for evaluation.
In the event of hill sections, it may be advisable to begin the reconnaissance from a mandatory position near the top.
If a location is inaccessible for ground reconnaissance, an aerial method should be employed to clear any doubts.
It is best to leave reference pegs while reconnoitering on the ground to assist future survey operations.
Compass, Abney level / alti-meter, pedometer, aneroid barometer, clinometers, ghat tracer, and other instruments are commonly used for ground reconnaissance.
Communication is aided with walkie-talkie sets, which are especially beneficial in challenging terrain.
The use of the above-mentioned tools to get ground slopes, maximum gradients, height of crucial summits or stream crossings, and position of mandatory points acts as a check on the maps being utilized.
Reconnaissance Survey Reports
A report should be created based on the information gathered during the reconnaissance survey.
The report should include all essential information gathered during the survey, as well as a plan at a scale of 1:50000 depicting the alternative alignments investigated, along with their general profile and preliminary cost estimate.
It should also outline the advantages and disadvantages of the various possibilities in order to aid in the selection of one or more alignments for extensive surveys and research.
Reconnaissance Survey Purpose
The purpose of the reconnaissance survey is detailed further below.
- The primary goal is to conduct a survey in a specific area about its weather conditions, map, and terrain, among other things.
- It is used to assess the flexibility of alternative highway corridor paths or routes between specific points, and it can take into account the following points:
- It is used to estimate the quantity of earthwork based on
- Topography, geology, and traffic volume,
- Environmental use, and
- Social and economic land use (construction unit cost, agricultural trends, and commercial activities in industries).
- It is used to assess flood records, meteorological data, topography, and other existing services or communications.
- The following are the implications of a reconnaissance survey:
- The results of the reconnaissance survey are used to develop a plan that will aid in the identification and protection of cultural resources.
- It must identify any archaeological sites around the route alignment.
- Investigate the site conditions in relation to infrastructure availability.
Reconnaissance Survey Applications
Some applications are as follows:
Reconnaissance Survey Applications in Civil Engineering
A road survey is the systematic examination of an area to identify the appropriate route and prepare plans and specifications for an improved road system.
A reconnaissance survey is carried out by a party of engineers that maps the route locations, distances, soil classifications, elevations, river flows, communication links (roads and railways), townships, villages, and other settlements were surveyed in detail.
The results are used by the next team of engineers that select a suitable route from previous choices inherited from previous surveys.
Reconnaissance Survey Applications in Geodesy
The purpose of a reconnaissance survey is to provide an accurate idea of the terrain and environment surrounding the proposed survey area.
It is conducted on the basis of a close study of topographic maps and satellite images. The areas are traversed by probing, mowing, and walking, as well as by checking information obtained from aerial photography and ground surveys.
The results of the survey are used in planning for the survey on the ground. They are employed in pre-survey operations and in detailed planning, and they are assessed during surveys.
Reconnaissance Survey Applications in Hydrology
The purpose of a reconnaissance survey is to obtain an accurate idea of the terrain and environment surrounding the proposed hydro-meteorological measurement station. The area is traversed by probing, mowing, and walking, as well as by checking information obtained from aerial photography, topographic maps, and ground surveys.
The results of the survey are used by the next team of hydrologists in planning and carrying out the measurements, which are evaluated during the operations.
Reconnaissance Survey Applications in Architecture
A reconnaissance survey is an inquiry into the condition of a proposed building site to determine if a building can be constructed in accordance with regulations and standards.
It entails a study of maps, aerial photographs, and other available information. A reconnaissance survey report is prepared on the basis of results obtained during the survey.
Reconnaissance Survey Applications in Archeology
The purpose of a reconnaissance survey is to identify any archaeological sites around the proposed alignment, as well as any potential cultural resources (sites, structures, and artifacts).
The areas are traversed by probing, mowing, and walking, as well as by checking information obtained from aerial photography and ground surveys.
This type of survey marks an important step in the process of conducting archaeological investigations.
It serves to confirm or deny hypotheses or constructs; verify or reject evidence; or resolve the extent of disturbance and its location relative to the proposed construction.
Reconnaissance Survey Applications in Business
Reconnaissance survey is an investigation of a market area to ascertain the level of sales potential, competition, and probable profitability. This is undertaken before entering into the market and for this purpose, detailed information about the market condition, behavior patterns of consumers, location of competitors and other such information are collected by means of interviews and questionnaires.
The major objective is to obtain an estimate of sales and profits per unit in order to decide whether it would be commercially viable to enter or continue business in the area surveyed.
Reconnaissance Survey Applications in Environmental Engineering
A reconnaissance survey is a tool used to obtain an idea of the terrain and environment surrounding the area of interest. It is conducted by probing, mowing, and walking, as well as by checking information obtained from aerial photography and ground surveys.
The results of the survey are used by engineers planning the protection system (lines, fences, etc.).
Reconnaissance Survey Applications in Mining
A reconnaissance survey serves several purposes. First, it helps in determining whether or not mineral resources exist in an area. Secondly, it provides a general estimate of ore deposits both for planning purposes and for establishing values for investment decisions.
Reconnaissance Survey Applications in Telecommunication
Telecommunication reconnaissance survey is a technique used to examine a proposed telecommunication system before it is built.
The purpose of the survey is to obtain an idea of existing conditions, potential quality of services such as coverage, reliability, and speed, and the costs involved in obtaining these services from existing systems.
This ensures that there will not be any significant duplication of effort during the early years of operation.
Reconnaissance Survey Advantages
They include:
- It helps in expediting the work since it is completed before any other survey.
- It is reliable since the team already knows the area while they are doing the project, hence they are not likely to make mistakes as they may have to navigate their way through areas they don’t know while doing a survey on the ground.
- It is cost-efficient since the area is already surveyed for roads and therefore no extra time or cost will be spent to carry out surveys.
- It saves time and money by limiting the number of areas that need to be checked for work due to the fact that it has already been done before.
- It allows for a better understanding of the project area by having guidelines already set out, hence minimizing work-related errors.
- It ensures results are accurate and reliable due to various factors such as;
- The maps have been updated.
- Information from topographic maps and aerial photographs has been used.
- The terrain can be surveyed more than once due to the fact that more information regarding the area has been obtained hence ensuring reliability.
Reconnaissance Survey disadvantages
They include:
- Works may not be completed due to the time needed to complete the survey.
- The area may be larger than expected and therefore, more time may be needed to complete all aspects of the project, resulting in costs being more expensive as a result.
- It is less effective than site-specific surveys because areas that have already been surveyed cannot still be used for surveys hence requiring that new areas must be surveyed and recorded.
- Road materials and specifications may already be in place for a project; therefore, it is impossible to follow them and duplicate them but only if the site can be found.
- The results of these surveys are not reliable because regardless of how well the area was previously surveyed on-site, there may still be changes that have occurred that were not included in the original survey.
Reconnaissance Survey FAQs
What is Reconnaissance Survey?
A reconnaissance survey is a way of determining the best route to take while carrying out a project. It involves going around the area and surveying it with the use of aerial photos, maps and other information on hand.
What are the advantages of the Reconnaissance Survey?
This type of survey is considered to be an advantage because it helps to save time and money due to its efficiency. It has also been shown to be reliable.
What are the disadvantages of the Reconnaissance Survey?
This type of survey is not considered to be an advantage as it cannot produce reliable results due to the fact that everything that was done in this survey may have already been changed. It cannot guarantee the accuracy of the information because it was done a long time ago.
What is the importance of a reconnaissance survey?
A reconnaissance survey is a great way of knowing the area you are about to work on. It helps in mapping out the underground resources, land, and vegetation for specific projects.
Also, it helps in knowing what type of approach you need to take to avoid any obstacles that may be found on the way.
How do you carry out a reconnaissance survey?
It involves going out into the field and using your eyes to observe everything there is about the area that will be worked on. Then, depending on what you observe, you will be able to make a decision on the best approach to take.
How do you carry out reconnaissance survey in complex terrain?
The reconnaissance survey is done differently depending on the terrain. In complex terrains, this type of survey is done by taking into consideration all the different factors such as the vegetation and land that are present in that area. This helps to make sure that all the information needed is obtained.
What is the main purpose of site reconnaissance?
Site reconnaissance (a walkover survey): identifying present and possible risks, as well as designing the primary inquiry. The primary inquiry and reporting: Invasive and non-intrusive sampling and testing are used to obtain soil parameters for design and construction.
What are the objects of reconnaissance in engineering surveys?
- Reconnaissance survey: To investigate site conditions and infrastructure availability.
- Preliminary survey: Gathering sufficient data to generate a plan/map of the area to be utilized for planning and design.
- Location survey: To layout work on the ground for actual construction/project implementation.
Why reconnaissance is important to explain tools and various methods used in this?
Reconnaissance (or simply Recon) is the first stage of the Pen Testing procedure. The purpose of recon is to learn as much as possible about the target. The more information there is, the more useful it will be for subsequent phases of pen-testing.
What are the types of reconnaissance?
The four types of reconnaissance are route, zone, area, and reconnaissance in force. Reconnaissance determines geographical characteristics, hostile and friendly obstacles to movement, and the arrangement of enemy forces and civilian population so that the commander can maneuver his forces freely and quickly.
What major points should be included in the project report for a reconnaissance survey?
The reconnaissance survey must cover all potential routes and locations. The reconnaissance survey report should include all of the information gathered, including a description of each route or location, a conclusion on the economics of its use, and, if possible, suitable maps and aerial images.
What is field reconnaissance?
The goal of field reconnaissance is to corroborate the results of the desk study in the field. Additional information pertinent to the project is gathered, and simple index tests on ground conditions are performed.