address all of the testing requirements for the section as specified. 40
219.05 Storage and Handling Storage and handling shall be in accordance with 215.04. 219.06 Weather Limitations
Weather limitations shall be in accordance with 215.05.
219.07 Preparation of Soils Soil preparation shall be in accordance with 215.06. All rocks greater than 2 in.
encountered before or after mixing the soils and chemical modifiers shall be removed. 50 When stabilization of foundation soils with cement is required in a cut or at-grade section, the top 12 in. of soil for cement stabilized subgrade soil shall be removed and stockpiled prior to constructing the 14 in. thick stabilization of foundation soils with cement. When the stabilization of foundation soils with cement is complete, the 12 in. of cement stabilized subgrade soil shall then be placed. When stabilization of foundation soils with cement is required in a fill section, it shall be constructed prior to placement of the 12 in. of soil for cement stabilized subgrade soil. 60
219.08 Spreading and Mixing of Cement
Spreading of cement shall meet the requ irements of 215.07. The soil, cement, and water shall be in accordance with 215.08. Cement, soil, and water shall be mixed using a power-driven transverse type mixer equipped with a computer controlled volumetric water readout. Mixing shall continue until the cement is thoroughly incorporated into the soil and the mixed materials are a uniform color. Water shall be added in sufficient quantity to hydrate the cement. Water shall be introduced through the mixer to bring the mixed material 70 to at least optimum moisture content. One hundred percent of the material, exclusive of rock particles, shall pass a 1 in. (25 mm) sieve and at least 80% shall pass a No. 4 (4.75 mm) sieve. Water shall not be added when the moisture content of the soil exceeds 3% above optimum moisture conten t. The mixing and compaction shall be completed once the water has been added to the mixture. The mixing depth shall be 12 in. The moisture content shall be determined during soils cement mixing in accordance with ITM 506. 219.09 Compaction Compaction of the mixture shall begin as soon as practicable after mixing and 80 shall be in accordance with 203 or 207.03 as applicable. Compaction after mixing shall be completed within 1 h of portland ce ment placement and grading, and final compaction shall be completed within 3 h after mixing. 219.09 Initial compaction equipment shall consist of a vibratory tamping-foot roller. Final compaction shall be performed with a smooth drum roller.
219.10 Trimming Stabilized soil shall be prepared, and adequate drainage shall be provided at all 90
times to prevent water from standing on the subgrade. The grade and cross-section of the subgrade shall be finished within a tolerance of 1/2 in. from the subgrade elevation shown on the plans. Even though the subgrade has been prev iously accepted, the condition of the subgrade shall be in accordance with 105.03 and 207.04 at the time paving material is placed. Finishing within this tolerance by blading or other mechanical means without the use of side forms will be allowed. If these methods do not finish within this tolerance, 100 side forms shall be used. 219.11 QC Testing QC testing shall be performed as follows:
a.QC testing for compaction of cement stabilized subgrade soils shall be performed on the finished grade with an LWD in accordance with 203.24(b) with the exception that the interval for LWD testing shall be every 1,000 sq yds. Testing for the cement stabilized subgrade soils shall begin seven days after compaction. Construction traffic 110 or equipment exceeding 5 t in weight shall not be allowed on the treated soils until the area has passed LWD testing.
b.Moisture testing of soil cement mixtures shall be performed in accordance with ITM 506 at every 1,000 sq yds during cement and soils mixing.
c.One gradation test shall be performed for every 1,000 sq yds of cement modified soil. Gradation tests shall be performed in accordance with ITM 516. 120
d.Two test specimens shall be prep ared at 95% of the Standard Proctor and cured for seven days. Specimens shall be taken every 1,000 ft of length by lane width and shall be obtained by the Contractor. Unconfined compressive strength tests shall be performed in accordance with AASHTO T 208. The sample of the cement stabilized soils mixture shall be taken during pulverization and mixing. 219.10 261 (e) Cement spread rate shall be checked at every 2,000 ft of length by 130 lane width. Spread rate shall be in accordance with ITM 516.
f.The soil cement mixing depth shall be checked at every 2,000 ft of length by lane width in accordance with ITM 516 after mixing and prior to compaction.
g.All tests performed by the Contractor shall be compiled and submitted to the Engineer on a weekly basis for documentation of strengths obtained.
219.12 Quality Assurance, QA, Testing Moisture tests based on ITM 506 for soil cement mixtures will be performed at
every 2,000 sq yds during cement and soils mixing. Acceptance testing for compaction of ce ment stabilized subgrade soils will be performed on the finished grade with an LWD in accordance with 203.24(b) with the exception that the interval for LWD testing will be every 2,000 sq yds. The acceptance test for the cement stabilized subgrade soils will begin seven days after compaction. The allowable average deflection and maximum deflection for cement stabilized 150 subgrade soil shall be in accordance with the following: Material Type Allowable Average Deflection (mm) Maximum Deflection at Single Test Location (mm) Cement Stabilized Subgrade Soil 0.14 0.17
219.13 Curing The surface shall be maintained in a moist condition with no visible dry areas for
the first seven days after mixing with cement. Liquid membrane forming compound shall be applied in accordance with 504.04(a) to the surface and reapplied as applicable for the first seven days to aid in curing and prevent loss of moisture. 219.14 Proofrolling 160 The entire stabilized soil shall be proofrolled in accordance with 203.26. Deflection or ruts greater than 1/4 in. shall be corrected as directed.
219.15 Method of Measurement
The accepted cement stabilized subgrade soil will be measured by the square yard, complete in place.
219.16 Basis of Payment
The accepted quantity of cement stabilized subgrade soil will be paid for at the contract unit price per square yard. 170 219.16 262 Approved adjustments for cement that exceed the limit of 219.04 will be included in a change order for materials only and paid for as additional cement for subgrade soil stabilization. Payment for additional cement for subgrade soil stabilization will be made for direct delivered material costs incurred by the Contractor and will not include any other markups. Payment will be made under: Pay Item Pay Unit Symbol 180 Cement Stabilized Subgrade Soil ............................................. SYS The cost of performing mix design, services of a qualified geotechnical consultant, scarification of the soil, spreading and mixing of the cement and soil, compaction of the resultant mixture, shaping the soil, work required due to adjustments of modifier proportioning, work required due to weather conditions, correction of deficient areas, water required for the stabilization process, soil trimming, liquid membrane forming compound, and all operations needed to meet the requirements of this specification shall be included in the cost of the pay item. 190 219.16 263 DIVISION 300 – AGGREGATE PAVEMENT AND BASES
Source: Indiana Standard Specifications, 2024 Edition. Pages 276–279 of 1,248.