Section 4 — Structures and Foundations

Concrete Design

IPE Engineering Practice IPE-EP-4-3-1

Document number: IPE-EP-4-3-1 · Section: 4 — Structures and Foundations

SCOPE

This Practice covers requirements for the design of reinforced concrete for foundations, buildings, and all other structures.
Requirements for concrete construction and concrete reinforcement fabrication are covered in EP 4-3-2 and EP 4-3-3, respectively.
Any deviation to this Practice must be approved by the procedure described in EP 1-1-3.
An asterisk (*) indicates that a decision or approval by the Owner or the Owner's Engineer is required, or that additional information is furnished by the Purchaser.
A revision bar indicates all changes made to this Revision.
Documentation required in accordance with this Practice is given in Table 2.

2.0 REFERENCES

The latest edition of the following Standards and Publications are referenced herein.

STANDARDS AND PUBLICATIONS

IPE Engineering Practices
EP 1-1-3 Deviations to IPE Engineering Practices EP 4-1-1 Design Criteria and Loads for Structures EP 4-2-3 Reinforced Concrete Foundations EP 4-3-2 Concrete Construction Requirements EP 4-3-3 Concrete Reinforcement Fabrication EP 4-4-1 Roadways and Paving
ACI Standard
211 Standard Practice for Selecting Proportions for Concrete 313 Recommended Practice for Design and Construction of Concrete Silos, Bins and Bunkers for Storing Granular Materials 315 Manual of Standard Practice for Detailing Reinforced Concrete Structures 318 Building Code Requirements for Reinforced Concrete
ASTM Standards
A82 Cold-Drawn Steel Wire for Concrete Reinforcement A185 Welded Steel Wire Fabric for Concrete Reinforcement

STANDARDS AND PUBLICATIONS (CONTINUED)

ASTM Standards (Continued)
A615 Deformed and Plain Billet Steel Bars for Concrete Reinforcement C31 Making and Curing Concrete Test Specimens in the Field C33 Concrete Aggregates C109 Test Method for Compressive Strength of Hydraulic Cement Mortars C150 Portland Cement C192 Making and Curing Concrete Test Specimens in the Laboratory C260 Air-Entraining Admixtures for Concrete C494 Chemical Admixtures for Concrete C618 Fly Ash and Raw or Calcined Natural Pozzolan for Use as a Mineral Admixture in Portland Cement Concrete
CRSI Practice
MSP-2-81 Manual of Standard Practice

DEFINITIONS

Contractor - Company or business that agrees to furnish materials or perform specified services at a specified price and/or rate to the Owner.
Inspector - A Inflection Point Engineering, LLC appointed engineer or inspector.
Manufacturer - The recipient of a direct or indirect purchase order for materials and/or equipment. In this context, a direct order is one issued to a manufacturer by a contractor or the Owner. An indirect order is one issued to a manufacturer by a vendor (recipient of a direct order) for materials, fabricated components, or subassemblies.
Moderate Sulfate Service - 0.10 to 0.20% water soluble sulfate (SO4 ) in soils or 150 to 1,500 ppm sulfate (SO4 ) in solution.
Non-Sulfate Service - Less than 0.10% water-soluble sulfate (SO4 ) in soils or less than 150 ppm sulfate (SO4 ) in solution.
Owner - Inflection Point Engineering, LLC.
Owner's Engineer - A Inflection Point Engineering, LLC appointed engineer.
Purchaser - The party placing a direct purchase order. The purchaser is the Owner's designated representative.
Severe Sulfate Service - 0.20 to 2.0% water-soluble sulfate (SO4 ) in soils or 1,500 to 10,000 ppm sulfate (SO4 ) in solution

MATERIALS

ACI 211 shall be consulted in the proportioning of concrete mixes.

Cement
(*)Unless otherwise specified by the Owner's Engineer, ASTM C150 Type I Portland cement shall be used in non-sulfate service. See Section 3.0 of this Practice.
ASTM C150 Type II Portland cement shall be used in moderate sulfate service. See Section

3.0 of this Practice.

ASTM C150 Type V Portland cement shall be used in severe sulfate service. See Section 3.0 of this Practice.
(*)If greater than 2.0% water-soluble sulfate in soils or greater than 10,000 ppm sulfate in solution is present, pozzolan shall be added to Type V cement. The amount and type of pozzolan shall be determined by tests of the cement's sulfate resistance, and shall be approved by the Owner.
(*)Type Ill, high-early strength concrete shall be used only when approved by the Owner's Engineer.
(*)Admixtures shall be used only when specified by the Owner, and shall satisfy the additional requirements of this Paragraph.
(*)Air-entraining admixtures shall conform to ASTM C260. The amount of air to be used in air- entrained concrete depends on many factors and shall be specified by the Owner.
Water-reducing, retarding, accelerating and combination admixtures shall conform to ASTM C494.
Fly ash or pozzolan used as admixtures shall conform to ASTM C618.
Aggregate for concrete shall conform to ASTM C33 and the following requirements:
(*)Fine aggregate shall be high-silica sand, unless otherwise approved by the Owner.
(*)Coarse aggregate shall be crushed rock or siliceous gravel. Limestone shall not be used unless approved by the Owner. The Purchaser shall specify the size of aggregate.
Water used in concrete shall be clean and free from injurious amounts of oils, acids, alkalis, salts, organic materials or other substances deleterious to concrete or carbon steel. Non- potable water shall not be used in concrete unless the following are satisfied:
Proportioning of the concrete is based on mixes using water from the same source.
Mortar test cubes made with the non-potable water and tested per ASTM C109 exhibit 7 and 28 day strengths of at least 90% of strengths of similar specimens made with potable water.
(*)Dyes shall be added to concrete only when specified by the Purchaser. Type and amount of dye, when added, shall be specified by the Owner's Engineer.
The contractor shall document all materials (cement, aggregate, and any admixtures) used in the mix, as well as the average compressive strength of the concrete.
Metal Reinforcement for Concrete

All materials shall be new and free from loose or flaky rust, mill scale, grease, oil, mud, or any other coating which would reduce or destroy the bond to concrete.
(*)Metal reinforcement shall be Grade 60 deformed bars conforming to ASTM A615, unless otherwise specified.
Plain steel wire for spiral reinforcement shall conform to ASTM A82 with a minimum yield strength of 70,000 psi.
Welded plain wire fabric shall conform to ASTM A185 with a minimum yield strength of 65,000 psi.
(*)Reinforcement supports shall be standard types and sizes given in Chapter 3 of CRSI MSP- 2-81. Unless otherwise specified by the Owner, materials shall be selected based on the three classes of protection given in CRSI MSP-2-81.

DESIGN

Concrete design for building and pipe support structures shall be in accordance with ACI 318 and the additional requirements of this Practice.
(*)Pre-stressed or post-tensioned concrete shall not be used unless approved by the Owner.
The design of concrete silos, bins and bunkers for storing granular materials shall be in accordance with ACI 313 and the additional requirements of this Practice.
The design of reinforced concrete foundations shall be in accordance with EP 4-2-3 and the additional requirements of this Practice.
Concrete pavements shall be designed in accordance with EP 4-4-1 and the additional requirements of this Practice.
(*)Concrete design details shall be prepared in accordance with ACI 315. Plan, elevation, and detail drawing required for the construction of a concrete structure shall be submitted to the Owner's Engineer.
Design loads for concrete structures shall be in accordance with EP 4-1-1.
(*)Unless otherwise specified by the Owner, concrete shall have a minimum compressive strength per Table 1. The values shown in Table 1 represent 28-day compressive strength of normal Portland cement concrete, or 7-day compressive strength of high-early strength concrete, as determined by tests on 6-inch diameter by 12-inch high cylinders per ASTM C192, ASTM C31 and EP 4-3-2.
All steel shall be galvanized when surfaces will be exposed after the concrete is finished.

6.0 TABLES

TABLE 1

APPLICATION AND COMPRESSIVE STRENGTHS OF CONCRETE

APPLICATION	COMPRESSIVE STRENGTH psi
Prestressed piling exposed to sea water	5,000
Prestressed and precast concrete structures Precast piling	4,000
Precast pipe Precast concrete sills, copings, and all ornamental concrete Reinforced concrete chimneys Foundations for tanks in sulfuric acid service Concrete structures in continuous contact with sea water Reservoirs and separators	3,500
Girders, beams, walls, slabs, piers, and columns Superstructure for docks and bridges Concrete structures over sea water Pipe supports Concrete for fireproofing Concrete on or below grade: such as footings, pile caps, tank foundations, tie beams, grade beams, anchor blocks, pump blocks, catch basins, manholes, sidewalks, and paving (1) Cast-in place piling (land use) (1)	3,000
Concrete for underground electrical (protective cover, etc.)	2,000
Low-strength concrete for filling purposes where mass, rather than strength, is the principal requirement	1,500

NOTE:

(1) Concrete exposed to moderate sulfate attack.

TABLE 2

DOCUMENTATION REQUIREMENTS FOR CONCRETE DESIGN PER EP 4-3-1

Item	Description	Format	As-Built
1	Specification of materials used in concrete mixtures.	Text	N/A
2	Plan, elevation and detail drawings required for the concrete structures.	See EP 2-5-2	Yes

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