ACI 301 is a re f e rence standard which the engineeror architect may make applicable to any building

project by citing it in the project specifications. He sup-plements it as needed by designating or specifying indi-vidual project requirements.

How ACI 301 is used

As its introduction explains, ACI 301 is incorpora t e dinto project specifications by re f e re n c e. For example, thec o n t ract re q u i rements might read: “Co n c rete work shallc o n f o rm to all re q u i rements of ACI 301-72 (Re v i s e d1981), Specifications for St ru c t u ral Co n c rete for Bu i l d-i n g s.” If some part of ACI 301 is not appro p ri a t e, thespecifier can state any desired exc e p t i o n s.

So that the standard is not confused with an earliers t a n d a rd or an earlier revision, the year the standard wasadopted and the last year it was revised must be includ-ed when re f e rencing it. ACI 301 was adopted as a stan-d a rd by the American Co n c rete Institute in May 1972and most recently revised in May 1981.

Supplementary requirements briefly added

ACI 301 is not complete in itself, though. The re q u i re-ments that va ry from project to project must be speci-fied. A list of such re q u i rements is presented at the be-ginning of ACI 301. Two of these re q u i rements must bespecified for all pro j e c t s :• the strength of the concrete for each portion of the

s t ru c t u re

• the types and grades of re i n f o rcing steelOther supplemental re q u i rements are designated on-

ly when they apply. Some examples are: the test age ofc o n c rete if other than 28 days; the admixtures that arere q u i red or prohibited; the types and strengths of pre-s t ressing steel; and when re s h o ring is re q u i red or per-m i t t e d .

It takes the specifier only about three pages to statethe mandatory supplementary re q u i re m e n t s — c o n c re t es t rength and type of re i n f o rcement—plus those supple-m e n t a ry re q u i rements that pertain to the specific pro-ject. The list of supplementary items at the beginning ofACI 301 serves as a checklist; each item is keyed to sec-tion numbers in the text.

Notes help contractor

At the end of each chapter are notes pointing out anyitems which re q u i re approval of the arc h i t e c t - e n g i n e e ror other specifying authori t y. Items such as constru c t i o njoints not shown on the dra w i n g s, pro p ri e t a ry patchinga g e n t s, or heavy-duty toppings are among those calledout. It is virtually impossible to overlook these sensitivep o i n t s. They can be found by quick inspection at the endof the chapters instead of having to scan the entire doc-u m e n t .

What ACI 301 covers

This 36-page re f e rence standard is divided into 18chapters (see box). Each chapter is further divided intosections and subsections. Decimal numbering makes foreasy re f e rence and shows the relationship of topics.

Why reference ACI 301?

The re q u i rements of ACI 301 are standard specifica-t i o n s, developed through a consensus process and ap-p roved by a group of industry pro f e s s i o n a l s. If followe dc o r re c t l y, these specifications will produce quality con-s t ruction. With repeated use, they become familiar, notf rightening. The contractor comes to know what the

ACI 301–Specifications for Structural Concrete for BuildingsA reference standard good for both specifier and contractor

OTHER ACI REFERENCE SPECIFICATIONS

ACI 301 is a specification for stru c t u ral concrete inb u i l d i n g s. It focuses on basic cast-in-place work and doesnot deal with specialty concre t e s. Some other re f e re n c especifications available from ACI include the follow i n g :

5 0 3 . 1 - 7 9 Bonding Ha rdened Co n c re t e, Steel, Wood, Brick, and Other Ma t e rials to Ha rdened Co nc rete with a Multi-component Ep oxy Ad h e s i ve

503.2-79 Bonding Plastic Co n c rete to Ha rdened Co nc rete with a Multi-component Ep oxy Ad h e s i ve

5 0 3 . 3 - 7 9 Producing a Sk i d - resistant Su rface on Co n c re t eby the Use of a Multi-component Ep ox ySy s t e m

503.4-79 Re p a i ring Co n c rete with Ep oxy Mo rt a r s

3 3 6 . 1 - 7 9 End Be a ring Drilled Piers

3 4 6 - 8 1 Cast-in-place No n re i n f o rced Co n c rete Pipe

5 0 6 . 2 - 7 7 Ma t e ri a l s, Pro p o rtioning, and Application of Sh o t c re t e

531.1-76 Co n c rete Ma s o n ry Co n s t ru c t i o n

For more information, contact the American Co n c re t eIn s t i t u t e, Box 19150, De t roit, Michigan 48219.

s t a n d a rd says. He does not have to wade through thee n t i re concrete specification to avoid surpri s e s.

Re f e rencing ACI 301 saves the specifier time in wri t-ing the project specifications. The contractor can be-come familiar with the standard in advance and alsos a ve time. As long as ACI 301 is not re w ritten or re t y p e d ,the contractor can assume he knows the perf o rm a n c el e vel re q u i red and read only the supplemental re q u i re-ments and those parts he needs to re v i e w. On the otherhand, if the complete standard we re entered into a wordp rocessor and neatly printed out in the contract docu-

m e n t s, the bidder would still have to re read the materi-al closely to be certain no changes we re made—by acci-dent or intention. ACI 301 thus saves time for both thespecifier and the contra c t o r, particularly when incor-p o rated by re f e re n c e.

Co pying the standard is not necessary anyway. Se c-tion 1.6 of ACI 301 re q u i res the contractor to keep atleast one copy of the ACI Field Re f e rence Manual, SP-15( 8 1 ) , in his field office at all times. The field manual con-tains ACI 301 and other selected ACI and ASTM re f e r-e n c e s. Published by the American Co n c rete In s t i t u t e,

SUBJECTS COVERED IN AACI 301 CHAPTERS

1–GENERAL: Defines certain words used inACI 301 and lists ASTM and other standards cit-ed in ACI 301.

2 – M ATERIALS FOR CONCRETE: Re f e re n c e sASTM standards for materials and tells how ma-t e rials should be store d .

3 – P RO P O RTIONING: Three methods basedon (1) trial mixes, (2) past field test data, and (3)ac h a rt indicating maximum water-cement ra t i o,and slump are specified. Chart classifies con-c rete floors by use and gives minimum stre n g t hand maximum slump for each.

4 – F O R M WORK: Design and installation off o rm w o rk: pre p a ration of form surfaces; re-m oval of forms; and re s h o ring. Chart lists toler-ances for va rious formed surf a c e s.

5 – R E I N F O RC E M E N T: Co n c rete cover over re-i n f o rcement; overlap of wire fabric re i n f o rc e-ment; supporting and fastening re i n f o rc e m e n t ;and tolerances in fabrication rebar placement.ASTM specifications are re f e re n c e d .

6 – J O I N TS AND EMBEDDED ITEMS: Locationand construction of joints; methods for bondingjoints; types of expansion joint filler. Re q u i re-ments for waterstops and placing embeddedi t e m s.

7 – P RODUCTION OF CO N C R E T E : Re q u i re-ments for batching and mixing, for pro d u c i n gl i g h t weight concre t e, and for adding admixture sand mix water. Cites ASTM standards for re a d ymixed concrete and for concrete produced byon-site vo l u m e t ric batching and continuousm i x i n g .

8 – P LACING: Method of vibration, limits onplacing tempera t u re and pre p a ration of jointsfor bonding. Gi ves re q u i rements for truck mix-e r s, belt conve yo r s, chutes, and pumping equip-m e n t .

9 – R E PAIR OF SURFACE DEFECTS: How top re p a re the surface and mix grout and patchingc o m p o u n d .

10–FINISHING OF FORMED SURFAC E S :Methods for as-cast finishes and rubbed finish-es such as grout cleaned or cork floated.

1 1 – S LABS: Co n s t ruction of two-course slabsand how to do the following finishes: scra t c h e d ,floated, troweled, broom or belt, dry shake, ex-posed aggre g a t e, and non-slip.

12–CURING AND PROTECTION: How andh ow long to cure. Pro t e c t i ve measures againstwind and hot or cold tempera t u re s.

13– ARCHITECTURAL CO N C R E T E : L o c a t i o nof joints and form ties; form deflections allowe d ;and the re q u i rements for pro p o rtioning mixes,patching surf a c e s, and forming arc h i t e c t u ra lf i n i s h e s.

14–MASSIVE CO N C R E T E : Ma t e rial, pro p o r-tioning, placing, curing and protection re q u i re-m e n t s.

15–PRESTRESSED CONCRETE: Definition ofp re s t ressing terms; re q u i rements for tendons,a n c h o ra g e s, couplings, sheathing, and gro u t .Methods for placing and protecting tendons,applying pre s t ressing forc e, and gro u t i n g .

16–TESTING: Which tests must be made andh ow often to make them. Who makes tests, andwho pays for them.

1 7 – EVA LUATION AND ACC E P TANCE OFCONCRETE: Va riation allowed in concrete tests t rengths; use of in-place testing, especially coret e s t s.

1 8 – ACC E P TANCE OF STRUCTURE: Di m e n-sional tolerance and appearance necessary.Conditions which might impair the strength of as t ru c t u re.

the manual costs $21.50 to ACI members and $28.50 ton o n m e m b e r s. ACI also makes copies of ACI 301 suitablefor binding into project specifications.

How ACI 301 relates to the ACI 318 BuildingCode

Un f o rtunately some specifiers incorporate ACI 318by re f e re n c e, instead of using ACI 301. This is not goodp ra c t i c e. ACI 318, “Building Code Re q u i rements for Re-i n f o rced Co n c re t e,” is written so it may be adopted byre f e rence in a general building code. It is intended aspublic law, not a specification.

Though compatible and consistent with ACI 318, AC I301 is different. While ACI 318 presents minimum re-q u i rements for public safety, ACI 301 presents above -minimum construction re q u i re m e n t s. Fo l l owing AC I318 guarantees safe design, not good constru c t i o n .Specifiers should there f o re re f e rence 301, not 318. Re f e r-encing 318 may tend to make the contractor re s p o n s i b l efor design questions which should be handled by thea rc h i t e c t - e n g i n e e r.

PUBLICATION #C830451Co py right © 1983, The Ab e rdeen Gro u pAll rights re s e rve d