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31 APPENDIX B Survey Responses
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32 APPENDIX B1 Owners--Respondent Names and Yes or No Questionnaire Answers 1 Type, Paper, Elect, Internet 6 Design Erect. Proc. (E.P.) 20 E.P. Required by Erect. 5 Stage Constr. Problem 18 Poor Implement. E.P. 3 Constr. Spec. Problem 13 Assembly Req. in #1 19 Field Inspection OK 14 Allow Alt. Assembly 12 Det. or Fabr. Prob. 25 Have Steel Expert 16 Prob. Due to E.P. 17 Poor Erect. Proc. 21 State Check E.P. 8 Dif. Def. Problems 4 Stability Problem 15 Allow OS Holes 2 Spec. Provision Phone Number 1 Spec. Rec'd. Respondent 2 Received 11 Flg. b/L 10 Flg. b/t 2 Type State Alabama Randall Mullins 334-242-6015 No No No No No No No No No Yes Yes No No Yes No No Yes Yes No Jim Tribo & Emanuel 501-569-2136 Arkansas Banks 501-569-2251 Yes P No No No Yes No No No No No No Yes No Yes No Yes Yes No No California Lian Duan 916-227-8220 Yes P Yes Yes P Yes No No Yes No No No Yes Yes No No No No No Yes Yes Yes Yes Colorado Mark Leonard 303-757-9309 Yes I Connecticut Erika Smith 860-258-0701 No No No Yes Yes Yes Yes No No Yes Yes Yes Yes No No No Yes Yes Yes No Florida Steve Platkin 850-414-4155 Yes P Yes Yes P Yes Yes Yes No Yes No No Yes Yes Yes Yes Yes Yes Yes No No No Georgia Reggie Fry 404-363-7619 Yes P No No Yes Yes No No No No No No Yes Yes Yes Yes Yes Yes Yes No No Yes Illinois Jon Edwards 217-782-3586 No Y/N No No No Yes Yes Yes No No No Yes Yes Yes No No Yes No Yes Kansas Richard Mesloh 785-368-7175 Yes P Yes Yes P Yes Yes Yes No Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes No No No Kentucky Steve Goodpaster 502-564-4560 Yes P Yes Yes P No Yes No No No No No Yes Yes Yes No No Yes Yes Yes No Louisiana Kian Yap 225-379-1330 Yes E No Yes Yes Yes No Yes No No Yes Yes Yes Yes Yes No No Yes No Yes Yes Maine Dennis Dubois 207-624-3406 Yes E No No No No No No Yes Yes Yes Yes No Yes Yes Yes Yes Yes No Yes Manitoba Sam Donachuk 204-945-3373 Yes P Yes Yes P No No No Yes No No No No Yes Yes No No Yes Yes Yes No Minnesota Paul Kivisto 651-747-2130 Yes P Yes Yes P No Yes No Yes No Yes Yes Yes Yes Yes Yes Yes Yes Yes Mississippi Harry Lee James 601-359-7200 Yes P No No No No No No No No No Yes Yes No No Yes Yes Yes Yes Yes Yes No Missouri Shelly Schaefer 573-751-3853 Yes P No No No No No No No No Yes No Yes Yes No Yes No No Yes No No Yes Montana William Fullerton 406-444-6261 Yes P No Yes No Yes No Yes No Yes No Yes Yes No No No No Yes No No No N. Dakota Larry Schwartz 701-328-4446 Yes P No No No Yes No No No No No No Yes No No No No No Yes No No No Nebraska Vince Koenig 402-479-3972 Yes I No No No No No No No No No No Yes No No No No Yes Yes Yes No Nevada Todd Stefonowicz 775-888-7550 Yes P No No Yes No No Yes No No No Yes Yes Yes No No No Yes Yes Yes No New York Paul Rimmer 518-457-4526 No No No Yes Yes Yes No Yes No Yes Yes Yes Yes No Yes No Yes Yes No Yes Yes
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APPENDIX B1--(Continued) Owners--Respondent Names and Yes or No Questionnaire Answers 1 Type, Paper, Elect, Internet 6 Design Erect. Proc. (E.P.) 20 E.P. Required by Erect. 5 Stage Constr. Problem 18 Poor Implement. E.P. 3 Constr. Spec. Problem 13 Assembly Req. in #1 19 Field Inspection OK 14 Allow Alt. Assembly 12 Det. or Fabr. Prob. 25 Have Steel Expert 16 Prob. Due to E.P. 17 Poor Erect. Proc. 21 State Check E.P. 8 Dif. Def. Problems 4 Stability Problem 15 Allow OS Holes 2 Spec. Provision Phone Number 1 Spec. Rec'd. Respondent 2 Received 11 Flg. b/L 10 Flg. b/t 2 Type State ' Ohio John Randall 614-387-6210 Yes P No No No Yes No No Yes No No Yes Yes Yes Yes Yes No No No Yes Yes No Oklahoma Walter Peters 405-521-2606 Yes P No Yes Yes No No No No No Yes Yes Yes Yes Yes Yes No Yes No No Yes Oregon Nowzar Ardalan 503-986-3345 No No No No No No No No No Yes Yes No No No Yes Yes Yes Yes Pennsylvania Tom Macioce 717-787-7504 Yes E No No Yes No Yes Yes Yes No Yes Yes Yes No Yes Yes Yes Yes Yes Yes Yes Quebec Jocelyn Labbe 418-644-0169 Yes E No No No No No Yes No Yes No No Yes No Yes No No No Yes No No Yes Rhode Island Richard Snow 401-222-2053 Yes I Yes No No No No No No No No No No No Yes No No No Yes Yes Yes No Tennessee Edward Wasserman 615-741-3351 Yes P No Yes Yes No No Yes No No Yes Yes No No Yes Yes No No No No Yes Texas Gilbert Sylva 512-416-2751 Yes E Yes Yes E Yes Yes Yes No Yes No No Yes Yes Yes No Yes Yes Yes No Yes Yes Yes Washington Nathan Brown 360-705-7219 Yes E Yes Yes E Yes No Yes No Yes No No Yes Yes Yes Yes Yes Yes Yes No Yes Yes Yes Wisconsin Craig Wehrle 608-266-8487 Yes P No No Yes Yes No No Yes No No No Yes Yes Yes Yes Yes No Yes Yes Wyoming Greg Fredrick 307-777-4427 No No No Yes No No Yes No No Yes Yes Yes Yes No Yes No No Yes Notes: P = paper; I = Internet. 33
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34 APPENDIX B2 Owners--Written Questionnaire Responses State Question Comment Connecticut 1 Will be mailed separately; see reply to Question 31. Note: For item 1 above, specifications are available online at http://www.dot.state.il.us/desenv/pdfspec2002/sec500.pdf. Section 500 covers Illinois 1 structures and Section 505 is limited to steel structures. A copy of Section 505 is being mailed, but you may wish to refer to the website for Section 506 on painting steel structures and Section 1006 for metal materials. Louisiana 1 (Please see attached file in the e-mail.) Section 807, pp. 600643. Nevada 1 Section 506 attached. Florida 3 Charles Boyd (850) 414-4275 Kansas 3 Usually survey problems. Some overhang screed brackets. Louisiana 3 Mr. Allen (225) 379-1565 Tennessee 3 But not attributable to construction specs. Texas 3 Brian D. Merrill (512) 416-2232, e-mail: email@example.com Connecticut 4 Tom Ryan (860) 563-9375, e-mail: firstname.lastname@example.org Florida 4 Charles Boyd (850) 414-4275 Illinois 4 None known. John Jones (785) 296-2066, e-mail: email@example.com, and any other available information. The KDOT Bridge Office, in conjunction with Kansas 4 Kansas University, has developed software, "Torsional Analysis of Exterior Girders (TAEG 2.0)" in an attempt to predict the torsional resistance of the exterior girder when it is eccentrically loaded with the screed machine and deck overhang concrete. Kentucky 4 Steve Waddle (502) 564-4780, e-mail: firstname.lastname@example.org Minnesota 4 Bridge #27121 joints cracking in deck due to large deflection. N. Dakota 4 Deck overhang forms deflected more than anticipated. Additional temporary bracing had to be added to box girders on a project due to temperature variations from one side to the other during Nevada 4 erection. Integral abutments supported on bolts to achieve a rotation point. Bolts support beam ends supplied wood blocking on future jobs. Sketch Ohio 4 supplied showing bolts projecting above concrete and double nutted supporting the beam. Pennsylvania 4 See Lehigh University Fritz Engineering Laboratory Report 519.2 May 1995 and International Bridge Conference Paper IBC 88-52. Tennessee 4 Ed Wasserman, Mitch Hiles (615) 741-3351, e-mail: Ed.Wasserman@state.tn.us, Mitch.Hiles@state.tn.us Texas 4 Brian D. Merrill (512) 416-2232, e-mail: email@example.com Wyoming 4 Web distortion of exterior girder when cantilever exceeds girder depth. Connecticut 5 Tom Ryan (860) 563-9375, e-mail: firstname.lastname@example.org Florida 5 Charles Boyd (850) 414-4275
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APPENDIX B2--(Continued) Owners--Written Questionnaire Responses State Question Comment Years back, location and contact not known. During stage construction of a 4-girder bridge, 2 girders in Stage 1 moved laterally about 8 in. during deck pour. Could not move back with hardened deck in place after Stage 2 steel erected, so had to either make special diaphragms and Illinois 5 forms or tear off Stage 1 deck (not sure which happened). Subsequently, ILDOT adopted policy of at least 3 girders in Stage 1 (Stage 2 can be braced against Stage 1), and strong preference for 6 lines where future stage redecking may be needed. Not economical, but reduces lateral motion. Kansas 5 Difficulty installing frames due to differences in girder elevations between Phase I and Phase II. Louisiana 5 Mr. Allen (225) 379-1565 Ohio 5 Hard to control delta deflection between phases. Use a construction closure pour or Phase III between Phases I and II. Texas 5 Brian D. Merrill (512) 416-2232, e-mail: email@example.com Florida 6 Charles Boyd (850) 414-4275 The critical elements that the contractor must know are stated on the design plans. The contractor is responsible for the erection process. Alabama 7 However, he is required to submit an erection plan with calculations stamped by a P.E. Arkansas 7 No information. California 7 To ensure that the design requirements are satisfied during construction stages. Comment: Temporary shoring/bracing or the placement of larger diaphragms to accommodate erection stresses are common. Also, to Connecticut 7 address safety concerns of contractors. Florida 7 The more sophisticated, the higher the level of review and submittal of procedures for review. Georgia 7 Generally, we just make sure that there is a way to build the bridge; i.e., ensure there is enough room for false bents, access, etc. 505.08 (e) of the ILDOT specifications requires submittal of an erection plan, but I do not think this is routinely enforced or evaluated on Illinois 7 typical bridges. The Bureau of Bridges looks at them for major and unique structures. (Sorry, no "sample" available for Question 6.) Kansas 7 May require more geometric control and contract plan notes. Constructibility issues may require a pre-bid conference. Louisiana 7 Shop assembly is required for complex structures. Maine 7 None Manitoba 7 Could complicate erection and require a higher degree of engineering during construction phase. Missouri 7 Not so much on erection, but in fabrication and preparation of shop drawings. Montana 7 More refined designs are harder to construct. For typical projects--minimal impact. Bigger impact for atypical or major projects where a more thorough constructibility review is Nevada 7 performed or where erection issues warrant a detailed analysis. Contractor may need to develop strategies out of the norm to accomplish the erection. Innovative techniques can be evaluated at New York 7 construction. Ohio 7 Currently contractor must develop erection procedure. CMS 501.06. 35
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36 APPENDIX B2--(Continued) Owners--Written Questionnaire Responses State Question Comment Oklahoma 7 Assumptions made in design must be consistent with erection procedures, especially on complex curved and skewed bridges. Some of the designs push the steel sections to such limits that the girders become too limber, hence making them problematic in the areas of Oregon 7 stability and constructibility. The sophistication of the analysis, such as a 3-D analysis, gives us results of the lateral deflection of the girder. For severely skewed bridges, we have shown this rotation of the girder and required the bridge to be fabricated and erected so that in the final position of the girders after Pennsylvania 7 all dead loads have been applied, the girder webs are plumb. This is primarily done on long-span, sharply skewed structures. See plan sheet submitted for Question 6. Quebec 7 Nothing Tennessee 7 Total impact. Where special design requirements can be impacted by erection, more detailed instructions to the contractor are required. Sophistication of design could potentially have a bearing on the erection practices/procedures. In general, a more sophisticated design would Texas 7 require more sophisticated erection practices/procedures. Not sure what the question means. A strict enforcement of methods and sequences during erection is needed to justify exotic design and contract requirements in this area. Contractors generally prefer latitude. Ensuring that a method is practical and safe is generally sufficient Washington 7 during the design stage (sometimes this requires sophisticated analysis). In other words, a general scheme, suitable for all contractors, is preferred. A specific contractor will need to adjust operations to get the required geometrics to work out. The converse may tend to favor one contractor over another or raise costs needlessly. Wisconsin 7 No comment. (Note: Colorado did not fill out the form. They did send an e-mail with a site to get access to their specifications. They also make the following comments in their e-mail. The comments were not directly addressed to any particular question.) The answers to many of the questions in your survey are contained in these documents. Although I am not returning a completed survey, I Colorado 8 wanted to make these documents, as requested in the first part of the survey, available to you. In the past several years there has not been a great deal of steel girder erection in Colorado. Two of the most significant problems we have had with steel girder erection in the past are poor external diaphragm and cross-bracing fit-up on curved, skewed, steel-box girders due to differential field rotation of the boxes, and occasional field fit-up problems in general on skewed steel girder for drilling bolt holes. Connecticut 8 Tom Ryan (860) 563-9375, e-mail: firstname.lastname@example.org Florida 8 Tom Andres (850) 414-4269 Randy DeBoer was the RE for the Edens/Kennedy (I-90/I-94) interchange in Chicago. A curved bridge over the Kennedy could not be Illinois 8 supported between piers and ended up with significant lateral rotation that could not be corrected as subsequent girders were erected. A number of girders have webs out of plumb in the final structure.
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APPENDIX B2--(Continued) Owners--Written Questionnaire Responses State Question Comment Ken Hurst (785) 296-3761, e-mail: email@example.com, and any other available information. Deck placement sequence on long two-span Kansas 8 structures. Large differential deflection between staged construction. Nevada 8 Have experienced alignment problems during erection of curved girders from opposite supports--not attributed to design issues though. Ohio 8 Occasional design errors; substructure elevation or alignment plan errors. See International Bridge Conference Paper 02-43 and Pennsylvania DOT Research Report FHWA-PA-2002-003-97-04(74). A copy of this Pennsylvania 8 report was furnished to NSBA. Tennessee 8 Ed Wasserman, Mitch Hiles (615) 741-3351, e-mail: Ed.Wasserman@state.tn.us, Mitch.Hiles@state.tn.us Texas 8 John M. Holt (512) 416-2212, e-mail: firstname.lastname@example.org Several long, skewed steel bridges have experienced differential lateral movement of the girder ends, resulting in loss of bearing pin keeper Wyoming 8 plates at the abutments. Alabama 9 We are concerned and we reference AISC manual for the end cuts. Arkansas 9 We do not treat curved or skewed bridges differently than straight square bridges. Connecticut 9 DESCUS and STAAD analysis. Also, Bridge Software Development International, Ltd (BSDI) has been used. Florida 9 The following computer programs are used during design: Simon, MDX, BSDI. Georgia 9 No, not usually a concern. Have required finite-element grid analysis of girderbracing system to design crossframes. Unfortunately, this has resulted in very heavy Illinois 9 bracing connections when out-to-out with high skews and curve. Kansas 9 STAAD Model, TAEG 2.0. Louisiana 9 Pending on software. Manitoba 9 Direct stiffness method through programs such as BRASS and STAAD. We only calculate tilts at expansion devices to enable proper placement of the device. If we need to look at deflections other than dead and Missouri 9 live loads, we would need to use a finite-element program (SAP 2000) to check, which we normally do not do. Nevada 9 Have not done this. New York 9 Designer dependent. Ohio 9 MerlinDash, WinDescus; normally, very simple structures. Oklahoma 9 Normal practice is NOT to use any finite elements except for curved girders. We typically use two-dimensional frame analysis using WinStrudl software. On highly skewed or curved girders we use three-dimensional Oregon 9 analysis using the same software. Pennsylvania 9 The most used program used is BSDI 3-D system. Quebec 9 3-D 37
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38 APPENDIX B2--(Continued) Owners--Written Questionnaire Responses State Question Comment Rhode Island 9 Blank Tennessee 9 Line analysis for straight. Grid analysis/frame analysis for curved I-girder closed torsion for curved box girder. Texas 9 Use a grid analysis. Washington 9 gtstrudl or similar--space frame analysis. Wisconsin 9 Computers "Flanges for welded beams shall also be proportioned to give a b/t ratio (flange width/flange thickness) between 12 minimum and 20 Maine 10 maximum with a preferred ratio of 16. These limits are set so as to avoid either a very thin, wide flange that will distort when welded to the web, or a very thick, narrow flange that would be uneconomical to purchase and might be laterally unstable (see L/b ratio in number 11)." "To facilitate handling in the shop and field and during shipping, the L/b ratio (unsupported length of member/compression flange width) for Maine 11 welded beam designs shall preferably not exceed 90. If using an L/b results in an uneconomical flange design, an L/b ratio up to 110 may be used." [Copied from page 800(1) received from Maine.] Minnesota 11 Our current manual does not give requirements; however, our new LRFD manual, which is under development, will use a limit of 80 to 85. Missouri 11 Copy of design information sent. "Unsupported length in compression of the shipping piece divided by minimum flange width, L/b < 85. They also have design recommendations as follows: Montana 11 1. Do not reduce flange thickness at a shop splice by more than 25%; 2. Minimim flange size 12 in. x 7/8 in.; 3. Initial trial design, flange width/web depth 20% to 25%; 4. Max. ship length 125 ft; and 5. Max. ship weight 180,000 lb." Ohio 11 Define minimum flange as 7/8 in. x 12 in. to control fabrication and welding distortion. Connecticut 12 Paul D'Attilio (860) 258-0305, e-mail: email@example.com Illinois 12 None known. Kansas 12 Fill plate sizes. Maine 12 Large skew yields out-of-plumb webs; this has been corrected by detailing accordingly and erecting per shop drawings. Ohio 12 Occasional shop drawing error. More crossframe detail errors. We have had problems on skews with crossframes not fitting and on occasion we have had to use welding in the field instead of bolting as Oklahoma 12 noted in the plans to make the connections. Oregon 12 The problems have been minor and usually are in the area of camber. Pennsylvania 12 Port Vue bridge near Pittsburgh Area and Ford City Bridge. Tennessee 12 Ed Wasserman, Mitch Hiles (615) 741-3351, e-mail: Ed.Wasserman@state.tn.us, Mitch.Hiles@state.tn.us Texas 12 Brian D. Merrill (512) 416-2232, e-mail: firstname.lastname@example.org Misinterpretation of the design cross slope resulted in crossframe connection holes drilled in the incorrect location. The girders were Wyoming 12 subsequently misaligned upon erection and connection of the crossframes.
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APPENDIX B2--(Continued) Owners--Written Questionnaire Responses State Question Comment Florida 13 Very minimum requirements. Mississippi 13 Contact Bridge Engineering for information. California 14 Need RE's approval. Connecticut 14 Alternative methods can be submitted by a contractor for almost any project, but they must be approved. The fabricator may submit alternate methods for approval by the engineer. Minor changes are often approved if deemed equal or better than Georgia 14 specified methods. Depends on structure geometry. For most straight and curved structures, our specs already have latitude for web horizontal or vertical or Illinois 14 Computer Numerical Control (CNC) with spot checks. For special cases, we consider contractor proposals. Strange support geometries may require a change in method. On occasion we allow a reduction in shop assembly complexity, but the Kansas 14 fabricator must "donate" the difference in cost. Based on fabricator's performance. Louisiana 14 Only if the final product stresses and tolerance are within the design limits. Maine 14 Specifications allow alternatives with provisions. Manitoba 14 Fabricator must assume full responsibility for his procedures. Missouri 14 Alternative methods are considered, but must meet minimum of our specifications. Nevada 14 As requested by the fabricator and approved by the department. Ohio 14 See 863.20. Oklahoma 14 The fabricator is required to put the alternative shop assembly in writing, which must be approved by the bridge engineer. Pennsylvania 14 On some projects, High Steel Structures has requested a CNC and template drilling full size for field splices. Texas 14 Alternative shop-assembly methods require approval of the engineer. Simplification is only considered if framing is simple and requirements were overly restrictive. Requirements are generally upheld for Washington 14 complex geometrics. Wisconsin 14 If it makes sense. Certain specifications may be relaxed or alternative methods permitted, generally with the provision that an unsatisfactory product is the Wyoming 14 responsibility of the fabricator to correct or replace. Alabama 15 Unless the design plans show them. Connecticut 15 Contractors can submit a proposal to use oversized holes, which would be reviewed on a project-by-project basis and must be approved. Florida 15 If these holes will ensure proper fit-up with a compromise of stress-carrying capacity. Typically, the crossframes or diaphragms have regular-sized round holes. One connection stiffener has regular-sized round holes and the opposing connection stiffener has slotted holes to facilitate installation. Crossframes and diaphragms are installed with ASTM A307 erection Georgia 15 bolts and then field welded with E7018 low-hydrogen electrodes. Oversized holes would not be detailed when high-strength bolts (ASTM A325 or A490) are used to make the connection. 39
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40 APPENDIX B2--(Continued) Owners--Written Questionnaire Responses State Question Comment Illinois 15 Most cases, unless slight increase is allowable for standard size instead of oversize is needed, or ream assembled (RA) is stipulated in contract. Kansas 15 In only one of the two members. Must be approved on shop drawings. See attached Standard Note. Louisiana 15 High skew and phase construction when possible. Maine 15 See specifications 503.34, next to last paragraph. On occasion, we have considered and used oversized holes in one ply of the connection (usually the crossframe) on structures where Missouri 15 curvature effects are negligible. Nevada 15 Only when erection difficulties are expected. Typical--Oversized with erection bolts in welded crossframes, delta deflection less than 1/2 in. Over 1/2 in. provide slots. Optional-- Oversized with two HS bolts bolted crossframe, delta deflection less than 1/2 in. Over 1/2 in. provide slots. Curved with live load in Ohio 15 crossframes (CVN)--Bolted connections with oversized holes. Reduce allowable bolt friction due to oversized. Standard holes require CVN and full shop assembly. Oversized holes are permitted in crossframe or connection stiffeners for skewed and curved structures. Shop drawings must specify washers Oklahoma 15 for oversized holes. On some skewed bridges we may elect to use vertically slotted holes to permit differential movement between girders during deck placement. Pennsylvania 15 This requires the bolts to be tightened after deck placement, which is an extra construction step. Quebec 15 Only with slip-resistant connections. Washington 15 This has only been allowed for one bolt in a group in case of a misdrilled hole. We always specify holes 1/16 in. larger for these connections. Wisconsin 15 Designer must agree. Wyoming 15 Oversized holes are not allowed in curved girders and in one ply of the crossframes. Illinois 16 None known. Kansas 16 Name: John Jones, and any other available information. Improper bolting procedures. Louisiana 16 Mr. Allen (225) 379-1565 Maine 16 Insufficient alignment effort. Use of inexperienced crew. Minnesota 16 27VC45--Wing girder fit up to straight girder. Mississippi 16 Contact Bridge Engineering for information. Fred Caldwell--Senior Construction Inspector, MoDOT (816) 358-1861. Plate girder over Interstate that part of erection was conducted on Missouri 16 the ground to minimize lane closures. Hamilton County over 75 in Cincinnati--plumbness of webs and alignment of pier on a curved structure due to lack of contractor experience Ohio 16 and department oversight. Port Vue Bridge near Pittsburgh and Ford City Bridge. On a project in State College, an erector walked off the job due to erection Pennsylvania 16 difficulties. Tennessee 16 Ed Wasserman, Mitch Hiles (615) 741-3351, and e-mail: Ed.Wasserman@state.tn.us, Mitch.Hiles@state.tn.us
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APPENDIX B2--(Continued) Owners--Written Questionnaire Responses State Question Comment Texas 16 Brian D. Merrill (512) 416-2232, e-mail: email@example.com We have had an incident in which the contractor dropped a girder as K-bracing was being attached to the adjacent girder. The dropped girder was improperly secured prior to being released from the crane. There was another incident on this same project in which the Georgia 17 contractor erected a span of girders with web verticality problems. The contractor failed to ensure web verticality on the initial girder and transferred the error to each adjacent girder. Illinois 17 None known. Kansas 17 Girders bolted on ground and not blocked properly. Also, bolting splice without the proper use of drift pins and erection bolts. Maine 17 Insufficient bolts to ensure proper alignment; did not verify vertical alignment during erection progress. Mississippi 17 Contractor not following approved erection procedures. Missouri 17 The project had no special erection procedures and process of erecting steel was responsibility of contractor. Ohio 17 Probably needed a note to require plumbness of the web. Reviewers now look for this problem. Most of the problems we have experienced are from a failure to properly support the cantilevers. This results in a twisting of the outside Oklahoma 17 beams and a thinning of the deck slab. It often requires that we add an overlay to correct the ride problems. Oregon 17 I do not see a number 16. Erector on the Port Vue Bridge did not maintain horizontal alignment as the structure was erected. The girders were a maximum 2.625 in. Pennsylvania 17 from straight alignment at the worst points along the girders. The erector had to go back and loosen the crossframes and push the girders into alignment. Texas 17 Problems have been encountered when the contractor deviates from the approved erection plan. Plots of bad flange profiles usually point to kinks at field splices. These have been realigned successfully in most cases if caught soon Washington 17 enough. There were no formal erection procedures; however, the contractor's actions resulted in unacceptable results which were linked to the Georgia 18 implementation of poor erection practices. Illinois 18 None known. Kansas 18 Developed a Bridge Construction Manual to help educate. Maine 18 Erection procedure did not address timely verification of vertical alignment. Minnesota 18 We do not know for sure. Missouri 18 See Question 17--Missouri. Ohio 18 Combination of substructure layout and contractor experience. In the State College project, the erector never completed a comprehensive erection procedure for the bridge. He started erecting the structure Pennsylvania 18 and ran into difficulties. Texas 18 As noted in the previous question, improper implementation can occur when contractor seeks and gains a variance from the approved plan. 41
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68 APPENDIX B6--(Continued) Fabricators--Questionnaire Responses Organization Question Comment Pins (full size); proper bearing seat and anchor bolt placement; correct falsework (if used) placement; enforce submittal and approval of Grand Junction 6 an erection plan! Common sense. You must consider what type of shop assembly to use, which is based on how complicated the structure is; i.e., straight, Harris 6 curved, radius, skew, connections, and camber. High 6 Geometry control is a must. a. Substructure bearing seats adjusted for construction variations. b. Splice plates properly pinned. Industrial 6 c. Enough stabilizing members in place. d. Main member webs kept as vertical as possible. Lincoln 6 Good erection crews. One (if not the most important) issue is a properly detailed project. The detailing and the transfer of information through the shop and erection drawings is key. The next key issue for fabrication is the day-to-day control in the shop to ensure that the as-detailed bridge Stupp 6 becomes a reality. Also staying within the tolerance ranges for camber and straightness as provided by AWS, AASHTO, and specific state specifications. Lastly, and very important, is the communication of as-built condition or any variation from the details to the erector. Tampa 6 Field survey/concrete/bearing placement by others must be correct. Trinity 6 Alignment of connections before final tightening of bolts. We have found that if the erector does not properly pin the field connections with the proper amount of pins, the tolerance errors start to Universal 6 multiply throughout the remainder of the bridge, disallowing the proper camber and proper alignment of the webs (vertically). Vincennes 6 All pieces must be clearly match-marked. Keep all camber and sweep within tolerance. Unnamed 6 Keeping ends of girders aligned and webs vertical. Yes. Dennis Noernberg (501) 340-6314 The majority of the problems related to misalignment and poor final steel profiles are a result of the lack of use of drift pins. Many erectors are of the opinion that if a bolt will go in the hole I do not need pins. This is totally and grossly inaccurate. Pins in web splices AFCO 7 ensure correct profiles and pins in flange splices make a straight bridge straight and not dog-legged. Furthermore, pins in crossframe connections on curved bridges will ensure that torsional rotation of erected-only steel is properly resisted; otherwise, "roll-over" can occur and cause numerous other problems. Yes, we occasionally have problems in jobs built in more than one stage. When the Stage 1 deck has been poured, and the erector is trying to install the crossframes that connect a Stage 1 girder to a Stage 2 girder, he will pull the Stage 2 girder out of plumb trying to DeLong's 7 make the crossframe fit. We suggest waiting until after the Stage 2 deck is poured before installing the crossframes that attach Stage 1 to Stage 2. Egger 7 No Improper pier elevations during erection--insufficient crossframe installation during curved girder erection. Insufficient shoring on Fought 7 tightly curved bridges during concrete pour. Improper pinning of splice joints during erection.
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APPENDIX B6--(Continued) Fabricators--Questionnaire Responses Organization Question Comment Yes, have had problems on curved girder jobs where falsework could not be installed. Some of the girders had to be released from the Grand Junction 7 crossframes and lifted with a crane and reconnected. Also had problems with curved box girders where the internal lateral bracing members were too light and had to be replaced. Harris 7 Yes Most issues were related to incorrect information on designs, fabrication tolerances exceeded, or erectors not controlling geometry. Let me briefly explain with examples. Rehab job designs sometimes do not reflect the as-built condition. The outcome is self-explanatory. We erected several jobs for other fabricators that mislocated the point of curvature on a girder (details correct). This obviously threw the girder spacing off and created crossframe connection fit-up problems. Several times we supplied steel to contractors where their erector High 7 misaligned boxes and had trouble making splices. One example of this is where the job was staged. It involved box cross girders. The first phase was to place a short box and erect the longitudinal girders to it. It involved two lines of girders. The next phase was to erect the longer pier box and tie multiple lines (8) of longitudinal girders to it. The call from the field was that the splice in the boxes could not be made. As the fabricator, we saw an opportunity to build the box as one complete member and affix the splice plates to it and drill from solid after which the boxes were parted. It was foolproof. When we got to the field the contractor's erector misaligned the two boxes and the elevation on the pier was off. Geometry control, geometry control, geometry control--I cannot say it enough times. Another time the contractor's erector decided not to use the erection procedure supplied by the owner. He eliminated falsework. Unfortunately, each pier High 7A had cross boxes and since it was a continuous structure, tie plates were used across the box tops to tie in longitudinal girders on either side. As the fabricator, we had all members in full no-load assembly. The call from the field was that they could only see half a hole in the splice plates over the box. We had the solution and the contractor had his erector temporarily report to us on site. I was personally on site with one of our fabrication supervisors. Since the longitudinal girders tied into the web of the boxes, everything needed to be exact. The first thing we checked with a surveyor was the face-to-face dimension at the bearing locations on the boxes within the span they were working. The one side measured 5/32 in. different than the other. Bolt holes are oversized by 2/32 in. The box was moved 3/32 in. The next move was to pick the girders spanning High 7B the face to face of boxes within the span with multiple cranes and spreader beams to get the girders in a no-load configuration. The erector did this. Not all girders were placed in this span before we erected girders in the adjacent span. All holes were made with 7/8 in. bolts without a problem. Eliminating falseworks without a procedure to maintain geometry does not work. Geometry control, geometry control, geometry control--I cannot say it enough times. 69
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70 APPENDIX B6--(Continued) Fabricators--Questionnaire Responses Organization Question Comment Yes. On curved structures, which are subject to a steep grade and a tight curve, the problem of web verticality can become a heated issue. The top flange will resist coming to plumb. The contract design drawings will clearly define the amount of sweep and camber, but will Industrial 7 ignore this problem of twisting or torque that the web is subject to. This problem is magnified when there is a restricted erection area. The state must recognize that not every point of the web plate will be absolute plumb after erection and steel-load deflection. The designer must be able to recognize this potential problem and perhaps design using tub girders in lieu of a single girder. Lincoln 7 No The only problems recently have occurred on a couple of bridge-widening projects. In both cases there was no allowance made for the offset in elevation between the existing and new. I believe that in both cases there were assumptions made with regard to the dead-load deflection of the steel and decking to achieve proper alignment with the current deck elevation. In one case, the offset was minimal and Stupp 7 the deck had been removed from the existing. The slight offset was made up in the deck pour. In the second case there was no deck removal and thus the new steel was significantly higher than expected after erection. This made it impossible to tie the structures together permanently until the deck was poured. Both cases resulted in acceptable bridge projects, although the second case took considerably more time and effort. Planning for these conditions on widening projects is extremely important. Yes. Had more than one project that deflected more than was anticipated by designers (tub girders). One of the problems is that Tampa 7 fabricator has records for no-load camber position, but field has no check in the erected position so problem may not manifest itself until forms are in place. Then it is too late. Trinity 7 No comment. Universal 7 No Vincennes 7 No Unnamed 7 No AFCO 8 No DeLong's 8 No There is some experimentation being conducted that calls for drilling splice connection holes in girders by means of a computer-aided Egger 8 manufacturing (CAM) setup. This eliminates the need to position continuous girders for reaming. Grand Junction 8 No FHWA's TurnerFairbank Highway Research Center has full-scale research currently underway on curved I-girders. How they function High 8 and react could be tied into boxes. Understanding how curved and skewed bridges function and react is being addressed by the Associated Pennsylvania Constructors Subcommittee, Penn State University, and University of Pittsburgh for PennDOT. Industrial 8 No Lincoln 8 Yes. State of Kansas (John Jones).
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APPENDIX B6--(Continued) Fabricators--Questionnaire Responses Organization Question Comment There is an effort by the AASHTO/NSBA Collaboration Task Group on Erection in considering standards covering some of these areas Stupp 8 in which our company is participating. Also, there are task groups within the organization reviewing and updating standards for shop fabrication and quality control. Tampa 8 No, except differential deflection discussions at NSBA. Trinity 8 No comment. Universal 8 No Vincennes 8 No Unnamed 8 HDR has or is doing a study, I think. Research should be done by AASHTO so as to enable engineers to properly address problems of differential deflection at the design stage AFCO 9 and not ignore the problem. Even an experienced erector can experience makeup problems and end up with a structure that is not consistent with the intent of the designers unless this sort of problem is dealt with early in the process. DeLong's 9 No Grand Junction 9 None We need to consolidate current efforts and control the outcome with a better understanding. Pockets of activity usually do not lead to High 9 accepted standards. Industrial 9 Research the use of low-price stainless steel in bridge construction. Lincoln 9 Blank Stupp 9 We have no research recommendations at the moment. Trinity 9 No comment. Universal 9 No The alignment, deflection, and final position issues are discussed regularly at the NSBA/AASHTO collaboration meetings. Even with all DeLong's 10 of the educated, intelligent people participating in these discussions, we still have not reached a consensus. I believe these issues need to be looked at on a case-by-case basis. There is not a single, correct answer that will work for every structure. For complicated structures (other than straight and square), contractors and designers should require results (records) of QC/QA final Grand Junction 10 shop-assembly results. This ensures that the fabricator has assembled to match shop-assembly drawing requirements (within specified or agreed upon tolerances). Erectors tend to avoid using enough falsework or pins in connections. They think a bridge will hold its geometry and camber if they put a Harris 10 bolt in the hole. 71
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72 APPENDIX B6--(Continued) Fabricators--Questionnaire Responses Organization Question Comment Contractors, fabricators, erectors, designers, and owners need to be on the same page. Standards need to be established relative to determining if a girder does or does not need to be out of plumb at the time they are erected. This is based on girder stiffness and High 10 allowable stresses in girders and diaphragms. Crossframes will be detailed according to this determination. This is another standard to consider--detailing frames. Tolerances at time of erection and after decking need to be established also. We just cannot use the word "plumb," although it is the theoretical target. Industrial 10 The steel manufacturing industry and the steel fabrication/construction industry must start working together, like we have in the past. Lincoln 10 Blank What we have seen over the years is a better environment for communication between designers, engineers, fabricators, and erectors. We Stupp 10 all must continue in this effort to share ideas and experiences. We applaud this and other efforts within our industry to provide growth and understanding. Trinity 10 Have used two-girder assemblies with customer approval and had acceptable results. Oversized holes in crossframes. For box girders used as pier caps, keep the connection from the girder to the pier cap girder simple. We Vincennes 10 have seen these connections to be very difficult to ream while in assembly.
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APPENDIX B7 Erectors--Questionnaire Responses Erector Question Comment We answered "No." However, we have bid jobs where the owner provided a suggested erection scheme. We have seen this in both High 1 Pennsylvania and New Hampshire recently. The erectors that were awarded these jobs did alter the provided schemes shown on the plans to erect the job. I cannot recall working on any bridges where the owner provided an erection procedure. The contract documents often provide criteria that govern Neal 1 the sequence of some steps of the erection procedure. For example, one part of the erection must be done before another part is started to accommodate traffic during erection. These requirements have had little effect on the quality of the erected structure. Peterson 1 No Rollins 1 No We believe it has a positive effect because the designer needs to think through the scheme and associated forces to erect the project. We did see a project recently where the owner's designer stated on the bid package that the structure, after a pair of girders is erected and certain crossframes are High 2 bolted, can withstand a certain wind velocity and be stable. I am stating this because we, as the erector, had to prove the stability. Having found the statement to be true, we question the need for the verification. It seems like a waste of time and money for the owner to want things to be double calculated. I cannot recall working on any bridges where the owner provides an erection procedure. The contract documents often provide criteria that govern Neal 2 the sequence of some steps of the erection procedure. For example, one part of the erection must be done before another part is started to accommodate traffic during erection. These requirements have had little effect on the quality of the erected structure. The first thing we look at is do we need to support girders based on type of bridge, number of spans, and span length. The second item we check is to see if anything prohibits us from setting a falsework or positioning a crane. Holding cranes and rigging can function similar to falseworks many High 3 times. Span lengths control the need for either a falsework or multiple crane approach. Long spans usually require multiple falseworks to control geometry, especially in a multiple, continuous scenario. The location of falsework and sequence of erection are generally governed by (1) the overall site limitations and (2) the size and strength of the individual girder pieces. Examples of each are as follows: 1A. The clear channel requirements imposed by the Coast Guard may limit the placement of falsework. 1B. The location of streets and highways and railroads passing under the bridge will limit the location of falsework. 1C. The height of the bridge above the terrain will often limit the amount of falsework that can be economically used. Neal 3 2A. The spacing of the falsework is a function of the strength of the girders and their ability to cantilever from one falsework to the next. 2B. It is often desirable to start erection with a "haunch" girder balanced on a pier using a bracket attached to the pier and then land on a falsework with the next girder. 2C. For curved girders, additional falsework is often required to prevent the girder from rolling. The falsework is usually set to the cambered geometry with vertical adjustments provided by jacking devices. Deflections are calculated and the jacking range allows for landing on the adjacent pier or abutment. 73
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74 APPENDIX B7--(Continued) Erectors--Questionnaire Responses Erector Question Comment Locate falsework near splices and under stiffeners (add stiffeners as necessary if none are available), provide jacking capabilities in falsework, and Peterson 3 adjust as necessary to maintain proper elevations at the splices until all permanent connections are completed. Rollins 3 Engineering Yes. We have experienced problems with deflection, web vertically, and elevation--not alignment. We have had issues with certain highly skewed and a combination of curved/skewed bridges. A combination of high skew angle and a small curvature radius will be the most difficult. Owners want the girders plumb after the deck is poured and cured. One issue is plumb has no tolerance associated with it. For bridges with a high skew we High 4 detail the crossframes for final position. This means that the girder webs need to be forced out of plumb at the time of erection. The girder's rigidity or flex contributes to how easily this can be accomplished. For bridges with less skew or "right" bridges we detail the crossframes so that the webs are vertical under the steel dead load at the time of erection. We determine which way to proceed based on a calculation. No matter what the outcome, if the webs are leaning 1/16 in. from top to bottom after the deck is poured, the webs are not plumb. A tolerance needs to be defined, and the designer should verify that the tolerance is acceptable and frames, diaphragms, connections, and girders are High 4A not overstressed. We suggest 1/8 in. per foot of girder depth. There are generally few problems with alignment of straight girders during or after erection. With curved girders, where the girders are detailed to cambered geometry and the crossframes are detailed to final geometry, there will always be some distortion until all dead loads are finally applied. Neal 4 This leads to the curved girders being erected out of plumb in order to connect the crossframes. The use of undersized bolts will sometimes help in making the initial connections. Slotted connections do not seem to be the answer to this problem due to the loss of control of geometry. Peterson 4 No Rollins 4 No Yes. The answer again is dependent on span length. Our fabrication group does not want to see a flange size less than 12 x 3/4. "Flange cupping," High 5 when welding bearing stiffeners or other connection stiffeners, creates a flatness problem when smaller flanges are used. It is desirable that the flanges be sized so that each individual girder piece can laterally support itself when erected in a simple span or cantilever Neal 5 condition depending on the erection sequence. With long spans and small flanges, temporary lateral support trusses made of angles and wire rope are often required until adjacent girders are erected and permanent crossframes and lateral bracing are connected. Peterson 5 No Rollins 5 No
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APPENDIX B7--(Continued) Erectors--Questionnaire Responses Erector Question Comment Yes. Not only handling and erection concerns, but transportation concerns also come into play. Girder stability is essential when driving down the highway. First let me make a statement for the erectors if using beam clamps to erect the bridge. Lighter girder sections imply smaller beam clamps can be used. However, a 15-ton beam clamp can only grip the flange edge, if the flange is 12 in. wide. A 25-ton beam clamp requires a minimum flange size 15 x 1 to function. Therefore, we need to rig girders differently if flange sizes are in the 12 in. category to put them in place, and we do. Optimizing girder flanges requires a look at fabrication, transportation, and erection as a total picture. If asked independently, these three groups High 6 will supply different answers. LRFD design specifications take material designs to their theoretical strength limit states, thus saving on material costs. If the fabrication group can tolerate flange sizes 12 x 3/4 and design allows it, we need to verify if special handling is required during transit and erection. This means that special consideration should be given to how girders are picked and wheel spacings on how they get transported. Optimized materials in fabrication can be verified by designers if designers consider the unbraced length of the compression flanges, the width, and girder length. A good indicator (rule of thumb) is girder length (inches) divided by compression flange width (inches). Experience shows a value of 60 or less has stability during transport and erection. A value of 60 to 80 may be OK, but needs further stress High 6A calculations to verify, and values of more than 80 require temporary support (falsework or holding cranes) to offer stability. It is desirable that the flanges be sized so that each individual girder piece can laterally support itself when erected in a simple span or cantilever Neal 6 condition depending on the erection sequence. With long spans and small flanges, temporary lateral support trusses made of angles and wire rope are often required until adjacent girders are erected and permanent crossframes and lateral bracing are connected. Peterson 6 The length-to-width ratio between braced points should not exceed 60 to ensure stability while handling and erecting the members. Rollins 6 Yes. Stability of single girders. Yes. We encounter an issue when bidding certain states. The designs simply state that the general contractor is required to determine if lateral bracing is required for the bridge. The problem is that the bracing required for dead load and wind forces during erection may determine bracing High 7 sizes that do not suffice dead load of deck forces or sequence of pour. It is not a problem to make the bridge stable at any point, but the process is confusing during and after bid time. This is a real "stability issue." Bob Cisneros (717) 293-4086, Senior Project Engineer, serves on the APC Subcommittee on the Stability of Structural Steel and would be our contact for discussion. Each girder needs to be analyzed to determine the pick point(s) and whether temporary lateral support bracing is necessary. It is often possible to Neal 7 ground assemble two adjacent girders with the lateral bracing and crossframes and erect them as a unit so that temporary bracing is not required. Peterson 7 No Rollins 7 Yes. Stability of girders in handling and erection. 75
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76 APPENDIX B7--(Continued) Erectors--Questionnaire Responses Erector Question Comment Yes. If you are erecting two halves of a bridge with one half complete and open to traffic and later are required to connect the other half to it with High 8 diaphragms or crossframes, connect the one side with full-sized holes and field drill the other after the deck is in place. If you are rehabbing a job with deck removed from one half and live traffic on the other, leave the connections of the two halves in place. Peterson 8 No Rollins 8 No Girders need to be plumb when picking or after erected. Multiple cranes or shoring is an answer. We simply calculate the sum of moments in the High 9 transverse direction along the member length when we pick them to ensure they are level. Curved girders can be picked with a single crane using a correctly sized spreader beam or by using two cranes. The location of the pick points can Neal 9 be calculated so that the girder is picked straight without roll. Picking at two points usually eliminates any lateral stability problems as long as a line between the pick points runs through the center of gravity of the girder. Peterson 9 My experience with curved girders is limited. Rollins 9 Engineering Owners vary in their concept as to when to tighten bolts. Erecting a structure and having to go over it again to tighten certain members adds to High 10 cost. Girder stiffness and crossframe design come into play. We believe that long-span, straight bridges can have their splices tightened under no- load conditions. The key is to survey the elevations during erection before tightening anything. Most states require a minimum of 50% of the splice holes filled with pins and bolts at erection. The use of oversized drift pins ensures that the Neal 10 splice is properly aligned before final bolting. Peterson 10 None, so long as the final connections are correct. Rollins 10 Engineering Yes. Currently the Associated Pennsylvania Constructors Subcommittee on Stability of Structural Steel is addressing different related concepts. High 11 Penn State University and the University of Pittsburgh have also taken field data related to these subjects. Also, the FHWA TurnerFairbanks Highway Research Center has a full-scale research project currently investigating curved girder functions. Much research has already been done on curved girders. More needs to be done. As mentioned above, when the girders are detailed and fabricated Neal 11 to their cambered shapes and the crossframes and lateral bracing are detailed and fabricated to their geometric shapes, they will not fit when erected. Only after all dead load is applied will the bridge be properly aligned and plumb, which after all is the goal we all strive for. Peterson 11 No Rollins 11 No We need to consolidate current efforts and control the outcome with a better understanding. Pockets of activity usually do not lead to High 12 standardization.
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APPENDIX B7--(Continued) Erectors--Questionnaire Responses Erector Question Comment The key important issues associated with achieving a properly erected structure are accurate detailing and fabrication with adequate shop assembly Neal 12 to ensure the correct fit of the individual girders in the field. Peterson 12 No Rollins 12 No Geometric control. We like concentric, not oversized holes on all members to ensure alignment, spacing, and cross-slope geometry. Secondary High 13 members such as lateral bracing are an exception to this rule. Accurate shop fabrication, accurate location and elevation of supports, maintaining proper elevations at splices, and complete installation of Peterson 13 connections before releasing falsework. High 14 Contractors, fabricators, transporters, erectors, designers, and owners need to be on the same page. Take into consideration the position of the sun and temperature of the steel when checking the alignment of a structure. One line of girders may be Peterson 14 longer than the other because of shading of one by the other. 77
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78 APPENDIX B8 Fabricators--Respondents Fabricator City State Respondent Phone Number AFCO Steel Little Rock AR Dennis Noernberg 501-340-6314 DeLongs's Inc. Jefferson City MO Gary Wisch 573-635-6121 Egger Steel Company Sioux Falls SD Fred Lebichuk 605-357-2249 Fought & Company, Inc. Tigard OR Terry Weir 503-639-3141 Grand Junction Steel Grand Junction CO Jeff Bishop 970-242-4015 Harris Structural Steel Co. Piscataway NJ Richard McCallum 732-752-6070 High Steel Structures, Inc. Lancaster PA Robert Kase 717-390-4240 Industrial Steel Construction Hodgkins IL Robert Emerson 708-482-7500 Lincoln Steel Co. Lincoln NE Calvin Schrage 402-474-3030 Stupp Bridge Company St. Louis MO Dennis Nash 314-638-5000 Tampa Steel Erecting Company Tampa FL Cathy Klobuchar 813-677-7184 Trinity Industries, Inc. Houston TX Thomas Guzek 713-861-8181 Universal Structural, Inc. Vancouver WA Dave Williams 360-695-1261 Vincennes Steel Corp. Vincennes IN Kevin Day 812-882-4550 Unnamed Erectors and Contractors--Respondents Erector/Contractor City State Respondent Phone Number High Steel Structurers, Inc. Lancaster PA Robert Kase 717-390-4240 JS Rollins, Inc. Barlow KY Jay Rollins 270-334-3725 James Neal Trophy Club TX James Neal 817-430-3197 Peterson Beckner Industries McKinney TX Gilbert Bailey 972-562-6294