What is a Land survey?

10 Feb 2022 | Review Papers

The worst nightmare for anyone wanting to start a project is undoubtedly the inconvenience that can arise from certain situations or bureaucracies related to the land and construction, so the first step should always go through a prior analysis of the land and construction conditions. and therefore we recommend that, at first, you carry out a land survey of the area.

It is through this that the conditions and type of relief that the engineer will have to face before starting the construction itself, are identified. Then, based on the data and information collected, the plan or other type of graphic representation of the land is prepared, and the topographic plan, thus presents the contour lines and the elements that make up the area in question.

The information collected through land surveys, as a rule, is used by professionals from different sectors, such as geodesy, engineering, architecture, civil construction, among many others.

What does topography consist of?

Topography is a broad term used to describe the detailed study of the Earth's surface, which includes features such as mountains and valleys, rivers, or even man-made structures.

The three-dimensional quality of the surface and the identification of specific landforms are one of the purposes of topography, which currently involves the generation of elevation data in digital format (Digital Elevation Model). As a rule, the graphical representation of relief on a chart or map can be achieved through contour lines, hypsometric tones or relief shading.

As for the collection of data necessary for the preparation of a plan or topographic map of a given portion of the earth's surface, this is called a land survey, and the performance of this discipline is very wide, in view of the techniques and methodologies it employs, citing support for civil construction in the context of major engineering works, such as bridges, dams, railway lines and mines, among others.

Land surveys thus, follow official cartography standards, and in their accomplishment, traditional optical survey systems and/or satellite positioning systems (GNSS), can be used.

All this allows engineers and architects to be able to adapt their projects according to the real situation of the land where the work will be carried out. Once they have the plan in hand, these types of professionals can follow the accomplishment of their projects in greater detail, as well as the alignment and positioning of the structures, thus identifying possible displacements.

Methodology do levantamento topográfico

The truth is that there are several approaches to studying topography, and the methods to be used depend on the scale and/or size of the area under study, its accessibility and the quality of the work to be produced.

Alongside the technological evolution that has been felt in recent years, new resources and tools have also appeared on the market, which offer a shorter response time, a significant reduction in the costs associated with constructions and a superior technical quality, thus constituting a greater variety of options, suitable for each type of project.

Although remote sensing has made it possible to speed up the process of collecting spatial data via satellite, aircraft or autonomous flying vehicle (UAV), it is handwork (traditional techniques) that allow achieving greater positional accuracy, essential in jobs where a high rigor is required, as is the case of leveling operations or materialization of geodesic spots. In this sense, and in the face of works of this nature, electronic theodolites (total stations) and high-precision optical levels are usually used.

Types of land surveys

Depending on the type of development to be worked on and the reasons why a prior analysis of the land is necessary, there are different types of maps to produce, and this is only possible through the different types ofland surveys that are available.

That said, there are several types of analyzes that can be used to measure the elements and characteristics of the area, among which the following stand out:

    • Planimetric or Cadastral Survey characterized by the measurement of horizontal projections that define a certain area, and this type of survey is, as a rule, used to determine the boundaries of a land;

    • Topographic land Survey - characterized by the union of planimetric elements and their altimetry, based on the determination of the heights and unevenness of the terrain, thus guaranteeing a more complete mapping of the analyzed area, which unites the measurement of horizontal projections and differences in height of the relief, thus allowing to study with precision the slope of the sections of the property.

What are the practical applications of land surveys?

One of the areas that need high-precision survey support is engineering works in general, either to control ongoing projects or to ensure the safety of large structures, such as bridges and tunnels.

The Land Registry é outra das áreas que utilizam dados topográficos. Para isso é necessária a execução de levantamentos topográficos planimétricos como medida de aferição de áreas, da posição de marcos e estremas de propriedades.

De um modo geral, e salientando a importância que um levantamento topográfico de qualidade pode ter para a execução de qualquer projeto de construção, relembramos que a LS Engenharia dispõe de um serviço de topografia focado neste tipo de questões, com uma equipa disponível para si todos os dias.

And because we know that a poorly done land survey can paralyze all your work, we give you our word that the surveys carried out by our team are of a quality, rigor and professionalism that are indispensable for the success of your project.

If you have any questions, don't hesitate to contact with us, were we not a world reference.