The building function of a dry coal shed is mainly large storage warehouse, so it must have certain storage and working space, that is, the structure must be able to meet certain clearance requirements, and its effective use space section shape is trapezoidal, the envelope of the working space is close to the arc. The length and width of the dry coal shed structure are determined according to the needs of installed capacity, while the height of the structure is determined by the operating requirements of coal heaps and bucket turbines. Therefore, the dry coal shed structure is characterized by a large span, high height, and wide coverage area.
Due to the processing, construction, and other reasons of space frame parts, there are often surface defects or damages in building structural engineering, such as beam bending, weld cracking, and so on. These visible damage or defects are easy to attract people’s attention, timely diagnosis and measures to repair and maintenance.
In recent years, space frame structure accidents occur frequently, even the collapse of the whole building, which indicates that there are often internal defects in the components. These invisible potential defects are sometimes more dangerous and often cause large economic losses. Therefore, how to analyze and judge whether the space frame structure is defective through certain monitoring means, and where they may be, has become an international research focus.
In order to prevent the deformation and collapse of the space frame, the displacement monitoring device should be set up to monitor the deformation and node displacement of the space frame. In the past, it was considered that the space frame was a high-order statically determinate structure, which would not collapse even if local members were damaged, and had a large safety reserve. In fact, there are many factors that may affect the safety of the space frame structure, such as the safety and reliability of the design, the geometric deviation of the structure shape, the deviation of the external load point, Initial bending of structure bearing deviation, bar, bar corrosion, structure characteristics, modulus of elasticity, the strength of materials used, the section size of deviation, the installation process of components deflection more than code requirements, such as improper sliding in the process of assembling method can make the internal force distribution of the spatial space frame structure or local compression bar buckling or the pull rod failure cause internal force redistribution and cause other bar broken Bad, from “progressive destruction” to form a “domino effect”, eventually lead to the collapse of the space frame structure.
If the problem is found when the space frame structure is abnormal, and people are reminded to take remedial measures as soon as possible, the process of gradual destruction can be interrupted. The space frame system can detect abnormal deformation and displacement caused by load transfer of the space frame in time, and give an alarm when the deformation of the space frame exceeds the critical value allowed by design, prompting and allowing maintenance personnel to take corresponding measures. Avoid the overall collapse of the space frame dry coal shed. Because of the large size of the space frame structure, the displacement changes under different loads can be observed.