Pore-forming method of compacted density test holes for thick-layer roller compacted concrete

Abstract

The invention discloses a pore-forming method of compacted density test holes for thick-layer roller compacted concrete, comprising the following steps: pouring lower-cushion concrete or the roller compacted concrete, and then embedding a locating base on the poured lower-cushion concrete or the roller compacted concrete; installing a pore-forming steel tube on the embedded locating base; spreading the concrete, shielding a pipe orifice of the pore-forming steel tube when the spread concrete is slightly lower than the pipe orifice of the pore-forming steel tube, and continuously spreading theconcrete; and after completing the concrete spreading, carrying out rolling compaction on the concrete, and then opening the shielded pore-forming steel tube after the concrete is compacted to finally obtain the density test holes. The pore-forming method of the compacted density test holes for the thick-layer roller compacted concrete of the invention ensures detection accuracy of compacted density for the thick-layer roller compacted concrete, shortens detection time of the compacted density for the thick-layer roller compacted concrete, accelerates construction progress for the thick-layerroller compacted concrete, and lowers construction cost for the roller compacted concrete.

Description

technical field [0001] The invention relates to a method for forming a hole for detecting the compaction density of thick-layer roller compacted concrete, in particular to a method for forming the hole for detecting the hole for the compaction density of thick-layer roller-compacted concrete (RCC) dam in water conservancy and hydropower engineering. Background technique [0002] Due to the characteristics and advantages of RCC dam construction technology, such as simple process, full-section, short-interval rapid continuous construction, less cement consumption, strong adaptability, high equipment utilization rate, and high safety, it has quickly become the mainstream dam type of dam construction. Due to the limitation of the effective depth of equipment rolling, the traditional construction technology of RCC dams is to use a thin-layer rolling process with a thickness of about 35cm and a compaction thickness of about 30cm, and a density detector (meter) with a detection dept...

AI Technical Summary

Problems solved by technology

[0003] RCC dams are constructed with thick-layer rolling technology, which can speed up the construction progress, reduce construction costs, and improve project quality. However, there are still major deficiencies in the hole-forming method of the compaction density detection hole: the double-rod density detector (calculated ) is made by drilling holes with steel skewers. After the concrete is rolled and compacted, a steel plate with two holes is placed on the concrete surface to be tested. The steel skewers are inserted into the holes of the steel plate and hammered manually. To the depth to be tested, and then pull out the steel skewer, the drilling will produce pre-compression of the concrete between the two holes, after the iron drill is pulled out from the hole, the concrete between the two holes will rebound a little or the concrete will fall into the hole, The distance between the two holes is reduced or blocked, making it difficult or even impossible to insert the two measuring rods with a fixed distance into the hole

There are two methods for forming the detection hole of the single-rod density detector (meter), one method is basically the same as the double-rod detector (meter) (the difference is that only one hole is needed); the other method is After the concrete is rolled and compacted, special equipment is used to drill holes and then embed steel pipes. The speed of drilling and embedding pipes is slow, which affects the construction progress

In addition, the current detection hole forming method causes the concrete around the hole to loosen greatly when the hole is formed, which affects the detection accuracy of the concrete compaction density.

The deficiencies of these detection hole-forming methods have restricted the development of thick-layer roller compacted concrete construction technology.

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