Snap ring type anchorage force measuring device

Abstract

The invention provides a snap ring type anchorage force measuring device, wherein each of one or 3-5 steel stranded wire(s) to be measured is externally provided with a clamping piece, each clamping piece is externally provided with an anchor ring, each anchor ring is externally provided with a snap ring, an upper support block and a lower support block of which the centre line is arranged on the same diameter are arranged between the outer surface of the snap ring and the outer ring of the anchor ring, a spring is internally arranged between two opened ends of the snap ring, the outer end of the snap ring is provided with a position adjusting rod connected with a dial indicator, strain transducers which are formed by connecting strain pieces are respectively arranged at the inner side and the outer side of the snap ring and the symmetric position of the diameter direction of the centre line of the opening end of the snap ring, and the strain transducers are connected with a computer through lead wires. The device provided by the invention has the advantages of being convenient to install, good in stability, high in measurement precision, capable of being repeatedly used and the like, so that the device can be used for monitoring the tension force of the steel stranded wires in the process of prestressed concrete structure engineering construction, and the anchorage force of an anchorage device can meet the design requirement.

Description

technical field [0001] The invention belongs to the technical field of force measuring equipment or devices, and in particular relates to a testing instrument for an anchorage steel strand assembly. Background technique [0002] At present, prestressing technology is widely used in civil engineering. In the construction of prestressed concrete structures, most of them adopt the post-tensioning method: that is, the component concrete is poured first, and holes are reserved or casings are buried in it. After the concrete reaches the required strength, at least one or more steel strands are inserted into the reserved tunnel, supported on the end of the concrete component by a jack, and the steel strand is stretched, so that the component is simultaneously compressed by the counter force, and the tension is maintained. To control the tension, the size of the control tension is indirectly measured by the oil pressure gauge on the tensioning equipment, that is, the steel strand is...

AI Technical Summary

Problems solved by technology

Due to factors such as the slippage of the prestressed tendons, the shrinkage of the prestressed tendon, and the friction loss of the anchor mouth during the anchoring process of the YJM anchorage, there is obviously an error in the value of the control tension. If the error is too large, the prestress of the component will be less than the design value. Thus leaving engineering hidden dangers (accidents with small pre-compression stress values ​​often occur in engineering construction, resulting in small pre-camber of girders, cracking of components in severe cases, etc.)

In order to ensure the quality of the project, accurately obtain the size of the anchoring force, and reasonably estimate the anchoring force loss value of the YJM anchorage during the anchoring process due to the slippage, shrinkage of the prestressed tendon, and the friction loss of the anchor mouth. A pressure-strain sensor is installed between the anchor plate and the anchor to accurately measure the anchoring force value, but this method can only be used for research and cannot be widely promoted in engineering, because firstly, the pressure-strain sensor will take up space, which will change the The design of the structural geometry; the second is that the pressure and strain sensors cannot be reused, thus increasing the project cost, because each pressure and strain sensor ranges from several hundred yuan to several thousand yuan

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