TENTATIVE RESULTS ON CAPACITY OF CURB OPENING INLETS, WITH DISCUSSION

A METHOD IS PRESENTED OF ESTIMATING THE CAPACITY OF A CURB OPENING INLET AS A FUNCTION OF THE DEPTH OF FLOW IN THE APPROACH GUTTER, THE DEPRESSION OF THE INLET LIP BELOW THE FLOW LINE OF THE GUTTER, AND THE LENGTH OF THE OPENING. THE METHOD NOT ONLY INDICATES THE FLOW WHICH WOULD BE ENTIRELY INTERCEPTED BY A GIVEN INLET BUT ALSO THE PERCENTAGE OF THE TOTAL FLOW IN THE GUTTER WHICH WOULD BE INTERCEPTED AS THE DISCHARGE IS INCREASED BEYOND THAT POINT. THIS METHOD IS BASED ON A THEORETICAL ANALYSIS WHICH TREATS THE CURB OPENING AS A WEIR WITH THE HEAD DECREASING ALONG THE CREST. DESPITE A NUMBER OF SIMPLIFYING ASSUMPTIONS IN THE ANALYSIS, EXPERIMENTAL DATA FROM THREE INDEPENDENT INVESTIGATIONS VERIFY, WITHIN PRACTICAL LIMITS, THE VALIDITY OF THE THEORY. THE STUDY SUBSTANTIATES THE BELIEF OF PRACTICAL ENGINEERS THAT DEPRESSION OF THE GUTTER FLOW LINE IS NECESSARY TO ACHIEVE REASONABLY EFFICIENT OPERATION WITH THE CURB OPENING TYPE OF INLET. IT ALSO PROVES THAT THE CAPACITY OF THE INLET VARIES WITH THE GRADE AND ALSO WITH THE CROSS SECTION OF THE STREET AS IT AFFECTS THE DEPTH OF FLOW. THE SECOND PART OF THE PAPER INCLUDES SUGGESTIONS AS TO HOW THE ENGINEER MIGHT APPLY THE RESULTS OF THIS STUDY TO THE DESIGN OF CURB OPENING INLETS, ESPECIALLY FOR EXPRESS HIGHWAYS. A BRIEF DISCUSSION IS INCLUDED OF THE RELATIVE CAPACITIES OF CURB OPENING AND GRATE INLETS. /AUTHOR/

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  • Corporate Authors:

    Highway Research Board (HRB)

    Washington, DC   
  • Authors:
    • Izzard, Carl F
  • Discussers:
    • Jens, Stifel W
  • Conference:
  • Publication Date: 1950-12

Media Info

  • Media Type: Digital/other
  • Features: Figures; References; Tables;
  • Pagination: 19p
  • Monograph Title: Surface drainage
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00204410
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: May 22 1972 12:00AM