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<h2>6.7 Traffic Railing [13.7]</h2>

<h3><a name=6.4.1>6.7.1 General</a></h3>

<p class=OutlineA>A. Unless otherwise approved, all new bridge, approach 
 slab and retaining wall mounted traffic railings, traffic railing/sound 
 barrier combinations and traffic railing/glare screen combinations proposed 
 for use in new or temporary construction, resurfacing, restoration, rehabilitation 
 (RRR) and widening projects must:</p>

<p class=OutlineA1>1.) Have been successfully crash tested to Test Level 
 4 (minimum), Test Level 5 or Test Level 6 criteria (as appropriate) in 
 accordance with <span style="font-weight: bold; font-style: italic;"><I><B>National 
 Cooperative Highway Research Program (NCHRP) Report 350</B></I></span> and <span 
 style="font-weight: bold; font-style: italic;"><I><B>LRFD</B></I></span> for permanent 
 installations.</p>

<p class=OutlineA1>2.) Have been successfully crash tested to Test Level 
 3 (minimum) in accordance with <span style="font-style: italic; font-weight: bold;"><I><B>NCHRP 
 Report 350</B></I></span> and <span style="font-style: italic; font-weight: bold;"><I><B>LRFD</B></I></span> 
 for temporary installations shielding drop-offs.</p>

<p class=OutlineA1>3.) Have been successfully crash tested to Test Level 
 2 (minimum) in accordance with <span style="font-style: italic; font-weight: bold;"><I><B>NCHRP 
 Report 350</B></I></span> and <span style="font-style: italic; font-weight: bold;"><I><B>LRFD</B></I></span> 
 for temporary installations shielding work zones without drop-offs (45 
 mph or less design speed).</p>

<p class=OutlineA1>4.) Meet the appropriate strength and geometric requirements 
 of <span style="font-style: italic; font-weight: bold;"><I><B>LRFD</B></I></span> Section 
 13 for the given test levels and crash test criteria.</p>

<p class=OutlineA1>5.) Be upgraded on both sides of a structure when widening 
 work is proposed for only one side and the existing traffic railing on 
 the non-widened side does not meet the criteria for new traffic railings.</p>

<p class=OutlineA1>6.) Be constructed on decks reinforced in accordance 
 with Chapter 4 for permanent installations on new construction, widenings 
 and partial deck replacements.</p>

<p class=OutlineA1>7.) Be constructed on decks and walls meeting the requirements 
 of Section 6.7.4 for retrofit construction.</p>

<p class=OutlineA1>8.) Be constructed and installed in accordance with 
 the crash tested and accepted details for temporary installations.</p>

<p class=OutlineA>B. The traffic railings shown on the <span style="font-style: italic; font-weight: bold;"><I><B>Structures 
 Standard Drawings</B></I></span>, Index No. 700 Series and <span style="font-style: italic; font-weight: bold;"><I><B>Design 
 Standards</B></I></span> Index Nos. 412 and 413 have been determined to meet the 
 applicable crash testing requirements and should be used on structures 
 in Florida. The applicability of each of these standard traffic railings 
 in permanent installations is addressed in the <span style="font-style: italic; font-weight: bold;"><I><B>Plans 
 Preparation Manual, Volume I.</B></I></span></p>

<h3><a name=6_7_2></a><a name=6.4.2>6.7.2 Non-Standard or New Railing Designs</a> 
 <A href="javascript:void(0);" onclick="BSSCPopup('SDG_6.7_Traffic_Railing_text0.htm');return false;" onMouseOver="if (parseInt(navigator.appVersion) >= 4) BSPSPopupOnMouseOver(event);" class="popupspot" >(01/06)</a></h3>

<p class=OutlineA>A. The use of a non-FDOT standard or new structure mounted 
 traffic railing requires the prior approval of the Structures Design Office. 
 &nbsp;Proposed 
 modifications to standard traffic railings also require prior Structures 
 Design Office approval. &nbsp;Such 
 proposed modifications may include but are not limited to reinforcement 
 details, surface treatments, material substitutions, geometric discontinuities, 
 non-standardized attachments, end transition details and traffic face 
 geometry. &nbsp;</p>

<p class=OutlineA>B. Submit all proposed non-FDOT standard, new or modified 
 structure mounted traffic railing designs to the Structures Design Office 
 for review and possible approval. Make this submittal early in the design 
 process preferably prior to submittal of the Typical Section Package.</p>

<p class=OutlineA>C. A non-FDOT standard or new structure mounted traffic 
 railing design may be approved by the Structures Design Office if it meets 
 the requirements of No. 1 and Nos. 2, 3 or 4 below:</p>

<p class=OutlineA1>1.) The Structures Design Office has determined that 
 the design will provide durability, constructability, and maintainability 
 equivalent to the standard FDOT traffic railing designs.</p>

<p class=OutlineA1>2.) It has been successfully crash tested in accordance 
 with NCHRP Report 350 Test Level 4 (minimum) criteria for permanent installations 
 and Test Level 2 or 3 criteria (as appropriate) for temporary installations.</p>

<p class=OutlineA1>3.) It has been approved for specific uses by FHWA after 
 evaluation of results from successful crash testing based on criteria 
 that predate NCHRP Report 350 Test Levels 2, 3 and 4 (as appropriate).</p>

<p class=OutlineA1>4.) It has been evaluated by the Structures Design Office 
 and identified as similar in strength and geometry to another traffic 
 railing that has been successfully crash tested in accordance with NCHRP 
 Report 350 Test Level 4 (minimum) criteria for permanent installations 
 and Test Level 2 or 3 criteria (as appropriate) for temporary installations.</p>

<p class=OutlineA
	style="font-style: italic;">Commentary:</p>

<p class="whs9">The background for this policy is based 
 on the Test Level Selection Criteria as defined in Section 13 of the AASHTO 
 LRFD Bridge Design Specifications and on historical construction costs 
 and in-service performance of standard FDOT Test Level 4 traffic railings 
 used in permanent installations. &nbsp;This 
 background can be summarized as follows:</p>

<p class=OutlineA
	style="font-style: italic;">1. In general, a greater potential exists 
 for overtopping or penetrating a shorter height, lower test level traffic 
 railing versus a similarly shaped Test Level 4 traffic railing. &nbsp;This 
 potential is further aggravated on tall bridges and on bridges over intersecting 
 roadways or water deep enough to submerge an errant vehicle. &nbsp;Vehicle 
 performance during higher speed impacts is also more critical on lower 
 test level traffic railings.</p>

<p class=OutlineA
	style="font-style: italic;">2. Little construction cost savings can 
 be realized by using a lower test level traffic railing. &nbsp;In 
 some cases, particularly with the more elaborate or ornate traffic railing 
 designs, initial construction costs and long term repair and maintenance 
 costs could actually be greater than those for a standard FDOT Test Level 
 4 design.</p>

<p class=OutlineA
	style="font-style: italic;">3. Aesthetically pleasing and open Test 
 Level 4 designs are available for use where appropriate.</p>

<p class=OutlineA
	style="font-style: italic;">4. On bridges and retaining walls with 
 sidewalks where special aesthetic treatments are desired or required, 
 the use of an aesthetic pedestrian railing located behind a Test Level 
 4 traffic railing is a more appropriate solution. &nbsp;The 
 aesthetics of the traffic railing should complement the pedestrian railing.</p>

<p class=OutlineA>D. For more detailed information on FDOT structure mounted 
 traffic railings, refer to the <span style="font-style: italic; font-weight: bold;"><I><B>Structures 
 Standard Drawings</B></I></span>. &nbsp;For 
 additional information about crash-tested traffic railings currently available 
 or about traffic railings currently under design or evaluation, contact 
 the Structures Design Office.</p>

<p class=OutlineA
	style="text-indent: 0px;
			margin-left: 0px;
			font-style: normal;">E. Use the traffic railing surface texture 
 guidelines given below for &nbsp;the 
 selection of proposed texturing of the traffic face of 32-inch and 42-inch 
 Vertical Face Traffic Railings and the upper vertical portion of the Traffic 
 Railing/Sound Barrier combination. Maintain <a href="SDG_1.4_Concrete_and_Environment.htm#Concrete_Cover">SDG 
 1.4 concrete cover requirements</a> at the point of deepest relief. Modify 
 standard concrete products to maintain the proper cover but do not modify 
 the geometry of the traffic face of the railing.</p>

<p class=OutlineA1>1.) Sandblasted textures covering the majority of the 
 railing surface with a maximum relief of 3/8-inches.</p>

<p class=OutlineA1>2.) Images or geometric patterns inset into the face 
 of the railing 1-inch or less and having 45-degree or flatter chamfered 
 or beveled edges to minimize vehicular sheet metal or wheel snagging.</p>

<p class=OutlineA1>3.) Textures or patterns of any shape and length inset 
 into the face of the railing up to 1/2-inch deep and 1-inch wide and having 
 60-degree or flatter chamfered or beveled edges to facilitate form removal.</p>

<p class=OutlineA1>4.) Any texture or pattern with gradual undulations 
 (e.g. cobblestone) that has a maximum relief of 3/4-inch over a distance 
 of one foot.</p>

<p class=OutlineA>F. Patterns or textures must be cast into or otherwise 
 integral with the traffic face or top of traffic railings. Do not specify 
 textures, patterns or features, e.g. brick, stone, or tile veneers, etc. 
 on the traffic face or top of traffic railings that have to be attached 
 a separate element. Such features may be considered for attachment to 
 the back face of traffic railings and pedestrian railings on a project 
 by project basis in locations not over or directly beside other travelways.</p>

<p class=OutlineA><span style="font-style: italic;"><I>Commentary:</I></span></p>

<p class=OutlineA
	style="text-indent: 0px;
			margin-left: 0px;
			font-style: italic;">The above guidelines for concrete railing 
 texturing will not adversely affect the NCHRP Report 350 test level of 
 the railing to which a texture or pattern is applied. However, it is clear 
 from crash test results that textured railings can result in more vehicular 
 body damage in a crash due to increased friction even if crash performance 
 remains within acceptable limits.</p>

<p class=OutlineA
	style="text-indent: 0px;
			margin-left: 0px;
			font-style: italic;">Aesthetic attachments to the back of the 
 traffic railing may become dislodged when the railing is impacted and 
 create a hazard to roadways located under or beside the structure. For 
 this reason, aesthetic attachments shall not be used on the back of railings 
 located over or directly beside other travelways. Railings with aesthetic 
 features generally cannot be slip formed resulting in increased construction 
 time and cost.</p>

<p class=OutlineA
	style="text-indent: 0px;
			margin-left: 0px;
			font-style: italic;">The selection of a proposed railing texture 
 or pattern should take into account the overall aesthetic concept of the 
 structure, maintainability of the feature and the long service of the 
 structure. Shapes of traffic railings create the major aesthetic impression, 
 colors, textures, and patterns are secondary. Form liners that try to 
 imitate small scale detail are wasted at highway speeds but may be appropriate 
 for areas with pedestrian traffic.</p>

<h3><a name=6.4.3>6.7.3 FHWA Policy</a></h3>

<p class=OutlineA>A. Since September 1, 1986, the Federal Highway Administration 
 (FHWA) has required highway bridges on the National Highway System (NHS) 
 and the Interstate Highway System to have crash-tested railing. Current 
 policy is stated in the following documents:</p>

<p class=OutlineA1>1.) Intermodal Surface Transportation Efficiency Act 
 of 1991 (ISTEA).</p>

<p class="whs10">http://<a href="http://www.fhwa.dot.gov/legsregs/legislat.html"
										target=_blank>www.fhwa.gov/legsregs/legislat.html</a></p>

<p class="whs11">Required that measures 
 to enhance the crashworthiness of roadside features accommodate vans, 
 minivans, pickup trucks, and 4-wheel drive vehicles, as well as cars.</p>

<p class=OutlineA1>2.) National Cooperative Highway Research Program (NCHRP) 
 Report 350, Recommended Procedures for the Safety Performance Evaluation 
 of Highway Features.</p>

<p class="whs12">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;http://<a 
 href="http://safety.fhwa.dot.gov/programs/roadside_hardware.htm"
	target=_blank>safety.fhwa.dot.gov/programs/roadside_hardware.htm</a></p>

<p class="whs11">Provides guidance for 
 testing highway features to assess safety performance of those features. 
 Guidance includes definitions of crash-test levels with specified vehicle, 
 speed, and impact angle for each level.</p>

<p class=OutlineA1>3.) May 30, 1997, memorandum from Dwight Horne on the 
 subject of &quot;Crash Testing of Bridge Railings.&quot;</p>

<p class="whs13">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;http://<a 
 href="http://safety.fhwa.dot.gov/fourthlevel/hardware/pdf/bridge.pdf"
	target=_blank>safety.fhwa.dot.gov/fourthlevel/hardware/pdf/bridge.pdf</a></p>

<p class="whs11">Identifies 68 crash-tested 
 bridge rails, consolidating earlier listings and establishing tentative 
 equivalency ratings that relate previous testing to <span style="font-weight: bold;"><B>NCHRP 
 Report 350</B></span> test levels.</p>

<p class=OutlineA1>4.) July 25, 1997 memorandum from Donald Steinke on 
 the subject of &quot;Identifying Acceptable Highway Safety Features.&quot;</p>

<p class="whs13">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;http://<a 
 href="http://www.fhwa.dot.gov/legsregs/directives/policy/ra.htm"
	target=_blank>fhwa.dot.gov/legsregs/directives/policy/ra.htm</a></p>

<p class="whs11">Clarifies and summarizes 
 policies on bridge traffic railing, points to authorities for requiring 
 testing of bridge traffic railing, and identifies methods for submitting 
 new rails for testing. &nbsp;This 
 document also identifies exceptions, one of which is the replacement or 
 retrofitting of existing bridge traffic railing unless improvements are 
 being made on a stretch of highway that includes a bridge with obsolete 
 railing.</p>

<p class=OutlineA>B. On its web site, FHWA provides current information 
 on three general categories of roadside hardware that are tested and evaluated 
 using <span style="font-style: italic; font-weight: bold;"><I><B>NCHRP Report 
 350</B></I></span> criteria; one of those categories is Bridge Railing.</p>

<p class="whs14">See Bridge Railings at http://<span style="margin-left: 19px; text-indent: -19px;"><a 
 href="http://safety.fhwa.dot.gov/fourthlevel/hardware/bridgerailings.htm"
	target=_blank>safety.fhwa.dot.gov/fourthlevel/hardware/bridgerailings.htm</a></span></p>

<h3><a name=6></a><a name=6_7_4>6.7.4 Existing Obsolete Traffic Railings 
 <A href="javascript:void(0);" onclick="BSSCPopup('SDG_6.7_Traffic_Railing_text1.htm');return false;" onMouseOver="if (parseInt(navigator.appVersion) >= 4) BSPSPopupOnMouseOver(event);" class="popupspot" >(01/06)</a></a></h3>

<p class=OutlineA>A. General</p>

<p class=OutlineA1>1.) FDOT promotes highway planning that replaces or 
 upgrades non-crash tested traffic railing on existing bridges to current 
 standards, or that at least increases the strength or expected crash performance 
 of these traffic railings. &nbsp;FDOT 
 has developed two sets of Structures Standards, the Index 770 and 780 
 Series, for retrofitting existing structures with traffic railing types 
 that have performed well in crash tests and are reasonably economic to 
 install. &nbsp;Detailed 
 instructions and procedures for retrofitting obsolete traffic railings 
 on existing structures are included in the Structures Standard Drawings.</p>

<p class=OutlineA1>2.) For RRR projects, existing bridge traffic railing 
 retrofits constructed in accordance with 1987 through 2000 Roadway and 
 Traffic Design Standards, Index 401, Schemes 1 and 19 “Concrete Safety 
 Barrier” and Scheme 16 “Guardrail Continuous Across Bridge” and their 
 accompanying approach and trailing end guardrail treatments may be left 
 in place provided they meet the criteria set forth in the Plans Preparation 
 Manual, Volume I, Sections 25.4.25.3 and 25.4.26.2.</p>

<p class=OutlineA1>3.) When rehabilitation or renovation work is proposed 
 on an existing structure with traffic railings that do not meet the criteria 
 for new or existing railings as provided above, replace or retrofit the 
 existing traffic railings to meet the crash-worthy criteria unless an 
 exception is approved. &nbsp;Refer 
 to Chapter 23 of the Plans Preparation Manual, Volume 1, for information 
 about exceptions.</p>

<p class=OutlineA1>&nbsp;</p>

<p class="whs9">Commentary: The obsolete standard entitled 
 “Guardrail Anchorage and Continuous Barrier for Existing Bridges”, Index 
 No. 401, was included in the Roadway and Traffic Design Standards from 
 1987 until 2000. &nbsp;Schemes 
 1 and 19 of this standard entitled “Concrete Safety Barrier” are based 
 on a design that has been crash tested as documented in Transportation 
 Research Report TRP-03-19-90 and accepted by FHWA at NCHRP Report 350 
 Test Level 4. &nbsp;Scheme 
 16 of this standard entitled “Guardrail Continuous Across Bridge” has 
 been structurally evaluated and has been determined to be acceptable to 
 FDOT and FHWA to leave in place on RRR projects provided the installation 
 meets the criteria given herein. &nbsp;</p>

<p class="whs9">Specify in the Plans the necessary upgrades 
 to the existing guardrail transitions as follows.</p>

<p><span style="font-style: italic;"><I>For the w-beam approach transition 
 shown as Detail J in the 1987 edition of the Roadway and Traffic Design 
 Standards, Index 400 without a continuation of curb beyond the bridge</I></span> 
 <span style="font-style: italic;"><I>or approach slab, use the following 
 Plan Sheet note placed adjacent to bridge ends: </I></span></p>

<p class="whs9">Construct Transition Block, nested W Beam 
 Guardrail and additional Guardrail Posts and Offset Blocks as shown in 
 Interim Design Standards Index 403.</p>

<p class="whs9">For the w-beam approach transition shown 
 as Detail J in the 1987 edition of the Roadway and Traffic Design Standards, 
 Index 400 with a continuation of curb beyond the bridge or approach slab, 
 use the following Plan Sheet note placed adjacent to bridge ends: </p>

<p class="whs9">Construct nested W Beam Guardrail and additional 
 Guardrail Posts and Offset Blocks as shown in Interim Design Standards 
 Index 403.</p>

<p class="whs9">For the nested w-beam approach transition 
 shown as Detail J in the 1998 edition of the Roadway and Traffic Design 
 Standards, Index 400 without a continuation of curb beyond the bridge 
 or approach slab, use the following Plan Sheet note placed adjacent to 
 bridge ends: </p>

<p class="whs9">Construct Transition Block as shown in Interim 
 Design Standards Index 403.</p>

<p class="whs9">For all trailing end treatments, specify 
 the necessary guardrail upgrades as appropriate.</p>

<p class="whs9">&nbsp;</p>

<p class=OutlineA>B. FHWA Policy on Existing Traffic Railings</p>

<p class=Normal3>The FHWA requires that bridge railing on the National 
 Highway System (NHS) meet requirements of <span style="font-weight: bold; font-style: italic;"><I><B>NCHRP 
 Report 350:</B></I></span></p>

<p class=Normal3>&quot;all new or replacement safety features on the NHS 
 covered by the guidelines in the <span style="font-style: italic; font-weight: bold;"><I><B>NCHRP 
 Report 350</B></I></span> that are included in projects advertised for bids or 
 are included in work done by force-account or by State forces on or after 
 October 1, 1998, are to have been tested and evaluated and found acceptable 
 in accordance with the guidelines in the <span style="font-weight: bold; font-style: italic;"><I><B>NCHRP 
 Report 350</B></I></span> &quot; (See Section 6.7.3, Number 4).</p>

<p class=Normal3>&nbsp;</p>

<p class=Normal3>However, FHWA softens this requirement somewhat by allowing 
 exceptions:</p>

<p class=Normal3>&quot;Bridge railings tested and found acceptable under 
 other guidelines may be acceptable for use on the NHS.&quot; This is a 
 specific reference to the Horne memo titled &quot;Crash Testing of Bridge 
 Railings&quot; (See Section 6.7.3, Number 3.)</p>

<p class=Normal3>&nbsp;</p>

<p class=Normal3>&quot;The FHWA does not intend that this requirement (that 
 new safety features installed on the NHS be proven crashworthy in accordance 
 with the guidelines in the <span style="font-weight: bold; font-style: italic;"><I><B>NCHRP 
 Report 350</B></I></span>) result in the replacement or upgrading of any existing 
 installed features beyond what would normally occur with planned highway 
 improvements.&quot;</p>

<p class=Normal3>&nbsp;</p>

<p class=Normal3>This statement is qualified by a requirement that states 
 have a &quot;rational, documented policy for determining when an existing 
 non-standard feature should be upgraded.&quot;</p>

<p class=OutlineA>C. Traffic Railing Retrofit Concepts and Standards </p>

<p>Existing non-crash tested traffic railings designed in accordance with 
 past editions of the AASHO and AASHTO Standard Specifications for Highway 
 Bridges will likely not meet current crash test requirements and will 
 also likely not meet the strength and height requirements of the AASHTO 
 LRFD Bridge Design Specifications. &nbsp;The 
 retrofitting of these existing non-crash tested traffic railings reduces 
 the separate but related potentials for vehicle snagging, vaulting and/or 
 penetration that can be associated with many obsolete, non-crash tested 
 designs.</p>

<p>&nbsp;</p>

<p>The Thrie Beam Guardrail Retrofit and Vertical Face Retrofit Structures 
 Standards, Index 770 and 780 Series, respectively, are suitable for retrofitting 
 specific types of obsolete structure mounted traffic railings. &nbsp;These 
 retrofits provide a more economical solution for upgrading obsolete traffic 
 railings when compared with replacing the obsolete traffic railings and 
 portions of the existing bridge decks or walls that support them. &nbsp;As 
 these retrofits do not provide for any increase in clear width of roadway, 
 and in a few cases decrease clear width by approximately 2 inches, they 
 should only be considered for use on structures where adequate lane and 
 shoulder widths, sight distances and transition lengths are present. &nbsp;The 
 potential effects of installing a retrofit should be evaluated to ensure 
 that the accident rate will not increase as a result. &nbsp;Detailed 
 guidance and instructions on the design, plans preparation requirements 
 and use of these retrofits is included in the individual Structures Standards.</p>

<p>&nbsp;</p>

<p>When selecting a retrofit or replacement traffic railing for a structure 
 that will be widened or rehabilitated, or for a structure that is located 
 within the limits of a RRR project, evaluate the following aspects of 
 the project:</p>

<p class=OutlineA1>1.) Elements of the structure </p>

<p class=OutlineA1a>a.) Width, alignment and grade of roadway along structure.</p>

<p class=OutlineA1a>b.) Type, aesthetics, and strength of existing railing.</p>

<p class=OutlineA1a>c.) Structure length.</p>

<p class=OutlineA1a>d.) Potential for posting speed limits in the vicinity 
 of the structure.</p>

<p class=OutlineA1a>e.) Potential for establishing no-passing zones in 
 the vicinity of the structure.</p>

<p class=OutlineA1a>f.) Approach and trailing end treatments (guardrail, 
 crash cushion or rigid shoulder barrier).</p>

<p class=OutlineA1a>g.) Strength of supporting bridge deck or wall.</p>

<p class=OutlineA1a>h.) Load rating of existing bridge.</p>

<p class=OutlineA1>2.) Characteristics of the structure location</p>

<p class=OutlineA1a>a.) Position of adjacent streets and their average 
 daily traffic.</p>

<p class=OutlineA1a>b.) Structure height above lower terrain or waterway.</p>

<p class=OutlineA1a>c.) Approach roadways width, alignment and grade.</p>

<p class=OutlineA1a>d.) Design speed, posted speed, average daily traffic 
 and percentage of truck traffic.</p>

<p class=OutlineA1a>e.) Accident history on the structure.</p>

<p class=OutlineA1a>f.) Traffic control required for initial construction 
 of retrofit and for potential future repairs.</p>

<p class=OutlineA1a>g.) Locations and characteristics of pedestrian facilities 
 / features (if present).</p>

<p class=OutlineA1>3.) Features of the retrofit designs</p>

<p class=OutlineA1a>a.) Placement or spacing of anchor bolts or dowels.</p>

<p class=OutlineA1a>b.) Reinforcement anchorage and potential conflicts 
 with existing reinforcement, voids, conduits, etc.</p>

<p class=OutlineA1a>c.) Self weight of retrofit railing.</p>

<p class=OutlineA1a>d.) End treatments.</p>

<p class=OutlineA1a>e.) Effects on pedestrian facilities.</p>

<p class=OutlineA>D. Evaluation of Existing Supporting Structure Strength 
 for Traffic Railing Retrofits.</p>

<p>The Thrie Beam Guardrail and Vertical Face traffic railing retrofits 
 are based on designs that have been successfully crash tested in accordance 
 with <span style="font-weight: bold; font-style: italic;"><I><B>NCHRP Report 
 350</B></I></span> to Test Level 4 or have been previously tested and then accepted 
 at Test Level 4. The original designs have been modified for use with 
 some of the wide variety of traffic railings and supporting deck and wing 
 wall configurations that were historically constructed on Florida bridges. 
 &nbsp;In recognition 
 of the fact that the traffic railings and supporting elements were designed 
 to meet the less demanding requirements of past AASHO and AASHTO Bridge 
 Codes, modifications have been made to the original retrofit designs in 
 order to provide for better distribution of vehicle impact force through 
 the traffic railing retrofit and into the supporting bridge deck or wing 
 wall. &nbsp;For 
 Thrie Beam Guardrail Retrofit installations on narrow curbs and or lightly 
 reinforced decks or walls, a smaller post spacing is used on bridge decks. 
 &nbsp;In addition, 
 through-bolted anchors are used for some Thrie Beam Guardrail Retrofit 
 installations. For the Vertical Face Retrofit, additional longitudinal 
 reinforcing steel and dowel bars at the open joints are used within the 
 new railing.</p>

<p>&nbsp;</p>

<p>Existing bridge decks and walls that will support a traffic railing 
 retrofit must be evaluated to determine if sufficient strength is available 
 to ensure that the retrofit will perform in a manner equivalent to that 
 demonstrated by crash testing. &nbsp;Existing 
 structures may contain Grade 33 reinforcing steel if constructed prior 
 to 1952 or Grade 40 reinforcing steel if constructed prior to 1972. Use 
 90% of the ultimate tensile strength of these materials when determining 
 the existing capacity for both tension and moment from traffic railing 
 impacts (<span style="font-size: 12pt;"><font size=3 style="font-size:12pt;">f</font></span><span style="vertical-align: Sub;">s</span> 
 = 49.5 ksi for Grade 33, <span style="font-size: 12pt;"><font size=3 style="font-size:12pt;">f</font></span><span 
 style="vertical-align: Sub;">s</span><span style="font-size: 12pt;"> <font size=3 style="font-size:12pt;"></font></span>= 
 60 ksi for Grade 40). &nbsp;For 
 existing structures containing Grade 60 reinforcing steel, only use the 
 yield strength of this material (<span style="font-size: 12pt;"><font size=3 style="font-size:12pt;">f</font></span><span 
 style="vertical-align: Sub;">s</span> = 60 ksi). For bridges with varying 
 spacings and sizes of transverse reinforcing steel in the deck or curb, 
 the average area of transverse steel for the span may be used.</p>

<p>&nbsp;</p>

<p>Existing cast-in-place reinforced concrete bridge decks shall be analyzed 
 at a section through the deck at the gutter line for the appropriate FDOT 
 traffic railing retrofit Standard Indexes using the following design values:</p>

<p>&nbsp;</p>

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<col class="whs16">
<col class="whs16">
<col class="whs16">

<tr valign="top" class="whs4">
<td valign="middle" width="25%" class="whs17">
<p align="center" class="whs18">Traffic Railing Type</td>
<td valign="middle" width="25%" class="whs19">
<p align="center" class="whs18">Standard Index No.</td>
<td valign="middle" width="25%" class="whs19">
<p align="center" class="whs20">M<span style="vertical-align: Sub;">g</span></td>
<td valign="middle" width="25%" class="whs19">
<p align="center" class="whs20">T<span style="vertical-align: Sub;">u</span></td></tr>

<tr valign="top" class="whs4">
<td valign="middle" width="25%" class="whs21">
<p align="center" class="whs22">Thrie-Beam Retrofit</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">772, 776 &amp; 777</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">5.8</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">4.7</td></tr>

<tr valign="top" class="whs4">
<td valign="middle" width="25%" class="whs21">
<p align="center" class="whs22">Thrie-Beam Retrofit</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">773 &amp; 775</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">8.3</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">6.7</td></tr>

<tr valign="top" class="whs4">
<td valign="middle" width="25%" class="whs21">
<p align="center" class="whs22">Thrie-Beam Retrofit</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">774</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">9.7</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">7.9</td></tr>

<tr valign="top" class="whs4">
<td valign="middle" width="25%" class="whs21">
<p align="center" class="whs22">Vertical-Face Retrofit</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">782-785</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">12.9</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">7.5</td></tr>
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<p>&nbsp;</p>

<p><span style="font-family: Arial, sans-serif; font-weight: bold;"><B>M</B></span><span 
 style="vertical-align: Sub;
		font-family: Arial, sans-serif;
		font-weight: bold;"><B>g</B></span> (kip-ft/ft) - Ultimate deck moment 
 at the gutter line from the traffic railing impact.</p>

<p>&nbsp;</p>

<p><span style="font-family: Arial, sans-serif; font-weight: bold;"><B>T</B></span><span 
 style="vertical-align: Sub;
		font-family: Arial, sans-serif;
		font-weight: bold;"><B>u</B></span><span style="font-size: 12pt; font-weight: bold;"> 
 <font size=3 style="font-size:12pt;"><B></B></font></span>(kip/ft) &nbsp;&nbsp;&nbsp;&nbsp;- 
 Total ultimate tensile force to be resisted.</p>

<p>The following relationship must be satisfied at the gutter line:</p>

<p>&nbsp;</p>

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<col class="whs3">
<col class="whs3">

<tr valign="top" class="whs4">
<td valign="middle" width="50%" class="whs24">
<p><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>(T</B></font></span><span style="font-weight: bold;
	font-size: 11pt;
	vertical-align: Sub;"><font size=3 style="font-size:11pt;"><B>u</B></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B> 
 / </B></font></span><span style="font-style: italic;
						font-weight: bold;
						font-size: 11pt;"><font size=3 style="font-size:11pt;"><I><B>&#934;</B></I></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>P</B></font></span><span 
 style="vertical-align: Sub;
		font-weight: bold;
		font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>n</B></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B> 
 )+ (M</B></font></span><span style="vertical-align: Sub;
							font-weight: bold;
							font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>u</B></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B> 
 / </B></font></span><span style="font-style: italic;
						font-weight: bold;
						font-size: 11pt;"><font size=3 style="font-size:11pt;"><I><B>&#934;</B></I></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>M</B></font></span><span 
 style="vertical-align: Sub;
		font-weight: bold;
		font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>n</B></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>) 
 &#8804; 1.0</B></font></span> </td>
<td valign="middle" width="50%" class="whs25">
<p align="right" class="whs26">(Eq. 6-1)</td></tr>
</table>

<p>&nbsp;</p>

<p class="whs27"><span style="font-size: 10pt;"><font size=2 style="font-size:10pt;">Where:</font></span> 
 </p>

<p>&nbsp;</p>

<p class="whs28">Ø = 1.0</p>

<p>&nbsp;</p>

<p><span style="font-weight: bold;"><B>P</B></span><span style="font-weight: bold; vertical-align: Sub;"><B>n</B></span><span 
 style="font-weight: bold;"><B> = &nbsp;A</B></span><span 
 style="vertical-align: Sub; font-weight: bold;"><B>s</B></span><span style="font-weight: bold;"><B>f</B></span><span 
 style="vertical-align: Sub; font-weight: bold;"><B>s</B></span><span style="vertical-align: Sub;
	font-size: 12pt;
	font-weight: bold;"> <font size=3 style="font-size:12pt;"><B></B></font></span>(kips/ft) - Nominal tensile capacity based 
 on the areas of transverse reinforcing steel in both the top and bottom 
 layers of the deck (<span style="font-weight: bold;"><B>A</B></span><span style="vertical-align: Sub; font-weight: bold;"><B>s</B></span>) 
 and the nominal reinforcing steel strength (<span style="font-weight: bold;"><B>f</B></span><span 
 style="vertical-align: Sub; font-weight: bold;"><B>s</B></span>). &nbsp;This 
 reinforcing steel must be fully developed at the critical section through 
 the deck at the gutter line.</p>

<p>&nbsp;</p>

<p><span style="font-weight: bold;"><B>M</B></span><span style="vertical-align: Sub; font-weight: bold;"><B>u</B></span> 
 = Total ultimate deck moment from traffic railing impact and factored 
 dead load at the gutter line. (<span style="font-weight: bold;"><B>M</B></span><span 
 style="vertical-align: Sub; font-weight: bold;"><B>g</B></span><span style="font-weight: bold;"><B>+1.25*M</B></span><span 
 style="vertical-align: Sub; font-weight: bold;"><B>Dead Load</B></span><span 
 style="font-weight: bold;"><B>) </B></span>(kip/ft/ft)<span style="font-weight: bold;"><B>.</B></span></p>

<p class="whs29">&nbsp;</p>

<p><span style="font-weight: bold;"><B>M</B></span><span style="vertical-align: Sub; font-weight: bold;"><B>n 
 </B></span>&nbsp;= 
 Nominal moment capacity at the gutter line determined by traditional rational 
 methods for reinforced concrete (kip-ft/ft). The bottom layer of steel 
 must not be included unless a strain compatibility analysis is performed 
 to determine the steel stress in this layer with the compressive strain 
 in the concrete limited to 0.003.</p>

<p class="whs13">&nbsp;</p>

<p>Decks constructed of longitudinally prestressed, transversely post-tensioned 
 voided or solid slab units generally only contain minimal transverse reinforcing 
 ties. &nbsp;Retrofitting 
 bridges with this type of deck will not be permitted after January 1, 
 2010. &nbsp;For 
 these type bridges, the strength checks of the deck at the gutter line 
 will not be required. &nbsp;Only 
 Index No. 776 or Index 780 Series retrofits should be used to retrofit 
 these bridges.</p>

<p>&nbsp;&nbsp;</p>

<p>In addition to checking the existing deck capacity at the gutter line, 
 the following minimum areas of reinforcing steel per longitudinal foot 
 of span must also be satisfied unless a more refined analysis is performed 
 to justify a lesser area of steel at these locations:</p>

<p>&nbsp;</p>

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<col class="whs30">
<col class="whs31">
<col class="whs32">
<col class="whs32">
<col class="whs32">

<tr valign="top" class="whs4">
<td colspan="5" rowspan="1" width="100%" class="whs33">
<p align="center" class="whs18">Minimum Steel Area (in<span style="vertical-align: Super;">2</span>/ft) 
 for Standard Index</td>
</tr>

<tr valign="top" class="whs4">
<td valign="middle" width="24.185%" class="whs34">
<p align="center" class="whs18">Location of Reinforcing Steel</td>
<td valign="middle" width="15.815%" class="whs35">
<p align="center" class="whs18">772,776 &amp; 777</td>
<td valign="middle" width="20%" class="whs36">
<p align="center" class="whs18">773 &amp; 775</td>
<td valign="middle" width="20%" class="whs36">
<p align="center" class="whs18">774</td>
<td valign="middle" width="20%" class="whs36">
<p align="center" class="whs18">780 Series</td></tr>

<tr valign="top" class="whs4">
<td valign="middle" width="24.185%" class="whs37">
<p align="right" class="whs26">Transverse in top of curb beneath post:</p>
<p align="right" class="whs26"><span style="text-align: right;">Grade 33 reinforcing</span></p>
<p align="right" class="whs26">Grade 40 &amp; 60 reinforcing</td>
<td valign="middle" width="15.815%" class="whs38">
<p>&nbsp;</p>
<p>&nbsp;</p>
<p align="center" class="whs22">0.32</p>
<p align="center" class="whs22">0<span style="text-align: center;">.25</span></td>
<td valign="middle" width="20%" class="whs39">
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">0.40</p>
<p align="center" class="whs22">0.31</td>
<td valign="middle" width="20%" class="whs39">
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">0.40</p>
<p align="center" class="whs22">0.31</td>
<td valign="middle" width="20%" class="whs39">
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">NA</p>
<p align="center" class="whs22">NA</td></tr>

<tr valign="top" class="whs4">
<td colspan="1" rowspan="1" valign="middle" width="24.185%" class="whs37">
<p align="right" class="whs26">Vertical in face of curb for thickness &quot;D&quot;</p>
<p align="right" class="whs26">Grade 33 reinforcing</p>
<p align="right" class="whs26">Grade 40 &amp; 60 reinforcing</td>
<td colspan="1" rowspan="1" valign="middle" width="15.815%" class="whs38">
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">0.20</p>
<p align="center" class="whs22">0.20*</td>
<td colspan="1" rowspan="1" valign="middle" width="20%" class="whs39">
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">2.25/(D-2)**</p>
<p align="center" class="whs22">1.80/(D-2)**</td>
<td colspan="1" rowspan="1" valign="middle" width="20%" class="whs39">
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">2.65/(D-2)**</p>
<p align="center" class="whs22">2.10/(D-2)**</td>
<td colspan="1" rowspan="1" valign="middle" width="20%" class="whs39">
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">&nbsp;</p>
<p align="center" class="whs22">3.30/(D-2)**</p>
<p align="center" class="whs22">2.60/(D-2)**</td></tr>

<tr valign="top" class="whs4">
<td rowspan="1" colspan="5" valign="middle" width="24.185%" class="whs37">
<p>* &nbsp;&nbsp;0.16 
 sq inches/foot is acceptable for D equal to or greater than 15-inches.</p>
<p>** Minimum area of reinforcing steel must not be less than 0.16 square 
 inches/foot.</p>
<p>Where: <span style="margin-left: 36px;">D (inches) = Horizontal thickness 
 of the curb at the gutter line.</span></td>
</tr>
</table>

<p>&nbsp;</p>

<p>If the minimum areas of reinforcing in the curb given above are not 
 satisfied, the following design values may be used for a refined analysis 
 of the existing curb beneath the post for the Index 770 Series retrofits:</p>

<p>&nbsp;</p>

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<p align="center" class="whs22"><span style="font-weight: bold;"><B>Traffic Railing Type</B></span></td>
<td valign="middle" width="25%" class="whs19">
<p align="center" class="whs18">Standard Index No.</td>
<td valign="middle" width="25%" class="whs19">
<p align="center" class="whs40">M<span style="vertical-align: Sub;">p</span> &nbsp;</td>
<td valign="middle" width="25%" class="whs19">
<p align="center" class="whs40">T<span style="vertical-align: Sub;">u</span></td></tr>

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<td valign="middle" width="25%" class="whs21">
<p align="center" class="whs22">Thrie-Beam Retrofit</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">Nos. 772, 776 &amp; 777</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">9.7 </td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">7.9</td></tr>

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<td valign="middle" width="25%" class="whs21">
<p align="center" class="whs22">Thrie-Beam Retrofit</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">Nos. 773, 774 &amp; 775&#9;</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">12.0</td>
<td valign="middle" width="25%" class="whs23">
<p align="center" class="whs22">9.9</td></tr>
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<p>&nbsp;</p>

<p><span style="font-weight: bold;"><B>M</B></span><span style="vertical-align: Sub; font-weight: bold;"><B>p</B></span> 
 (kip-ft/ft) - Ultimate deck moment in the curb at centerline of post from 
 the traffic railing impact.</p>

<p class="whs14">&nbsp;</p>

<p><span style="font-weight: bold;"><B>T</B></span><span style="vertical-align: Sub; font-weight: bold;"><B>u</B></span> 
 (kip/ft) &nbsp;&nbsp;&nbsp;&nbsp;- 
 Total ultimate tensile force to be resisted.</p>

<p>The following relationship must be satisfied in the curb at centerline 
 of post:</p>

<p>&nbsp;</p>

<table x-use-null-cells cellspacing="0" width="100%" class="whs15">
<col class="whs3">
<col class="whs3">

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<td valign="middle" width="50%" class="whs41">
<p><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>(T</B></font></span><span style="font-weight: bold;
	font-size: 11pt;
	vertical-align: Sub;"><font size=3 style="font-size:11pt;"><B>u</B></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B> 
 / </B></font></span><span style="font-style: italic;
						font-weight: bold;
						font-size: 11pt;"><font size=3 style="font-size:11pt;"><I><B>&#934;</B></I></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>P</B></font></span><span 
 style="vertical-align: Sub;
		font-weight: bold;
		font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>n</B></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B> 
 )+ (M</B></font></span><span style="vertical-align: Sub;
							font-weight: bold;
							font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>u</B></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B> 
 / </B></font></span><span style="font-style: italic;
						font-weight: bold;
						font-size: 11pt;"><font size=3 style="font-size:11pt;"><I><B>&#934;</B></I></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>M</B></font></span><span 
 style="vertical-align: Sub;
		font-weight: bold;
		font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>n</B></font></span><span style="font-weight: bold; font-size: 11pt;"><font size=3 style="font-size:11pt;"><B>) 
 &#8804; 1.0</B></font></span> </td>
<td valign="middle" width="50%" class="whs25">
<p align="right" class="whs26">(Eq 6-2)</td></tr>
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<p>&nbsp;</p>

<p class="whs42"><span style="font-style: normal;
											font-weight: normal;
											font-family: Arial, sans-serif;
											font-size: 10pt;"><font size=2 style="font-size:10pt;">Where:</font></span> 
 </p>

<p class="whs42">&nbsp;</p>

<p class="whs43">Ø &nbsp;= 
 1.0</p>

<p class="whs44">&nbsp;</p>

<p class="whs45"><span style="font-style: normal;
												font-family: Arial, sans-serif;
												font-size: 10pt;"><font size=2 style="font-size:10pt;">P</font></span><span 
 style="font-style: normal;
		font-family: Arial, sans-serif;
		vertical-align: Sub;
		font-size: 10pt;"><font size=2 style="font-size:10pt;">n</font></span><span style="font-style: normal;
												font-family: Arial, sans-serif;
												font-size: 10pt;"><font size=2 style="font-size:10pt;"> = A</font></span><span 
 style="vertical-align: Sub;
		font-style: normal;
		font-family: Arial, sans-serif;
		font-size: 10pt;"><font size=2 style="font-size:10pt;">s</font></span><span style="font-style: normal;
												font-family: Arial, sans-serif;
												font-size: 10pt;"><font size=2 style="font-size:10pt;">f</font></span><span 
 style="vertical-align: Sub;
		font-style: normal;
		font-family: Arial, sans-serif;
		font-size: 10pt;"><font size=2 style="font-size:10pt;">s</font></span> <span style="font-style: normal;
												font-weight: normal;
												font-family: Arial, sans-serif;
												font-size: 10pt;"><font size=2 style="font-size:10pt;">(kips/ft) 
 - Nominal tensile capacity based on the areas of transverse reinforcing 
 steel in both the top and bottom of the curb (A</font></span><span style="vertical-align: Sub;
	font-style: normal;
	font-weight: normal;
	font-family: Arial, sans-serif;
	font-size: 10pt;"><font size=2 style="font-size:10pt;">s</font></span><span style="font-style: normal;
											font-weight: normal;
											font-family: Arial, sans-serif;
											font-size: 10pt;"><font size=2 style="font-size:10pt;">)and the 
 nominal steel strength (f</font></span><span style="vertical-align: Sub;
												font-style: normal;
												font-weight: normal;
												font-family: Arial, sans-serif;
												font-size: 10pt;"><font size=2 style="font-size:10pt;">s</font></span><span 
 style="font-style: normal;
		font-weight: normal;
		font-family: Arial, sans-serif;
		font-size: 10pt;"><font size=2 style="font-size:10pt;">). &nbsp;This 
 reinforcing steel must be fully developed at the critical section.</font></span></p>

<p class="whs14">&nbsp;</p>

<p><span style="font-weight: bold;"><B>M</B></span><span style="vertical-align: Sub; font-weight: bold;"><B>u</B></span> 
 = Total ultimate moment in the curb from traffic railing impact and factored 
 dead load at centerline of post <span style="font-weight: bold;"><B>(M</B></span><span 
 style="vertical-align: Sub; font-weight: bold;"><B>p</B></span><span style="font-weight: bold;"><B> 
 + 1.25*M</B></span><span style="vertical-align: Sub; font-weight: bold;"><B>Dead 
 Load</B></span><span style="font-weight: bold;"><B>)</B></span> (kip-ft/ft).</p>

<p>&nbsp;</p>

<p><span style="font-weight: bold;"><B>M</B></span><span style="vertical-align: Sub; font-weight: bold;"><B>n</B></span> 
 = Nominal moment capacity of the curb at centerline of post determined 
 by traditional rational methods for reinforced concrete (kip-ft/ft). The 
 bottom layer of steel in the curb must not be included unless a strain 
 compatibility analysis is performed to determine the steel stress in this 
 layer with the compressive strain in the concrete limited to 0.003.</p>

<p>&nbsp;</p>

<p>The ultimate moment capacity of existing wing walls and retaining walls 
 supporting the traffic railing retrofits must not be less than 9.7 kip-ft/ft 
 for Index 770 Series retrofits (3-1 ½ maximum post spacing) and 12.0 kip-ft/ft 
 for Index 780 Series retrofits. Wing walls for Index 780 Series retrofits 
 must also be a minimum of 5 feet in length and pile supported. For Index 
 780 Series retrofits only, wing walls that do not meet these criteria 
 must not be used to anchor the ends of guardrail transitions and must 
 be shielded by continuous guardrail as shown on the <span style="font-weight: bold; font-style: italic;"><I><B>Structures 
 Standard Drawings</B></I></span>. For both 770 and 780 Series retrofits, retaining 
 walls must be continuous without joints for a minimum length of 10 feet 
 and adequately supported to resist overturning.</p>

<p>&nbsp;</p>

<p>An exception will be required for bridges or components of bridges that 
 do not meet the preceding strength requirements. The potential for damage 
 to the existing bridge deck or wing walls due to a very severe crash, 
 such as that modeled by full scale crash testing, may be acceptable in 
 specific cases. Contact the Structures Design Office for additional guidance 
 and assistance in these cases.</p>

<h3><a name=6.4.5>6.7.5 Historic Bridges</a></h3>

<p class=OutlineA>A. Federal Law protects Historic Bridges and special 
 attention is required for any rehabilitation or improvement of them. The 
 Director of the Division of Historical Resources of the Florida Department 
 of State serves as Florida's State Historic Preservation Officer (SHPO). 
 The SHPO and FDOT are responsible for determining what effect any proposed 
 project will have on a historic bridge. &nbsp;<a 
 href="http://www.fdot.gov/roadway/PPM Manual/2003/Print PPM/By Chapter/Volume 1/V1Chap26.pdf"
	target=_blank>See the <span style="font-weight: bold; font-style: italic;"><I><B>PPM</a> 
 Chapter 26.</B></I></span></p>

<p class=OutlineA>B. Bridges that are designated historic or that are listed 
 or eligible to be listed in the National Register of Historic Places present 
 a special railing challenge because the appearance of the bridge may be 
 protected even though the historic railing may not meet current standards. 
 When a project is determined to involve a historically significant bridge, 
 the District should contact the Structures Design Office for assistance 
 with evaluating the existing bridge railings.</p>

<p class=OutlineA>C. Original railing on a historic bridge is not likely 
 to meet: </p>

<p class=OutlineA1>1.) Current crash test requirements.</p>

<p class=OutlineA1>2.) Current standards for railing height (a minimum 
 of 32 inches for Test Level 4) and for combination traffic and pedestrian 
 railings, </p>

<p class=OutlineA1>3.) Current standards for combination traffic and pedestrian 
 railings, e.g. a minimum height of 42 inches and the limit on the size 
 of openings in the railing (small enough that a 6 inch diameter sphere 
 cannot pass.) </p>

<p class=OutlineA>D. Options for upgrading the railing on historic bridges 
 usually include the following:</p>

<p class=OutlineA1>1.) Place an approved traffic railing inboard of the 
 existing railing, leaving the existing railing in place. This is sometimes 
 appropriate when a pedestrian walkway exists on or is planned for the 
 bridge.</p>

<p class=OutlineA1>2.) Replace the existing railing with an approved, acceptable 
 railing of similar appearance.</p>

<p class=OutlineA1>3.) Remove the current railing and incorporate it into 
 a new acceptable railing. This may be appropriate in rare instances where 
 an existing railing is especially decorative.</p>

<p class=OutlineA1>4.) Design a special railing to match the appearance 
 of the existing railing. It may not be necessary to crash test the new 
 railing if the geometry and calculated strength equal or exceed a crash 
 tested traffic railing.</p>

<h3><a name=6.4.51
		style="font-weight: bold;">6.7.6 Requirements for Test Levels 5 
 and 6 [13.7.2]</a> </h3>

<p class=OutlineA>A. Consider providing a traffic railing that meets the 
 requirements of Test Levels 5 or 6 when any of the following conditions 
 exist:</p>

<p class=OutlineA1>1.) The volume of truck traffic is unusually high.</p>

<p class=OutlineA1>2.) A vehicle penetrating or overtopping the traffic 
 railing would cause high risk to the public or surrounding facilities.</p>

<p class=OutlineA1>3.) The alignment is sharply curved with moderate to 
 heavy truck traffic.</p>

<p class=OutlineA>B. Contact the SDO for guidance if a Test Level 5 or 
 6 traffic railing is being considered.</p>

<h3><a name=6.4.511
		style="font-weight: bold;">6.7.7 Exceptions</a> </h3>

<p class=OutlineA>A. In the rare event that an upgrade to the traffic railing 
 on an existing bridge could degrade rather than improve bridge safety, 
 during the early phases of a project consult the Structures Design Office 
 about a possible design exception.</p>

<p class=OutlineA
	style="margin-left: 24px; text-indent: -24px;">B. Factors to consider 
 include the following:</p>

<p class=OutlineA1>1.) Remaining time until scheduled replacement or major 
 rehabilitation of structure.</p>

<p class=OutlineA1>2.) Design speed and operating speed of traffic in the 
 structure location, preferably no greater than 45 mph.</p>

<p class=OutlineA1>3.) Resistance to impact of the existing railing.</p>

<p class=OutlineA1>4.) Whether the structure ends are intersections protected 
 by stop signs or traffic signals.</p>

<p class=OutlineA1>5.) Whether the geometry is straight into, along and 
 out of the structure.</p>

<p class=OutlineA1>6.) Overall length of the structure.</p>

<p class=OutlineA1>7.) Whether traffic on the structure is one-way or two-way.</p>

<p class=OutlineA1>8.) Accident history on the structure, including damages 
 to and repairs of the existing railing.</p>

<p class=OutlineA1>9.) Risk of fall over the side of the structure.</p>

<p class=OutlineA1>10.) Whether the bridge has an intersecting roadway 
 or railroad track below.</p>

<p class=OutlineA1>11.) Whether a railing upgrade will further narrow an 
 already narrow lane, shoulder or sidewalk.</p>

<p class=OutlineA1>12.) Load rating of the existing bridge.</p>

<p class=OutlineA1>13.) Special historic or aesthetic concerns.</p>

<p class=OutlineA>C. Exceptions to the requirements of this Article must 
 be approved in accordance with <a href="http://www.fdot.gov/roadway/PPM Manual/2003/Print PPM/By Chapter/Volume 1/V1Chap23.pdf"
									target=_blank>Chapter 23 of the <span 
 style="font-weight: bold; font-style: italic;"><I><B>Plans Preparation Manual</B></I></span>, 
 Volume I</a>.</p>

<h3><a name=6.4.5111
		style="font-weight: bold;">6.7.8 Sound Barriers</a> </h3>

<p class=OutlineA>A. Do not attach sound barriers to the top of traffic 
 railings unless the system has been crash tested and meets TL-4 acceptability 
 requirements of <span style="font-style: italic; font-weight: bold;"><I><B>NCHRP 
 Report 350</B></I></span>. &nbsp;</p>

<p class=OutlineA>B. Non-crash tested sound barriers may be attached to 
 structures if located behind an approved traffic railing and mounted at 
 least five feet from the face of the traffic railing at deck level. &nbsp;</p>

<p class=OutlineA>C. The Traffic Railing Barrier/Sound wall, Structures 
 Standard Index Nos. 1550, 1560 and 1570 are crash tested and approved 
 for TL-4 use.</p>

<h3 class=OutlineA><a name=6_7_9></a><a name=6.4.51111
										style="font-weight: bold;">6.7.9 
 Sidewalks</a> <span style="font-size: 10pt;"><font size=2 style="font-size:10pt;"><A href="javascript:void(0);" onclick="BSSCPopup('SDG_6.7_Traffic_Railing_text2.htm');return false;" onMouseOver="if (parseInt(navigator.appVersion) >= 4) BSPSPopupOnMouseOver(event);" class="popupspot" >(01/06)</a></font></span></h3>

<p>Design bridges with sidewalks located behind traffic railings for the 
 governing of the following two cases:</p>

<p class=OutlineA1>1. The initial design configuration with traffic load, 
 pedestrian load, traffic railing and pedestrian railing loads present, 
 or,</p>

<p class=OutlineA1>2. &nbsp;The 
 possible future case where the traffic railing between the travel lanes 
 and the sidewalk is removed and vehicular traffic is placed over the entire 
 deck surface (no pedestrian loads present).</p>

<p class="whs9">Commentary:</p>

<p class="whs9">In the future, the sidewalk could be simply 
 eliminated in order to provide additional space to add a traffic lane. 
 &nbsp;For this 
 case two options are viable:</p>

<p class=OutlineA1
	style="font-style: italic;">1. Construct a second traffic railing at 
 the back of the sidewalk instead of a standard Pedestrian / Bicycle Railing 
 as part of the original bridge construction. &nbsp;A 
 vertical face traffic railing is preferred for this application if ADA 
 compliant handrails are required due to the grade of the sidewalk. &nbsp;Design 
 the cantilever within the sidewalk deck area to resist vehicle impact 
 forces and wheel loads.</p>

<p class=OutlineA1
	style="font-style: italic;">2. Construct a standard Pedestrian / Bicycle 
 Railing as part of the original construction of the bridge and then demolish 
 it and replace it with a traffic railing when necessary. &nbsp;If 
 the deck cantilever is adequately reinforced to resist vehicle impact 
 forces and wheel loads, only the railing needs to be replaced. &nbsp;Dowel 
 the new vertical steel into the deck.</p>

<p>&nbsp;</p>

<p>&nbsp;</p>

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