Chapter XVI SEWERS SPECIFICATIONS COMMITTEE-1925 F. R. ALLEN, Chairman... Pine Bluff, Ark .Long Island City, N. Y. COMMITTEE REPORT Your Committee on Sewers carrying out the program as outlined by the Society held a meeting Tuesday afternoon, October 27, in Parlor I of the Hotel Fort Des Moines. The entire membership of the Committee was in attendance and in addition there were present T. Chalkley Hatton of Milwaukee, E. S. Rankin of Newark, New Jersey, and George C. D. Lenth of Chicago, Illinois. Representatives of the Cement Concrete Pipe Industry were also in attendance, among whom were representatives of the Sherman Concrete Pipe Company of Knoxville, Tennessee; F. C. Buente of the Concrete Products Company of Pittsburgh, Pennsylvania; Mr. Decker of the Lock Joint Pipe Company of Ampere, New Jersey; Mr. Robertson of the Independent Concrete Pipe Company of Indianapolis, Indiana, and Mr. Kimmel of the Hume Concrete Pipe Company of Detroit. Your Chairman announced that the subjects to be considered at the hearing were, viz.: 1st. The specifications for the testing of large-size sewers, which matter is now a tentative specification with the Society. 2nd. Certain suggestions by the Concrete Pipe interests as to changes in the specifications for sewers, which were adopted as standard at the meeting of the Society at Cleveland. Objections were raised with respect to the first topic, in that the specifications for the testing of large-size sewers did not include the testing of large reinforced concrete pipe. No constructive method was presented to the Committee on this subject whereupon the Committee considered the objections to the standard specifications for sewers as presented by the reinforced concrete pipe manufacturers. Discussion took place as to the methods of testing pipe by the three point, the two point, and the sand bearing method of A. S. T. M. The discussion brought out the impracticability of testing a large sewer by the two-point method, as well as the testing of these sewers by the three-point method. The point brought out was that a strip one inch in width for the upper and lower bearing for the two-point method was not sufficient bearing for the proper conducting of a test, and the three-point method with two strips one inch apart was in the same category. It was urged that the Committee consider the elimination of the two-point method and to consider a modification of the threepoint method, by amending the space between the two lower bearings so that the space would be more than one inch, but rather that it would be a function of the diameter of the sewer. It was further pointed out that a one-inch space is sufficient for a twelve-inch pipe and that for a twenty-four inch pipe the space should be two inches, for a thirty-six inch pipe three inches, and the space increasing so that the same would be equal to one-twelfth of the diameter of the pipe. The attention of the Committee was directed to the fact that this subject was under consideration by Committee C4 of A. S. T. M. In as much as the Society was represented by Mr. Rankin on Committee C4, your Committee deemed it advisable not to make any changes in the specifications until Committee C4 had acted. The next subject was a matter of a modification of the permissible variation in diameter, as well as the permissible variation in shell thickness, as set forth in paragraph 35 of the sewer specifications. The Reinforced Cement Concrete Pipe manufacturers offered the suggestion to the Committee that the variation permitted in diameter of three-quarters of one per cent was not practicable from the manufacturers' viewpoint, and recommended that this provision be modified so that the variation be one and one-half per cent of the diameter. The Committee compared this request with the permissible variations as set forth in the pipe specifications of A. S. T. M., and noted that they were in variance. The Committee also. compared the request that the shell thickness have a tolerance of five per cent and that in no case shall the minimum be less than one-quarter of an inch. The Committee was advised that Committee C4 of A. S. T. M. had this subject under consideration. Mr. Harrison P. Eddy of Boston being the Chairman of the sub-committee on Dimensions and Variations, and that this committee would doubtless report on this matter at an early date. It was, therefore, the sense of your Committee that action on this matter be deferred until a report was made by Committee C4 of A. S. T. M. One of the manufacturers of reinforced concrete pipe, lotated on the Pacific Coast, directed the Committee's attention to paragraph 44 of the sewer specifications, and pointed out that this paragraph did not permit the use of steel wire reinforcement as was manufactured in that locality and used by them. Your Committee recommends that paragraph 44 of the sewer specifications be amended to conform with the tentative specifications of cold drawn steel wire of A. S. T. M. Mr. C. F. Buente presented a paper to your Committee regarding the design of reinforced concrete pipe; he directed the Committee's attention to the methods used by him in computing the crushing strength of the commodity represented by him. The paper sets forth what appeared to be an error in paragraphs 41-42 of the sewer specifications. The contention of the reinforced concrete pipe interests being that there was a transposition in the columns setting forth the minimum crushing strength, and that the figures given in the sewer specifications exceeded the requirements of culvert pipe as used in railroad construction, and hence the industry represented by him was laboring under a disadvantage. The recommendation as to a definition of "First Crack" and "Ultimate Failure" should be incorporated in the specifications. Your chairman advised those present that your Committee. attempted an intensive canvass of the membership of the Society interested in the subjects discussed, but that your Committee had but few responses. That the objection to suggestions of the reinforced concrete pipe interests had been received by your chairman a week prior to this convention. It was the sense of your Committee that this was an important matter, and one that should be carefully considered by the Sewer Committee; that the time between receipt of the communication from the reinforced concrete people and the commencement of this convention was inadequate for the proper study and handling of this important matter. The Committee appreciates that the Iowa State College, under the direction of Anson Marston, had made a comprehensive study of the subject and that an effort would be made to get in touch with Dean Marston, and from him obtain data for the Committee. The representatives of the reinforced concrete pipe interests requested your Committee to recommend the withdrawal of the sewer specifications, which had been adopted by the Society, pending your Committee's consideration of the subjects herein discussed. It was the opinion of your Committee that inasmuch as these specifications had been in use for approximately three years and that no criticisms or amendments. had been suggested until within the last fifteen days, that the Committee was not justified in acceding to the manufacturers' request. Whereupon the reinforced concrete pipe interests requested of your chairman that they be notified of the time and place of the hearing, so that they could be present when this matter was under consideration. Your chairman, on behalf of the Sewer Committee, has promised to give them due notice of the time and place so that a hearing may be had on the subject. Your chairman herewith transmits to the Secretary of the Society a copy of this report, together with the entire file of correspondence on this matter. Respectfully submitted, FRANK R. ALLEN, Chairman. E. E. BUTTERFIELD. MR. ALLEN: I wish to state further that since the committee meeting on Tuesday we have had some further communications and find them diametrically opposite from the reports reived up to Tuesday, from the same manufacturers; so we believed that the entire matter should be carried over to the committee taking up the matter next year. I move that the paragraph with reference to 44 in regard to steel reinforcement be regularly submitted by ballot to the So ciety and that the rest of the report be referred to the incoming committee. A MEMBER: I second the motion. CHAIRMAN POOLE: It has been moved and seconded that the report with reference to Paragraph 44 be submitted to letter ballot and the rest be referred to the incoming committee. Is there any discussion? All those in favor signify by saying aye; opposed, no. The motion is carried. REPORT OF CANVASSING COMMITTEE OF VOTES CAST BY LETTER BALLOT Vote on the amendment to paragraph 44 of the present standard specifications for sewers: voting, 2. Yes, 102; noes, 2; not E. R. KINSEY, W. W. HORNER, C. L. HAWKINS. |