System and method for controlling concrete production

• US 5,948,970 A
• Filed: 01/06/1998
• Issued: 09/07/1999
• Est. Priority Date: 07/06/1995
• Status: Expired due to Fees

• Current Assignee: Te'Eni, Moshe
• Original Assignee: Te'Eni, Moshe
• Inventors: Te'eni, Moshe
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): WIGGINS, JOHN DAVID
• Application Number:
  US08/981,807
• Time in Patent Office: 609 Days
• Field of Search: 73/54.03, 73/53.04, 73/54.39, 73/54.23, 73/54.37
• US Class Current: 73/54.03
• CPC Class Codes: B28B 17/02 Conditioning the material prior to shaping for mixtures containing clay or cement B28C
• CPC Class Codes: B28B 23/0031 with product identification means, e.g. labels on test products or integrated circuit tags inside products RFID
• CPC Class Codes: B28C 7/024 by measuring properties of the mixture, e.g. moisture, electrical resistivity, density
• CPC Class Codes: G01N 11/00 Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties
• CPC Class Codes: G01N 2011/0046 In situ measurement during mixing process
• CPC Class Codes: G01N 33/383 Concrete, cement

Abstract

A system is designed to measure concrete rheological properties which includes a concrete plant, a measuring unit and a mix changing unit. The measuring unit includes a surface in contact with a part of a mass of the concrete mix, a shearing unit for effecting shear deformation in the mass and at least one sensor which senses a measure of the force which is transferred to the surface by the concrete mass as a result of the shear deformation. The rheological profile is produced by: a) sensing at least one measure of the force which is transferred to the surface under at least two different stress states, b) determining i) the sensitivity of each of the at least one measure to a change in stress state and ii) the workability of the mix and c) creating the rheological profile from at least the sensitivity and workability.

Claims

1. A measuring system for measuring rheological properties of a concrete mix tested when contained, the system comprising:

a surface in contact with a part of a mass of said concrete mix;

a shearing unit for effecting shear deformation in said mass;

at least one sensor which senses a measure of the force which is transferred to said surface by said concrete mass as a result of said shear deformation under at least two measurement environments defining at least two different stress states; and

a confining envelope, wherein a space defined between said confining envelope and a rigid body of said shearing unit significantly changes shape with the movement of said rigid body during shear deformation, and wherein said at least one sensor senses a measure of the resistance of said concrete mass to shear during the operation of said shearing unit, wherein said resistance significantly changes during said operation as a result of said change in shape.

2. A method for generating a rheological profile of a given concrete mix, the method comprising the steps of;

effecting shear deformation in a mass of said concrete mix;

sensing at least two measures relating to the resistance of said concrete mass to said shear deformation;

generating, from said at least two measures, at least one variable relating to the workability of said concrete mix;

generating at least one additional variable from the ratio of two of said at least two measures; and

creating said rheological profile from said variables,

wherein said concrete mass changes shape during said step of effecting shear deformation, and wherein said step of sensing senses at least two different measures of the resistance of said concrete mass to shear during said shear deformation.

3. A method for the control of production and the design of concrete mixes to have desired rheological properties, the method comprising the steps of:

preparing a concrete mix in a concrete plant in accordance with a mix design indicating the proportions of solid components and water content of the concrete;

testing said prepared concrete mix with a concrete tester;

generating a rheological profile of said concrete mix from output of said step of testing;

comparing said generated rheological profile with a desired rheological profile defining desired properties of the concrete to be produced by said plant; and

adjusting said proportions of said solid components of said mix design in order to produce concrete having a rheological profile which is compatible with said desired rheological profile,

wherein said desired rheological profile comprise a measure of workability and at least one of the following factors and their related functions;

stress state sensitivity, stress distribution, shear rate sensitivity, vibration decay, vibratability, pumpability and deformability.

4. A system which designs and produces concrete to have desired rheological properties, the system comprising:

a plant for preparing a concrete mix in accordance with a mix design indicating the proportions of the solid components and water of the concrete;

a concrete profile measuring unit for measuring a rheological profile of the concrete produced by said plant; and

a mix changing unit for receiving said measured rheological profile and a desired rheological profile defining desired properties of the concrete produced by said plant and for indicating to said plant to adjust said solid components of said concrete mix, as many times as necessary, in order to produce concrete which has a rheological profile which is compatible with said rheological profile, said mix changing unit comprising a search unit for receiving a quality of change criterion and for determining the mix design change which will provide concrete having said rheological profile which is compatible with said desired rheological profile and which fits within said quality of change criterion, wherein said criterion is a function of the cost of the mix.