EP1407262A1 - Monitoring fill soil via compactor rolling resistance - Google Patents
Monitoring fill soil via compactor rolling resistanceInfo
- Publication number
- EP1407262A1 EP1407262A1 EP01935521A EP01935521A EP1407262A1 EP 1407262 A1 EP1407262 A1 EP 1407262A1 EP 01935521 A EP01935521 A EP 01935521A EP 01935521 A EP01935521 A EP 01935521A EP 1407262 A1 EP1407262 A1 EP 1407262A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- energy
- density
- soil
- compaction
- engineering
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/24—Earth materials
Definitions
- This invention encompasses new methods for and in earthen fill engineering and construction and includes application to treated and amended soils for subgrades and base courses. More specifically this invention involves new and different methods to determine, use, and model in the laboratory, actual field compaction energy generated by all combinations of compactors, soil types, lift thickness', moisture contents, and soil amendments; and the application of these methods in engineering design, specification, and construction control methods, based on methods to derive and correlate rolling resistance energy, cumulative compaction energy, soil moisture, density, and geotechnical engineering properties.
- the specification and control of density and moisture of earthen fill is typically based on the results of the Standard Proctor compaction test (American Society for Testing Materials [ASTM] D698) or the Modified Proctor compaction test (ASTM D1557), or other similar test standards derived from the Proctor tests and established by other institutes and governments (i.e. AASHTO, etc.). All standard tests used in current practice utilize fixed soil compaction energies.
- the compaction energy used in the standard proctor compaction test is 600 kilonewton-meter per cubic meter Kn-m/m 3 or 12,400 foot pounds per cubic foot (ft-lbs/cf).
- the other standard tests based on the Standard Proctor Test use the same or comparable fixed energy levels.
- the invention is based on rimpull compactor energy instead of drawbar pull energy in current practice.
- the invention is based on cumulative compaction energy levels that vary with site conditions and/or engineering needs, instead of fixed cumulative compaction energy levels that do not vary with site conditions or engineering needs.
- the invention provides for a different method for determining compaction energy and associated moisture-density/engineering property relations for any given combination of soil type, compactor, moisture state, lift thickness, and soil amendment, by tracking energy distribution, determining field-specific rolling resistance and correlating such determinations to cumulative compactive energy loss and engineering properties of the compacted lift, under practical and controlled construction conditions.
- the invention establishes these different methods by factoring lift thickness, soil moisture content, and soil amendments with the soil/compactor combinations, and the variations thereof, as opposed to any methods based solely on soil/compactor combinations, and by including other methods that differ from prior art.
- the different methods include determining the unit cumulative compactive energy per unit volume at the asymptotic energy-density approach for each rolling resistance field trial by using the cumulative average rolling resistance according to each parabolic data curve, in contrast to the prior published method (Tritico/Langston, 1994,1995) of using the cumulative linear average rolling resistance.
- the different methods further include determining the "design energy level" for (/-Ulaboratory modeling based on establishing a specific percentage density sector of the derived moisture-density curves at or within the asymptotic energy- density approach, which is projected onto a corresponding roller compaction energy curve, in contrast to the prior art of selecting a random energy value based on visual observation of energy-density-moisture graphs.
- the specific density sector method involves a specific percentage value selected within the range of 85 to 100 % of the maximum density values on the derived moisture-density curves at or within the asymptotic energy-density approach projected onto corresponding roller compaction energy curves.
- the selected percentage density sector is projected onto a corresponding roller energy curve selected from the group of curves at or within the asymptotic energy-density approach.
- the new method further includes determination of the asymptotic energy-density approach based on combination-specific results of full-scale field trials including all combinations of lift thickness, soil type, soil amendments, moisture content, and compactor type, as opposed to the prior art of a generalized asymptotic energy-density approach of an 8-10 or 8-12 pass range based solely on the soil/compactor combination, and conventional expectations of roller "walk-out".
- the different, specific methods operate together to define the new method.
- the method may be applied to specific compactors such as determining the actual, cumulative field compaction energy for a Cat 815B compactor for a given soil, such as type CH, with a certain moisture state, lift thickness, and soil amendment type, and correlation, use and control of resultant engineering properties for new engineering and construction methods.
- the invention provides a data matrix of field combination- specific compaction energy correlation factors for various combinations of soil type, soil amendment, moisture content, lift thickness, and compaction rollers, developed with the new methods, and uses of the established data matrix to determine field- specific compaction energy correlations for untested field combinations.
- the data matrix may be used in conjunction with other improvements to extrapolate from known values to untested field combinations based on extrapolation of data for tested soils or equipment.
- the invention may also be viewed as a data matrix comprising a set of actual field compaction energy correlation factors for various soil densities, moisture contents, and other engineering properties for a plurality of soil types, a plurality of soil compactors, a plurality of lift thickness', a plurality of soil amendments, or a plurality of all the above.
- the invention includes new engineering and construction methods which utilize a data matrix to provide an alternate method for computing design compaction energy and extrapolations and/or interpolation of correlating engineering data established in the data matrix, for laboratory modeling, engineering design and specifications, and or construction testing and controls.
- the new methods include generation of the data matrix based on the new methods outlined above and novel methods for determining specific asymptotic energy-density approach ranges from data sets of rolling resistance trials based on field-specific combinations of soil types, compactors, moisture contents, lift thickness', and soil amendments.
- the new method includes utilization of asymptotic energy-density approach ranges, constituting ranges of 2 to 5 passes, from within the group of 6 to 20 passes, as opposed to a sole soil/compactor combination basis, or generalization of an 8-12 or 8-10 pass range.
- the invention may also be viewed as a data matrix, based on and utilized as and a part of, the new and different methods outlined herein, comprising a set of field combination-specific rolling resistance energy correlations for a plurality of soil types, compactors, lift thickness', moisture contents, and soil amendments, and relating associated maximum soil densities, optimum moisture contents, and other engineering properties, and the data is displayed or used for new engineering and construction control methods, and in a manner that permits determining values for additional field combinations by extrapolation, or actual field trial.
- Figure 1 is a plot of the change in rolling resistance and density with roller passes based on rimpull energy of a Caterpillar Model 815B compactor combined with a "CH” soil, for a typical field trial developed by the Inventors. DETAILED DESCRIPTION OF THE INVENTION
- AASHTO means American Association of State Highway and Transportation
- Compaction Energy means the energy component that is transferred by a compaction roller into the ground over which it is travelling, and represents the energy that causes soil densification.
- “Asymptotic Energy-Density Approach” means a segment of a data set of rolling resistance-density curves, as a function of specific combinations of soil type, lift thickness, moisture content, compactor type, and soil amendment, wherein the incremental change in rolling resistance and corresponding soil densification begins to be insignificant with successive roller passes.
- “Best fit curve” means the curve plotted through a set of data points that best fits the data trends and variations by methods of bilinear or curvilinear approximation or averaging, and educated visual extrapolations.
- “Cumulative average rolling resistance” means the rolling resistance measured by the method of example 2 below.
- Design energy level means a cumulative compaction energy level considered to be representative of actual field energies produced by compactor-soil-moisture-lift thickness-soil amendment combinations, at a select point within the novel asymptotic energy-density approach, computed by the method of example 3 below.
- the Design Energy Level is used for laboratory compaction testing and other engineering applications. In laboratory compaction testing, the design energy level is utilized in procedures of a Standard or Modified Proctor test (and standard variations thereof) by varying the fixed energy specified in the standard test procedures to utilize the design energy.
- Rolling resistance is defined as the fraction of rimpull energy needed to overcome ener y loss into the earthen lift being compacted, as determined using compactor rimpull curves provided by the equipment manufacturer.
- Figure 1 represents a basic, prior art (Tritico/Langston) illustration of rolling resistance vs. soil densification with roller passes, produced by a given soil-compactor combination.
- rolling resistance reduces, as the soil densifies with each roller pass.
- Both rolling resistance and soil density reach asymptotic states at the same rate. This effect is the result of decreasing soil deformation with increasing compaction.
- compaction energy transferred from a wheel- ground system is a function of rolling resistance and that rolling resistance is a function of the compactor's rimpull energy as opposed to drawbar pull energy.
- Current practice is based on drawbar pull energy as authored by R.R. Proctor in the development of standard methods.
- the invention encompasses new and different methods for determining actual, cumulative field compaction energy based on rolling resistance measurements as a function of rimpull energy, and by relating rolling resistance to compactor type, dry density, moisture content, lift thickness, soil type, and soil amendments, with each roller pass; as opposed to measuring rolling resistance or estimating compaction energy based on just a soil/compactor combination with each roller pass.
- the invention includes the correlation of engineering properties of compacted soils to the actual cumulative compaction energy levels, as opposed to fixed energy levels and standard practices.
- the invention also includes methods for and of the development and utilization of data matrices of these correlations in and for different engineering design, construction, and construction testing and control methods, as opposed to standard practices.
- Example 1 In a field test program the rolling resistance of a wheel/ground system suitable for earthen fill construction is measured relative to soil type, compactor type, soil lift thickness, moisture content, dry density, soil amendments, and roller passes. A specific test pad design is built with a certain soil type at different loose lift thickness', moisture contents, and soil amendments. Various earthwork compactors are used for the test and the compactor's performance parameters and specifications are recorded.
- the field test program consists of a series of at least three test trials. For each lift thickness, initial moisture content, soil type, soil amendment, and compactor type, each trial involves the determination of rolling resistance, soil dry density, and soil moisture content with each roller pass, and other engineering properties at and within the asymptotic energy-density approach range.
- Each trial is conducted with a different initial moisture content in order to test a range that encompasses the true optimal moisture content for the energy being applied, and to test for specific moisture contents for correlation with certain engineering properties based on soil type and for purposes of engineering design requirements and the new engineering methods.
- Each trial is continued until changes in field measurements are clearly extended through the full asymptotic energy-density approach range and the full range is clearly defined.
- Rolling resistance is measured based on test pad configuration and rimpull performance using rimpull performance curves for the test compactors.
- the data from each trial are plotted in a manner similar to that shown in figure 1.
- the asymptotic energy-density range is determined from the plots for the range needed depending on the application of the novel engineering methods.
- Rolling resistance is based on measurement of rimpull energy performance in each test trial. Best fit curves of dry density vs. rolling resistance with each roller pass are developed in graphical and tabular form. Based on the combination-specific results in the plots, for each trial, novel asymptotic energy-density approaches are determined as a range composite of 2 to 5 passes, within a pass range of 6 to 20 passes; as opposed to generalization of an 8-10 or 8-12 pass range based solely on a soil/compactor combination.
- the methods include selecting a pass interval in the novel asymptotic energy-density approach, to determine cumulative average compaction energy levels in order to determine a "design compaction energy" (or a select unit cumulative compaction energy per unit volume) from combination-specific moisture-density, and moisture-energy curves, based on and for use in novel methods. Selection of the pass interval in the novel asymptotic range is based on the project-specific needs, criticality, and factor of safety intents in practical application of the methods.
- the prior art (published by the current inventors) for determination of the "design energy level” was based on selecting a random, generalized energy value based on visual observation and averaging of energy-density-moisture graphs, based solely on a soil- compactor combination, at a generalized asymptotic energy-density approach of 8-10 passes.
- the novel "design energy levels” are determined based on the multitude of field combinations and resultant asymptotic approach intervals and used for modeling in laboratory compaction testing, and correlation with engineering properties of corresponding compacted lifts.
- the invention includes a method for computation of cumulative average rolling resistance for each field trial from the best fit parabolic data curve formed by the trials. This is accomplished as follows: For each rolling resistance vs. dry density curve produced by plotting the measured results for several data points in each pass of each field trial, new compaction data is drawn directly from the best fit, parabolic curve formed by plotting the rolling resistance variance with roller passes. Along the line of the curve, rolling resistance values for each wheel pass are drawn directly from the curve, for cumulative averaging. The cumulative averages are made with values taken from the first wheel pass up to the select pass at or within the novel asymptotic energy-density approach.
- the invention includes a method to determine the novel "design energy level" based on selection of a specific percentage density sector of the derived moisture- density curves at or within the novel asymptotic energy-density approach, which is projected onto a corresponding roller compaction energy curve. This is accomplished as follows:
- a specific percentage density sector is selected or “notched” out of the select or corresponding density curve(s) in order to define a "design range” of moisture contents.
- the specific percentage value is selected within the range of 75 to 100% of the maximum density values on the derived moisture density curves, preferably 80 to 100% more preferably 85 to 100%, based on engineering needs with the new engineering methods. These needs include project-specific criticality and factor of safety requirements in practical application of the new methods.
- This "design range” per novel selection methods is then projected onto the corresponding roller compaction energy curve(s) on the same chart.
- the intercept sector formed by the design range projection onto the roller energy curves is then used to derive a "design energy level" by direct reading from the chart, and is used for laboratory simulation of field compaction energy and the other novel methods described herein.
- a data matrix that cross-matches some or all combinations of compactor and soil types or amended soils, for each and any combination of lift thickness and moisture content, including combination interpolations is developed and used in the methods of the invention.
- a data set within each cross-match within each matrix includes the following corresponding data values: "design energy levels" or actual cumulative field compaction energy levels covering the percentage range of selected density sectors, the asymptotic energy-density approach ranges, maximum dry density values, optimum moisture content values, energy correlation factors for laboratory testing, factor of safety values for engineering uses, and any and all engineering properties for the corresponding compacted lift product. Examples of other engineering properties are shear strength, modulus, consolidation, CBR, permeability, index properties, etc.
- novel design energy levels and correlation factors for all said field combinations and interpolations are tabulated in cross-matrices.
- the factors are used as multiplying factors for modeling field compaction energy whereby the factor is used to adjust standard laboratory compaction testing to model actual, combination-specific compaction energy of earthen fill materials.
- Also included in the matrix are the novel asymptotic energy- density approach ranges and all other said engineering properties which correspond to the compacted lift product.
- the novel matrix is also used as a part of the new methods to interpolate or extrapolate between cross-matrix values for untested field combinations.
- the novel data matrix of example 4 is also used as a part of the new method to model actual, cumulative field compaction energy (or "design energy levels") in the laboratory for production of field-representative moisture-density compaction curves, or to assess compaction energies for other engineering uses.
- the novel compaction energy values drawn from the novel matrix are based on the novel asymptotic energy- density approach ranges and percentage density sectors, for any combination of the novel field parameters (soil type, compactor type, lift thickness, moisture content, and soil amendment).
- the novel energy correlation values or multiplying factors are applied to the height or number of hammer drops in the Standard or Modified Proctor Test procedures, or other standard test procedures derived from the Proctor Test standards, to model the novel compaction energy in the procedure instead of the specific fixed energy levels produced by the standard test procedures.
- the modified laboratory compaction testing based on novel compaction energy values and associated methods to determine and use the energy values, field combination-specific moisture-density compaction curves are produced for practical application.
Abstract
Description
Claims
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/US2001/015638 WO2001088529A1 (en) | 2001-05-15 | 2001-05-15 | Monitoring fill soil via compactor rolling resistance |
Publications (2)
Publication Number | Publication Date |
---|---|
EP1407262A1 true EP1407262A1 (en) | 2004-04-14 |
EP1407262A4 EP1407262A4 (en) | 2006-08-23 |
Family
ID=21742572
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP01935521A Ceased EP1407262A4 (en) | 2001-05-15 | 2001-05-15 | Monitoring fill soil via compactor rolling resistance |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP1407262A4 (en) |
CN (1) | CN100414295C (en) |
AU (2) | AU2001261609B2 (en) |
CA (1) | CA2447157C (en) |
WO (1) | WO2001088529A1 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6182040B2 (en) * | 2013-10-03 | 2017-08-16 | 前田建設工業株式会社 | Management method of low water permeability of compacted soil |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3444727A (en) * | 1965-06-04 | 1969-05-20 | Bourdin & Chausse Sa Entrepris | Method and apparatus for determining the compactness of the surface over which a vehicle travels |
US4348901A (en) * | 1979-10-19 | 1982-09-14 | Koehring Gmbh-Bomag Division | Apparatus for monitoring the degree of compaction |
JPH03269338A (en) * | 1990-03-20 | 1991-11-29 | Sakai Jukogyo Kk | Method and device for discriminating compaction degree |
US6004076A (en) * | 1995-03-03 | 1999-12-21 | Compaction Technology (Soil) Limited | Method and apparatus for monitoring soil compaction |
US6041582A (en) * | 1998-02-20 | 2000-03-28 | Case Corporation | System for recording soil conditions |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0045026B1 (en) * | 1980-07-29 | 1985-01-16 | becker bau GmbH & Co. KG | Method for soil stabilisation |
US5105650A (en) * | 1990-03-08 | 1992-04-21 | Gas Research Institute | Monitoring compaction of backfill |
US5426972A (en) * | 1993-04-20 | 1995-06-27 | Gas Research Institute | Monitoring soil compaction |
JPH08281373A (en) * | 1995-04-14 | 1996-10-29 | Sintokogio Ltd | Method for measuring effective clay-component of green sand |
JP3269338B2 (en) * | 1995-07-24 | 2002-03-25 | 三菱自動車エンジニアリング株式会社 | Fuel supply device |
JP3318576B2 (en) * | 1995-09-20 | 2002-08-26 | 新東工業株式会社 | How to measure sand properties |
-
2001
- 2001-05-15 WO PCT/US2001/015638 patent/WO2001088529A1/en active Application Filing
- 2001-05-15 EP EP01935521A patent/EP1407262A4/en not_active Ceased
- 2001-05-15 CN CNB018234801A patent/CN100414295C/en not_active Expired - Fee Related
- 2001-05-15 AU AU2001261609A patent/AU2001261609B2/en not_active Ceased
- 2001-05-15 CA CA2447157A patent/CA2447157C/en not_active Expired - Fee Related
- 2001-05-15 AU AU6160901A patent/AU6160901A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3444727A (en) * | 1965-06-04 | 1969-05-20 | Bourdin & Chausse Sa Entrepris | Method and apparatus for determining the compactness of the surface over which a vehicle travels |
US4348901A (en) * | 1979-10-19 | 1982-09-14 | Koehring Gmbh-Bomag Division | Apparatus for monitoring the degree of compaction |
JPH03269338A (en) * | 1990-03-20 | 1991-11-29 | Sakai Jukogyo Kk | Method and device for discriminating compaction degree |
US6004076A (en) * | 1995-03-03 | 1999-12-21 | Compaction Technology (Soil) Limited | Method and apparatus for monitoring soil compaction |
US6041582A (en) * | 1998-02-20 | 2000-03-28 | Case Corporation | System for recording soil conditions |
Non-Patent Citations (3)
Title |
---|
PATENT ABSTRACTS OF JAPAN vol. 016, no. 085 (P-1319), 28 February 1992 (1992-02-28) & JP 03 269338 A (SAKAI JUKOGYO KK), 29 November 1991 (1991-11-29) * |
See also references of WO0188529A1 * |
TRITICO PHILIP A ET AL: "Practice improvements for the design and construction of clay barriers" GEOTECH SPEC PUBL; GEOTECHNICAL SPECIAL PUBLICATION 1995 ASCE, NEW YORK, NY, USA, no. 46/1, 1995, pages 624-640, XP008066784 * |
Also Published As
Publication number | Publication date |
---|---|
AU2001261609B2 (en) | 2006-02-23 |
EP1407262A4 (en) | 2006-08-23 |
CN100414295C (en) | 2008-08-27 |
CA2447157A1 (en) | 2001-11-22 |
WO2001088529A1 (en) | 2001-11-22 |
CA2447157C (en) | 2012-08-21 |
CN1529813A (en) | 2004-09-15 |
AU6160901A (en) | 2001-11-26 |
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