CN219302457U - Auxiliary device for concrete autogenous volume deformation test - Google Patents

Abstract

The utility model relates to an auxiliary device for a concrete autogenous volume deformation test, which is applied to the position of an axle center in a concrete test piece, wherein the concrete test piece consists of concrete mixture which is filled into a test piece cylinder for three times, a bracket for placing the concrete mixture on the top of the test piece cylinder is arranged, a through hole for placing a positioning sleeve is arranged on the bracket at the position corresponding to the axle center of the test piece cylinder, and the positioning sleeve is used for placing the strain gauge at the position of the axle center of the concrete test piece through the positioning sleeve after the concrete mixture is filled into the test piece cylinder. When concrete mixture is sequentially filled into the test piece cylinder, the support is placed on the test piece cylinder, the through holes in the support and the test piece cylinder are coaxial, the positioning sleeve penetrates through the through holes and stretches into the test piece cylinder, and the strain gauge is arranged at the axial center position of the concrete mixture in the test piece cylinder through the positioning sleeve. The utility model is suitable for the technical field of concrete test detection devices.

Description

Auxiliary device for concrete autogenous volume deformation test

Technical Field

The utility model relates to an auxiliary device for a concrete autogenous volume deformation test. The device is suitable for the technical field of concrete test detection devices.

Background

The volume deformation of concrete caused by the hydration of the cementing material is called autogenous volume deformation under the constant temperature and absolute humidity conditions, and the size of the volume deformation is mainly determined by the variety of cement, the dosage of cement, the variety of the mixed materials, and the like. Autogenous volume deformation is one of the key indexes for evaluating crack resistance of dam concrete, and from the viewpoint of preventing cracking of concrete, it is desirable to reduce autogenous volume shrinkage of concrete as much as possible.

The concrete autogenous volume deformation test is carried out in a constant temperature environment of (20 ℃ 2), at least two test pieces are adopted in each group, a cylindrical test piece with the diameter of 200mm and the height of 500-600 mm is adopted in the test, aggregates with the particle size of more than 40mm are screened out by a wet screening method before forming, concrete mixture is filled into a test piece cylinder in three layers, a first layer is filled and is inserted and compacted, a strain gauge is vertically fixed in the center of the test piece cylinder, a second layer is filled and is inserted and compacted, in the process, the strain gauge is timely adjusted to be positioned in the middle of the test piece, a measuring base line coincides with the longitudinal axis of the test piece, and finally the third layer is filled and is vibrated and compacted on a vibrating table. After the test piece is molded, water loss is avoided, a cover plate is added as soon as possible, a gap between the cover plate and the test piece cylinder and a cable outlet of the strain gauge are sealed, the sealed test piece is placed into a thermostatic chamber for testing, and vibration and impact are avoided during the test.

At present, manual hand strain gauges are mostly adopted for installing strain gauges, and the strain gauges are visually inspected to keep the coincidence with the longitudinal axis of a test piece. In actual operation, the concrete charging operation is affected, the work efficiency is low, and the strain gauge cannot be ensured to be perpendicular to the longitudinal axis of the test piece and coincide, so that the accuracy of the test result is affected.

Disclosure of Invention

The utility model aims to solve the technical problems that: the utility model provides an auxiliary device for a concrete autogenous volume deformation test, which aims to solve the problems of low work efficiency and poor accuracy in installing strain gauges in manual hand-mounted strain gauges.

The technical scheme adopted by the utility model is as follows: the utility model provides a concrete autogenous volume deformation test's auxiliary device, is applied to and installs the axle center position department in the concrete test piece with the strainometer, and the concrete test piece comprises the concrete mixture that packs into test piece section of thick bamboo by three times, its characterized in that: the device is provided with a support used for being placed at the top of the test piece cylinder, a perforation used for placing a positioning sleeve is arranged on the support at a position corresponding to the axial center of the test piece cylinder, and the positioning sleeve is used for placing a strain gauge at the axial center position of a concrete test piece through the positioning sleeve after concrete mixture is filled into the test piece cylinder. When concrete mixture is sequentially filled into the test piece cylinder, the support is placed on the test piece cylinder, the through holes in the support and the test piece cylinder are coaxial, the positioning sleeve penetrates through the through holes and stretches into the test piece cylinder, and the strain gauge is arranged at the axial center position of the concrete mixture in the test piece cylinder through the positioning sleeve.

And baffle plates matched with the outer wall of the test piece cylinder are arranged at two ends of the support. So, make things convenient for the installation of support, through remove support both ends baffle and test piece section of thick bamboo outer wall cooperation position department to the support, realize the location and the spacing of support, make the perforation on the support be located the axle center position department of test piece section of thick bamboo steadily.

The locating device is characterized in that a locating ring used for guiding a locating sleeve installed in the clamping hole is arranged on the support at the clamping hole position along the vertical direction, the locating ring is fixedly connected to the support through a connecting rod, and the inner wall of the locating ring is matched with a shaft hole on the outer wall of the locating sleeve. Therefore, the positioning sleeve is mounted on the support through the positioning ring to always keep coaxial with the test piece cylinder, and the positioning sleeve is prevented from inclining in angle when passing through the clamping hole.

The locating sleeve is provided with a sleeve mounting hole in a penetrating mode along the diameter direction of the locating sleeve, a clamping nail is arranged in the sleeve mounting hole, and the clamping nail extending out of the sleeve mounting hole is connected with the support through the upper top surface of the support. Therefore, when the positioning sleeve moves to the position above the support, the clamp pin is matched with the upper top surface of the support after passing through the sleeve mounting hole, so that relative sliding between the positioning sleeve and the support in the vertical direction is avoided.

The bracket, the baffle, the connecting rod, the positioning ring and the positioning sleeve are all made of organic glass or metal.

The beneficial effects of the utility model are as follows: according to the utility model, the baffles at the two ends of the bracket are matched with the outer wall of the test piece cylinder, the bracket is clamped on the test piece cylinder, so that the positioning sleeve is positioned at the axial center position of the test piece cylinder, the strain gauge arranged in the test piece cylinder through the positioning sleeve is conveniently arranged at the axial center position of the test piece cylinder, and the working efficiency of the strain gauge installation is improved; according to the utility model, the locating ring is arranged at the position of the perforation on the support, and the clamping nail penetrating through the locating sleeve is matched with the upper top surface of the support, so that the locating sleeve is stably arranged on the support along the axial center direction of the test piece cylinder.

Drawings

Fig. 1 to 2: the structure of the utility model is schematically shown.

In the figure: 1. a bracket; 2. a baffle; 3. perforating; 4. a connecting rod; 5. a positioning ring; 6. positioning the sleeve; 7. a sleeve mounting hole; 8. and (5) clamping nails.

Detailed Description

The present utility model will be described in further detail by way of examples with reference to the accompanying drawings, which are illustrative of the present utility model and not limited to the following examples.

The embodiment is an auxiliary device for a concrete autogenous volume deformation test, which is provided with a support 1 used for being placed on a test piece cylinder, wherein two ends of the support 1 are slightly longer than the diameter of the test piece cylinder, baffle plates 2 matched with the outer wall of the test piece cylinder are arranged below two ends of the support 1, and the support 1 is clamped on the test piece cylinder by moving the support 1 to the position where the baffle plates 2 at two ends of the support 1 are matched with the outer wall of the test piece cylinder. At this time, the through hole 3 provided at the intermediate position of the holder 1 is at the axial center position of the test piece cylinder and is coaxial with the test piece cylinder.

In this embodiment, the through hole 3 provided at the middle position of the bracket 1 is used to pass through the positioning sleeve 6, and the positioning ring 5 is installed below the bracket 1 at the position of the through hole 3 through the connecting rod 4. The positioning sleeve 6 penetrating through the perforation 3 is positioned at the axial center of the test piece cylinder under the action of the positioning ring 5, the strain gauge can be arranged at the central position of the concrete mixture through the positioning sleeve 6, the positioning ring 5 plays a guiding role on the positioning sleeve 6, and the positioning sleeve 6 is prevented from deflecting in the process of extending into the perforation 3.

In this embodiment, a sleeve mounting hole 7 is formed in the positioning sleeve 6 along the diameter direction of the positioning sleeve 6, a clip 8 is mounted in the sleeve mounting hole 7, and two ends of the clip 8 extend out of the sleeve mounting hole 7. In the process of loading the positioning sleeve 6 into the test piece cylinder through the through hole 3, the clamping nail 8 extending out of the positioning sleeve 6 is matched with the upper top surface of the bracket 1, so that relative sliding between the positioning sleeve 6 and the bracket 1 in the vertical direction is avoided.

In this embodiment, the bracket 1, the baffle 2, the connecting rod 4, the positioning ring 5 and the positioning sleeve 6 are all made of organic glass or metal.

The application method of the embodiment is as follows: before the concrete autogenous volume deformation test, various materials are weighed according to the proportion of the designed concrete mixing proportion, and are stirred by a concrete stirrer to prepare cement concrete, the cement concrete is filled into test piece cylinders in three layers, and the height of each layer is 1/3 of that of the test piece cylinder.

After the first layer of cement concrete is filled and is evenly inserted and rammed by a ramming rod, the device is sleeved on the cylinder mouth of the test piece cylinder, a positioning sleeve 6 penetrates through the perforation 3 and the positioning ring 5, a clamping nail 8 penetrates through a sleeve mounting hole 7 on the positioning sleeve 6, and positioning and fixing are carried out on the positioning sleeve 6; placing a strain gauge into the positioning sleeve 6, wherein the lower end of the strain gauge is contacted with the top surface of the first layer of concrete, and the middle position of the strain gauge is positioned at the middle position in the test piece cylinder; then, the second layer of cement concrete is filled to the height of 2/3 of the test piece cylinder, the cement concrete is tamped by a tamping rod, then the clamping nails 8 are pulled out from the positioning sleeve 6, the parts of the device except the positioning sleeve 6 are removed, the top end of the positioning sleeve 6 is held by hands, then the third layer of cement concrete is filled, after the tamping is completed, the positioning sleeve 6 of the device is slowly pulled out, the test piece cylinder is slightly hammered to make the cement concrete fully contact with the strain gauge, after the positioning sleeve 6 is completely pulled out, the test piece cylinder is placed on a vibrating table to vibrate and compact the concrete, the cover plate is added to the test piece cylinder opening immediately, the gap between the cover plate and the test piece cylinder and the cable outlet of the strain gauge are sealed, and the sealed test piece is placed in a thermostatic chamber for testing. The pipe diameter of the positioning sleeve 6 is far smaller than the diameter of the test piece cylinder, so that after the concrete mixture is filled in the test piece cylinder, the positioning sleeve 6 is taken out from the test piece cylinder and is knocked by a rubber hammer, the influence on a concrete test piece formed by the concrete mixture in the test piece cylinder is small, and meanwhile, the installation position of the strain gauge is basically not influenced.

The foregoing is only a preferred embodiment of the present utility model, but the scope of the present utility model is not limited thereto, and any person skilled in the art, who is within the scope of the present utility model, should make equivalent substitutions or modifications according to the technical scheme of the present utility model and the inventive concept thereof, and should be covered by the scope of the present utility model.

Claims (5)

1. The utility model provides a concrete autogenous volume deformation test's auxiliary device, is applied to and installs the axle center position department in the concrete test piece with the strainometer, and the concrete test piece comprises the concrete mixture that packs into test piece section of thick bamboo by three times, its characterized in that: the device is provided with a support (1) used for being placed at the top of the test piece cylinder, a perforation (3) used for placing a positioning sleeve (6) is arranged on the support (1) at a position corresponding to the axial center of the test piece cylinder, and the positioning sleeve (6) is used for placing a strain gauge at the axial center position of a concrete test piece through the positioning sleeve (6) after concrete mixture is filled into the test piece cylinder.

2. An auxiliary device for concrete autogenous volume deformation test as defined in claim 1, wherein: both ends of the bracket (1) are provided with baffle plates (2) matched with the outer wall of the test piece cylinder.

3. An auxiliary device for concrete autogenous volume deformation test as defined in claim 1, wherein: the positioning device is characterized in that a positioning ring (5) used for guiding a positioning sleeve (6) arranged in the clamping hole is arranged on the support (1) in the vertical direction at the clamping hole position, the positioning ring (5) is fixedly connected to the support (1) through a connecting rod (4), and the inner wall of the positioning ring (5) is matched with a shaft hole on the outer wall of the positioning sleeve (6).

4. An auxiliary device for a concrete autogenous volume deformation test as defined in claim 3, wherein: the locating sleeve (6) is provided with a sleeve mounting hole (7) in a penetrating mode along the diameter direction of the locating sleeve (6), a clamp nail (8) is arranged in the sleeve mounting hole (7), and the clamp nail (8) extending out of the sleeve mounting hole (7) is connected with the upper top surface of the support (1) to connect the locating sleeve (6) with the support (1).

5. An auxiliary device for a concrete autogenous volume deformation test as defined in claim 3, wherein: the bracket (1), the baffle (2), the connecting rod (4), the positioning ring (5) and the positioning sleeve (6) are all made of organic glass or metal.

Images