CN102539657A - Apparatus for measuring the actual loss of concrete slump - Google Patents

Abstract

The present invention discloses a device for measuring the actual slump loss of concrete, which can simulate the actual transportation state of concrete, that is, can reduce the construction cost and ensure the working performance of concrete. The device comprises a fixed frame (1), the fixed frame (1) is fixedly connected to the axial sides of a cylinder (3) through a bearing (2), and the cylinder (3) is provided with a feed port (4) and a discharge port (5); a rotating shaft (6) passing through the bearing (2), one end of the rotating shaft (6) located outside the cylinder (3) is connected to a power device, and a stirring blade (7) is fixed on the rotating shaft (6) located inside the cylinder (3).

Description

Apparatus for measuring the actual loss of concrete slump

technical field

The invention relates to the technical field of performance evaluation of concrete construction, in particular to a device for measuring the actual loss of concrete slump which can simulate the actual transportation state of concrete, which can reduce the construction cost and ensure the working performance of concrete.

Background technique

At present, in the field of civil engineering, commercial concrete is constructed by pumping, so it is required that the concrete must have a certain fluidity, and its fluidity is usually measured by slump. Since the slump of concrete will decrease after being transported (called slump loss), the initial slump of concrete transported from the concrete mixing station must be the sum of the construction standard value and the slump loss value. In order to ensure the working performance of pouring site concrete. The existing method for measuring the slump loss of concrete is: take part of the freshly mixed concrete, measure its slump with a slump cylinder, and the obtained value is the initial slump; the remaining part is placed in a closed container , stand still for a certain period of time (the transportation time for the concrete transport vehicle to carry out pumping operation from the mixing station to the construction site), and then use the slump cylinder to measure the slump, and the difference between the obtained value and the initial slump is the corresponding time Slump loss. However, in actual engineering, the commercial concrete is always in the uniform rotation of the tank during transportation, and the uniform rotation can slow down the concrete setting. Compared with the concrete placed in the container in the existing measurement method, the slump loss is small. That is, there is an error between the slump loss measured by the existing method and the actual loss. Due to the existence of errors, the initial slump of the concrete is too large, which not only wastes the admixture of the concrete, increases the cost of the concrete, but also causes early cracks in the concrete components, reducing the durability of the components.

Contents of the invention

The present invention aims to solve the above-mentioned technical problems existing in the prior art, and provides a method for measuring the actual loss of concrete slump which can simulate the actual transportation state of concrete, which can reduce the construction cost and ensure the working performance of concrete. device.

The technical solution of the present invention is: a device for measuring the actual loss of concrete slump, which is provided with a fixed frame, and the fixed frame is fixedly connected with the axial sides of the cylinder through bearings, and the cylinder has advanced The feed port and the discharge port are provided with a rotating shaft passing through the bearing, one end of the rotating shaft outside the cylinder is connected with the power equipment, and stirring blades are fixed on the rotating shaft inside the cylinder.

The power equipment includes a motor arranged at the bottom of the fixed frame, a reduction box, a driving wheel, a transmission belt and a driven wheel fixed at one end of the rotating shaft.

The inlet is arranged on the radial side of the cylinder, and the outlet is arranged on the axial end surface of the cylinder.

The agitating blades are at least three rows, uniformly distributed in the left, middle and right in the axial direction of the cylinder body and inclined to the rotating shaft.

When measuring the concrete slump loss, the present invention can simulate the actual transportation state of the concrete, can accurately measure the actual concrete slump loss, and solves the problem that the existing measurement method does not conform to the actual engineering application and causes errors, and can Relatively reducing the initial slump of concrete and avoiding defects caused by excessive initial slump of concrete can not only reduce the project cost, but also ensure the working performance of concrete.

Description of drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

Detailed ways

The specific implementation manner of the present invention will be described below with reference to the accompanying drawings. As shown in Figure 1: there is a fixed frame 1 made of high-quality section steel, and the fixed frame 1 is equipped with two bearings 2, and the fixed frame 1 is fixedly connected with the axial sides of the cylinder body 3 through the bearing seats of the bearings 2. The cylinder body 3 is welded by alloy materials. The volume of the cylinder body 3 is 11.4 liters, the cylinder wall thickness is 4 mm, the cylinder inner diameter is 220 mm, and the cylinder length is 300 mm. There is an inlet 4 and an outlet 5 on the cylinder 3. The feed port 4 is preferably arranged on the radial side wall of the cylinder body 3 , and the discharge port 5 is preferably arranged on the axial end wall of the cylinder body 3 . There is a rotating shaft 6 passing through the bearing 2, one end of the rotating shaft 6 outside the cylinder body 3 is connected with the power equipment, and a stirring blade 7 is fixed on the rotating shaft 6 inside the cylinder body 3. The power equipment includes a motor 8 arranged at the bottom of the fixed frame 1, a reduction box 9, a driving wheel 10, a transmission belt 11 and a driven wheel 12 fixed on one end of the rotating shaft 6, and a control box 13 is connected with the motor 8. There are at least three rows of agitating blades 7, which are evenly distributed in the left, middle and right directions in the inner axis of the cylinder body 3 and are inclined to the rotating shaft 6. The blade 7 can be consistent with the shape of a marine propeller.

work process:

a. Wet the cylinder body 3 and the slump cylinder with a damp cloth;

b. Through the control box 13, start the power supply of the motor 8, and the rotating shaft 6 drives the blade 7 to start rotating, and the rotating speed is equivalent to the rotating speed of the concrete transport vehicle drum, such as 3.6 rpm;

c. Take out part of the concrete to be transported at the mixing station, measure the initial slump, and at the same time put the remaining concrete into the cylinder 3 from the feed port 4, and start reading the meter;

d. When the time reaches the time when the concrete transport vehicle arrives at the construction site, quickly reverse the rotating shaft 6, the concrete is discharged from the discharge port 5, and the concrete is poured into the slump cylinder at a uniform speed for secondary slump measurement and record;

e. Calculate the slump value twice, which is the actual slump loss during transportation.

Claims (4)

1. A device for measuring the actual loss of concrete slump, characterized in that: a fixed frame (1) is provided, and the fixed frame (1) is fixed on both axial sides of the cylinder (3) through the bearing (2) Connected, the cylinder (3) has a feed inlet (4) and a discharge outlet (5); there is a rotating shaft (6) passing through the bearing (2), and the rotating shaft (6) outside the cylinder (3) 6) One end is connected to the power equipment, and the stirring blade (7) is fixed on the rotating shaft (6) inside the cylinder (3). 2. The device for measuring the actual loss of concrete slump according to claim 1, characterized in that: the power equipment includes a motor (8) and a reduction box (9) arranged at the bottom of the fixed frame (1) , driving wheel (10), transmission belt (11) and the driven wheel (12) that is fixed on rotating shaft (6) one end. 3. The device for measuring the actual loss of concrete slump according to claim 1 or 2, characterized in that: the feed inlet (4) is arranged on the radial side of the cylinder (3), the The discharge port (5) is arranged on the axial end surface of the cylinder (3). 4. The device for measuring the actual loss of concrete slump according to claim 3, characterized in that: the agitating blades (7) are at least three rows, in the middle left of the inner axis of the cylinder (3) Right evenly distributed and inclined with the axis of rotation (6).

Images