- 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.
1004.03 Portland Cement
- 788 - 2. No Portland and Interground/Blended cement which has become caked or lumpy shall be used.
3.Portland and Interground/Blended cement which has been spilled shall not be used.
4.Accepted Portland and Interground/Blended cement which has been held in storage at the concrete mix plant more than 90 days shall be retested.
5.Portland and Interground/Blended cement coming directly from the manufacturer shall not be used until it s temperature is 150°F or less.
6.Portland cement having false set when tested in accordance with ASTM C 150 will not be used.
1004.04 Acceptance Requirements
1.Portland and Interground/Blended cements shall be on the Department’s Approved Products List (APL).
2.The Contractor shall s ubmit any new Portland and Interground/Blended cements to the Engineer to be approved for the APL with the following:
a.Material source information: (1) Mill Location (2) Type of Portland and Interground/Blended cements (3) Grinding Period (4) Associated Ma nufacture Product Name
5.Provide source and type of each SCMs and/or Slag Cement used for final product.
i.The Department will allow the use of ASTM C 1697. (a) When two or more SCMs and/or Slag Cement are pre-blended, the Cont ractor shall report chemical composition analysis of the final blend.
b.The final blend shall be reported as per ASTM C 1697, Paragraph 4.
6.Portland cement shall conform to ASTM C 150. (7) Interground/blended cements shall conform to ASTM C 595.
8.Provide total cementitious materials replacement per ASTM C 595.
9.Report test results per ASTM C 1567 at 28-days.
3.Alkali Silica Reaction Requirements and Testing: a. Interground/Blended cement shall be tested according to the provisions of ASTM C 1567.
1.The mortar bars shall be composed of Type IP, IS or IT Interground/blended cement and sand and gravel from an approved Platte River Valley-Saunders County source. Portland Cement 1004.05 - 789 - (i) When Elkhorn River-Madison County source or an out of state aggregate source is being used on a project, the Elkhorn River or an out of state aggregat e source shall be used in lieu of the Platte River Valley- Saunders County source. (ii) When Contractor proposes a change of aggregate source, then the new aggregate source shall be tested by ASTM C 1567.
2.The mortar bars for the ASTM C 1567 shall not exceed 0.10% expansion at 28 days.
4.Portland and Interground/Blended cements will be placed on the Department’s Approved Products List based on the conformance with the Department’s Acceptance Policy for Portland and Interground/Blended Cements.
1004.05 Sampling and Testing Requirements
1.All Portland and Interground/Blended cements shall be sampled and tested at the rate described in the Department’s Materials Sampling Guide.
a.The Department will inform the Contractor when a sample is required.
b.A sample shall be taken by a Contractor’s Certified Portland Cement Sampler and must be under the supervision of Department certified personnel.
c.The sample shall be taken at the plant from a bulk shipment of a rail car, dry bulk trailer, batch plant silo or from the line between the bulk truck and the silo. Upon sampling, the Department will take immediate custody of the sample.
2.Noncompliant material shall be tested in accordance with ASTM C 1567 and in accordance with Section 1004.04, Paragraph 3.a. (1).
a.The mortar bars for the ASTM C 1567 shall not exceed 0.10% expansion at 28 days.
b.If the expansion is greater than 0.10% at 28 days, then the Interground/Blended cement shall be subject to removal, 40% pay and/or removal from the Department’s APL in accordance with Department’s Acceptance Policy on Portland and Interground/Blended Cements.
3.Noncompliant material from the mill, terminal or project will be temporarily removed from the Approv ed Products List pending further investigation.
4.If the noncompliant Portland or Interground/Blended cement is removed from the Department’s Approv ed Products List, all shipments from the supplier will be held until the inve stigation of the failing samples have been completed by the Department’s Materials and Research Division. - 790 - SECTION 1005 -- WATER FOR CONCRETE
1005.01 Description
1.Water shall be free from objectionable quantities of oil, acid, alkali, salt, organic matter, or other deleterio us materials and shall not be used until the source of supply has been approved.
2.Wash water from the mixer washout may be used only with the Engineer’s approval. Use of wash water will be discontinued if undesirable reaction with admixtures or aggregates occurs.
1005.02 Material Characteristics
1.Water which contains more than 0.25% total solids by weight shall not be used.
2.When required by the Engineer, the quality of mixing water shall be determined by NDOT C 114, NDOT T 290, NDOT D 512, NDOT C 1602, ASTM C 31, ASTM C 109, ASTM C 191, and ASTM C 1603.
3.Upon written request by the concrete producer and approval by Engineer, the concrete producer may utilize up to 10% wash water for batching all classes of concrete with the following conditions:
a.Wash water conforms to requirements in Paragraph 2 of Subsection 1005.02.
b.Wash water must be clarified wash water that has been passed through a settling pond system.
c.Wash water must be scalped off of a settling basin that has been undisturbed for a minimum of 12 hours.
d.Wash water must be metered into each load.
e.Wash water quantities shall be shown on the batch ticket.
Source: Nebraska Standard Specifications for Highway Construction, 2017 Edition. Pages 821–823 of 1,048.