# US 2014/0360406 A1 · Asphalt foam collapse test methods and related apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0360406 A1 - Document ID: US20140360406A1 - Status: Published application - Kind: A1 - Application number: 14/299,483 - Filed: 2014-06-09 - Published: 2014-12-11 - Earliest claimed: 2013-06-10 - Assignees: Board of Trustees of Michigan State University - Applicants: Board of Trustees of Michigan State University - Inventors: Muhammed Emin Kutay; Hande Isik Ozturk - Web page: https://patentgrep.com/patent/US20140360406A1 ## CPC - C08L 95/00: Compositions of bituminous materials, e.g. asphalt, tar, pitch - G01N 33/42: Road-making materials (G01N33/38 takes precedence) - C08L 2555/10: Design or test methods for bitumen or asphalt mixtures, e.g. series of measures, procedures or tests to obtain a bitumen or asphalt mixture having preset defined properties, general or international test methods, procedures or standards - Y02A 30/30: in transportation, e.g. on roads, waterways or railways - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - Y02A: TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE ## Abstract The disclosure relates to asphalt foam collapse test methods and related apparatus for the measurement and determination of foamed asphalt binder quality, in particular warm-mix asphalt. Various asphalt binder/foam quality indicators can be measured according to the disclosure, such as bubble size distribution, bubble surface area, foam expansion ratio, foam half-life, foam index, as well as normalized parameters related to the same. The disclosed methods and apparatus permit the repeatable characterization and formation of foamed asphalt compositions, enabling the skilled artisan to form foamed asphalt/aggregate compositions of known, repeatable quality. This enhances the ability to form WMA foamed asphalt concrete with controlled and favorable properties selected for the particular environmental conditions (e.g., climate-, weather-, and/or traffic-related) where the concrete is to be used. ## Claims ### Claim 1 A method for determining foamed asphalt quality, the method comprising: (a) providing a foamed asphalt comprising an asphalt medium and a plurality of bubbles dispersed throughout the asphalt medium; (b) allowing the foamed asphalt to decay and measuring the amount of the foamed asphalt as a function of time during decay to provide an amount time series for the decaying foamed asphalt; (c) determining from the amount time series at least one foam quality parameter selected from the group consisting of bubble size distribution parameters, bubble surface area parameters, and combinations thereof; and (d) comparing the foam quality parameter with at least one corresponding foam quality set point. ### Claim 2 (depends on 1) The method of claim 1, wherein at least one foam quality parameter is a bubble size distribution parameter. ### Claim 3 (depends on 2) The method of claim 2, wherein: (i) the bubble size distribution parameter is an average bubble size of the distribution of bubbles prior to measuring the amount of the foamed asphalt as a function of time, and (ii) the corresponding foam quality set point is selected from the group consisting of a minimum, a maximum, or a range for the average bubble size. ### Claim 4 (depends on 3) The method of claim 3, wherein the average bubble size is normalized relative to a selected characteristic aggregate size. ### Claim 5 (depends on 1) The method of claim 1, wherein at least one foam quality parameter is a bubble surface area parameter. ### Claim 6 (depends on 5) The method of claim 5, wherein the bubble surface area parameter is a normalized total surface area of all bubbles present in the foamed asphalt prior to measuring the amount of the foamed asphalt as a function of time. ### Claim 7 A method for determining foamed asphalt quality, the method comprising: (a) providing a foamed asphalt comprising an asphalt medium and a plurality of bubbles dispersed throughout the asphalt medium; (b) allowing the foamed asphalt to decay and measuring the height of the foamed asphalt along a measurement axis and as a function of time during decay to provide a height time series for the decaying foamed asphalt, wherein the measurement axis is substantially parallel to a decay direction defined by the decaying foamed asphalt; (c) determining from the height time series at least one foam quality parameter; and (d) comparing the foam quality parameter with at least one corresponding foam quality set point. ### Claim 8 (depends on 7) The method of claim 7, wherein the foam quality parameter is selected from the group consisting of bubble size distribution parameters, bubble surface area parameters, integral decay properties, characteristic decay times, and combinations thereof. ### Claim 9 (depends on 7) The method of claim 7, further comprising: adding a buoyant marker to an external surface of the foamed asphalt, wherein measuring the height of the foamed asphalt comprises measuring the height of the buoyant marker. ### Claim 10 (depends on 9) The method of claim 9, wherein the buoyant marker is sufficiently sized to reduce erratic movement of the buoyant marker resulting from bubbles escaping from the foamed binder during decay. ### Claim 11 (depends on 1) A method for determining foam generation conditions, the method comprising: (a) providing a first foamed asphalt formed at a first set of foam generation conditions; (b) determining foamed asphalt quality according to the method of claim 1 for the first foamed asphalt; (c) providing a second foamed asphalt formed at a second set of foam generation conditions different from the first set of foam generation conditions; and (d) determining foamed asphalt quality according to the method of claim 1 for the second foamed asphalt. ### Claim 12 (depends on 11) The method of claim 11, comprising performing parts (a)-(d) as an automated process in a feedback control loop. ### Claim 13 (depends on 1) A method for forming an asphalt concrete composition, the method comprising: (a) providing a foamed asphalt comprising an asphalt medium and a plurality of bubbles dispersed throughout the asphalt medium; (b) determining foamed asphalt quality according to the method of claim 1 for the foamed asphalt; and (c) mixing aggregate with the foamed asphalt to provide the asphalt concrete composition. ### Claim 14 (depends on 13) The method of claim 13, wherein the aggregate is selected from the group consisting of stone, gravel, sand, and combinations thereof. ### Claim 15 (depends on 13) The method of claim 13, wherein: (i) the asphalt medium is present in an amount ranging from 2 wt. % to 10 wt. % relative to the asphalt concrete composition; and (ii) the aggregate is present in an amount ranging from 90 wt. % to 98 wt. % relative to the asphalt concrete composition. ### Claim 16 (depends on 13) A method for forming multiple asphalt concrete compositions, the method comprising: (a) performing the method of claim 13 to form at least two asphalt concrete compositions, wherein: (i) the aggregate has a different characteristic size in each composition; and (ii) the foamed asphalt has a selected different foam quality corresponding to the aggregate characteristic size in each composition. ### Claim 17 An apparatus for measuring foamed asphalt quality, the apparatus comprising: (a) a vessel for containing a foamed asphalt sample, the vessel defining a foam decay direction; and (b) a means for measuring the height of a foamed asphalt sample in the vessel as a height time series in real time, wherein: (i) the height measuring means defines a measurement axis, and (ii) the height measuring means is positioned remotely from the vessel and such that the measurement axis is substantially parallel to the foam decay direction. ### Claim 18 (depends on 17) The apparatus of claim 17, wherein the height measuring means comprises a first buoyant marker positionable within the vessel. ### Claim 19 (depends on 18) The apparatus of claim 18, wherein the height measuring means further comprises a second marker spatially coupled to the first buoyant marker. ### Claim 20 (depends on 19) The apparatus of claim 19, wherein the height measuring means further comprises a means for optically measuring spatial displacement of the second marker. ### Claim 21 (depends on 18) The apparatus of claim 18, wherein the first buoyant marker is coated with an asphalt binder. ### Claim 22 (depends on 18) The apparatus of claim 18, wherein the height measuring means further comprises a means for measuring at least one of translational or rotational movement corresponding to movement of the first buoyant marker.