- 786 - SECTION 1003 -- FLOWABLE FILL
1003.01 Description
1.Flowable fill shall be a mixture of cement, fly ash, fine sand, water, and air having a consistency which will flow under a very low head.
1003.02 Material Characteristics
1.The approximate quantities of eac h material per cubic yard (cubic meter) of mixed material shall be as shown in Table 1003.01. Table 1003.01 Flowable Fill Composition Cement (Type I or II) 50 pounds/cu. yd. (30 kg/m3) Fly ash 200 pounds/cu. yd. (120 kg/m3) Fine sand 2,700 pounds/cu. yd. (1600 kg/m3) Water (approx.) 420 pounds/cu. yd. (250 kg/m3) Air content (approx.) 10%
2.Actual quantities shall be adjusted to provide a yield of 1 cubic yard (cubic meter) with the materials used.
3.Approximate compressive strength should be 85 to 175 psi (0.6 to 1.2 MPa).
4.Fine sand shall be an evenly graded material having not less than 95% passing the No. 4 sieve (4.75 mm) and not more than 5% passing the No. 200 (75 m) sieve.
5.Mixing and handling of the material shall be in accordance with Section 1002.
1003.03 Acceptance Requirements
1.Flowable fill is accepted bas ed on it meeting the requirements in this Section.
2.Cement must be on the Depar tment’s Approved Products List.
3.Fly ash meeting requirements in Section 1008 can be either Class “C” or Class “F”. - 787 - SECTION 1004 -- PORTLAND CEMENT
1004.01 Description
1.Portland cement is the binder in concrete, locking the aggregate into a solid structure. It is manufactured from lime, silica, and alumina (with a small amount of plaster or Gypsum).
2.Equivalent alkali is defined as the sum of the Sodium Oxide (Na 20) and the Potassium Oxide (K 20) calculated as Equivalent Alkali Na 20e = Na 20 + 0.658 K 20).
3.Interground and Blended cements consist of uniform intergrinding and/or blending of Portland cement clinker, Slag cement, Pozzolan and/or Limestone.
1004.02 Material Characteristics
1.Type I, Type II and Type III Portland cement shall conform to the requirements in ASTM C 150 with the following additional requirements:
a.Portland cement shall not contain more than 0.60% equivalent alkali.
2.Interground and Blended Cement shall conform to the requirements in ASTM C 595 with the following additional requirements:
a.Interground/Blended cement (Type IP) (1) For Type IP(25) shall be composed of Class F fly ash or Class N pozzolan replacement at 25% - 2%.
2.For Type IP(20) shall be composed of Class F fly ash or Class N pozzolan replacement at 20% + 2%.
b.Interground/Blended cement (Type IS) (1) For Slag Cement, the maximum replacement shall be 35% +5 when incorporated into the final Interground/Blended cement.
c.Interground/Blended cement (Type IT) (1) For Supplemental Cementitious Materials (SCMs), Slag cement and Limestone, the maximum repl acement by weight shall be 40%. The manufacturer has a production tolerance of + 2% from the proposed replacement.
2.For Limestone cement, the replacement range shall be from 5.1% to 10.0% when incorporated into the final Interground/Blended cement.
d.No additional SCMs, Slag cement and Limestone will be added at the batch plant.
1004.03 Procedures
1.The Contractor shall provide adequate protection for the Portland and Interground/Blended cement against dampness.
a.Portland and Interground/Blended cement shall be hauled or stored in railroad cars, dry bulk trailers or in suitable moisture-proof buildings.
b.The use of tarpaulins for t he protection of the Portland and Interground/Blended cement will not be allowed.
Source: Nebraska Standard Specifications for Highway Construction, 2017 Edition. Pages 820–820 of 1,048.