RU2843700C1 - Installation method of adhesive anchor - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to construction and can be used in production of installation works for attachment of building elements and equipment to concrete or reinforced concrete structures with straight or conical anchor bolts. Method of installing adhesive anchor includes drilling a well in a concrete or reinforced concrete structure, well filling with cement-sand mortar with further installation of a bolt with simultaneous sealing of the mortar by imparting vibration oscillations or impact-rotary movement to the bolt; at that, cement-sand mortar has water-cement ratio of 0.3-0.4. Prior to immersing the bolt into the well filled with cement-sand mortar, high-voltage electrodes connected to high-voltage pulse generator are immersed. Next, in the filled with cement-sand mortar well shaft, an electrohydraulic shock is performed, which leads to a sharp increase in pressure therein, which leads to intensification of the process of hydration of the adhesive composition and an increase in the depth of hydration of the cement grains, as well as to a significant increase in the adhesion and diffusion component of adhesion of mature concrete with freshly laid mortar in the anchor well, after which high-voltage electrodes are removed from the anchor well.

EFFECT: reducing the time interval required for the anchor glued using the cement-sand mortar to put into operation, increasing the adhesion force of the adhesive composition with the finished concrete or reinforced concrete structure, improving strength properties of the adhesive composition.

1 cl, 6 dwg

Description

The invention relates to construction and can be used in the production of installation work to secure building elements and equipment to concrete or reinforced concrete structures using straight or conical anchor bolts.

A method is known for installing a straight smooth anchor bolt into a drilled hole, followed by securing the bolt with a cement-sand mortar and compacting it with a special device with a vibrator that fits into the gap between the bolt and the hole (Recommendations for securing smooth foundation bolts using vibration caulking. Kharkov. 1974, pp. 5-7).

However, when using cement-sand mortar, a special non-standard device is required for each bolt diameter, allowing the mortar to be compacted in the gap between the bolt and the borehole walls, while the proposed water-cement ratio significantly complicates the manufacturing process of such anchors. One of the key disadvantages of the method is the significant period of time it takes for the adhesive composition to gain the required strength indicators in the borehole.

An “Anchor device” (SU763525 17.09.80, E02D5/74) is known, which includes a rod secured in a well using a cement-sand mortar with a shank made in the form of a body of revolution narrowed in the upper part.

However, to put the anchor device into operation, it is necessary to wait for a significant period of time for the adhesive composition to gain strength, which must be no less than the design strength of the concrete structure.

The closest in technical essence to the claimed invention is the "Method for installing a wedging anchor bolt" (SU 737573 05.06.1980, E02D27/44, F16M9/00), which includes drilling a borehole in a concrete or reinforced concrete structure, filling the borehole with a cement-sand mortar, followed by installing a bolt with simultaneous compaction of the mortar, wherein the cement-sand mortar has a water-cement ratio of 0.3-0.4. Compaction of the cement-sand mortar is performed by imparting vibration oscillations or impact-rotational motion to the bolt.

However, this method does not eliminate the key drawback of adhesive anchors made on the basis of cement-sand mortar, namely the necessary interval for achieving the required strength indicators of the adhesive composition equal to at least the strength of the concrete structure.

The objective of the claimed invention is to create a method for installing an adhesive anchor that would make it possible to significantly reduce the time interval required for an anchor, glued using a cement-sand mortar, to be put into operation.

The stated problem is solved in that in the "Method of installing an adhesive anchor", including drilling a hole in a concrete or reinforced concrete structure, filling the hole with a cement-sand mortar, followed by installing a bolt with simultaneous compaction of the mortar by imparting vibration oscillations or impact-rotational motion to the bolt, wherein the cement-sand mortar has a water-cement ratio of 0.3-0.4, according to the invention, that before immersing the bolt in a hole filled with a cement-sand mortar, high-voltage electrodes connected to a high-voltage pulse generator are immersed, then an electrohydraulic shock is performed in the borehole filled with a cement-sand mortar, leading to a sharp increase in pressure in it, which leads to an intensification of the hydration process of the adhesive composition and an increase in the depth of hydration of the cement grain, as well as to a significant increase in the adhesive and diffusion component of the adhesion of mature concrete to freshly laid solution in the anchor hole, after which the high-voltage electrodes are removed from the anchor hole.

A multiple reduction in the time interval required to put the anchor into operation is achieved by using the electrohydraulic effect in the limited space of the well, as a result of which a sharp increase in pressure occurs, which leads to an intensification of the hydration processes of the adhesive composition and an increase in the depth of hydration of the cement grain, by increasing the number of active surfaces of the binder particles, activating the hydration processes of the liquid medium, a sharp increase in the number of free charge carriers, and also significantly increasing the adhesive and diffusion components of the bond between mature concrete and freshly laid mortar in the anchor well.

Fig. 1-6 schematically shows the order of operations when installing an anchor bolt into a borehole of a finished concrete or reinforced concrete structure.

The method is carried out as follows.

The perforator 2 is used to drill a hole in the finished concrete or reinforced concrete structure 1. The components of the cement-sand mortar, water, cement and sand, are divided into pre-calculated portions to obtain a plastic mortar 4 with W/C=0.3-0.4. The components are thoroughly mixed. Then the resulting cement-sand mortar 4 is placed in the anchor hole 3, filling it at least 2/3 full. After filling the borehole 3 with the solution 4, high-voltage electrodes 5 connected to the high-voltage pulse generator 7 are immersed in it. In the borehole 3 filled with the cement-sand solution 4 at the required depth, an electrohydraulic shock 6 is created, after which the high-voltage electrodes 5 are removed from the borehole 3. The bolt 8 is immersed using the perforator 2, which imparts to the bolt 8 the vibration oscillations or impact-rotational motion necessary for compaction and uniform distribution of the cement-sand solution 4 over the surface of the borehole 3 and the anchor 8. The completed unit is maintained for the required time interval, allowing it to gain the necessary bearing capacity for further commissioning.

The technical result of the claimed invention is a multiple reduction in the time interval required to put the anchor into operation; the adhesive and diffusion components of the bond between mature concrete and freshly laid mortar in the anchor hole are also noticeably enhanced.

The use of the proposed invention allows:

1. Reduce the time interval required from the manufacture of the anchor to its commissioning by up to 4 times, compared to anchors constructed without the use of electrohydraulic impact (electrophysical impact);

2. Increase the strength properties of the adhesive composition (cement-sand mortar) by up to 35%, compared to the adhesive composition that has not been subjected to electrohydraulic shock;

3. Increase the adhesive strength of the adhesive composition (cement-sand mortar) with the finished concrete or reinforced concrete structure by up to 38%, compared to the technology without the use of electrohydraulic impact.

Claims (1)

A method for installing an adhesive anchor, which includes drilling a borehole in a concrete or reinforced concrete structure, filling the borehole with a cement-sand mortar, followed by installing a bolt with simultaneous compaction of the mortar by imparting vibrations or impact-rotational motion to the bolt, wherein the cement-sand mortar has a water-cement ratio of 0.3-0.4, characterized in that, before immersing the bolt in the borehole filled with the cement-sand mortar, high-voltage electrodes connected to a high-voltage pulse generator are immersed, then an electrohydraulic shock is performed in the borehole filled with the cement-sand mortar, leading to a sharp increase in pressure in it, which leads to an intensification of the hydration process of the adhesive composition and an increase in the hydration depth of the cement grain, as well as to a significant increase in the adhesive and diffusion component of the bond of mature concrete with freshly laid mortar in the anchor borehole, after which The high-voltage electrodes are extracted from the anchor hole.