REHABILITATION FEASIBILITY REPORTDiagonal L3-U4 not connected to L3 Grid deck deterioration deterioration FIGURE 1 – TRUSS DETERIORATION Typical joint and congestion Bowing diagonal

REHABILITATION FEASIBILITY REPORT

KELLY ROAD BRIDGE LOCAL ROAD T-388 (KELLY ROAD)

OVER SHENANGO RIVER

MERCER COUNTY BRIDGE NO. 2304

PREPARED FOR: MERCER COUNTY AND

PENNSYLVANIA DEPARTMENT OF TRANSPORTATION DISTRICT 1-0

PREPARED BY:

December 2011

REHABILITATION FEASIBILITY REPORT KELLY ROAD BRIDGE (NO. 2304)

OVER SHENANGO RIVER MERCER COUNTY

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TABLE OF CONTENTS

INTRODUCTION …………………………………………………………………...........1

PROJECT PURPOSE ……………………………………………………………..1 PROJECT NEED ………………………………………………………………….1

BRIDGE DESCRIPTION AND HISTORY ………………………………………………2 BRIDGE CONDITION …………………………………………………………………...4 REHABILITATION ANALYSIS ………………………………………………………...7

DESIGN/ANALYSIS CRITERIA………………………………………………...7 EXISTING BRIDGE ANALYSIS ………………………………………………..8 REHABILITATED BRIDGE ……………………………………………………..9 REHABILITATION COSTS…………………………………………………….13

SMART TRANSPORTATION ………………………………………………………….13 CONCLUSION …………………………………………………………………………..14 LIST OF TABLES TABLE OF CONDITION RATINGS FOR KELLY ROAD BRIDGE …………………..4 TABLE OF VEHICLE RATINGS FOR KELLY ROAD BRIDGE ……………………...8 FUNCTIONAL AND OPERATIONAL ADEQUACY EVALUATION OF REHABILITATED BRIDGE………………………………………………………... ….12 SMART TRANSPORTATION EVALUATION……………………………………….. 13 LIST OF FIGURES FIGURE 1 – TRUSS DETERIORATION ………………………………………………..6 FIGURE 2 – TRUSS ELEVATION AND REHABILITATION SCHEME...………......10



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INTRODUCTION This Rehabilitation Feasibility Report has been developed to address the potential for rehabilitation of the existing Kelly Road (truss) bridge as part of the Determination of Effect Report, and to support the purpose and needs of the proposed project. The feasibility of rehabilitating the existing truss bridge presented herein was considered and presented as part of the public meeting process where project alternatives were discussed with the general public and Section 106 consulting parties. This Report is developed in accordance with the Advisory Council on Historic Preservation, Section 106 Regulations and PennDOT's November 2010 Cultural Resources Handbook (Publication 689), Section XII.A.6. Additionally, the March 2007 AASHTO publication, Guidelines for Historic Bridge Rehabilitation and Replacement is applied to facilitate the rehabilitation evaluation process as described throughout this report. Project Purpose The purpose of this project is to identify a feasible, cost-effective transportation solution that provides a safe and dependable crossing of the Shenango River for local residents, emergency vehicles, school buses, local delivery trucks and recreational travelers. The project solution will maintain the only access to the Shenango River Dam, the Shenango River boat launch and recreational area, and the local residences. Project Need The project need is to address the structural and functional deficiencies of the existing bridge(s) by improving traffic and roadway safety, bridge geometry and load carrying capacity. The Kelly Road Bridge carrying T-388 is the only access across the Shenango River to several residences, the Shenango Dam and other public recreational facilities; without the Kelly Road Bridge, this community and these facilities are inaccessible (see Photo 1). The existing facility carrying Kelly Road over the Shenango River is comprised of two independent yet adjacent bridge structures (see Photo 2): a single-span truss bridge (the subject bridge) and a two-span steel beam bridge (Mercer County Bridge No. 2303). The subject single span truss bridge is 114 years old and is currently closed to all vehicular and pedestrian traffic given the presence of broken and significantly deteriorated bridge members and the overall structurally deficient and functionally obsolete condition. The adjacent two-span bridge allows only one lane of traffic and is posted for a 30-ton weight limit due to deterioration and recent significant structural repairs to supporting members. The two-span bridge is labeled as functionally obsolete due the limited travel lane width, shoulder width and legal load carrying capacity. These bridges have an estimated ADT of 412, but more importantly serve as the only access connecting the local residences to the adjacent communities. The useful life of both bridges, and in particular that of the truss span, have been far exceeded.



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Photo 1 - Aerial view showing bridge, the Shenango River/Lake and adjacent Sharpsville community

Photo 2 - View of bridge site looking west

BRIDGE DESCRIPTION AND HISTORY The existing Kelly Road Bridge, constructed in 1897 by the Penn Bridge Company, is a single span, pin-connected Parker thru truss supported by sandstone masonry abutments. The riding surface is a steel open grid deck. The bridge spans 183'-4" from bearing to bearing and is 19'-2" between centers of trusses providing a clear lane width of only



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16'-0". The bridge is a classic combination of steel rolled shapes, riveted built-up laced members, eye bars, and turnbuckle rods. Approximately 15.6' of vertical clearance is provided between the deck and the bottom of horizontal bracing; and 18' of vertical clearance is provided from the bottom bridge chord to normal flow of the Shenango River. The abutments are situated on a 90-degree skew angle measured to the bridge centerline. Kelly Road (T-388) is classified as a rural local road with an ADT of 412 vehicles per day (4% truck traffic) and a posted speed limit of 25 mph. The rehabilitation history of the Kelly Road Bridge is significant with regard to defining changes to the original bridge configuration and the components that have been replaced and/or updated throughout the useful life of the bridge. A timeline and details for previous bridge rehabilitations are as follows:

• Rehabilitated in 1921 – work included the following: 1. Remove and replace plank floor, floorbeams and stringers, one end post,

hand railing, and backwall, 2. Painting of all new structural steel.

• Full bridge cleaning and repainting in 1930.

• Rehabilitated in 1959 – work included the following:

1. Install new floor system (floor beams, stringers and steel grid deck with curbs),

2. Repair of post and hanger at each lower panel point, 3. Reinforce eye-bars, 4. Remove concrete encasement at end posts, 5. Replace truss expansion bearing with self-lubricating plate assemblies, 6. Place new stringer bearings at the expansion end, 7. Replace in kind, where badly rusted, portal bracing and top and

intermediate lateral connections, 8. Stiffen existing railing, 9. Replace rivets as required. Note that based upon estimated quantities indicated in the rehabilitation plans, approximately 40% of the original material was replaced.

• Rehabilitated in 1987 – work included the following: 1. Replaced several sections of the deck, 2. Tightened counters, 3. Replaced lower sway bracing.

The Kelly Road Bridge was permanently closed to all traffic on November 28, 2005 after a routine inspection turned up a failed (broken) truss member.



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The historical significance of the bridge has been established as the bridge is eligible for the National Register of Historic Places. In line with the AASHTO Guidelines Step 1: Understanding What Makes a Bridge Historic, the bridge can be considered of average historical significance due its importance on the state and local levels. The components that demonstrate historical significance include the use of the Parker truss configuration and pin connected joints. Adding to the bridges significance, according to the 1998 Pennsylvania Historic Bridge Survey, is the fact that at the time of the survey approximately only 15 pin connected Parker trusses remained in the state of PA and only three remained that were built before 1900. Though no updated survey information is available, it is possible that these numbers have decreased in the thirteen years since the survey was conducted. BRIDGE CONDITION The condition assessment of the Kelly Road Bridge is based on the November 28, 2005 and the October 27, 2011 Bridge Inspection Reports which label the bridge as fracture critical and results in a structurally deficient bridge with a sufficiency rating of 18.9. A fracture critical bridge is one in which loss of a key supporting member (such as a truss member in the case of the Kelly Road Bridge) could lead to failure and collapse of the structure. A structurally deficient bridge has deterioration on one or more of its major components but is considered safe. The sufficiency rating is a tool used by state and federal agencies to define needs and allocate funding; and is based on a scale of 100 with any bridge rating less than 50 being eligible for federal funding. A rating of "0" implies an entirely insufficient or deficient bridge. The following table details the condition ratings and issues noted during the inspections. A condition rating is based on a scale of 9 to 0 established by the National Bridge Inspection Standards and used during bridge inspection to indicate the general structural condition of each bridge component. A condition rating of 5-9 means the bridge is performing as intended with only minor signs of deterioration. A condition rating of 4 or lower means that deterioration on at least one structural component is advanced and the poor conditions result in the bridge being classified as structurally deficient (as defined above). A "0" rating is for failed components and for bridges out of service and beyond corrective action.

TABLE OF CONDITION RATINGS FOR KELLY ROAD BRIDGE

Bridge Feature Condition Ratings and Inspection Notes Deck Condition Rating: 3

• Serious advanced section loss and deterioration • Open grid with pitting scale and rust – 1/16" section loss on

entire deck • Broken bars with multiple holes throughout deck area



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Superstructure (trusses & floor system)

Condition Rating: 0 • Steel rolled floorbeams – rust and scale present on 65% of

surface, 1/16" section loss on the webs and 1/8" section loss on the flanges typical

• Steel rolled stringers – 1/16" section loss on bottom of all flanges for entire length, 1/16" section loss at the center of the web for all beams and holes in select stringer webs

• Truss members (reference Figure 2 for truss configuration) – member L3-U4 failed (broken), 27 of the remaining 31 diagonals with severe section loss; all verticals with poor quality field welded repairs at lower panel points; portals, lateral struts and top lateral bracing show significant deterioration with one angle supporting the west portal dislodged from the structure and broken welds

• Bearings – rust and scale present at all bearings Substructure (bridge supports)

Condition Rating: 5 • Abutments are in fair condition with all primary structural

elements sound with minor section loss, cracking or spalling Other • Paint condition rating: 1 – intolerable with over 50% of the

bridge with rust and scale • No approach guiderail or guiderail transitions are present, but

are required per current standards Figure 1 illustrates various deteriorated and modified truss components, including the broken diagonal L3-U4. Additional field observations as part of the current project regarding both bridge condition and functional bridge features include the following:

• Current bridge railing and curb are inadequate for vehicular use, particularly considering single lane use and fracture critical nature of the bridge. The current railing will not prevent an errant vehicle from significantly damaging critical truss members (see Photo 3).

• All truss diagonals and vertical members have modifications with poor field welds at joint locations (see Figure 1) from previous repairs and show signs of significant section loss at select locations.

• The truss bottom chords and diagonals show signs of slack (i.e. bowing due to possible compression) at numerous locations suggesting possible redistribution of traditional truss forces and the presence of frozen joint pins.

The AASHTO Guidelines, Step 2: Applying Structural and Functional Considerations, seek to evaluate if the engineering objective of rehabilitating the bridge can be achieved to satisfy the project purpose and need while preserving what makes the bridge historic. With an understanding both the bridges condition and significant components, the rehabilitation approach can be tailored to ensure the historic fabric of the structure is not compromised.



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Field welded plate repairs at the verticals and diagonals

Stringer web deterioration

Diagonal L3-U4 not connected to L3

Grid deck deterioration

FIGURE 1 – TRUSS DETERIORATION

Typical joint deterioration and congestion

Bowing diagonal truss member



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Photo 3 - Substandard bridge railing and curb (looking downstream)

REHABILITATION ANALYSIS Design/Analysis Criteria Generally, it is not reasonable to expect that any historic bridge, particularly those over 100 years old, can meet all current state and federal standards in terms of safety, loading capacity and geometry. However, in part as the only access across the Shenango River to the adjacent community and facilities, it is sensible to evaluate the current truss bridge to some level of standard to ensure the rehabilitated structure meets the needs of the community in a safe and appropriate manner thereby meeting project purpose and need. Current design standards for both new and rehabilitated structures are based on PennDOT Design Manual Part 4 (DM-4) September 2007 Edition, Chapter 5, Rehabilitation Strategies. These strategies for rehabilitation seek to improve existing bridges in terms of remaining service life, design methodology and vehicle load carrying capacity as indicated below.

• Desired Service Life: 50 years minimum in rehabilitated condition • Design methodology: Load and Resistance Factor Design (LRFD) • Design vehicle: PHL-93 (standard Pennsylvania highway loading modeling a

typical tractor trailer) As prescribed by DM-4, and in particular for the substructures of bridges, the minimum load carrying capacity is the HS-20 vehicle (also a typical tractor trailer), which while



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similar in configuration and axle load, is overall lighter than the design vehicle PHL-93. The 2003 AASHTO Guide Manual for Condition Evaluation and Load and Resistance Factor Rating (LRFR) of Highway Bridges specifies the HS-20 vehicle as a legal loading to be evaluated when a bridge fails to demonstrate adequate capacity for standard design vehicle loading. The overall lighter HS-20 vehicle is used in the current bridge analysis to establish capacity and strengthening requirements, in consideration of presumably smaller original design live loads and considering the rural local roadway classification on which smaller and fewer vehicles travel. Existing Bridge Analysis The following rating analysis is based in part on the previous analyses performed by Mercer County presented in the 2003 inspection report. The previous analysis employs Load Factor Design (LFD) methodology with the PennDOT BAR7 analysis program. This analysis is based on field measurements and therefore then known member section losses throughout the bridge. It should be noted this 2003 analysis was conducted prior to truss member L3-U4 breaking and does not include the additional severe deterioration of 28 of the 32 truss diagonals as noted in the recent 2011 inspection report; therefore, the following analysis considers all truss members intact with only previous section deterioration included. Gannett Fleming has reviewed and agrees with the accuracy of the previous 2003 analysis. LRFR methodology (similar to LRFD, but used for rating rather than design) was used to generate the live load ratings for the following legal load rating vehicles:

• H20 – 2 axle truck gross weight 20 tons, • HS20 – 3 axle tractor truck with semi-trailer gross weight 36 tons, • ML80 – 4 axle truck (the maximum legal load in PA) gross weight 37.75 tons, • TK527 – 7 axle truck gross weight 40 tons.

The results of the previous LFD analysis were extracted and manipulated for LRFR criteria to establish the ratings. The following table summarizes the rating results of the rehabilitation analysis and represents operating level ratings as described in the LRFR manual.

TABLE OF VEHICLE RATINGS FOR KELLY ROAD BRIDGE

Vehicle Operating Rating Tonnage Governing

Location H20 0.36 7.2 Tons U4 – L5

HS20 0.36 13.0 Tons U4 – L5 ML80 0.34 12.8 Tons U4 – L5 TK527 0.32 12.8 Tons U4 – L5



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The ratings indicate the ability of a bridge component to carry vehicular live load relative to the dead load (permanent load) carried by the same component. A value less than unity indicates there is not enough structural capacity to carry the prescribed full live load. The tonnage values indicate the maximum load for each vehicle type that may utilize the structure without causing permanent deformation to the truss members, which are shown to be significantly less than their standard gross weights. The sub-unity ratings and low tonnages indicate the need for extensive strengthening to raise the bridge loading limits. Due to the very low ratings shown above (only 36% of the capacity required), and regardless of the level of strengthening and modifications undertaken as part of the rehabilitation, it is apparent the load carrying capacity of the bridge will not achieve the minimum legal loading HS-20 vehicle. It should be noted that only the governing location/component is shown for each vehicle (in this case identical for all cases); however, the analysis shows that many other components throughout the truss are substandard as well. Rehabilitated Bridge With the rating results above and based on the design criteria set forth by PennDOT DM-4 for rehabilitated bridges and those discussed in the AASHTO Guidelines, the following is a breakdown of rehabilitation items required. Figure 2 illustrates the existing truss configuration and the components requiring replacement or strengthening as part of rehabilitation. Superstructure Elements for Replacement

1. All Diagonals (32 members) 2. Select stringers and floorbeams with full section loss 3. Steel grid deck

Superstructure Elements for Strengthening 1. Top Chord and portal end posts L0-U1 thru U10-L11 (22 members) 2. Bottom Chord L0 thru L2, L9 thru L11 (8 members) 3. All Verticals (20 members)

Additional Work Items Anticipated • Clean and paint entire structure. Note that after sandblasting additional repairs

may be required as more deterioration is exposed. Painting will require full environmental protection due to the presence of existing lead-based paints.

• Repairs to the remaining stringers, floorbeams, misc. bracing and associated connections.

• Remove, clean, and test pins. Depending on the outcome of the cleaning and testing, re-install or replace the pins in kind with upgraded materials.

• Replace expansion bearings. • Updates / modifications to existing bridge railing to provide crashworthy

protection on bridge, such as structure mounted guiderail. • Crash attenuators are required for the upstream truss on both approaches in

addition to upgrades of the approach guiderail transitions on the downstream side.



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The geometry at the pin connections precludes adding additional plates, eye-bars or connection plates to improve the ratings as these locations are congested with the current members (see Photo 4). As a result, and in spite of calling for strengthening of various members, replacement of said members with higher strength material and larger sections may be more feasible; particularly once cleaning and sand blasting is completed and the full amount of deterioration is determined for each member and joint pin.

Photo 4 - Typical truss lower chord joint detail

Due to the current condition of the bridge, the rehabilitation will require temporary shoring of the existing structure from abutment to abutment. For example, each floorbeam will require support to maintain the stability of the existing trusses during construction. The use of temporary shoring will prove difficult and costly in order to phase repairs (such as pin removal and chord repairs) throughout the truss while maintaining stability in place. The span length and configuration of the truss, and the lack of capacity of various members to carry both tension and compression forces, precludes full removal of the truss from its supports for rehabilitation in a cost effective manner. A causeway constructed in the Shenango River will also be required to facilitate construction access and activities. No construction loads will be permitted on the existing structure. Therefore, all work must be done from platforms mounted on the temporary shoring or from the causeway. Traffic must be maintained on the adjacent two-span bridge during construction limiting available construction access. Temporary



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closures may be required in order to work on various components of the upstream truss immediately adjacent to the two-span bridge. Based on the rehabilitation items listed above and the manner in which these components can be strengthened or replaced, it is anticipated that the historic fabric of the Kelly Road Bridge can be maintained in the rehabilitated condition. For example, the Parker truss configuration will not change and while pins and truss members may be replaced, it is anticipated these components can be replaced in kind (size and configuration) with higher strength materials. To the contrary, according to the AASHTO Guidelines, components such as standard-design railings, decks, stringers and floorbeams, which are scoped for replacement under the current rehabilitation, are not vital to retain the historical fabric of the truss. As discussed in the AASHTO Guidelines, Step 2, an evaluation of the rehabilitated bridge with regard to its functional and operational adequacy is necessary to determine if the bridge meets the project purpose and need. Functional and operational adequacy is defined by three components: structure condition, load carrying capacity and geometry/safety features. FUNCTIONAL AND OPERATIONAL ADEQUACY EVALUATION OF REHABILITATED BRIDGE

Discussion Meet

Project Purpose?

Meet Project Need?

Structure Condition

The rehabilitated bridge will greatly improve the condition by replacing bad components and by complete bridge painting. Long term maintenance concerns will persists as continued maintenance will be required.

No Yes

Load Carrying Capacity

Even in the rehabilitated condition, member and joint geometry limitations and truss configuration will limit the load carrying capacity of the bridge, requiring a load limit posting lower than standard legal vehicle weights. Project need is satisfied as ultimately the capacity of the bridge will be improved from its current condition.

No Yes

Geometry/Safety The rehabilitated bridge will maintain only one lane of traffic and substandard safety features.

No No



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Rehabilitation Costs Detailed cost estimating of this rehabilitation alternative is beyond the scope of this report and the project. However, based on the 2005 maintenance item costs (inflated for the current project timeframe) and examples of similar truss rehabilitation projects within the state, and including the rehabilitation items discussed above, the approximated rehabilitation cost for the Kelly Road Bridge is $2,000,000. SMART TRANSPORTATION As directed by the Cultural Resources Handbook, Smart Transportation concepts are to be integrated into the bridge rehabilitation analysis. According to PennDOT's Smart Transportation Guidebook (March 2008), the Smart Transportation concept recommends a new approach to roadway planning and design, in which transportation investments are tailored to the specific needs of each project by considering financial, community, land use, transportation, and environmental contexts in the design solution. The following table details how each of the context components factors into rehabilitation of the existing Kelly Road Bridge.

SMART TRANSPORTATION EVALUATION Context

Component Application on Bridge Rehabilitation

Financial

The cost to rehabilitate the Kelly Road truss bridge (not including life-cycle maintenance costs such as future painting) is estimated to be less than the cost for the proposed replacement bridge ($3,200,000). However, considering the cost to upgrade/replace the adjacent two-span bridge as noted in the following section brings the total cost to $4,200,000. Note this cost will not produce a facility that meets capacity and safety criteria as described in this report. The value/price ratio will be low for the rehabilitation alternative as the facility will not meet project purpose and need, and the initial and lifecycle costs are expected to be higher than a new bridge alternative.

Community

This bridge facility is the only access across the Shenango River to a small community of residences, the Shenango Dam and recreational facilities bounded by the Shenango River, the Shenango Lake and railroad tracks. The rehabilitation alternative will limit vehicle size/loading to and from this community, and will maintain current safety concerns for the traveling public. Community input will be evaluated and included as part of the Effect Report.

Land Use Rehabilitation of the existing truss bridge would minimize land use with regard to construction activities, required right-of-way and the final product. Construction activities would require significant



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temporary works in the river.

Transportation

The importance of this project to the local community and the surrounding transportation network cannot be understated as this facility is the only access across the Shenango River. Rehabilitation of the Kelly Road Bridge will maintain access and network connectivity, however, at limited capacity in terms of both vehicle size/weight and volume with single lane traffic. Safety concerns may persist on both the approach roadway and on the rehabilitated bridge.

Environmental

Rehabilitation will preserve the existing bridge, which is eligible for inclusion in the National Register of Historic Places. Significant modifications/strengthening will be required to allow the current bridge to be opened to any vehicular or pedestrian traffic, including railings and truss members. It is anticipated that such modifications can be done in such a fashion to maintain the historic fabric of the structure.

CONCLUSION Historical and environmental considerations as well as the decision-making thresholds with regard to the existing and rehabilitated bridge, as outlined in Steps 3 and 4 of the AASHTO Guidelines, will be further developed as part of the overall Effect Report required by Section 106 and Pub 689. Consideration of other alternatives, such as preserving the bridge by moving the truss to another location, is beyond the scope of this report. However, it is anticipated that any option to move and/or keep the truss would require extensive rehabilitation similar to that defined above to ensure the overall current project purpose and needs are satisfied. It is feasible to consider the presence of the adjacent two-span bridge as providing for the second and needed travel lane. However, this two-span bridge is nearly 50 years old, carries a 30 ton posted load limit, has already received significant structural repairs, and will require significant upgrades or complete replacement in the near future due to its current condition. Based on the October 19, 2010 inspection of this two-span bridge, the cost to replace the bridge in kind is estimated at $2,200,000. Combining this cost with the estimated cost to rehabilitate the subject truss span brings the total cost to $4,200,000 in order to provide an updated functional facility meeting project purpose. Rehabilitating the existing Kelly Road Bridge to meet project needs and improve the overall structural condition and load carrying capacity while maintaining the existing historic fabric is feasible. However given the truss configuration and geometry, it is not feasible to improve the geometry/safety constraints in order to meet project purpose or needs. Project purpose is not satisfied as it is not feasible to improve the load carrying capacity to standard legal vehicle loadings nor is it cost-effective given the initial and long-term maintenance cost requirements.

Documents

REHABILITATION FEASIBILITY REPORTDiagonal L3-U4 not connected to L3 Grid deck deterioration deterioration FIGURE 1 – TRUSS DETERIORATION Typical joint and congestion Bowing diagonal