CN220455322U - Concrete shrinkage test device - Google Patents

Abstract

The utility model relates to a concrete shrinkage device, which comprises a bottom plate, wherein two sides of the upper end of the bottom plate are provided with indication plates, the two indication plates are in sliding connection with the bottom plate and do left-right linear motion relative to the bottom plate, in practice, the two indication plates can be tightly attached to concrete blocks placed above the bottom plate, a gap between the indication plates and the concrete blocks is observed through a period of time of placement, a user can be helped to quickly obtain rough concrete shrinkage data, the user can roughly judge the properties of the concrete blocks, the user can quickly compare a plurality of concrete properties to be detected conveniently, the lower ends of the indication plates are particularly provided with internal threaded holes in a penetrating manner from left to right, and a bidirectional screw rod is screwed in the corresponding internal threaded holes of the lower ends of the two indication plates, so that the two indication plates can be quickly attached to the concrete blocks, and the position of the concrete blocks can be restrained, and the whole stress of the concrete blocks on a supporting platform is balanced.

Description

Concrete shrinkage test device

Technical Field

The utility model relates to the technical field of concrete performance detection equipment, in particular to a concrete shrinkage test device.

Background

Concrete is a material which is necessary in the industry such as construction at present. When the concrete is subjected to natural environment change, expansion and shrinkage phenomena can be generated, and the wall body is cracked due to the expansion and shrinkage of the concrete.

The concrete test block is typically tested for expansion and shrinkage in the laboratory using a concrete shrinkage test apparatus. Specifically, a dial indicator is generally adopted, and the shrinkage of the concrete block is accurately calculated in a form of multiple measurements.

The prior art device is generally dedicated to diversity and accuracy of measuring results, for example, chinese patent grant publication No. CN213843272U discloses a concrete shrinkage experimental device, it utilizes limiting plate to drive the concrete block and moves, utilize the second backup plate to drive the dial indicator and move, replace manual form reduction error through screw drive, for example, chinese patent grant publication No. CN218272064U discloses a concrete shrinkage experimental device, it is through changing the inclination that sets up in concrete block both sides side support arm for it can carry out spacingly to the concrete block of different shapes, for example, chinese patent grant publication No. CN215931884U discloses a concrete shrinkage experimental device, it sets up the clamp plate above the concrete block, and set up measuring mechanism on the clamp plate in a matched manner, utilize clamp plate displacement to obtain the shrinkage factor of concrete block in vertical direction.

In the practical use process, we find that the prior art device only bears the concrete block in the practical use process, the essence is still that the concrete block is respectively fixed by the concrete block and the dial indicator, the shrinkage of the concrete block is calculated by using the difference value measured by the dial indicator (the difference value between the interval between the concrete block and the dial indicator before shrinkage, the interval between the concrete block and the dial indicator), and the concrete block shrinkage test device which can not meet the aim that the concrete block shrinkage device intuitively, accurately, time-saving and labor-saving detects the concrete block shrinkage rate is considered to be needed, and the time-saving and labor-saving concrete block shrinkage test device which can intuitively reflect the concrete block shrinkage value in the detection process is considered to be needed.

Disclosure of Invention

Aiming at the defects in the prior art, the utility model provides a concrete shrinkage test device which has the advantages of intuitively reflecting the shrinkage of concrete and saving time and labor in the detection process, and solves the defects that the device in the prior art can not optimize the detection process, saves labor and can only fix concrete blocks.

In order to achieve the above purpose, the present utility model adopts the following technical scheme:

the utility model provides a concrete shrinkage test device, includes the bottom plate, bottom plate upper end left and right sides is provided with an instruction board respectively, instruction board and bottom plate sliding connection are provided with supporting platform between two instruction boards, and the concrete piece of waiting to detect is placed on supporting platform, and two instruction board lower extreme from left to right runs through and is provided with the internal thread hole to internal thread hole spiro union has two-way screw rod, one of them end of two-way screw rod is provided with gear drive mechanism, gear drive mechanism is including the cover and locates the outer driven gear of two-way screw rod, driven gear quantity is a plurality of, and single driven gear one side is provided with the driving gear, and driven gear and corresponding driving gear looks adaptation and intermeshing, the transmission ratio between a plurality of driven gears and the corresponding driving gear is inequality, central point puts and is provided with the amesdial on the instruction board.

Preferably, the pilot board lower extreme runs through from left to right and is provided with mounting groove I, sliding connection has a collar I in the mounting groove I, the internal thread hole sets up in collar I inboard, collar I up end height is less than the terminal surface height under the concrete block that waits to detect.

Preferably, the left and right sides of the lower end of the indication board are respectively fixedly connected with a connecting plate, the lower end of the connecting plate is provided with a U-shaped groove, the U-shaped opening of the U-shaped groove faces downwards, the U-shaped groove is rotationally connected with a rolling wheel, and the bottom plate is provided with a sliding groove I aiming at the connecting plate and the rolling wheel.

Preferably, a plurality of resistance blocks are arranged in the mounting groove I, the resistance blocks are in interference fit with the mounting ring I, the resistance blocks are hemispheres, a sliding groove II is formed in the mounting ring I from left to right in a penetrating mode through the resistance blocks, and the resistance blocks are embedded into the sliding groove II.

Preferably, the pilot board intermediate position runs through from left to right and is provided with mounting groove II, sliding connection has collar II in the mounting groove II, be provided with a plurality of breach grooves on the collar II, breach groove is open structure relatively far away from collar II one end, and a plurality of breach grooves encircle collar II central axis and evenly arrange, a compression spring of fixedly connected with in the breach inslot, compression spring is close to pilot board one end fixedly connected with stopper I relatively, be provided with spacing groove I to stopper I in the pilot board, stopper I is semi-ellipsoid.

Preferably, the inside fixedly connected with resistance ring of collar II, resistance ring and amesdial damping connection.

Preferably, the lower end of the single indicating plate is provided with two mounting grooves I, and a driving gear is arranged between two corresponding driven gears on two bidirectional screws which are in threaded connection with the lower end of the single indicating plate.

Preferably, a plurality of driving gears are evenly arranged from left to right, a rotating groove is formed in the single driven gear in a penetrating mode from left to right, a sliding rod is connected in the rotating groove in a sliding mode, a rotating wheel is fixedly connected to one end, far away from the indicating plate, of the sliding rod, a plurality of limiting blocks II are fixedly connected to one end, relatively close to the indicating plate, of the sliding rod, and a limiting groove II is formed in the single driven gear in a penetrating mode from left to right to the limiting blocks II.

Compared with the prior art, the utility model has the following beneficial effects:

according to the utility model, the concrete blocks are detected by using the two left and right indicating plates, the indicating plates can be closely attached to the concrete blocks by moving the indicating plates, at the moment, when the concrete blocks shrink along with the change of time, the shrinkage length of the concrete blocks can be intuitively reflected by observing the gap between the concrete blocks and the indicating plates, and the user can be helped to quickly obtain rough concrete shrinkage rate data, so that the user can roughly judge the properties of the concrete blocks, and is convenient for the user to quickly compare a plurality of concrete properties to be detected.

According to the utility model, the two indicating plates can be quickly attached to the concrete block through the bidirectional screw, and meanwhile, the bidirectional screw can directly control the relative distance between the two indicating plates, so that the two indicating plates can be used for restraining the position of the concrete block when attaching to the concrete block, and the two supporting rods on the supporting platform can be symmetrically arranged along the central line of the concrete block, thereby ensuring that the whole concrete block is balanced in stress and avoiding uneven shrinkage deformation caused by uneven stress.

Drawings

FIG. 1 is a schematic diagram of the overall structure of the present utility model;

FIG. 2 is a schematic diagram of the overall structure of the gear drive mechanism of the present utility model;

fig. 3 is a schematic diagram showing the connection of the limiting block I and the compression spring.

In the figure: 1. a bottom plate; 2. a support platform; 3. an indication board; 4. a mounting groove II; 5. a dial gauge; 6. a connecting plate; 7, preparing a base material; a rolling wheel; 8. a chute I; 9. a mounting ring I; 10. a bidirectional screw; 11. a resistance ring; 12. a mounting ring II; 13. a chute II; 14. a resistance block; 15. a limiting block II; 16. a driven gear; 17. a drive gear; 18. a slide bar; 19. a rotating wheel; 20. a limit groove II; 21. a limiting block I; 22. compressing the spring.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the present utility model, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the present utility model and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

Referring to fig. 1-3, a concrete shrinkage test apparatus includes a base plate 1, and a support platform 2 is disposed on the base plate 1 to support a concrete block.

Specifically, the supporting platform 2 comprises supporting rods, the upper ends of which are directly contacted with the concrete blocks, and the number of the supporting rods is two so as to avoid uneven shrinkage deformation caused by unbalanced stress of the concrete blocks.

The bottom plate 1 left and right sides is provided with an indicating plate 3 respectively, indicating plate 3 and bottom plate 1 sliding connection, indicating plate 3 is for bottom plate 1 about rectilinear motion, can change the relative distance between indicating plate 3 and the supporting platform 2 through sliding indicating plate 3, thereby make in practice indicating plate 3 can press close to the concrete piece, this device is through setting up indicating plate 3, and make indicating plate 3 press close to the concrete piece, make when the concrete piece shrink, will have certain clearance between concrete piece and the indicating plate 3, the user accessible indicates the clearance between 3 and the concrete piece and directly perceivedly judges concrete piece shrinkage ratio, help user obtain rough concrete shrinkage ratio data fast, make the user can roughly make the judgement to concrete piece nature.

Specifically, the lower end of the indication board 3 is screwed with a screw, and in practice, the indication board 3 is limited by the bottom board 1 so that the indication board 3 cannot be twisted, and at this time, the relative position between the indication board 3 and the bottom board 1 can be changed when the screw is rotated by using threaded connection.

The screw rod is two-way screw rod 10 to single two-way screw rod 10 axial both ends respectively with two instruction board 3 spiro union, utilize the characteristic that two-way screw rod 10 both ends screw thread direction is opposite, make can make two instruction boards 3 be close to each other or keep away from each other when rotating two-way screw rod 10, this action can quick change interval between two instruction boards 3, can also retrain concrete block position, make two bracing pieces on supporting platform 2 can set up with concrete block central line symmetry, thereby make the whole atress of concrete block balanced, avoid causing shrinkage deformation inhomogeneous because of the atress is uneven.

Specifically, the indicating plate 3 lower extreme is provided with collar I9, and collar I9 runs through from left to right and is provided with the internal thread hole, and collar I9 passes through internal thread hole and two-way screw rod 10 one end spiro union.

Still further, the mounting groove I is formed in the lower end of the indicating plate 3 in a penetrating mode from left to right, the mounting ring I9 is embedded into the mounting groove I and is in sliding connection with the indicating plate 3, in practice, the mounting ring I9 is in threaded connection with the bidirectional screw 10, the bidirectional screw 10 drives the mounting ring I9 to do left-right straight-line cloud in the process of rotating the bidirectional screw 10, at the moment, the mounting groove I exists, the mounting ring I9 can be separated from the indicating plate 3, namely, in practice, when the indicating plate 3 is tightly attached to a concrete block, and the reaction force exerted on the indicating plate 3 by the concrete block is larger than the friction resistance between the mounting ring I9 and the indicating plate 3, the two mounting rings I9 can continuously move in opposite directions, but at the moment, the indicating plate 3 can not do left-right straight-line movement relative to the bottom plate 1, and the fact that the indicating plate 3 exerts excessive compaction force on the concrete block is prevented from influencing the shrinkage of the concrete block on the premise of guaranteeing the tight attachment of the indicating plate 3 and the concrete block is guaranteed.

Specifically, the connecting plate 6 is fixedly connected with respectively in the left and right sides of the lower extreme of the indicating plate 3, the lower extreme of the connecting plate 6 is provided with a U-shaped groove, and the U-shaped opening of the U-shaped groove is downward, the U-shaped groove is rotationally connected with the rolling wheel 7, the chute I8 is arranged on the bottom plate 1 aiming at the connecting plate 6 and the rolling wheel 7, the resistance of the indicating plate 3 in the process of doing left and right rectilinear motion relative to the bottom plate 1 can be greatly reduced on the premise of supporting the indicating plate 3 by utilizing the chute I8 and the rolling wheel 7, only small force is needed between the installation ring I9 and the indicating plate 3, and the installation ring I9 can drive the indicating plate 3 to do left and right rectilinear motion relative to the bottom plate 1.

Specifically, a plurality of resistance blocks 14 are arranged in the mounting groove I, and the resistance blocks 14 are in interference fit with the mounting ring I9, so that the pressing force applied to the mounting ring I9 by the resistance ring 11 is utilized to improve the force between the remaining indicating plates 3 of the mounting ring I9, and the mounting ring I9 can drive the indicating plates 3 to do left-right linear motion relative to the bottom plate 1.

Still further, the resistance block 14 is a hemisphere to reduce the contact area between the resistance block 14 and the mounting ring i 9, reduce the dynamic friction force between the resistance block 14 and the mounting ring i 9, in practice, the device utilizes the hemispherical structural feature of the resistance block 14, so that the mounting ring i 9 can drive the indicator plate 3 in the initial state, push the concrete block to enable the two indicator plates 3 to be tightly attached to the concrete block at the same time, when the concrete block is tightly attached to the two indicator plates 3, it can be ensured that the two support rods on the support platform 2 can be symmetrically arranged with the center line of the concrete block, at this time, when the mounting ring i 9 continues to drive the indicator plates 3, so that when the two indicator plates 3 have a trend of moving in opposite directions, the reactive force exerted on the indicator plates 3 by the concrete block is gradually increased, and when the reactive force is greater than the static friction force exerted on the mounting ring i 9 by the resistance block 14, the relative sliding occurs between the mounting ring i 9 and the indicator plates 3. Specifically, this device utilizes interference fit between resistance piece 14 and the collar I9, resistance piece 14 is the hemisphere so that resistance piece 14 applys static friction force on collar I9 great, dynamic friction force is less, this action can guarantee that indicator board 3 is to the position adjustment function of concrete piece, guarantee indicator board 3 closely laminating concrete piece, can also avoid indicator board 3 to last (when indicator board 3 begins to slide, because static friction force is less, then the pressure that indicator board 3 applyed on the concrete piece will reduce or even disappear) exert pressure to the concrete piece, influence concrete piece shrinkage factor accuracy.

Specifically, the sliding groove II 13 is formed in the mounting ring I9 in a penetrating manner from left to right in relation to the resistance block 14, the resistance block 14 is embedded into the sliding groove II 13, the resistance block 14 and the sliding groove II 13 are mutually matched to limit the mounting ring I9, and the mounting ring I9 is prevented from rotating under the driving of the bidirectional screw 10.

Two ends of the bidirectional screw rod 10 are respectively connected with the bottom plate 1 through a supporting frame, the bidirectional screw rod 10 is rotationally connected with the supporting frame, and the supporting frame is fixedly connected with the bottom plate 1 so as to ensure that the bidirectional screw rod 10 can only rotate relative to the bottom plate 1 and cannot be separated from the bottom plate 1.

One end of the bidirectional screw 10 is provided with a gear driving mechanism to drive the bidirectional screw 10 to rotate.

Specifically, the gear driving mechanism comprises a driven gear 16 sleeved outside the bidirectional screw 10, a driving gear 17 is arranged on one side of the driven gear 16, and the driving gear 17 is matched with the driven gear 16 and meshed with the driven gear 16, so that the driven gear 16 can be driven by the driving gear 17, and the bidirectional screw 10 is driven to rotate.

Further, the number of the driven gears 16 is plural, one driving gear 17 is correspondingly arranged on the single driven gear 16, and when the transmission ratio between the driven gears 16 and the corresponding driving gears 17 is unequal, so that different driving gears 17 rotate for the same number of turns, the rotation amplitude of the corresponding driven gears 16, namely the bidirectional screw 10, is unequal, which can help a user to precisely move the indication board 3, so that the user can slightly move the indication board 3 to enable the indication board 3 to be attached to the concrete block slowly.

Furthermore, two mounting grooves I are formed in the lower end of the single indicating plate 3, a driving gear 17 is arranged between two corresponding driven gears 16 on two bidirectional screws 10 in threaded connection with the lower end of the single indicating plate 3, the two bidirectional screws 10 are arranged at the lower end of the single indicating plate 3, the indicating plate 3 can be further limited, the indicating plate 3 can be kept in a vertical state, and the indicating plate 3 can be driven by a mounting ring I9 to do left-right rectilinear motion relative to the bottom plate 1.

Specifically, the plurality of driving gears 17 located between the two bidirectional screws 10 are uniformly arranged from left to right.

The single driven gear 16 is provided with a rotating groove in a penetrating manner from left to right, the sliding groove is connected with a sliding rod 18 in a sliding manner, one end, which is relatively far away from the indication board 3, of the sliding rod 18 is fixedly connected with a rotating wheel 19 so as to facilitate the rotation of the sliding rod 18 by a user, one end, which is relatively close to the indication board 3, of the sliding rod 18 is fixedly connected with a plurality of limiting blocks II 15, the limiting blocks II 15 are provided with limiting grooves II 20 in a penetrating manner from left to right on the single driven gear 16, the corresponding driving gear 17 is driven to rotate by the aid of the limiting blocks II 15 and the limiting grooves II 20 through the rotating sliding rod 18 in a mutually matched manner in practice, the limiting grooves II 20 penetrate through the corresponding driven gear 16 from left to right, the corresponding position of the limiting blocks II 15 is changed through the left and right sliding rod 18, and the corresponding driving gear 17 is convenient for the user to rotate.

Specifically, the bottom plate 1 supports the slide bar 18 through the L-shaped support frame, so that the slide bar 18 can only do left-right rectilinear motion relative to the bottom plate 1 and rotate relative to the bottom plate 1, but cannot be separated from the bottom plate 1.

The dial indicator 5 is arranged at the center of the indication plate 3, and the shrinkage value of the concrete block can be accurately measured by using the dial indicator 5.

Specifically, the intermediate position of the indicating plate 3 is provided with a mounting groove II 4 in a penetrating manner from left to right, a mounting ring II 12 is connected in a sliding manner in the mounting groove II 4, and the dial indicator 5 is positioned in the mounting ring II 12.

Furthermore, a plurality of notch grooves are formed in the mounting ring II 12, and the notch grooves are uniformly distributed around the central axis of the mounting ring II 12.

The notch groove is relatively far away from one end of the mounting ring II 12 and is of an open structure, a compression spring 22 is fixedly connected in the notch groove, the compression spring 22 is relatively close to the indicating plate 3 and is fixedly connected with a limiting block I21, and under the action of the compression spring 22, when the limiting block I21 is not affected by external force, the limiting block I21 should protrude out of the notch groove.

Be provided with corresponding spacing groove I to stopper I21 in the instruction board 3, utilize stopper I21 and spacing groove I mutually support can retrain collar II 12 position fast, thereby the user can dismantle collar II 12 from instruction board 3 in practice and realize freeing dial indicator 5 for this device can place properly in with fixed position, and dial indicator 5 can dismantle therefrom and be used for other measurement processes, can retrain collar II 12 position through stopper I21 and spacing groove I mutually support in the dismantlement installation, make the surplus instruction board 3 relative position of collar II 12 can satisfy the demand fast.

The stopper I21 is semi-ellipsoid to make when the user applys pressure to stopper I21 level, promptly to the dismantlement process of collar II 12, the arcwall face of stopper I21 can become the thrust of vertical direction with the pressure on the horizontal direction, forces stopper I21 to sink into the breach inslot, can realize the dismantlement of collar II 12 this moment, when the installation to collar II 12, the arcwall face of stopper I21 can make stopper I21 can get into the spacing inslot I automatically and realize relative fixation.

The inboard fixedly connected with resistance ring 11 of collar II 12, thereby resistance ring 11 and amesdial 5 damping connection further make the amesdial 5 can separate between and collar II 12, further liberate amesdial 5 to be convenient for change amesdial 5.

Working principle: in the actual use process, firstly, a concrete block is required to be placed on the supporting platform 2, the two supporting rods are ensured to be in contact with the lower end face of the concrete block, then the sliding rod 18 is moved to select the combination of the driving gear 17 and the driven gear 16 with the largest transmission ratio, the rotating wheel 19 is rotated, the two indicating plates 3 are rapidly moved to rapidly reduce the distance between the two indicating plates 3, then the indicating plates 3 can push the concrete block in the process to enable the concrete block to be placed regularly (the side edge of the length direction of the concrete block is perpendicular to the indicating plates 3), the indicating plates 3 can push the concrete block to enable the two supporting rods on the supporting platform 2 to be symmetrically arranged on the center line of the concrete block, when the indicating plates 3 are slid to enable the indicating plates 3 to be close to the concrete block, the relative position of the sliding rod 18 is changed, the corresponding combination of the driving gear 17 and the driven gear 16 is sequentially selected according to the sequence from the large transmission ratio to the small transmission ratio, the position of the indicating plates 3 is further finely adjusted to enable the indicating plates 3 to be attached to the concrete block, finally, the device is placed properly, after a period of time, the setting gauge 5 is properly, and the concrete block is accurately installed, and the shrinkage quantity is measured.

Although embodiments of the present utility model have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents.

Claims (8)

1. A concrete shrinkage test device is characterized in that: the concrete block detection device comprises a bottom plate (1), wherein an indication plate (3) is respectively arranged on the left side and the right side of the upper end of the bottom plate (1), the indication plate (3) is in sliding connection with the bottom plate (1), a supporting platform (2) is arranged between the two indication plates (3), and a concrete block to be detected is placed on the supporting platform (2);

the lower ends of the two indicating plates (3) are provided with internal threaded holes in a penetrating way from left to right, and a bidirectional screw rod (10) is screwed in the corresponding internal threaded holes at the lower ends of the two indicating plates (3);

one end of the bidirectional screw rod (10) is provided with a gear driving mechanism, the gear driving mechanism comprises a plurality of driven gears (16) sleeved outside the bidirectional screw rod (10), one side of each driven gear (16) is provided with a driving gear (17), the driven gears (16) are matched with and meshed with the corresponding driving gears (17), and the transmission ratios between the driven gears (16) and the corresponding driving gears (17) are unequal;

and a dial indicator (5) is arranged at the central position on the indication plate (3).

2. A concrete shrinkage test apparatus according to claim 1, wherein: the lower end of the indication plate (3) is provided with a mounting groove I in a penetrating manner from left to right, a mounting ring I (9) is connected in a sliding manner in the mounting groove I, and the inner threaded hole is formed in the inner side of the mounting ring I (9);

the height of the upper end face of the mounting ring I (9) is smaller than that of the lower end face of the concrete block to be detected.

3. A concrete shrinkage test apparatus according to claim 2, wherein: the left side and the right side of the lower end of the indication plate (3) are fixedly connected with a connecting plate (6) respectively, a U-shaped groove is formed in the lower end of the connecting plate (6), a U-shaped opening of the U-shaped groove faces downwards, and a rolling wheel (7) is rotationally connected in the U-shaped groove;

a chute I (8) is arranged on the bottom plate (1) and aims at the connecting plate (6) and the rolling wheel (7).

4. A concrete shrinkage test apparatus according to claim 3, wherein: a plurality of resistance blocks (14) are arranged in the mounting groove I, the resistance blocks (14) are in interference fit with the mounting ring I (9), and the resistance blocks (14) are hemispheres;

a sliding groove II (13) is formed in the mounting ring I (9) in a penetrating mode from left to right aiming at the resistance block (14), and the resistance block (14) is embedded into the sliding groove II (13).

5. A concrete shrinkage test apparatus according to claim 1, wherein: the middle position of the indication plate (3) is provided with a mounting groove II (4) in a penetrating manner from left to right, a mounting ring II (12) is connected in a sliding manner in the mounting groove II (4), a plurality of notch grooves are formed in the mounting ring II (12), one end, which is relatively far away from the mounting ring II (12), of the notch grooves is of an open structure, and the notch grooves are uniformly distributed around the central axis of the mounting ring II (12);

a compression spring (22) is fixedly connected in the notch groove, one end, relatively close to the indication plate (3), of the compression spring (22) is fixedly connected with a limiting block I (21), and a limiting groove I is formed in the indication plate (3) and aims at the limiting block I (21);

the limiting block I (21) is a semi-ellipsoid.

6. The concrete shrinkage test apparatus according to claim 5, wherein: the inner side of the mounting ring II (12) is fixedly connected with a resistance ring (11), and the resistance ring (11) is in damping connection with the dial indicator (5).

7. A concrete shrinkage test apparatus according to claim 1, wherein: two mounting grooves I are formed in the lower end of the single indication plate (3), and a driving gear (17) is arranged between two corresponding driven gears (16) on two bidirectional screws (10) which are in threaded connection with the lower end of the single indication plate (3).

8. The concrete shrinkage test apparatus according to claim 7, wherein: a plurality of driving gears (17) are uniformly distributed from left to right, a single driven gear (16) is provided with a rotating groove in a penetrating manner from left to right, and a sliding rod (18) is connected in the rotating groove in a sliding manner;

the sliding rod (18) is kept away from indicator board (3) one end fixedly connected with rotor (19) relatively, a plurality of stopper II (15) are connected with to indicator board (3) one end fixedly connected with relatively to sliding rod (18), run through from left to right to stopper II (15) on single driven gear (16) and are provided with spacing groove II (20).