P, <357^5/46 JOURNAL of the AMERICAN CONCRETE INSTITUTE (ACI PROCEEDINGS Vol. 42) Vol. 17 June 1946 No. 6 CONTENTS Papers and Reports..................................................................................5 6 5 -7 2 0 Asphaltic Oil-Latex Joint-Sealing Compound. ...BRYANT W. POCOCK 565 Petrography of Concrete Aggregate................................................................... ...........................................................ROGER RHOADES and R. C MIELENZ 581 Entrained A ir in Concrete: A Symposium.......................................... 601 Entrained Air— A Factor in the Design of Concrete Mixes .............................W. A. CORDON 605 Recent’Experiences withlAir-EntraininglPortlandlCemenCConcrete in the Northeastern States ........................................................................................................................................L. E. A N D R E W S 621 Experiences with Air-Entraining Cement in Central-Mixed Concrete................................................ ALEXANDER FOSTER, Jr. 625 Studies of Concrete Containing Entrained A ir ............................................................................................. ....................................................................................STANTON WALKER and DELMAR L. BLOEM 629 Homogeneity of Air-Entraining Concrete ...............................................HENRY L. KENNEDY 641 Methods of Entraining A ir in Concrete............................................................E. W . SCRIPTURE, J r. 6 4 5 Effect of A ir Entrainment on Stone Sand Concrete..............................................A. T. GOLDBECK 649 A Method for Direct Measurement of Entrained Air in Concrete..................................................... .................................................................................................. W. H. KLEIN and STANTON WALKER 657 Automatic Dispensing Equipment for Air-Entraining Agents ........................ R. R. K A U F M A N 6 6 9 Mechanical Dispensing Devices’for ¡Air-Entraining Agents ................................E. M . BRICKETT 6 7 3 A Simple Accurate Method for DetermininglEntrained A ir in Fresh Concrete. ..................................................................................................................................................... S. W. BENHAM 677 Effect of Use of Blended Cements and Vinsol Resin-Treated Cements on Durability of Concrete ............................................................................................................................................ W . F. K E L L E R M A N N 681 Air-Entraining Concrete— Pennsylvania Department of Highways W. H. HERMAN 6 8 9 Portland-Rosendale Cement Blends G ive H igh Frost Resistance...............................B. H. WAIT 697 The Repair of Concrete: An Introduction.............. RODERICK B. Y O U N G 701 Behavior of Concrete Structures Under Atom ic Bombing— E. H. PRAEGER 709 Job Problems and Practice...................................................................................7 2 1 -7 2 4 What Kind of Cement Stucco?.............................................................................. 721 Setting Heavy Machinery on Concrete Bases....................R. R. KAUFMAN 721 Current Reviews......................................................................................................... 7 2 5 -7 3 2 News Letter............................................................................................................... 1 -1 2 SYMPOSIUM ON ENTRAINED AIR IN CONCRETE • Member­ ship Applications Increase • Who’s Who • Navy Seeks Former Sea- bees • Honor Roll • New Members • Joseph L. Duffy • Conde B. McCullough • William Johnson Henderson • to provide a comradeship in finding the best ways to do concrete work of all kinds and in spreading that knowledge ADDRESSi 7400 SECOND BOULEVARD, DETROIT 2, MICH. S1.50 per copy Extra copies to members SI .00 DISCUSSION Discussion dosed s«. JL •« Concrete Construction in the National Forests— C lifford A . Betts Lapped Bar Splices in Concrete Beams— Ralph W . Kluge and Edward C. Tuma Tests of Prestressed Concrete Pipes Containing A Steel Cylinder— Culbertson W. Ross Field Use of Cement Containing Vinsol Resin— Charles E, W uerpel Nov. JL 45 Maintenance and Repair of Concrete Bridges on the Oregon Highway System G. S. Paxson A n Investigation of the Strength of W elded Stirrups in Reinforced Concrete Beams Oreste Moretto Jan. Jl. 46 Shrinkage Stresses in Concrete— G erald Pickett Floating Block Theory in Structural A nalysis— Stanley U. Benscoter Shrinkage and Plastic Flow of Pre-Sfressed Concrete— Howard R. Staley and Dean Peabody, Jr. Proposed Minimum Standard Requirements for Precast Concrete Floor Units—ACI Committee 711 Proposed Recommended Practice for the Construction of Concrete Farm Silos—ACI Committee 714 Feb. Jl. '46 Maintenance of Heavy Concrete Structures— Minnesota Power & Light Company Practice Clay C. Boswell and Albert C. Giesecke Two Special Methods of Restoring and Strengthening Masonry Structures— J. W. Kelly and B. D. Keatts Laboratory Studies of Concrete Containing Air-Entraining Admixtures—- Charles E. Wuerpel Shrinkage Stresses in Concrete— (Part 2)— G erald Pickett Discussion closes August 1 5, 1946 Nov. Jl. '45 Should Portland Cement Be Dispersed?—T. C. Powers Apr. Jl. '46 Announcement of Proposed Manual of Standard Practice for Detailing Reinforced Con­ crete Structures— Reported by ACI Committee 315 (Discussion period w ill probably be - extended) Maintenance and Repair of Portland Cement Concrete Pavement— A. A. Anderson Curing Concrete with Sealing Compounds— R. F. Blanks, H . S. M eissner and L. H . Tuthill Radiant Heating by Reinforced Concrete— John R. Nichols The Expansion Test as a Measure of Alkali-Aggregate Reaction— R. F. Blanks and H S Meissner Concrete at Advance Bases— I. S. Rasmusson Discussion closes September 1, 1946 Asphaltic Oil-Latex Joint-Sealing Compound— Bryant W . Pocock June Jl. 46 Petrography of Concrete Aggregate— Roger Rhoades and R. C. Mielenz — continued on inside Back Cover Vol. 17—No. 6 June 1946 (Proceedings Vol. 42) JOURNAL of the AMERICAN CONCRETE INSTITUTE Published by the American Concrete Institute. The Institute was founded 1905; incorporated in the District of Columbia in 1906 as The National Association of Cement Users; the name changed 1913 by charter amend­ ment; reincorporated, with new statement of objects, August 8, 1945. The Journal is issued six times yearly in the months of January, February, April, June, September and November under the authority of the i BOARD OF DIRECTION, AM ERICAN CONCRETE INSTITUTE President HARRISON F. GONNERMAN V ice Presidents STAN TO N WALKER, ROBERT F. BLANKS Secretary-Treasurer HARVEY WHIPPLE Regional Directors PAUL W . N O R T O N H. P. BIGLER ROY R. ZIPPRODT CHARLES S. WHITNEY ALEXANDER FOSTER, JR. HERBERT J. GILKEY Directors-at-Large HARRY F. THOMSON FRANK H. JACKSON HENRY L. KENNEDY Past Presidents RAYMOND E. DAVIS MORTON O. WITHEY BEN MOREELL ROY W . CRUM DOUGLAS E. PARSONS Papers and other contributions prepared with a view dues. (A special dues rate of $3.00 per year applies lo Journal publication should be submitted in triplicate, for “ a student in residence at a recognized technical or addressed: Secretary, Publications Committee, Amer­ engineering school" and includes Journal subscription. ican Concrete Institute, 7400 Second Boulevard, De­ troit 2, Michigan. Publication of a contribution does Bound volumes 1 to 40 of PROCEEDINGS OF THE not imply the acquiescence of critics (whose advice is AMERICAN CONCRETE INSTITUTE (1905 to 1944) sought by the Committee, prior to acceptance) or of are for sale as far as available, at prices to be had on the Institute in the opinions which it expresses nor inquiry of the Secretary-Treasurer. Special prices the approval of data or practice which the contri­ apply for members ordering bound volumes in addition bution records. Institute authority attaches only to to the monthly Journal. Standards formally adopted as provided in the By- Law ^ A committee report implies merely the joint Publication address: 7400 Second Boulevard, Detroit 2, cont^ution of an appointed group. Michigan. Copyright, 1946, American Concrete In­ stitute, Printed in U S. A . Entered at the Post Office Subscription price $7 50 per year payable in advance. at Detroit, Michigan, as mail of the second class under To members. $7.50 oer >ear, included in the annual provisions of the Act of March 3,1879 the ACI JOURNAL is edited by the Secretary of the Publications Committee under the ■ ° - D B ? direction of the Committee a ) 5 § < 5 r -O co a> Q ) hmmto Ü ) ROBERT F. BLANKS a> r - O) O u* Chairman ■ — CN i/% a> <L> £ HARRISON F. GONNERMAN to (ex-officio) 5 "<« a > . ^ o a > j- <y v» U) R. D. BRADBURY a ® J-S <D aT E a * RAYMOND E. DAVIS * 8 * § vt o to o .E HERBERT J GILKEY <D - ■ — t o 0 - O = £ - _o o a > _o a> A. T. GOLDBECK E D a_o 1 Î u E 1 1 FRANK H. JACKSON 4 * ■ j : <u 5 2 W. H. KLEIN t o Ü-Û 3 3 u to . t > . STANTON WALKER < c o .2 0 aJ < *5 < RODERICK B. Y O U N G O ' S i l 00 — § o 0 ) « _ a HARVEY WHIPPLE O) _ c O a t o Secretary .■3 ■ - ( .E ° <D Æ a o O g o a ) - o E a> It is the policy of the American Concrete _ o Institute to encourage participation by its a> o . a> members and others in the work of extending u o the knowledge of concrete and reinforced a> < concrete as a basis for improved products a > * ■ and structures. cl ^ O <N 1 - O T - To this end the Board of Direction has