Section 701 - Portland Cement Concrete for Structures

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2012 Standard Specifications for Construction
Section 701
Portland Cement Concrete for Structures


UNOFFICIAL TEST VERSION
This version of this document is not intended to be used as reference in any legal matter. For the official version, please refer to the 2012 Standard Specifications for Construction - Section 701.

Contents

701.01. Description

This work consists of producing and furnishing concrete proportioned for the grades of concrete required.

The term “sack” refers to a 94-pound sack of cement.


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701.02. Materials

Provide materials in accordance with the following:

Material Section
Cement 901
Slag Cement 901
Fly Ash 901
Coarse Aggregate 6A, 6AA,17A 902
Fine Aggregate 2NS, 2SS 902
Concrete Admixtures 903
Water 911

Provide coarse aggregate in accordance with Table 701-1A and Table 701-1B for the specified concrete grade.

Provide stone sand 2SS only for structure concrete not exposed to vehicular traffic.

Do not use concrete accelerators that contain calcium chloride in concrete for bridges or concrete with embedded aluminum or galvanized steel.


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701.03. General Requirements

A. Structural Concrete Mixtures

Provide concrete mixtures in accordance with:
1. Batch plant equipment, certification, and certification waiver requirements of subsection 601.03.A, subsection 601.03.B, and subsection 601.03.C, respectively;
2. Materials handling requirements of subsection 601.03.D;
3. Concrete mixing requirements of subsection 601.03.E; and
4. Concrete temperature requirement of subsection 601.03.F.1.

B. Concrete Quality Control

Provide concrete Quality Control (QC) in accordance with section 604 and the contract. Unless otherwise specified in the contract, provide concrete structure mixtures in accordance with Table 701-1A and Table 701-1B. Use supplemental cementitious materials as specified in the contract.

C. Air Content of Structural Concrete

Do not use de-foaming (air- detraining) admixtures. Furnish concrete containing 5.0 to 8.0 percent entrained air, except as follows:
1. Provide an entrained air content of 5.5 to 8.5 percent for concrete containing Type F or Type G admixtures;
2. Air content less than 5.5 percent for concrete that lies in the finished work at least 3 feet below the surface of the ground or entirely under water will not be cause for rejection; and
3. The Engineer will allow non-air-entrained concrete for concrete placed in steel shell piles not subject to freezing.
Use the Department’s modification of ASTM C 231 or ASTM C 173 to determine the air content of freshly mixed concrete. Take samples according to MTM 207.
Use the volumetric method, ASTM C 173 to determine the air content of freshly mixed concrete containing highly porous coarse aggregate. Take samples according to MTM 207.
If the proportion of air entraining admixture used is adjusted, record the new quantity on the first delivery ticket following the adjustment.
If concrete having low air content arrives at the project site in truck mixers, additional air-entraining admixture may be added at the site, with additional mixing as necessary, until adjustments at the batching plant are made.

D. Work Progress Specimens for Structure

Ensure that the strength of structure concrete meets the requirements of subsection 104.11.B for opening to construction traffic or vehicular traffic, removing shoring or forms, or similar operations. Test work progress specimens in accordance with subsection 601.03.H.


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701.04. Measurement and Payment

The cost of producing and furnishing structure concrete mixtures is included in the unit prices for other relevant pay items.


Table 701-1A

Concrete Structure Mixtures by Slump

Concrete

Grade

(e, h)

Section Number

Reference

(i)

Cement content

per cubic yard

(b, c)

Slump (in)

Type A, D

or no

Admixture

Type MR, F, or G Admixtures

(g)

lb

sack

Before

Admixture

After Admixture

(Type MR)

After Admixture

(Type F or G)

D (a)

706, 711, 712

658 (d)

7.0

0 – 3

0 – 3

0 – 6

0 – 7

S1

705

611

6.5

3 – 5

0 – 3

3 – 6

3 – 7

T

705, 706

611

6.5

3 – 7

0 – 4

3 – 7

3 – 8

S2 (a)

401, 705, 706, 712,

713, 801, 802, 803, 810

564

6.0

0 – 3

0 – 3

0 – 6

0 – 7

526 (d)

5.6

S3

402, 403, 803, 804, 806

517

5.5

0 – 3

0 – 3

0 – 6

0 – 7

489 (d)

5.2

Note: See below for table notes.


Table 701-1B

Concrete Structure Mixtures by Strength of Concrete

Concrete

Grade

(e, h)

Section Number

Reference

(i)

Cement content

per cubic yard

(b, c)

Minimum Strength of Concrete

(f)

lb

sack

Flexural, (psi)

Compressive, (psi)

7 day

14 day

28 day

7 day

14 day

28 day

D (a)

706, 711, 712

658 (d)

7.0

625

700

725

3,200

4,000

4,500

S1

705

611

6.5

600

650

700

3,000

3,500

4,000

T

705, 706

611

6.5

550

600

650

2,600

3,000

3,500

S2 (a)

401, 705, 706, 712,

713, 801, 802, 803, 810

564

6.0

550

600
650

2,600

3,000

3,500

526 (d)

5.6

S3

402, 403, 803, 804, 806

517

5.5

500

550

600

2,200

2,600

3,000

489 (d)

5.2

Note: See below for table notes.


Notes for Table 701-1A and Table 701-1B:

a. Unless otherwise required, use Coarse Aggregate 6AA or 17A for exposed structural concrete in bridges, retaining walls, and pump stations.

b. If the local average minimum temperature for the next 10 consecutive days after concrete placement is forecast to be below 40 °F, submit a revised quality control plan for the Engineer’s approval prior to cold weather concrete placement. The revised plan must detail changes in materials, concrete batching and mixing processes, construction methods, curing, and protection of the in situ concrete to ensure that the quality characteristics of the hardened concrete are not compromised by the cold weather. The restriction does not apply to Grade S1 concrete in foundation piling below ground level or Grade T concrete in tremie construction.

c. Type III cement is not permitted.

d. Use admixture quantities specified by the Qualified Products Lists to reduce mixing water. Admixture use is required for Grade D, Grade S2, and Grade S3, concrete with a reduced cement content. Use a water-reducing retarding admixture at the required dosage for Grade D concrete to provide the setting retardation required. When the maximum air temperature is not forecast to exceed 60 °F for the day, the Contractor may use a water-reducing admixture or a water-reducing retarding admixture. Ensure Grade D concrete in concrete diaphragms contains a water-reducing admixture, or a water-reducing retarding admixture. For night casting, the Contractor may use a water-reducing admixture in lieu of water-reducing retarding admixture, provided that the concrete can be placed and finished prior to initial set.

e. The mix design basis for bulk volume (dry, loose) of coarse aggregate per unit volume of concrete is 68% for Grade S1, and 70% for Grade D, Grade S2, Grade T, and Grade S3 Footnote e does not apply to mix designs containing Engineer-approved, optimized aggregate gradations.

f. The Contractor may use flexural strength to determine form removal. Use compressive strength for acceptance in other situations.

g. MR = Mid-range.

h. The Engineer will allow the use of an optimized aggregate gradation meeting the requirements of MTM 130.

i. Section Number Reference

Section Number Reference

401

Culverts

402

Storm Sewers

403

Drainage Structures

705

Foundation Piling

706

Structural Concrete Construction

711

Bridge Railings

712

Bridge Rehabilitation-Concrete

713

Bridge Rehabilitation-Steel

801

Concrete Driveways

802

Concrete Curb, Gutter and Dividers

803

Concrete Sidewalk, Sidewalk Ramps, and Steps

804

Concrete Barriers and Glare Screens

806

Bicycle Paths

810

Permanent Traffic Signs and Supports


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