en Water-Hydraulic Structure Water-Hydraulic Structure Research Paper Research Paper <p class="1" style="MARGIN: 0cm 0cm 0pt DIRECTION: ltr TEXT-INDENT: 0cm LINE-HEIGHT: 150% unicode-bidi: embed TEXT-ALIGN: justify mso-margin-top-alt: auto mso-margin-bottom-alt: auto"><span style="FONT-SIZE: 10pt LINE-HEIGHT: 150%"><strong><font face="Times New Roman">ABSTRACT<p></p></font></strong></span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt DIRECTION: ltr LINE-HEIGHT: 150% unicode-bidi: embed TEXT-ALIGN: left mso-margin-top-alt: auto mso-margin-bottom-alt: auto"><font face="Times New Roman"><span style="FONT-SIZE: 10pt LINE-HEIGHT: 150%">Induced total pressure by flow, including mean and fluctuating components, around a selected chute block in SAF stilling basins downstream of an ogee spillway was studied. Several pressure holes were selected on various faces of a selected chute block to get enough information regarding the total pressure field. </span><span style="FONT-SIZE: 10pt LINE-HEIGHT: 150% mso-bidi-font-family: Lotus">This paper reports the results of an experimental work and measurement of mean and </span><span style="FONT-SIZE: 10pt LINE-HEIGHT: 150%">fluctuation pressures around chute block</span><span style="FONT-SIZE: 10pt LINE-HEIGHT: 150% mso-bidi-font-family: Lotus">s of SAF stilling basins. </span><span lang="EN-US" style="FONT-SIZE: 10pt LINE-HEIGHT: 150% mso-ansi-language: EN-US">The observations showed that the maximum total pressure varies inversely with Froude number of incoming flow while its position of occurrence follows </span><span style="FONT-SIZE: 10pt LINE-HEIGHT: 150%">a quadratic polynomial relation ship.</span><span lang="EN-US" style="FONT-SIZE: 10pt LINE-HEIGHT: 150% mso-bidi-font-family: Lotus mso-ansi-language: EN-US"> Statistical analysis also showed that the peak instantaneous pressure fluctuations could be as large as ±4.5times the <i>RMS</i> value.</span><span style="FONT-SIZE: 10pt LINE-HEIGHT: 150% mso-bidi-font-family: Lotus">It is concluded that </span><span style="FONT-SIZE: 10pt LINE-HEIGHT: 150%">pressure fluctuation</span><span style="FONT-SIZE: 10pt LINE-HEIGHT: 150% mso-bidi-font-family: Lotus"> around the chute blocks may double the magnitude of pressure field around the chute blocks and can not be overlooked in designing such<b> </b>appurtenances.</span></font><span style="mso-bidi-font-family: Yagut"><p></p></span></p> Keywords: SAF stilling basin, chute blocks, pressure field, pressure fluctuation, submergence ratio 271 279 http://ijce.iust.ac.ir/browse.php?a_code=A-10-135-1&slc_lang=en&sid=1 Javad Farhoudi jfarhoudi@ut.ac.ir 180031947532846001331 180031947532846001331 Yes The University of Tehran