CN204718888U - A kind of regeneration concrete TERM DEFORMATION test loads and measurement mechanism - Google Patents

Abstract

The utility model discloses a loading and measuring device for a long-term deformation test of recycled concrete, which comprises a special-shaped bearing platform. Two positioning columns that can slide horizontally relative to the special-shaped bearing platform are arranged above the special-shaped bearing platform. A component is jointly supported above the positioning columns, and a loading device is arranged above the component; a plurality of position-adjustable dial gauges are arranged between the two positioning columns. The utility model can load different positions of the components according to different loading requirements, and realize three-point loading or partial loading, thereby improving the application range of the loading and measuring device; the total weight of the counterweight can be enlarged to a certain extent by using the principle of leverage. The multiple is applied to the component to be tested, and the whole device forms a self-balancing system to ensure that the load of the component is constant under long-term load. The operation method is convenient and feasible, making the measurement result closer to the actual situation, and the conclusion drawn is more convincing.

Description

A loading and measuring device for long-term deformation test of recycled concrete

technical field

The utility model relates to a loading and measuring device, in particular to a loading and measuring device for a long-term deformation test of recycled concrete.

Background technique

The timely introduction of recycled concrete not only solves the problem of huge amount of construction waste disposal, but also enables the recycling of construction waste to produce construction raw materials, which not only saves a lot of natural resources, but also reduces the energy consumption of production. Therefore, this environmentally friendly building material and related technical research has become a hot spot in the development of civil engineering building materials. Due to the micropores and microcracks of the cement gel on the surface of the recycled coarse aggregate in recycled concrete, the recycled concrete beam has a long-term stability. Under the action of constant load, the deflection change is different from that of ordinary concrete beams, but there are few domestic studies on this aspect, and the deflection change has a very important impact on the long-term performance and durability of recycled concrete beams. Therefore, recycled concrete It is particularly important to measure the deflection of a beam under a long-term constant load.

At present, there are several common measurement methods for measuring the deflection of recycled concrete beams under long-term constant load, such as jack pressure method, large spring force method and direct stacking method of heavy objects. For the jack pressurization method, due to the limitation of the jack's own structure, the phenomenon of "oil return" is prone to occur during the long-term pressurization process, and when the deflection of the component changes, the support distance of the jack becomes longer, causing the pressure value of the jack to change. , which cannot meet the key requirement of constant load of components under long-term load. For the large spring force method, since the deflection of the component changes, the length of the large spring changes, so the load applied to the component cannot be guaranteed to remain constant. For the direct accumulation method of heavy objects, in order to achieve a huge pressure value, the density of the accumulated heavy objects is very high, and the requirements for the test site are very strict. The implementation process is very difficult, and the loading method is not flexible. These objects bring many problems such as great safety hazards to the measurement process of components.

Contents of the invention

In view of the above-mentioned problems or defects in the prior art, the purpose of the present utility model is to provide a loading and measuring device for constant load deformation test of recycled concrete.

In order to achieve the above object, the utility model adopts the following technical solutions:

A loading and measuring device for a long-term deformation test of recycled concrete, comprising a special-shaped cap, two positioning columns that can slide horizontally relative to the special-shaped cap are arranged on the top of the special-shaped cap, and the tops of the two positioning columns are in common supporting a component, and a loading device is arranged above the component;

A plurality of position-adjustable dial gauges are arranged between the two positioning columns.

Further, a sliding groove is provided on the special-shaped platform along its width direction, and the positioning column can slide along the sliding groove.

Specifically, the loading device includes a steel beam arranged horizontally and perpendicular to the member, one end of the steel beam is connected to the special-shaped platform through a vertically arranged steel arm, and the steel beam is movably connected to the steel arm; A loading platform is installed below the other end of the beam.

Further, a distribution beam is provided between the steel beam and the component; a circular shaft support and a triangular support are provided between the distribution beam and the component, and the circular shaft support and the triangular support are about the center of the distribution beam. The position is symmetrically set.

Specifically, a plurality of supports are arranged between the two positioning posts, and the supports can slide along the slide groove, and the dial indicator is installed on the supports.

Further, a triangular support is provided between the positioning column and the component.

Optionally, the steel beam and the steel arm are connected by pins.

Optionally, the special-shaped platform is a symmetrical polygon.

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

1. Set the positioning column to support the upper component, and its position can be adjusted according to the size of different components, so that the two positioning columns are respectively located below the two ends of the component to support the component; adjust the position of the positioning column and the component as a whole, so that the loading device According to different loading requirements, different positions of the components can be loaded to realize three-point loading or partial loading, thereby improving the application range of loading and measuring devices.

2. The loading device is set up, and the total weight of the counterweight can be amplified by a certain multiple and applied to the component to be tested by using the principle of leverage. The whole device forms a self-balancing system to ensure that the load of the component is constant under long-term load, and the operation method is convenient. It is feasible, making the measurement results closer to the actual situation, and the conclusions drawn are more convincing; it greatly improves the accuracy and convenience of the deflection measurement of recycled concrete components under long-term loads, and overcomes the difficult operation and poor precision of existing methods Defects.

3. Set up multiple supports so that the position of the dial indicator can be adjusted according to the point to be measured, so that the location of the measuring point can be arranged flexibly, and it is convenient to cooperate with different loading positions of the component, which can meet the measurement requirements of the deflection value at different positions of the component and improve measurement flexibility.

4. Set the special-shaped caps as special-shaped reinforced concrete caps with multilateral connections to ensure that the positioning column has a long enough moving distance on the special-shaped caps, so that the positioning columns can support components of different sizes; and the special-shaped caps are along the length of the steel beam. The direction part is extended, so that the special-shaped bearing platform can bear the bending moment brought by the loading process, and ensure the stability of the entire experimental device.

Description of drawings

Fig. 1 is the front view of the utility model;

Fig. 2 is the top view of the utility model;

Fig. 3 is a side view of the utility model;

The symbols in the figure represent: 1—steel rib, 2—hook, 3—loading platform, 4—steel beam, 5—member, 6—special-shaped cap, 7—smooth round steel bar, 8—positioning column, 9—steel arm, 10—chute, 11—distribution beam, 12—circular shaft support, 13—triangular support, 14—support, 15—support clamp, 16—diagonal indicator, 17—triangular support. the

The scheme of the utility model is further explained and described in detail below in conjunction with the accompanying drawings and specific embodiments.

Detailed ways

According to the above-mentioned technical scheme, referring to Fig. 1-3, the long-term deformation test loading and measuring device of recycled concrete of the present utility model includes a special-shaped cap 6, and two above the special-shaped cap 6 are arranged to be able to move relative to the special-shaped cap 6. The positioning column 8 sliding in the horizontal direction, a component 5 is jointly supported above the two positioning columns 8, and a loading device is arranged above the component 5; multiple positions can be arranged between the two positioning columns 8 Tune the dial indicator 16.

The member 5 is a strip-shaped concrete beam whose length direction is parallel to the line connecting the two positioning columns 8 .

The loading device is used to apply pressure to the component 5; the two positioning columns 8 are used to support the upper component 5, and its position can be adjusted according to the size of different components 5, so that the two positioning columns 8 are respectively located on both sides of the component 5. The bottom of the end is to support the member 5.

When the relative positions of the two positioning columns 8 and the component 5 are fixed, the overall position of the positioning column 8 and the component 5 can be adjusted, so that the loading device can load different positions of the component 5 according to different loading requirements, and realize three-point loading Or partial loading, thereby improving the range of use of loading and measuring devices.

The dial indicator 16 is used to measure the deflection value of the member 5, and the position of the dial indicator 16 can be adjusted according to the point to be measured, so that the location of the measuring point can be arranged flexibly, and it is convenient to cooperate with different loading positions of the member 5, and can meet the needs of different positions of the member. The measurement requirement of deflection value improves the flexibility of measurement.

Specifically, a sliding groove 10 is provided on the special-shaped bearing platform 6 along its width direction, and the positioning column 8 can slide along the sliding groove 10, and there are two sliding grooves 10 arranged in parallel. The cross-sectional area of the chute 10 on the special-shaped bearing platform 6 is 20mm×20mm, and the length is 2200mm. Made of steel. The positioning column 8 slides along the chute 10, so that the distance between the two positioning columns 8 can be changed flexibly and the operation is convenient.

Specifically, the loading device includes a steel beam 4 arranged horizontally and perpendicular to the member 5, one end of the steel beam 4 is connected to the special-shaped platform 6 through a vertically arranged steel arm 9, and the steel beam 4 and the steel arm 9 Movable connection; the loading platform 3 is installed under the other end of the steel beam 4 . The longitudinal section of the steel beam 4 is I-shaped.

A hook 2 is installed under one end of the steel beam 4, and a loading platform 3 is hung on the hook 2, and different counterweights are placed on the loading platform 3 as required.

Optionally, a distribution beam 11 is provided between the steel beam 4 and the component 5, and a circular shaft support 12 and a triangular support 17 are provided between the distribution beam 11 and the component 5, and the circular shaft support 12 and triangular support 17 are arranged symmetrically about the middle position of distribution beam 11. The steel beam 4 divides the resultant force into component forces of equal magnitude through the distribution beam 11 , the circular shaft support 12 and the triangular support 17 to load the member 5 . the

The circular shaft support 12 and the triangular support 17 jointly form a simple support for the distribution beam 11, so that the vertical load borne by the distribution beam 11 is equally divided and vertically transmitted downward.

Further, the middle position of the distribution beam 11 is located directly above the middle position of the member 5, and the circular shaft support 12 and the triangular support 17 are respectively located directly above the three-point position of the member 5, ensuring that the steel The beam 4 carries out three-point loading on the member 5 .

Further, a steel rib 1 is provided inside the steel beam 4 where the force is applied to the component 5 to ensure the rigidity of the steel beam 4 ; a steel rib 1 is provided inside the distribution beam 11 to ensure the rigidity of the distribution beam 11 .

Further, a plurality of supports 14 are arranged between the two positioning posts 8 , and the supports 14 can slide along the slide groove 10 , and the dial indicator 16 is installed on the supports 14 . The support 14 fixes the dial indicator 16 through the support clamp 15, and adjusts the position of the dial indicator 16 by adjusting the position of the support 14.

Optionally, there are three supports 14 and three corresponding dial indicators 16. By adjusting the position of the supports 14, the dial indicator 16 in the middle position is at the middle position of the member 5. Directly below, the remaining two dial gauges 16 are respectively located directly below the stress point of the component 5 .

Further, a triangular support 13 is provided between the positioning column 8 and the member 5 . The arrangement of the triangular support 13 facilitates accurate determination of the force-bearing position of the component 5 . the

Further, the steel beam 4 and the steel arm 9 are connected by pins, so that the steel beam 4 can rotate relative to the steel arm 9 , so that the component 5 and the distribution beam 11 can be placed under the steel beam 4 .

Specifically, two smooth round steel bars 7 are arranged on the bottom surface of the positioning column 8 along the length direction of the chute 10 , and the smooth round steel bars 7 can slide along the chute 10 .

The size of the positioning column 8 is 400mm * 400mm * 450mm, and its manufacturing process is as follows: adopt four models to be φ 10, and the threaded steel bars that length is 450mm are distributed vertically in a diamond shape, and the bottom ends of the above-mentioned steel bars are welded to the size by pressure welding. On the steel plate of 400mm×400mm×10mm, form the formwork along the edge of the steel plate, the height of the formwork is 450mm, and then pour concrete into the formwork to form it; finally, weld two models of φ20, the length is the light round steel bar of 400mm, and the light round steel bar 7 is placed in the chute 10 to ensure that the positioning column 8 can slide along the chute 10.

Specifically, two smooth round steel bars 7 are arranged on the bottom surface of the support 14 along the length direction of the chute 10 , and the smooth round steel bars 7 can slide along the chute 10 .

The manufacturing method of the support 14 is as follows: a smooth round steel bar with a model number of φ10 and a length of 350mm is welded vertically to the center of a steel plate with a size of 400mm×50mm×10mm, and two model steel bars are welded along the direction of the chute at the bottom of the steel plate. Be φ 20, length is the smooth round steel bar of 50mm, smooth round steel bar is placed in the chute 10 and guarantees that bearing 14 can slide along chute 10.

The bottom surface of the special-shaped cap 6 is provided with a plurality of bending-resistant steel bars, which are criss-crossed and distributed in a net shape. The bending-resistant steel bars are used to bear the huge load on the special-shaped cap 6 during the loading The internal force of the bending moment ensures the normal operation of the special-shaped cap 6.

The special-shaped bearing platform 6 is a symmetrical polygon. Optionally, it is provided with 10 sides, respectively a1-a10. Referring to FIG. 3, the chute 10 is set on the connection between the sides a3 and a9 to ensure The positioning column 8 has a long enough moving distance on the special-shaped platform 6, so that the positioning column 8 can support members 5 of different sizes; the part of the special-shaped platform 6 surrounded by the sides a5, a6 and a7 makes the special-shaped platform 6 is extended along the length direction of the steel beam 4, so that the special-shaped cap 6 can withstand the bending moment brought by the loading process, and ensure the stability of the entire experimental device.

The unilateral dimensions of the special-shaped caps 6 are respectively 400mm×1000mm×400mm×1000mm×600mm×400mm×600mm×1000mm×400mm×1000mm, which are multi-sided connected special-shaped reinforced concrete caps, which are convenient for formwork production and meet the requirements of Measurement requirements while saving a lot of space.

The overall height of the device of the present utility model is 1800mm, the widest part width is 2200mm, the narrowest part is 400mm, and the length is 3300mm.

The loading and measuring device for the constant load deformation test of recycled concrete of the present invention, the specific realization process is as follows:

(1) According to the requirements of "Test Method for Long-term Performance and Durability of Ordinary Concrete", three dimensions are made, all of which are 400mm×400mm×2000mm. The concrete used for the specimens is ordinary concrete with 0%, 50%, and 100% replacement rate of recycled coarse aggregate and recycled concrete. After pouring the three specimens, put them into the standard curing room for 28 days and then start the long-term loading test.

(2) Add lubricating oil with a depth of 5mm to the chute 10 on the special-shaped cap 6, push the two positioning columns 8 to make the inner distance 1600mm, and move the component 5 to the positioning column 8.

(3) Put the three supports 14 into the chute 10 in turn, the first support 14 is placed directly below the center of the member 5, the second support 14 and the third support 14 are respectively placed on the two sides of the member 5. Directly below the power point, three dial gauges 16 are placed on the bearing 14 respectively, and are fixed with the bearing clamp 15.

(4) Press the steel beam 4 on the distribution beam 11 to divide the resultant force into two equal-sized component forces and carry out three-point loading on the component 5, then load the counterweight on the loading platform 3, in order to prevent the counterweight from During the long-term test, the loading value changes due to water absorption, and the concrete blocks that have been discarded for more than 2 years are re-weighed and calibrated as the loading counterweight. Refer to the requirements of GB50152-92 in the "Standards for Test Methods of Concrete Structures". During the test, preload is carried out first. The preload is divided into three levels. The loading value of each level is 5% of the estimated total loading value. After the equipment is debugged normally, it is unloaded and then reloaded in different stages. When the bending crack width of the component reaches the range of 0.2mm, the loading is stopped and the loading is kept unchanged. At this time, the component is considered to be in the limit state of normal service and is subjected to long-term sustained load. The total weights of the counterweights added to the three components to be tested are G ₁ =1000kg, G ₂ =930kg, and G ₃ =850kg.

See formula 1:

F _combined ＝G×(L ₂ ÷ L ₁ ) Formula 1

F represents the resultant force on _the component; G represents the weight of the added counterweight; L ₂ represents the distance between the force application point of the steel beam 4 and the loading platform 3; L ₁ represents the distance between the force application point of the steel beam 4 and the steel arm 9 distance between.

In this test, L ₂ = 4000mm, L ₁ = 500mm, then the actual combined pressures on the three components are F ₁ = 8000kg, F ₂ = 7440kg, F ₃ = 6800kg, and the steel beam 4 will be the counterweight The total weight of magnified 8 times is applied on the member 5.

Then read the indications of the three dial gauges 16 to record, and then measure the deflection values on the 40th day, 205th day, 508th day, 885th day, and 1200th day, and each measurement is measured in a determined direction. , to ensure that the position of the measuring point remains unchanged. The three loading measurement processes are completely consistent.

During the above test process, the dial indicator 16 is not affected by slight disturbance after being fixed with the component 5, and it shows the advantages of good stability and integrity in the long-term measurement. The test result of loading and measuring device of the present utility model is as shown in table 1:

Table 1 Test results of loading and measuring devices

Remarks: (1) x% in the name of the test piece means the replacement rate of recycled coarse aggregate, for example, 50% means the test piece with a 50% replacement rate of recycled concrete; (2) Perimeter 1, Percentage 2, Percentage 3 Represent three dial gauges that the utility model adopts respectively; (3) Yd represents the dial gauge real-time data that reads when the test starts the Y day, such as 7d represents the dial gauge data recorded when the test starts the 7th day; (4) The reading unit of dial indicator 1, dial indicator 2 and dial indicator 3 is mm.

Claims (8)

1. A recycled concrete long-term deformation test loading and measuring device is characterized in that, comprising a special-shaped cap (6), above the special-shaped cap (6) is provided with two horizontal The positioning column (8) that slides in the direction, a component (5) is jointly supported above the two positioning columns (8), and a loading device is arranged above the component (5); A plurality of position-adjustable dial gauges (16) are arranged between the two positioning columns (8). 2. the recycled concrete long-term deformation test loading and measuring device as claimed in claim 1, is characterized in that, on the described special-shaped cap (6), a chute (10) is provided along its width direction, and the positioning column (8 ) can slide along the chute (10). 3. recycled concrete long-term deformation test loading and measuring device as claimed in claim 1, is characterized in that, described loading device comprises the steel beam (4) that is arranged horizontally and vertical with described member (5), and described steel beam (4) One end is connected to the special-shaped cap (6) through a vertical steel arm (9), and the steel beam (4) is movably connected to the steel arm (9); the other end of the steel beam (4) is installed below the Load the platform (3). 4. the recycled concrete long-term deformation test loading and measuring device as claimed in claim 3, is characterized in that, a distribution beam (11) is arranged between the steel beam (4) and the member (5); the distribution beam (11) and the member (5) are provided with a circular shaft support (12) and a triangular support (17), and the circular shaft support (12) and the triangular support (17) are arranged in the middle of the distribution beam (11) The position is symmetrically set. 5. the recycled concrete long-term deformation test loading and measuring device as claimed in claim 2, is characterized in that, a plurality of bearings (14) are arranged between the two positioning columns (8), and the bearings (14 ) can slide along the chute (10), and the dial indicator (16) is installed on the support (14). 6. The loading and measuring device for long-term deformation test of recycled concrete according to claim 4, characterized in that, a triangular support (13) is arranged between the positioning column (8) and the component (5). 7. The loading and measuring device for long-term deformation test of recycled concrete according to claim 3, 4 or 6, characterized in that the steel beam (4) and the steel arm (9) are connected by pins. 8. as the arbitrary described recycled concrete long-term deformation test loading and measuring device of claim 1 to 6, it is characterized in that, described special-shaped cap (6) is a symmetrical polygon.