Plug-in type steel pipe concrete column base for large power transmission tower and construction method thereof

Abstract

The invention belongs to the technical field of concrete-filled steel tubes, and particularly relates to a plug-in concrete-filled steel tube column base for a large power transmission tower and a construction method of the plug-in concrete-filled steel tube column base. The structure comprises a bottom pile foundation anchoring pier, a foundation bearing platform and insertion type steel pipe concrete which are sequentially arranged from bottom to top; a grouting opening is formed by a top pipe opening of the insertion type steel pipe concrete, a pressing plate is coaxially arranged in the grouting opening, an anchor plate is further arranged above the grouting opening, and the anchor plate and the pressing plate are connected through a middle rod. The concrete-filled steel tube column foot further comprises an axial pull rod and a tensioning nut used for tensioning the axial pull rod. The insertion type steel pipe concrete column base has the advantages of being simple in structure, reliable in force transmission, small in occupied space and convenient to construct, and a basic guarantee can be provided for normal and reliable use of the column base. The invention further provides a construction method based on the plug-in concrete-filled steel tube column base, so that the efficiency, accuracy and reliability of construction are practically improved.

Description

technical field [0001] The invention belongs to the technical field of steel pipe concrete, and in particular relates to a plug-in steel pipe concrete column base for a large power transmission tower and a construction method thereof. Background technique [0002] Concrete filled steel pipe is a composite structure formed by pouring concrete inside steel pipes; at this time, the internal concrete is constrained by the external steel pipes, and its compressive performance is significantly improved, while the external steel pipes are laterally supported by internal concrete, and the local stability is significantly improved. Compared with pure steel structures and pure reinforced concrete structures, steel pipe concrete structures have the advantages of high bearing capacity, superior shaping and seismic performance, material saving and simple construction, and have been widely used in recent years. In the construction of transmission towers, the connection construction of the...

AI Technical Summary

Problems solved by technology

In the construction of transmission towers, the connection construction of the end of large-scale steel pipe concrete inserted into the concrete foundation is a rare construction method, which is rarely used; especially the construction method of obliquely inserting the end into the foundation is even rarer, and many operations are mostly exploratory construction. The application of concrete filled steel tube towers in power transmission and transformation projects is hindered

However, in actual operation, most of the CFST inserted into the concrete foundation are designed as slanted columns, which tend to generate large tensile stress that is unfavorable to the concrete shell, causing the concrete shell to crack

In addition, because there are many ribs inside the steel pipe and the steel pipe is inclined, on the one hand, it is easy to form uniform cavities of different sizes, which makes it easy to produce internal voids during the concrete pouring process; on the other hand, when the mortar in the steel pipe concrete is solidified Finally, the horizontal grouting surface intersects with the flange joints of the upper and lower steel pipes, that is, the slope where the transition node is located, which will also cause part of the area where the transition joint is located to be covered by concrete while the other part is empty; combined with the cracking of the aforementioned concrete shell, Eventually, the stress in this area will be unbalanced, resulting in stress distribution defects, which will have a serious impact on the construction quality of the transmission tower, which needs to be resolved urgently

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