Settlement monitoring
Soil deformations are divided into natural and anthropogenic (man-made) deformations.
Natural deformations arise from internal processes of the Earth and manifest as movements of the Earth’s crust occurring over centuries, as well as from processes driven by external energy (water, heat), which result in changes in soil conditions. Soil freezing, thawing, moisture variations, and similar phenomena are mostly periodic, follow an annual cycle, and are reversible; however, other natural changes (such as karst and suffosion) are irreversible.
Anthropogenic soil deformations are those caused by human activity, including the construction of underground excavations; pumping of groundwater and other substances contained in the soil; vibrations resulting from blasting works or the operation of machinery and equipment; and deformations caused by changes in natural stress conditions, for example during the excavation of trenches or the construction of structures.
Subsoil deformations, in turn, lead to deformations of buildings and structures, i.e., displacements of a structure or its components in the horizontal and vertical planes. This may result in deterioration of functional performance, reduced durability and service life, cracking, risk of failure, or even collapse.
Large uniform settlements may impair technological performance (for example, the formation of adverse gradients in sewer systems, sinking of door thresholds below ground level, etc.), and long-term uniform settlements may become non-uniform over time.
Non-uniform settlements may cause cracking and pose a risk of structural failure.
Therefore, it is necessary to determine the magnitude of settlements, their non-uniformity, and their variation over time. Often, attention is drawn to the problem only when the situation has already become critical. In practice, there are many cases where the question arises as to whether the observed deformations are dangerous—not only to structures but also to people.
Measurement of settlements and horizontal displacements during both the construction and operation phases makes it possible to determine whether the deformations are normal and progressing in accordance with predictions. Otherwise, the causes must be identified and, in the case of significant increases in displacements, measures must be taken to remedy the situation.
The investigation of the above-mentioned deformations, together with the analysis of measurement results in relation to the engineering geological conditions of the site and the interaction of the structure’s components, is referred to as geotechnical monitoring.
Geotechnical monitoring is a construction investigation service that REIB has been providing to its clients for decades.
Geodetic networks
The establishment of both local and national geodetic networks belongs to the field of higher geodesy. Geodetic equipment and methods intended for high-precision measurements are used to perform work in the field of higher geodesy.
The Estonian national geodetic main network is in good condition and its supplementation and reconstruction are carried out only for specific special needs (for example, when geodetic points are destroyed). Local geodetic main networks are not in such good condition. Despite this, reconstruction of local networks is also carried out mainly only when geodetic points are destroyed.
The multi-level geodetic network being built for the construction of Rail Baltic can also be classified as geodetic main networks. With its number of geodetic points reaching hundreds and probably even thousands, this geodetic network will probably be the biggest challenge for geodetic works in Estonia during the entire construction period of Rail Baltic. A significant part of the Rail Baltic geodetic network will be built by Inseneribüroo REIB OÜ.
In addition to the construction of geodetic main networks, high-precision geodetic measurements are also used in some measurements within the field of engineering geodetic work (for example, subsidence observations, deformation measurements, geodetic monitoring).
As-built surveying
The purpose of as-built surveying is the measurement and documentation of the position and other technical characteristics of completed buildings, structures, or parts thereof.
By its nature, as-built surveying is divided into two categories:
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As-built surveying of a completed object: utility networks (pipelines, cables, etc.), roads, paved areas, and any completed structures. These works are carried out in accordance with the above-mentioned procedure.
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As-built surveying of an object under construction, including its components: earthworks, construction bases, foundation elements, concrete works, load-bearing structures, elevator shafts, etc. These works are not regulated by the above-mentioned procedure.
The output of an as-built survey of a completed object is a drawing provided both on paper and in digital format, which is also submitted to the local municipality. The output format of as-built drawings for objects under construction is agreed upon between the surveyors and the contractor.
Increasingly, modern technologies such as laser scanning and photogrammetry are used in as-built surveying in addition to traditional measurement methods.
As-built surveying of underground utility networks is particularly important. At the time of measurement, the trench of a pipeline or cable must be open at least at junctions and bends. Otherwise, it is not possible to determine the position of the installed pipeline or cable with sufficient accuracy. Inaccurate as-built survey data may be the main cause of damage to pipelines or cables during later excavation works. In addition, as-built surveying determines several other important parameters, such as the gradient of gravity-flow pipelines.
For REIB, as-built surveying is an important field of activity. We have extensive experience and expertise in carrying out this work professionally. Our quality management system enables us to ensure a key requirement for contractors—operational efficiency. Furthermore, our specialists have participated in the development of the above-mentioned procedure, which means we know exactly what requirements a proper as-built drawing must meet.
When accepting an as-built surveying order, it is necessary to know the most suitable time for measurement (the structure completed and the trench still open), the extent of the object to be surveyed, the construction materials used, and whether there are any special requirements not specified in generally applicable regulations.
Ordering as-built drawings is the contractor’s obligation; as-built drawings are part of the construction completion documentation.
Setting-out works
Setting-out works are primarily a service for the contractor, who needs to know the exact location of the structures and other elements to be constructed. Setting-out becomes increasingly complex as buildings grow larger and more complicated. Many setting-out tasks must be carried out with an accuracy of 1–2 mm. Achieving this level of precision requires accurate and calibrated geodetic instruments, as well as well-trained, meticulous surveyors with construction surveying experience who know which methods and instruments are needed to achieve the required accuracy. It must always be understood that no measurement is absolutely exact—there is always some error, regardless of the performer. The key issue is the acceptable magnitude of that error.
The most important prerequisite for carrying out setting-out works is the availability of correct, valid, and today increasingly also digitally accessible design drawings and/or models. In practice, numerous problems arise where the design does not allow precise setting-out due to inaccurate dimensions or incorrect reference schemes. Occasionally, an outdated version of the design is provided to the surveyor. These problems can be significantly reduced by applying BIM technology in the design process.
To ensure the accuracy and effectiveness of setting-out works, the following are beneficial:
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Preparation of the construction site for setting-out works. It is pointless to carry out precise setting-out in dense vegetation or before excavating the foundation pit. For axis setting-out, a high-quality and durable reference framework must be installed in advance.
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Communication between the contractor and the surveyor, so that the contractor clearly understands which points are indicated by the installed markers.
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Consideration of setting-out works by other personnel on site, ensuring that markers are not driven over by machinery and that no hazardous or vibration-inducing works are carried out during setting-out.
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Use of a single surveying company on one site, to avoid discrepancies between reference points established by different surveyors.
REIB provides everything within our control, and everything that modern measurement technology makes possible, to ensure that your construction works proceed accurately and without disruption.
Cadastral surveying
To establish land ownership, a cadastral unit must be formed. There is often also a need to subdivide or amalgamate existing cadastral units, to modify boundaries between units, as well as to restore destroyed boundary markers and to identify boundary locations on the ground. All of these works are carried out by a qualified surveyor holding a licensed land surveyor / land management licence.
Engineering Bureau REIB carries out all works related to cadastral units and their boundaries.
Cadastral surveying is initiated in the Minu kataster environment. This can be done either by the landowner themselves or by a surveyor chosen by the landowner. If the client has no prior experience, it is recommended to contact a surveyor immediately.
If the landowner has initiated the process themselves, they must select a surveyor after receiving the required approvals.
The surveyor carries out the cadastral surveying in accordance with the cadastral surveying conditions issued by the Land Cadastre. To the necessary extent, existing boundary points are measured, the locations of new boundaries are determined and marked with boundary markers, and destroyed boundary markers are restored if required. Boundaries are coordinated with neighbouring landowners. A boundary protocol is prepared.
Finally, the Land Cadastre sends the registration application to the landowner for signature.
After the landowner has signed the registration application, the Land Cadastre forwards the data for entry in the Land Register.
Key regulations related to the field:
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Land Management Act
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Land Cadastre Act
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Procedure for Carrying Out and Controlling Cadastral Surveying
For pricing information and orders, please contact:
Ülle Tammo, tel. +372 733 7150, ylle(at)reib.ee
Topographic surveys
A building cannot be designed on a “blank sheet.” Topographic surveys are an indispensable prerequisite for the preparation of a construction design or a spatial plan.
This work is known by many informal names in everyday language, such as topogeodesy, topo, geo base, base plan, topo base, digital base, or geo survey. None of these terms is terminologically correct; however, in the context of design, they all refer to topographic survey works carried out by surveyors prior to the design and planning of structures.
The output of a topographic survey is a survey report together with a digital site plan, which the designer or planner uses as the basis for their work. In addition to surveying the area, the survey also collects other data required for design purposes—primarily information on underground utility networks, as well as other features present on the site.
The geodetic base plan must not be confused with a cadastral (plot) plan. A geodetic base plan, as it includes utility networks and elevations of the ground surface and other elements, is significantly more accurate and detailed than a cadastral plan. Furthermore, the geodetic base plan must be sufficiently up to date (outdated plans may lack a great deal of essential information), digitally available in DWG or DGN formats, and compliant with the requirements of the Procedure for Carrying Out Construction Geodetic Surveys. In most cases, geodetic base plans are prepared at a scale of 1:500.
Local authorities also monitor the existence and reliability of the geodetic base plan. The absence of proper topographic surveys may cause difficulties in obtaining project approvals from these authorities.
At REIB, topographic surveys are one of our core services. We have extensive experience and expertise in performing this work professionally. Our specialists have participated in the development of the currently valid procedures, and therefore we know exactly which requirements a proper geodetic base plan must meet.
To accept an order for a topographic survey, it is necessary to know the area to be surveyed, the required scale of the plan, and the required format of the digital data. It is also important to determine whether any special requirements apply. While these issues may be complex for a typical client, we assist in finding the most appropriate solution.
The designer is the competent party to define the terms of reference. Often, topographic surveying is included as part of the design or planning contract with the client.
Engineering geology
Engineering geology (also referred to as engineering geological surveying or engineering geology) deals with the investigation of the properties of soil and bedrock for design purposes, while geotechnics adds the calculations required for design and the construction of foundations.
The geological structure of the subsurface in Estonia is highly diverse. As a foundation base, there are competent bedrock formations, but also Quaternary soils with highly variable and often unfavorable properties from a construction perspective (clays, sands, gravels, tills, peat, and mud).
Engineering geological (and geotechnical) investigations are essentially required for the design of structures to be built under virtually any geological conditions. It is not even a question of whether the structure is large or small; rather, it is about the level of risk one is willing to assume. Errors arising from insufficient consideration of foundation issues are extremely difficult—and often impossible—to rectify later. If a roof leaks, you look for a ladder; but if the foundation fails, there are no simple solutions.
Without engineering geological investigations, the outcome may be:
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a foundation with insufficient bearing capacity, resulting in excessive structural deformations (tilting, cracking, risk of failure);
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an over-dimensioned foundation—simply unnecessarily expensive;
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construction in an unfavorable location or on an unsuitable soil layer, resulting either in structural deformation or excessive moisture problems.
Engineering geological investigations are also required for the design of infrastructure structures (roads, railways, pipelines, port facilities, etc.). This applies even when the bearing capacity of the soils appears favorable at first glance, as excavation categories must still be determined. When preparing a detailed spatial plan, it is also useful to be aware of the engineering geological conditions of the planned area, which may vary significantly even within a single residential plot.
The main methods of engineering geological investigation include the drilling of boreholes, in-situ soil testing, and laboratory testing. As a result of the investigations, an engineering geological investigation report is prepared, providing indispensable information to the designer for making design decisions and calculations. Engineering geological data enable the rational design of building foundations.
Engineering geological investigations are carried out in accordance with the Procedure for Carrying Out Engineering Geological Investigations, and the technical aspects of the investigations are regulated by various standards.
For REIB, engineering geological investigations are one of our core service areas. We have extensive experience, expertise, and modern technical equipment to perform this work professionally.
To order an engineering geological / geotechnical investigation from REIB, it is usually sufficient to know where and what is planned to be built. The investigation program and scope are planned and agreed with the client already at the quotation stage. The designer plays an important role in defining the terms of reference, as in many cases they are the direct user of the obtained results.
For placing an order or requesting a price quotation, please contact:
Indrek Heidemaa
Tel. +372 733 7143, +372 523 5688
Email: indrek(at)reib.ee
or Tel. +372 733 7150, reib(at)reib.ee
