Surveying is a science that studies the shape and size of the earth and determines the position of the ground. Its content includes two parts, namely measurement and layout. Measurement refers to the use of measuring instruments and tools, through measurement and calculation, to obtain a series of measurement data or results, and to draw the terrain of the earth's surface into topographic maps for economic construction, national defense construction, planning and design and scientific research. Setting-out (lofting) refers to calibrating the plane position and elevation of the buildings (structures) planned and designed on the design drawings with certain measuring methods and accuracy on the spot as the basis of construction.
Surveying includes geodesy, general surveying, photogrammetry, oceanography, engineering surveying and cartography. This textbook mainly introduces the contents of general surveying and some architectural engineering surveying, so that the knowledge of architectural engineering surveying can be applied to serve its professional work.
Surveying is a long history science. As early as thousands of years ago, due to the needs of social production development at that time, working people in China, Egypt, Greece and other countries began to create and use measuring tools to measure. In ancient times, China invented measuring instruments such as compass and armillary sphere, which made great contributions to astronomy, navigation and surveying and mapping. With the demand of human society and the development of modern science and technology, surveying and mapping technology has developed from conventional geodesy to space satellite geodesy, from aerial photogrammetry to the application of space remote sensing technology; The measured object extends from the surface of the earth to the space planet, from static to dynamic; Measuring instruments generally tend to be accurate, electronic and automatic. Since the founding of New China more than 50 years ago, China's surveying and mapping industry has flourished, and encouraging achievements have been made in astronomical geodesy, satellite geodesy, aerial photography and remote sensing, precision engineering surveying, modern adjustment calculation, development of surveying instruments and training of surveying and mapping talents. China's surveying and mapping science and technology has been in the advanced ranks in the world.
Measurement technology is an important means to understand and transform nature, and it is also the basic, early and ultra-early work in national economic construction, and it is widely used. It can provide topographic maps or thematic maps of various scales and surveying and mapping materials for urban planning, municipal engineering, land and real estate development, agriculture, disaster prevention and scientific research. At the same time, according to the requirements of the planning and design department, the road planning alignment and land allocation survey, as well as the survey and measurement of municipal engineering, industrial and civil construction projects, directly serve the design and construction of construction projects. In the process of engineering construction and operation management, the settlement, displacement and inclination of high-rise and large-scale buildings (structures) are observed to ensure the safety of buildings (structures) and provide various reliable measurement data for the study of building structures and foundations. Therefore, the survey work will directly affect the project quality and the realization of expected benefits, and it is an indispensable and important work in China's modernization. With the development of surveying and mapping technology and the research and application of new technologies, it will provide more and better information services and accurate and applicable surveying and mapping results for various industries in time.
Second, the task and role of construction engineering survey
Construction engineering investigation is all kinds of investigation work needed by industrial and civil buildings in the stages of investigation, design, construction and management. Its tasks are:
1) Use various measuring instruments and tools to determine the mutual position of ground points, and draw the shape and size of the ground into topographic map according to a certain scale for planning and design.
2) According to the requirements of design drawings, arrange the location and size of the proposed building on the construction ground. This kind of work is usually called lofting, also known as construction lofting or setting out.
3) After completion, completion survey must be carried out to provide reliable data for project acceptance, expansion and reconstruction. Sometimes, in order to identify the engineering quality of buildings, monitor the operation of buildings, or provide information for the scientific research of building structures and foundations, it is necessary to observe the settlement, displacement and inclination of these buildings during the construction process and management stage.
As mentioned above, the survey work actually runs through the whole process of building engineering, and its quality is directly related to the speed and quality of engineering construction. With the vigorous development of China's modernization, the speed and complexity of engineering construction are getting higher and higher, and the accuracy and speed of surveying work should also be improved accordingly.