Surveying today has found wide application in a variety of industries. One of these areas is cadastral relations. In industry, without such work, mining is impossible. But geodetic works in construction are especially important. This is due to the need for high measurement accuracy in the design and construction of both industrial facilities and civil buildings. That is why the importance of geodetic work in construction is difficult to overestimate.
General content of the concept
The result of engineering and geodetic surveys is information on the nature of the relief of the area where construction work is ahead. Specialized companies are engaged in them, the task of which is to build and develop survey networks (planned and high-altitude), determine the coordinates of key points on the boundaries of land plots, conduct and timely update topographic surveys, identify and mark on maps the available engineering communications (both underground and ground) )
In their activity, surveyors rely on source data that contain topographic maps of the area. The process of operating the facility also involves the implementation of a number of specific engineering and geodetic tasks. Almost everywhere, it is required to process and refine design and working documentation, conduct reference and alignment work, control the geometric parameters of buildings, and conduct executive surveys.
In addition, geodetic works in construction include the task of monitoring the settlement and deformation of the earth's surface and construction sites, including as part of the monitoring of hazardous natural processes. They also know how to measure, that is, determine the parameters of buildings and a variety of architectural forms. In addition, the verticality of structures and columns is controlled, crane tracks are verified. Installation of any complex type of equipment is not complete without such work.
Types of geodetic works in construction
What are the applied directions of modern geodesy? There are a considerable number of them. Specialists create a reference geodetic network at the object, it is tied to absolute elevation marks and to the coordinate system existing in this place. The construction site is planned in the vertical and horizontal directions, the necessary volumes of earthwork are calculated, the design axes outside and inside the building are taken out in kind. Construction objects are planned vertically, their area, volume and perimeter are determined.
Geodetic works in construction are used in the installation of factory equipment and the installation of complex instruments. An important place was allotted to him when arranging railway tracks and crane rails. They are also being conducted during the construction of linear structures, columns, towers, all kinds of antennas, cameral and field tracing. This type of work is also in demand in the field of underground communications.
In fact, an executive survey is carried out, which reveals all deviations from the solutions specified in the project. The geometric parameters of the object are also monitored during the construction process. Modern methods for the production of geodetic works allow you to create executive plans and schemes in electronic form or in the form of 3D-models.
What are they made of?
Any geodetic work in construction can be divided into three main stages. The first of them (preparatory) includes the formation of technical specifications, which must contain a list of the most important points. We are talking about the location of the future object on the territory and in space, its size and volume. Next, a list of upcoming work is being specified. It can consist of a topographic survey, a breakdown of the territory, an executive survey, measurements, or control.
The customer can add a number of other wishes to the list. He also conducts control of geodetic works in construction. At this stage, all communications, both main and auxiliary, and their mutual arrangement are specified. In addition to the scope of work, the dates of their implementation and the form in which the report will be formulated are indicated.
At the preparatory stage, the collection and preparation of the necessary technical documents takes place. These include copies of existing topographic maps, situational plans with marked boundaries of sites and construction sites , master plans with outlines of future facilities.
A contract for a survey completes the preparatory phase of the geodetic work. Next, you need to stock up on data on the results of engineering work carried out on the construction site earlier. Without them, the task is complicated by an order of magnitude. Based on the terms of reference, the organizer of work thinks out a plan of future events taking into account all the existing conditions and restrictions.
The practical side of things
At the second stage of the work - field work - surveyors conduct reconnaissance of the area. This is a rather complicated process, because often the real conditions can differ significantly from those specified in the documents. The most important procedure of this stage is called topographic survey. It belongs to the most famous and sought-after varieties of engineering research and is carried out on different scales - from 1: 500 to 1: 5000.
According to the results of its surveyors are able to draw up a topographic plan. Modern events in the field are accompanied by the use of the latest technical means in the form of electronic and optical theodolites, laser levels, etc. Their use not only facilitates the hard work of surveyors, but also increases the accuracy of measurements by an order of magnitude.
What does the plan contain
On the compiled topographic plan should be displayed any elements of the terrain, which include buildings, and elevations, and large objects of vegetation. Without fail, all available underground utilities, such as pipelines or electric cables, should be recorded. If this point is not given enough attention, the consequences can be very serious. That is why the preparation of a topographic plan is the task of a highly qualified specialist.
Topographic surveys are useful not only for builders. Specialists in landscape design and those who applied for permission to develop a land plot cannot do without it. Thus, survey data are required almost everywhere, when it comes to land management procedures.
Final stage
The final stage of geodetic work is called a cameral or cabinet. On it, specialists specify the data obtained during the field work, and all the calculated parameters. Processing requires a significant flow of information, which implies the attention and high qualification of performers.
The technical report on the work done in the geodetic field is called an explanatory note and contains many numbers, drawings, diagrams and other data with the results of the work done. All documentation, duly executed, is transferred to the customer.
Who leads the process
The preparatory phase of work at the construction site is usually the responsibility of the customer-builder, the same tasks that relate directly to the construction process are most often performed by the contractor or general contractor. The customer and the general contractor may be representatives of different organizations, but sometimes they collaborate within the same investment and construction company.
The organization of geodetic works in construction depends on their complexity and volume. If a subcontracting organization is involved in the construction of an object, which includes geodetic specialists, all this work is carried out by them. If we are talking about a small object that does not involve complex surveys, geodetic tasks are solved directly by the builders themselves.
JV " Geodetic works in construction" - what kind of document?
Like any other type of work, geodetic surveys should be regulated. The purpose of this is to ensure the unity and accuracy of measurements and the transfer of data from field conditions to drawings and documents. Such regulation is reflected in the system of Construction Norms and Regulations (building codes and rules), as well as other higher standards adopted at the state level.
There are several basic documents that determine the content of various geodetic surveys in the field of construction, as well as the order and forms of their implementation. The leading one is SP 126 13330 2012 "Geodetic works in construction". The acronym JV stands for "building rules." This document is an updated version of the previously adopted SNiP "Geodetic works in construction" No. 3.01.03-84. They are the main guide containing instructions regarding all issues related to the organization of this type of work. As in the SNiP "Geodetic works in construction", they spell out any nuances related to the procedure for creating the alignment basis, acceptable accuracy, etc., numerous requirements are set forth for the standards of measurement errors in the geodetic sphere and various methods of transmitting marks.
In addition to the joint venture "Geodetic works in construction", other reference manuals also serve as a guide to the employees of the geodetic service. These can be developed for various fields of application and relate, for example, to the composition of executive documentation and its contents, the use of special instruments in geodesy, measurement procedures with a description of the necessary technologies, as well as the necessary recommendations related to geodetic work on the construction of high-rise and multi-purpose buildings .
What is PPGR
All recommendations that contain the set of rules "Geodetic works in construction" should be taken into account when drawing up a project for the production of geodetic works (PPGR), the presence of which is mandatory when it comes to the construction of a large and complex object or building with a height of 9 floors or more. Such a project contains the scope and methodology of the survey, planned dates, financial and organizational issues.
The contractor can develop the GCPF or he entrusts it to a specialized organization in agreement with the customer. The project must be formed and go into production no later than 2 months before the start of work.