CN102564904A - Concrete viscometer - Google Patents

Abstract

A concrete viscometer relates to a viscometer, in particular to a concrete viscometer. The invention aims to solve the problem that the existing concrete viscometer cannot accurately measure the rheological parameters of the concrete. In the present invention, each slide rail is placed on the table of the test bench through two slide rail brackets, the long groove is placed on the table of the test bench, the frame is set on the roller, and a slide rail groove is respectively provided at both ends of the roller , the pulley is installed between the two slide rails, one end of the string is connected to the middle of one long side of the frame, the other end of the string is connected to the weight through the surface of the pulley, and the weight can pull the roller along the two sides by gravity. The slide rail moves on the horizontal plane, and there are two weight travel switches from top to bottom on the vertical surface at one end of the test bench. When the weight moves up and down along the vertical plane and passes the weight travel switch, the weight can touch Weight travel switches, each weight travel switch is connected with a timer. The invention is used for measuring the viscosity of concrete.

Description

A Concrete Viscometer

technical field

The invention relates to a viscometer, in particular to a concrete viscometer.

Background technique

The measurement method of rheological parameters of fresh concrete, according to the theory proposed by Bingham, at least two parameters of yield stress and plastic viscosity of fresh concrete should be measured. In order to measure these two parameters, foreign scholars have done Quite a few improvements. The famous scholar G.H.Tattersall and his students improved the structure of the rheometer and designed different forms of stirring paddles. Both Japanese and European peer scholars have done work on improving the rheometer. But so far, the data and relevant curves of the experimental reports of the rheological parameters of concrete by scholars from various countries are far from the relevant curves, and the conclusions of the experimental reports are very inconsistent. The main problems in existing concrete rheological parameter measurement are: 1. The stirring paddle cannot make the concrete form a stable and homogeneous laminar flow state; 2. It is inaccurate to measure the rotational moment of the drive shaft as the shear moment for calculating the viscosity.

Contents of the invention

In order to solve the problem that the existing concrete viscometer cannot accurately measure the rheological parameters of concrete, the invention further proposes a concrete viscometer.

The technical scheme adopted by the present invention to solve the above-mentioned problems is: the present invention includes a test bench, a long groove, a roller, a pulley, a weight, a frame, a string, two slide rails, two weight travel switches and four slide rails Each slide rail is placed on the table of the test bench through two slide rail brackets, and the two slide rails are arranged side by side on the table of the test bench, and the long groove is placed on the table of the test bench, and the long slot is set on the table of the test bench. Between the two slide rails, the frame is a rectangular frame composed of two short sides and two long sides. The frame is set on the rollers, and the two ends of the rollers are respectively connected to the inner middle of one short side of the frame. The two ends of the roller are respectively provided with a slide rail groove, and the slide rail grooves at both ends of the roller are respectively connected with a slide rail, and the wheels of the roller can penetrate into the concrete in the long groove, and the pulleys are installed in the two Between the two slide rails and located on the edge of one end of the workbench, one end of the string is connected to the middle of one long side of the frame, and the other end of the string is connected to the weight through the surface of the pulley, and the weight can pull the roller by gravity Move along the two slide rails on the horizontal plane. There are two weight travel switches from top to bottom on the vertical surface at one end of the test bench. When the weight moves up and down along the vertical plane and passes the weight travel switch, the weight can be When the weight travel switch is touched, each weight travel switch is connected with a timer.

The beneficial effects of the present invention are: the torque of the driving roller of the present invention is constant, the gravity on the weight is stable and reliable as the driving force, and has high precision; changing the weight of the weight can change the size of the driving force, that is, the roller can be changed The rotation speed of the wheel is easy to adjust; the three wheel pieces are immersed in the concrete, and it is easy to eliminate the influence of the unevenness inside the concrete on the test results; the invention has a simple structure, no power drive, easy manufacture, and low cost; With higher precision, the plastic viscosity of concrete can be accurately measured.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of the present invention, Fig. 2 is a left sectional view of Fig. 1, and Fig. 3 is a sectional view of the frame.

Detailed ways

Specific embodiment 1: This embodiment is described in conjunction with Fig. 1, Fig. 2 and Fig. 3. A concrete viscosity meter described in this embodiment includes a test bench 1, a long groove 2, a roller 3, a pulley 4, a weight 5, and a frame 6. Thin rope 10, two slide rails 7, two weight travel switches 8 and four slide rail brackets 9, each slide rail 7 is placed on the table top of the test bench 1 through two slide rail brackets 9, and the two The slide rails 7 are arranged side by side and parallel on the table top of the test bench 1, the long groove 2 is placed on the table top of the test bench 1, and the long slot 2 is arranged between the two slide rails 7, and the frame 6 is composed of two short sides 6 -1 and two long sides 6-2 form a rectangular frame, the frame 6 is set on the roller 3, and the two ends of the roller 3 are respectively connected to the inner middle part of a short side 6-1 of the frame 6, and the roller The two ends of 3 are respectively provided with a slide rail groove 3-1, and the slide rail grooves 3-1 at both ends of the roller 3 are respectively slidably connected with a slide rail 7, and the wheels 3-3 of the roller 3 can penetrate into the In the concrete in the long groove 2, the pulley 4 is installed between two slide rails 7, and is positioned at the edge of one end of the workbench 1, and one end of the string 10 is connected with the middle part of a long side 6-2 of the frame 6, and the string The other end of 10 is connected with the weight 5 through the surface of the pulley 4, and the weight 5 can rely on the gravity to pull the roller 3 to move along the two slide rails 7 on the horizontal plane. There are two weight travel switches 8, each weight travel switch 8 is connected with the timer, when the weight 5 moves up and down along the vertical plane and passes the weight travel switch 8, the weight 5 can touch the weight travel switch 8.

Specific embodiment two: this embodiment is described in conjunction with Fig. 1 and Fig. 2, the roller 3 of a kind of concrete viscometer described in this embodiment is made up of rotating shaft 3-2 and three wheel pieces 3-3, three wheel pieces 3 -3 are arranged side by side in parallel and equidistantly on the rotating shaft 3-2, and each wheel piece 3-3 is fixedly connected to the rotating shaft 3-2 as a whole. In this embodiment, the thickness of the wheel is 5 mm to 10 mm, and the depth of the wheel immersed in concrete is 1/3 to 1/2 of the concrete depth. Other components and connections are the same as those in the first embodiment.

Specific embodiment three: this embodiment is described in conjunction with Fig. 1, the height H of the table top of the test bench 1 of a kind of concrete viscometer described in this embodiment and the ground is 800mm, between each slide rail 7 and the table top of test bench 1 The distance L is 180mm. Other compositions and connections are the same as those in Embodiment 1 or 2.

working principle

Fill the long groove 2 with concrete samples to make the surface of the concrete sample smooth, place the two ends of the roller 3 on the two slide rails 7 respectively, and make the three wheels 3-3 of the roller 3 enter the concrete In the sample, the weight 5 relies on gravity to pull the roller 3 to move horizontally along the slide rail 7, and the concrete produces resistance to the rolling of the wheel 3-3. When the weight 5 passes the weight up travel switch 8 from top to bottom, the timer Start timing, and when the weight 5 passes through the lower weight travel switch, the timer stops timing. If the weight 5 passes the distance between the two weight travel switches as S, and the time it takes for the weight to pass the distance S is T through the timer, then the weight’s descending rate V=S/T, and the weight’s descending rate V It is related to the moving speed of the roller 3 on the slide rail 7 . Since the wheel 3-3 penetrates into the concrete, the rate of descent V of the weight is related to the viscosity of the concrete. When the weight of the weight is constant, the greater the viscosity of the concrete, the slower the rate of decline of the weight V. By changing the weight of the weight, different weight descending rates are obtained. A one-variable linear fitting equation of the weight of the weight and its descending rate is established. The slope of the equation can be used to characterize the plastic viscosity of concrete, and the intercept can be used to characterize the yield stress of concrete.

The calibration method of instrument: select the standard fluid such as castor oil of a known viscosity coefficient η ₀ for use, utilize measuring device of the present invention, according to above-mentioned operation process, set up the relationship curve between weight weight and weight descending rate, with weight The descending rate is the abscissa, and the weight of the weight is plotted as the ordinate. The proportional coefficient between the slope of the one-dimensional linear equation obtained after linear fitting and the viscosity value of the standard fluid is the instrument constant κ. The plastic viscosity of fresh concrete can be obtained by dividing the slope of the linear relationship curve between the weight of the weight in the fresh concrete and the rate of decline of the weight by the instrument constant κ.

Claims (3)

1. A concrete viscometer is characterized in that: said a kind of concrete viscometer comprises test bench (1), long groove (2), roller (3), pulley (4), weight (5), frame (6), string (10), two slide rails (7), two weight travel switches (8) and four slide rail brackets (9), each slide rail (7) passes through two slide rail brackets (9) Placed on the table of the test bench (1), and two slide rails (7) are arranged side by side and parallel on the table of the test bench (1), and the long slot (2) is placed on the table of the test bench (1) , and the long slot (2) is set between two slide rails (7), the frame (6) is a rectangular frame composed of two short sides (6-1) and two long sides (6-2), The frame (6) is set on the roller (3), and the two ends of the roller (3) are respectively connected to the inner middle part of a short side (6-1) of the frame (6), and the two ends of the roller (3) Each is provided with a slide rail groove (3-1), and the slide rail grooves (3-1) at the two ends of the rollers (3) are slidably connected with a slide rail (7) respectively, and the wheels of the rollers (3) The sheet (3-3) can penetrate into the concrete in the long groove (2), the pulley (4) is installed between the two slide rails (7), and is located at the edge of one end of the workbench (1), and the string (10) One end of the rope (6) is connected to the middle of one long side (6-2) of the frame (6), and the other end of the string (10) is connected to the weight (5) through the surface of the pulley (4), and the weight (5) can rely on Gravity pulls the rollers (3) to move on the horizontal plane along the two slide rails (7), and two weight travel switches (8) are arranged from top to bottom on the vertical plane at one end of the test bench (1). The weight travel switch (8) is connected with the timer, and when the weight (5) moved up and down along the vertical plane and passed the weight travel switch (8), the weight (5) could touch the weight travel switch (8). 2. A kind of concrete viscometer according to claim 1, is characterized in that: described roller (3) is made up of rotating shaft (3-2) and three wheel pieces (3-3), and three wheel pieces (3-3) -3) The rotating shafts (3-2) are arranged side by side in parallel and equally spaced, and each wheel piece (3-3) is fixedly connected with the rotating shaft (3-2) into one body. 3. according to claim 1 and 2 described a kind of concrete viscometer, it is characterized in that: the height (H) of the table top of described test bench (1) and ground is 800mm, and every slide rail (7) and test bench ( 1) The distance (L) between the table tops is 180mm.

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