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In This Section
SSBC Rules and Clarifications
Student Steel Bridge Competition
2023 Official Student Steel Bridge Competition Rules
Download the Official Rules for the 2023 Student Steel Bridge Competition.
Release date: September 6, 2022
2023 Official Student Steel Bridge Competition Clarifications
Clarifications are based on the Student Steel Bridge Competition 2023 Official Rules. All clarifications have been reviewed and approved by the Rules Committee.
Download the clarifications index.
The submission form is closed. Any additional questions can be asked during the captains' meeting on Friday, June 2, during the national finals.
Click on each section below to read the posted clarifications.
SSBC Clarifications
1. Mission and Summary
There are no clarifications for Section 1 at this time.
2. Introduction
There are no clarifications for Section 2 at this time.
3. Problem Statement
Q3.1 Does the fact that Section 3 states that "a new bridge that pays tribute to the Sweetwater River Bridge's use of steel" influence aesthetics judging or the specific type of bridge that needs to be constructed? Josh Zavala, University of Illinois, Urbana-Champaign & Serena Moha, Oregon Institute of Technology
A. The problem statement and reference to the Sweetwater River Bridge provides context for the competition problem, but is not considered in aesthetics judging. Aesthetics judging is based on the bridge's appearance and the poster as described in Sub-Sections 6.2.1.1 and 6.2.1.2, respectively. Likewise, the configuration of the Sweetwater River Bridge has no influence on the type of bridge that teams design aside from the fact that they both are constructed of steel. [3, 6.2.1.1, 6.2.1.2, 9.2, 9.3]
4. Eligibility
Q4.1 May teams from outside North America compete in the Student Steel Bridge Competition? Michalis Koutsoftas, University of Cyprus
A. A team outside of North America may compete in a Regional Competition as a Guest Competitor at the discretion of the host school and ASCE if they meet one of the requirements outlined in Sub-Section 4.3.3. Guest Competitors are eligible to receive awards at the Regional Competition, but are not eligible to advance to the National Finals. [4.3.3, 4.3.3.1, 4.3.3.2, 4.3.3.3, 4.3.3.4, 4.3.4, 4.4.1]
Q4.2 Does the Student Symposium Paper Competition follow the same prompt as the Daniel W. Mead Prize Paper? Renata Mercado, Universidad Panemericana
A. The Student Symposium Paper Competition topic/prompt can vary from symposium to symposium and is selected by the student symposium host. Hosts often use the Daniel W. Mead Prize prompt, but they do not have to. A student chapter should contact their student symposium host about the topic for their student symposium if it was not clearly stated in the mailer. Note that the Daniel W. Mead Prize is a separate competition from the Student Symposium Paper Competition. If the Daniel W. Mead Prize prompt is used for the Student Symposium Paper Competition, it is a separate submission from the Daniel W. Mead Prize competition. [4.4.1.2]
5. Safety
There are no clarifications for Section 5 at this time.
6. Scoring
Q6.1 When will the scoring spreadsheet be posted and where can I find it? Rodrigo Zapata, New Mexico Institute of Mining and Technology
A. The scoring spreadsheet will be posted in early 2023. A link to it will be able to be found on the right side of the SSBC Rules and Clarifications page at aisc.org/ssbc. Prior to the posting of the spreadsheet, teams can use the construction cost and structural cost equations in Sub-Sections 6.2.5 and 6.2.6, respectively, to help evaluate their designs. [2, 6.1, 6.2.5, 6.2.6]
Q6.2 Do design plans for the bridge need to be submitted beforehand? Ellie Marsh, LeTourneau University
A. No. Design plans for the bridge are not required to be submitted either before or at the competition aside from what is required on the poster. [6.2.1.2]
Q6.3 What are the submission deadlines for the competition? Ellie Marsh, LeTourneau University
A. Teams are required to submit a Student Steel Bridge Competition – ASCE Student Chapter Participation Form in order to receive their competition stipend. The SSBC Intent and Eligibility Acknowledgement Form is part of that submission. While the deadline on these forms states October 30, 2022, the forms are still active so there is time for teams to submit if they have not done so already. These forms can be found on the ASCE website here. Teams should also check with their Regional Host School to see if any further submissions are required. Deadlines associated with requirements for an ASCE Student Chapter to be in good standing are February 1, 2023 with the requirements listed in Sub-Section 4.3.2.1. Teams will need to submit their cost estimations at their Regional Competition prior to the selection of the load case. Submissions for the optional video award are due May 1, 2023 and submissions for the optional Team Engagement Award are due April 3, 2023. [4.3.2.1, 6.2.8, 6.2.9, 6.4.1]
Q6.4 The poster requires a shear and moment diagram of the beam corresponding to the free body diagram, what does 'beam' refer to in this context? Charles Reedy, University of South Florida
A. Beam in this context refers to a single beam that represents one of the bridge stringers. The shear and moment diagram should be constructed for the full length of the stringer considering appropriate support and load locations based on one of the load cases specified in Sub-Sections 7.1(8) and 11.5. [6.2.1.2.1, 7.1, 11.5]
Q6.5 Is the name of the school used to identify the bridge required to be the full formal name of the school or can a typical abbreviated version of the school name be used? Will Carlson, University of Wisconsin-Platteville
A. An abbreviated version of the school name can be used provided that the school can be easily identified from the abbreviated version. Abbreviations that are typical of multiple schools are not permitted. A bridge that cannot be easily identified will receive a poor aesthetics rating. The name on the bridge should match exactly the name on the poster. [6.2.1.1.3, 6.2.1.2.1]
7. Schedule of Competition
There are no clarifications for Section 7 at this time.
8. Material and Component Specifications
Q8.1 If a connection contains multiple loose nuts and bolts, may some of the bolts and/or nuts be welded provided at least one pair of a loose bolt and loose nut is used in the connection? Jacob Dodge, University of Missouri Columbia
A. No. Bolts and nuts may not be welded to the bridge for any purpose. [8.2.2, 8.2.2.5]
Q8.2 How are the member dimension requirements checked? Basheer Allamy, Wayne State University
A. Each member is individually checked by placing it in the 3'6" x 6" x 4" box. [8.2.2, 8.2.2.2, 10.6.2]
Q8.3 Do the SSBC 2023 Rules supersede the Competitors’ Guide? Angel Lopez, University of Central Florida
A. Yes, the SSBC 2023 Rules and official clarifications take precedence over the Competitors’ Guide. A discrepancy in regards to welded nuts was updated in the Competitors Guide on September 20, 2022. Clarification 8.1 also provides further information on welded nuts. [8.2.2, 8.2.2.5]
Q8.4 May steel hex-flange nuts be used to make connections? Dylan Ruechel, University of Wisconsin-Platteville
A. No. Steel hex-flange nuts do not have an external shape of a hexagonal prism over their full length due to the flange [8.2.4.1]
Q8.5 May 4-sided nuts be used in a connection? Jacob Cipollini, University of Utah
A. No. All nuts must have the external shape of a hexagonal prism over their full length. [8.2.4.1]
Q8.6 May a nut that is strongly magnetic steel but contains a part that is not steel (i.e. non-metallic insert) be used in a connection? Lenny Aparicio, University of California, San Diego
A. No. All nuts must be made completely of strongly magnetic steel. A bridge that uses nuts that contain parts that are not strongly magnetic steel will not be eligible for awards, except for aesthetics and video. [8.1, 8.2.4.1]
Q8.7 Are zinc bolts permitted for use in bridge connections? Yelitza Perez, University of New Orleans
A. Zinc plated steel bolts are allowed to be used in bridge connections. However, a completely zinc bolt would violate the requirement that the bolts are strongly magnetic steel. Please note that zinc plated steel bolts will create hazardous fumes at welding temperatures that can cause symptoms resembling influenza. [8.1, 8.2.3.1, 8.2.3.2]
Q8.8 May a loose plate be used as a gusset plate to connect two members? Matthew Kihm, University of Arkansas, Fayetteville & Adelite Hategeka, University of Texas at San Antonio & Artur Santos, Temple University
A. Yes, the loose plate would be treated as a separate member during construction. It would need to meet the member requirements specified in Sub-Section 8.2. Any location where the plate contacts another member would require a connection that meets the requirements of Sub-Section 9.4. [8.2.2, 9.4, 10.1, 10.3.7, 10.3.11, 10.4, 10.6, 10.9]
Q8.9 How precise are the box measurements with respect to the specified dimensions of 3'-6" x 6" x 4"? Owen Feindel, Western New England University & Evan Blake, Western New England University
A. Precision varies since each conference will have its own box for checking compliance of the member dimension requirements. A member must fit into the box provided by the conference host without forcing it into the box. Since neither box nor members can be fabricated to perfectly exact dimensions, there is a significant probability that a member fabricated to N inches will not fit in a box built to N inches as a number of variables, including temperature, can influence the box and member dimensions. Members should be dimensioned to accommodate realistic tolerances. [8.2.2.2, 12.6]
Q8.10 Are the 3'-6" x 6" x 4" dimensions of the box the inside dimensions or outside dimension of the box? Hanwan Jiang, LeTourneau University
A. Inside dimensions. [8.2.2.2, 12.6]
Q8.11 May U-bolts be used as loose bolts in connections? Yelitza Cedeno, University of New Orleans
A. No. U-bolts are not considered bolts within the Student Steel Bridge Competition because they do not have a head. [8.2.3.1]
Q8.12 May nuts be used to decorate a bridge? Henry Ng Luo, Florida A&M University – Florida State University
A. No. [8.2.2.4, 8.2.2.5]
Q8.13 May a member contain parts that pivot? Kerry Stauffer, Bluefield State University
A. No. A member must retain its shape, dimensions and rigidity during time construction and load testing. See also Clarification Q10.1. [8.2.2.1]
Q8.14 May there be holes in members that are only for the purpose of attaching tools during construction? Henry Ng Luo, Florida A&M University – Florida State University
A. Yes, provided that a bolt is not required in that hole to satisfy the Connection Safety requirements in Sub-Section 9.4 and the tool is removed prior to the completion of construction. See also Clarification Q9.38. [8.2.2, 9.4.1, 9.4.2, 9.4.2.3, 9.4.3, 9.4.4, 9.5, 10.9]
Q8.15 May low-profile or jam nuts be used to make connections? Ben Almeida, University of Alaska Anchorage
A. Yes, provided that the nuts have the external shape of a hexagonal prism over their full length and do not have parts that flex or move. The nuts also shall be commercially available and not modified in any way. There is no restriction placed on the length of the nut, but the internal threads must extend for the full circumference over the full length of the nut. [8.2.4.1, 8.2.4.2]
9. Structural Specifications
Q9.1 What is the definition of mechanical connection and do interference fit connections fall into this category? T.J. Boylan, Florida Institute of Technology
A. A mechanical connection is defined as a connection where a part of a member is inserted into a part of another member and designed to resist movement without the presence of a loose bolt and loose nut or where another mechanical device other than a loose bolt or loose nut is used to secure two members together. An interference fit connection is a mechanical connection because of its reliance on friction to resist movement. An interference fit connection would also violate the restriction on tube-in-tube/sleeved connections. [9.4.2.5]
Q9.2 Does the stringer template provide dimension requirements for the size of the stringer or dimension requirements for the passageway? Eliseo Garcia Cruz, University of Nevada Reno
A. The stringer template provides dimension requirements for the tops of the stringers and for the passageway. The rabbets at the bottom of the stringer template (2 in. by 1 in. cut outs) define the dimensional requirements for the top of the stringers and the location requirement for the north and south stringers relative to each other. The tops of the stringers must be in constant contact with the top of the rabbets while the stringer template is slid along the length of bridge. The outer dimensions of the stringer template define the dimension requirements for the passageway such that the stringer template must not be obstructed when slid along the top of the stringers over the length of the bridge. [9.3.8, 9.3.8.1, 9.3.8.2, 9.3.9]
Q9.3 May faying surfaces be oriented such that they stack on top of one another? T.J. Boylan, Florida Institute of Technology
A. Yes. There is no restriction on the orientation of faying surfaces. [9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4]
Q9.4 May there be intentional gaps in a connection to avoid creating a faying surface? Thomas Hickey, New Jersey Institute of Technology
A. Yes. A connection is a location where two or more members come in contact with each other. The surfaces where members contact each other are considered faying surfaces. Surfaces in a connection with a gap between them will not be treated as faying surfaces unless the gap meets the requirements for an unintentional gap per Sub-Section 9.4.2.4. Gaps between surfaces must be accessible for inspection to ensure that a faying surface does not exist. [9.4.1, 9.4.2, 9.4.2.1, 9.5]
Q9.5 Is it possible for the SSBC Rules Committee to provide photo examples of allowable and illegal connections? Jacob Atkins, Oregon State University
A. A document containing drawings and pictures representing examples of allowable and illegal connections will be posted to aisc.org/ssbc by the end of the calendar year. Notification of its posting will be sent out through an SSBC email notification to those who have signed up to receive notifications. [9.4]
Q9.6 Does the stringer need to be assembled from individual members that fit into the box? Vitaliy Saykin, Geneva College
A. All components of the bridge must be assembled from individual members that fit into the box. Sections of the stringer may be part of members that serve other functions in the bridge. [8.2.2, 8.2.2.2, 9.2.1]
Q9.7 Can cross bracing fulfil the requirements of the stringers or do the stringers need to extend east to west along the length of the bridge? Vitaliy Saykin, Geneva College
A. The parts of members making up the stringers must provide a contiguous top surface that extends from inside the west end footing to inside the east end footing along the length of the bridge. Separate stringers must be located on the north and south side of the bridge such that the surface of the two stringers is always in contact with the tops of the two rabbets of the stringer template when the bridge is checked to ensure it provides a straight, clear decking support location as described in Sub-Section 9.3.8. The decking shall only be in contact with the tops of the stringer. [9.2.1, 9.2.2, 9.3.6, 9.3.7, 9.3.8, 9.3.8.1, 9.3.8.2, 9.3.9]
Q9.8 Are there specific connection requirements for the stringer? Vitaliy Saykin, Geneva College
A. The stringers are made up of either members by themselves or parts of a member and thus must conform to the connection requirements specified in Section 9.4. However at the tops of the stringers between adjacent members, there may be a horizontal separation not exceeding 1/4" and a change in elevation not exceeding 1/8". [9.3.9, 9.4]
Q9.9 If one half of a connection is made up of two angled flat surfaces that meet, how many faying surfaces are created provided that both of these surfaces are in contact with the adjacent half of the connection? Jordan Chung, California Polytechnic State University - Pomona
A. This connection configuration would be treated as two surfaces, one on each side of the corner or bend which is created where the two angled flat surfaces meet. Each angled flat surface would be treated as a separate faying surface. [9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5]
Q9.10 What is the definition of an inflection point in the context of a faying surface? Jordan Chung, California Polytechnic State University – Pomona
A. An inflection point is defined as a point along a curve at which a change in direction of curvature occurs. In regards to a faying surface, the restriction on inflection points means that the faying surface cannot contain a change in curvature, whether two-dimensional or three dimensional. [9.4.2.2]
Q9.11 Is the minimum clearance between the ground and the bridge 4" everywhere, even to the side of and between the footings? Preston Palmer, Utah State University
A. Yes. The clearance shall be no less than 4", measured from the surface of the ground or river, to any part of the bridge. The only exception is directly over the 1' by 1' footings where no clearance is required. [9.3.4]
Q9.12 If a circular hollow section is cut in half along its length such that it forms a semicircular cross-section and the top and bottom surfaces of this semicircular cross-section are in contact with another member, how many faying surfaces are created? Patrick Reed, Colorado School of Mines
A. There are two faying surfaces, one associated with the top and one associated with the bottom of the semicircular cross-section, similar to the way the top and bottom of a flat plate would be treated if it were sandwiched between two other plates from another member. [9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5]
Q9.13 Is there a limit on the number of degrees of freedom that a connection can resist without the presence of a bolt? Kyle, University of Hawaii at Manoa & Carl Furner, Drexel University
A. No, provided that the connection between members only contains at most two faying surfaces associated with each member being connected, these faying surfaces are penetrated by at least one loose bolt secured by a loose nut, and all other requirements of Sub-Sections 9.4 and 9.5 are met. Note that any surface in contact with a surface of another member, no matter how small, is considered a faying surface. [9.4, 9.4.1, 9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5, 9.4.3, 9.4.4, 9.5]
Q9.14 When does a set of nested convex or concave surfaces become a tube-in-tube or sleeved connection? Kyle, University of Hawaii at Manoa
A. A set of nested convex or concave surfaces are considered to be a tube-in-tube or sleeved connection when the outer surface completely surrounds the inner surface such that movements perpendicular to the faying surface can be resisted without the presence of a bolt (i.e. a contact surface that extends greater than 180 degrees around the circumference of the inner member). Tube-in-tube/sleeved connections are prohibited. [9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5]
Q9.15 May dowel pins be used in a connection? Ben Schleh, Milwaukee School of Engineering
A. No. The use of a dowel pin will create an interlocking connection which is prohibited. [9.4.2, 9.4.2.5]
Q9.16 How is a faying surface defined? Matthew Fortkamp, Harding University
A. A faying surface is defined as a surface of a member that is in contact with the surface of another member at a connection. There may be multiple faying surfaces at a connection depending on the connection's configuration. The maximum number of allowed faying surfaces at a connection is two associated with each member being connected. There are also a number of other clarifications that address questions regarding faying surfaces that may aid in understanding the definition of faying surface. [9.4.1, 9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5]
Q9.17 Does a connection where a part of a member is sandwiched between two parallel plates that are part of another member violate the interlocking restriction in Sub-Section 9.4.2.5 provided that only the surface of the two parallel plates touch the sandwiched member and the two created faying surfaces are penetrated by at least one loose bolt secured by a loose nut? Patrick Reed, Colorado School of Mines
A. No. This connection does not violate the requirements of Sub-Section 9.4.2.5 since the connection is not stable without the presence of the bolt. [9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5]
Q9.18 May the cross-section of one member contact the cross-section of an adjacent member without creating a faying surface? Kylie Kemppainen, University of Oklahoma
A. No. Any location where there is contact between two members requires a connection and creates a faying surface that must meet the requirements of Sub-Section 9.4.2 no matter how small the area of contact is. [9.4.1, 9.4.2]
Q9.19 May the allowable 1/8" change in elevation between the top of the stringers of adjacent members be a result of an offset over the entire cross-section of the connection? Kylie Kemppainen, University of Oklahoma & Rafa Avila, Georgia Institute of Technology
A. There is no restriction placed on what causes the 1/8" change in elevation between the tops of adjacent stringers. This allowance is provided because of the potential difficulties in fabricating a completely flat surface at a connection between members. [9.3.9]
Q9.20 What is required to be visible in order to inspect a faying surface and when will this inspection occur? Kylie Kemppainen, University of Oklahoma
A. The judges need to be able to see whether two surfaces are in contact, thereby creating a faying surface, and whether that surface is penetrated by a bolt. The judges do not need to be able to see the actual faying surface which is obscured due to the contact. Inspection of the faying surfaces will occur with the bridge in its as-built condition after the termination of timed construction and before the bridge is moved from the construction site or load tested. [9.1, 9.5]
Q9.21 What is the requirement for being able to inspect the nut, head of a bolt, and threaded end of a bolt? Ryan McLaughlin, University of Massachusetts
A. The nut, head of a bolt, and threaded end of the bolt need to be visible enough after the completion of timed construction that compliance with Sub-Section 9.4 can be confirmed. The judges do not need to be able to touch the bolt or the nut. [9.4.2.3, 9.4.3, 9.4.4, 9.5]
Q9.22 Is there a limit on how tight the gradual curve that makes up a faying surface is? Kevin Zhang, Tufts University
A. No, provided that the cross-section of the outer member does not surround the cross-section of the inner member enough that movement perpendicular to the faying surface can be resisted without the presence of a bolt. If the faying surface was an arc, the contact surface must not extend greater than 180 degrees along the circumference of the outer cross-section. [9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5]
Q9.23 How many faying surfaces are created by the inside of a channel section that is part of one member overlapping with a rectangular HSS that is part of another member such that all three sides of the channel are in contact with three walls of the HSS member? Kyle Jones, University of North Carolina, Charlotte
A. For this configuration, the overlapping channel section creates three separate faying surfaces for each member. Any connection where the parts of one member are in contact with three or more sides of a square or rectangular HSS member creates three or more faying surfaces at that connection. [9.4.1, 9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5]
Q9.24 May the bridge be designed with a truss system or other components that extend higher than the decking surface? Azan Siddique, Morgan State University & Matthew Kihm, University of Arkansas, Fayetteville
A. Yes, provided that all parts of the bridge at the end of timed construction fit within the bridge envelope shown in the Bridge Elevation Diagram (DWG 2) and the bridge provides a straight, clear decking support location and passageway allowing the stringer template to pass through unimpeded. [9.2.1, 9.3.2, 9.3.3, 9.3.5, 9.3.8, 9.3.8.1, 9.3.8.2]
Q9.25 May a tube-in-tube connection that utilizes a loose bolt and loose nut be used if a tube is inserted into another tube where less than four sides are in contact with the inside surface of the outer tube leaving a gap or gaps between the inner and outer tubes? Stefan Popescu, University of Southern California
A. No. Any type of connection that utilizes a loose bolt and loose nut where one tube is inserted into another tube violates the restriction on tube-in-tube/sleeved connections, no matter how many surfaces of the inner tube are in contact with inside surfaces of the outer tube. A smaller tube that is inserted into a larger tube, but does not contact any of the inside surfaces of the outer tube and is secured with a loose bolt violates the requirement that each connection must have at least one faying surface. [8.2.2.4, 9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5]
Q9.26 If the two members meet end to end such that the cross-section of one member is in contact with the cross-section of the other member, is this contact surface a faying surface? Josh Stewart, Harding University
A. Yes, the surface over which the two cross-sections are in contact is a faying surface no matter how thin the elements of the cross-section may be. The faying surface must be penetrated by at least one loose bolt secured by a loose nut. If it is not possible to penetrate the faying surface with a loose bolt, then the connection would be in violation of Sub-Section 9.4.2. See clarification 9.18 for further details. [9.4.2, 9.4.2.1, 9.4.2.3, 9.4.2.4, 9.4.2.5]
Q9.27 May there be a gap between the ends of members that contain the stringer provided that the connection ensures a continuous surface along the sides of the members across the gap? Josh Stewart, Harding University
A. The stringer portion of the member shall be contiguous (i.e. be touching), but there is no restriction on the location or the size of the surface over which the rest of the member touches besides the connection requirements provided in Sub-Section 9.4. The top of each stringer must provide a continuous surface with the exceptions that a horizontal separation not exceeding 1/4" (measured in the longitudinal direction of the bridge) and a change in elevation not exceeding 1/8" are allowed between adjacent members. [9.2.1, 9.3.8, 9.3.8.1, 9.3.8.2, 9.3.9]
Q9.28 How is the horizontal separation between adjacent members at the top of the stringers measured? Josh Stewart, Harding University & Avery Kugler, The Cooper Union
A. The horizontal separation between adjacent members at the top of the stringers is measured along the stringer's length at its top surface from the point where one member ends to the point where the next member begins. The measurement is taken after completion of construction. If the horizontal separation is uneven across the width of the top surface of the stringer, the minimum horizontal separation shall be measured. [9.3.9]
Q9.29 May a connection be oriented such that gravity holds the member in place provided that a bolt or bolts penetrate all faying surfaces at the completion of construction? Josh Stewart, Harding University
A. Yes, connections may be oriented such that the member is held in place by gravity provided that the presence of a bolt is necessary in order for the connection to function properly once construction is completed and all requirements of Sub-Sections 9.4 are met. Cam locks, dovetails, tube-in-tube/sleeved and other mechanical connections that are designed to resist movement without the presence of a bolt are prohibited. [9.4, 9.4.1, 9.4.2, 9.4.3, 9.4.4]
Q9.30 Is there a restriction on the thickness of a faying surface? Henry Ng Luo, Florida A&M University – Florida State University
A. Since a faying surface is a surface, it does not have a thickness associated with it. There is no restriction on the thickness of the parts of a member making up a connection provided that the member meets the member requirements specified in Sub-Section 8.2.2. [8.2.2.1, 8.2.2.2, 8.2.2.3, 8.2.2.4, 8.2.2.5, 8.2.2.6, 9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5]
Q9.31 What is the definition of separation as it pertains to Sub-Section 9.3.9? Avery Kugler, The Cooper Union
A. A separation is a horizontal gap between two members at the top surface of the stringer measured along the stringer's length from the point where one member ends to the point where the next member begins. [9.3.9]
Q9.32 What is the definition of split as it pertains to Sub-Section 9.3.9? Avery Kugler, The Cooper Union
A. A split is a gap or notch that spans the complete width of the top surface of the stringer within a member, rather than a separation between members. [9.3.9]
Q9.33 May the tops of the stringers only be in partial contact with the tops of the rabbets while the bridge is checked to ensure it provides a straight, clear decking support location with the Stringer Template? Avery Kugler, The Cooper Union & Han Wu, Cornell University
A. The tops of both stringers at every location along the full length of the stringers shall contact the tops of the two rabbets in the Stringer Template. There is no requirement in regards to how much of the tops of the stringers is in contact with the tops of the rabbets provided that there is contact and that the stringer template can be moved without obstruction. [9.3.8, 9.3.8.1, 9.3.8.2]
Q9.34 How is the 1/8" maximum allowable elevation change at the tops of a stringer measured? Avery Kugler, The Cooper Union
A. The elevation change at the top of the stringer between adjacent members is measured at the ends of the adjacent members. The elevation change is the distance from the highest point across the width of the top of the stringer of one member to the highest point across the width of the top of the stringer of the other member. In other words, the distance that one member would protrude above the top of the rabbet when it causes an obstruction as it tries to slide over the transition point between members. [9.3.9]
Q9.35 If the combination of two separate connections on a member prevents movement or rotation of the members relative to each other, does this configuration violate the restriction on interlocking connections? Anthony Li, University of California, San Diego
A. No. The restriction on mechanical/interlocking connections that are designed to resist movement without the presence of a bolt is for each individual connection and does not apply to combinations of separate connections. However, each individual connection must meet the requirements of Sub-Section 9.4. [9.4, 9.4.1, 9.4.2, 9.4.2.5]
Q9.36 Does the situation where one member is inserted into another member without a bolt connecting them violate the restriction on tube-in-tube/sleeved connections? Alex Fitchmun, California State University, Long Beach
A. If the outside surface of the inserted member is in contact with the inside surface of the member in which it is being inserted then a connection would be required. This connection would be considered a tube-in-tube/sleeved connection and would violate Sub-Section 9.4.2.5 and the requirement that all faying surfaces be penetrated by at least one loose bolt secured by a loose nut. If the two members do not touch where the one member is inserted into the other member, then no connection is required in this location and there is no violation of Sub-Section 9.4.2.5. However, the judges need to be able to inspect whether the two members are touching in accordance with Sub-Section 9.5. The design shall not intentionally try to circumvent the rules which will lead the bridge to be deemed ineligible for competition. [3, 9.4.1, 9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5, 9.5]
Q9.37 Do the rabbets in the stringer template represent the maximum dimensions for the stringer? Aymeric Destree, Syracuse University
A. The rabbet dimensions provide bounds on the stringers locations as well as representing the maximum allowable width of the top of the stringer. The width of the stringer may be smaller than 2 inches wide. The 1 inch height is associated with the passageway requirement and ensures that the loading grate only bears on the top of the stringers. The depth of the stringer can be greater than 1 inch provided that it allows the stringer template to slide unobstructed along the full length of the stringers. [9.2.1, 9.2.2, 9.2.3, 9.3.7, 9.3.8, 9.3.8.1, 9.3.8.2]
Q9.38 May there be a hole in the finished bridge that does not have a loose bolt through it? Connor Irwin, University at Buffalo
A. Yes, provided that a bolt is not required in that hole to satisfy the Connection Safety requirements in Sub-Section 9.4. If a bolt is required because of the Connection Safety requirements, the missing bolt is a violation of Sub-Section 9.4.2.3. [9.4.1, 9.4.2, 9.4.2.3, 9.4.3, 9.4.4, 9.5]
Q9.39 May the tops of the piers extend vertically past the tops of the stringers provided that the stringer template can pass inside the piers without obstruction as it is slid along the length of the stringers? Logan Glazier, Vanderbilt University
A. Yes [9.2.2, 9.3.2, 9.3.3, 9.3.7, 9.3.8, 9.3.8.1, 9.3.8.2]
Q9.40 May the top of the stringer change in elevation along its width or length provided that a part of the top of the stringer is always in contact with the top of the rabbets when the stringer template is slid along the length of the bridge? Han Wu, Cornell University
A. There is no restriction on changes in elevation along the width of the top of a stringer provided that the top of the stringer is always in contact with the top of the rabbets. Along the length of the bridge, the tops of the stringers must be no more than 2'-2" and no less than 1'-10" above the surface of the river, ground or footings. The tops of the stringers may change in elevation along their length, but there shall be no abrupt changes (i.e. localized jumps) in elevation or slope, except for the allowable 1/8" change in elevation between adjacent members that comprise a stringer. If the slope or change in elevation along the top of the stringers causes loading conditions that the judges deem to be excessive and unsafe, then the bridge will be withdrawn from competition. [5, 9.2.2, 9.2.3, 9.3.7, 9.3.8, 9.3.8.1, 9.3.8.2, 9.3.9]
Q9.41 If two members have a gap between them after the completion of construction, but end up touching during loading, will there be a penalty due to the lack of a bolt at that location? Noah Rodney, United States Military Academy
A. No. The Connection Safety requirements specified in Sub-Section 9.4 are checked by the judges after termination of timed construction and before the bridge is moved from the construction site or load tested. However, if teams attempt to gain an advantage by trying to circumvent the rules in the opinion of the judges or the judges determine that the bridge cannot be loaded safely, then the bridge may be deemed ineligible for awards, except aesthetics and video. [3, 5, 7.1, 7.2, 9.1, 9.4]
Q9.42 May there be parts of a member that help retain a nut in its place such that once the nut is dropped into its position, a bolt can be threaded into the nut and the bolt and nut can be tightened without the need for the nut to be constrained with a tool? Rich Teising, Vanderbilt University
A. Yes, provided that these parts of the member do not contact another member creating additional faying surfaces and provided that the nut and threaded end of the bolt are visible to be able to check compliance with Sub-Section 9.4 [9.4, 9.4.4, 9.5]
Q9.43 May the top surface of a single stringer be made up of two thin parallel surfaces (i.e. two thin rails)? Jonathan Clausen, University of Louisville
A. Yes, provided that the requirements Sub-Sections 9.3.8 and 9.3.9 are met. [9.3.7, 9.3.8, 9.3.8.1, 9.3.8.2, 9.3.9]
Q9.44 May multiple members be penetrated by a single loose bolt utilizing more than one loose nut to make a connection? Kushal Ankola, Kennesaw State University
A. More than two members may be connected by a single loose bolt. Multiple nuts also may be installed on a single loose bolt provided that all nuts are fully engaged by the threads of the matching loose bolt. Nuts may not be used to separate different plies of a connection if at least one and at most two faying surfaces associated with each member being connected are not present. The contact surface between a nut and a member is not considered a faying surface. [9.4.2, 9.4.2.3]
Q9.45 May a single, large gusset plate that is welded to one member be used to connect multiple members? Lauden Jones, Colorado State University
A. A single, large gusset plate that is welded to one member can be used to connect any number of additional members to the member with the gusset plate provided that the connection requirements of Sub-Section 9.4 are met. Once a plate is welded to a member, it becomes a part of that member. Each contact surface of one member that touches the surface of another member creates a faying surface associated with each of the members in contact. All faying surfaces must then be penetrated by at least one loose bolt secured by a loose nut. [8.2.2, 9.4, 9.4.1, 9.4.2, 9.4.2.1, 9.4.2.2, 9.4.2.3, 9.4.2.4, 9.4.2.5, 9.4.3, 9.4.4]
Q9.46 In a sandwich plate type connection (a plate that is part of one member is sandwiched between two plates that are part of another member) that is oriented vertically such that the top surface of the connection also serves as the top of the stringer, is there a separation along the top of the stringer at the ends of the members due to the fact that the ends of the single plate and double plates do not touch the adjacent member so as to avoid creating a faying surface at that location? William Carlson, University of Wisconsin - Platteville
A. Provided that all the requirements of Sub-Section 9.4 are met, there is no separation associated with this connection because there is a continuous surface making up the top of the stringer due to the overlap of the single and double plates in the connection. The width of the top of the stringer may vary over its length. [9.3.8, 9.3.8.1, 9.3.8.2, 9.4]
Q9.47 May there be a hole in the top of the stringer provided that the top of the stringer is in contact with the tops of the two rabbets in the stringer template at every location along the full length of the stringer? Saul Chaplin, University of California, San Diego
A. Yes, since the width of the top of the stringer may vary over its length. See also Clarification Q9.43 and Q9.46. [9.3.8, 9.3.8.1, 9.3.8.2, 9.3.9]
Q9.48 Are there any requirements regarding how tightly nuts must be installed on bolts at the end of timed construction? Lucas Mandujano, University of California, Irvine
A. No. Each individual nut must fully engage the threads of the matching bolt. However, the configuration of the connection must ensure that the faying surfaces remain in contact at the end of timed construction in order to be considered a valid connection. [9.4.2, 9.4.3, 9.4.4, 9.4.5]
Q9.49 May portions of the bridge extend beyond the vertical plane extending upward from the point of contact of the bridge within the footing provided that the bridge remains within the bridge envelope and construction zone? William Liffrig, United States Air Force Academy
A. Yes. However, the bridge must remain within the bridge envelope and thus the ends of the bridge shall not extend beyond the vertical planes that make up the construction zone boundary. [9.3.5]
Q9.50 May portions of members that serve different purposes, such as transverse bracing, also serve as part of the stringer? Ahmed Khamiss, Southern Methodist University
A. Yes. There is no restriction on what members make up the stringer provided that the top surface of the stringer is contiguous (i.e. touching) and the stringer extends from inside the west end footing to inside the east end footing on both sides of the bridge. Only the portions of a member that make contact with the top of the 2 in. wide rabbet of the stringer template when checking the requirements of Sub-Section 9.3.8 are considered part of the top surface of the stringer. See also Clarifications Q9.7 and Q9.27. [9.2.1, 9.3.6, 9.3.7, 9.3.8, 9.3.8.1, 9.3.8.2, 9.3.9]
10. Construction Regulations
Q10.1 During construction, may a connection between two members allow the members to pivot relative to each other prior to final tightening of the loose nut on the loose bolt? T.J. Boylan, Florida Institute of Technology
A. Yes. There are no restrictions placed on connections or relative movement of pieces making up the constructed portion of the bridge during construction provided that safe construction practices are maintained. Connection requirements specified in Section 9.4 of the SSBC Rules will only be checked upon completion of construction. [9.4, 10.1, 10.3]
Q10.2 May an assembly of more than one member connected together be removed from the constructed portion of the bridge during construction and transported to be connected to another constructed portion of the bridge? Michael Pook, Marquette University & Patrick Reed, Colorado School of Mines
A. No. The removed assembly is no longer considered a constructed portion once removed from the constructed portion of the bridge. Since it is an assembly of more than one member, it also is not considered a single member. A builder shall not support or touch, directly or with tools, more than one member that is not part of a constructed portion of the bridge. Construction will be stopped because it cannot depend on deliberately committing an accident and a penalty will be imposed for a member coming in contact with another member outside of the staging yard. [10.1.6, 10.3.7, 10.3.12, 10.4.3]
Q10.3 Are temporary supports that are not part of the fully constructed bridge and do not touch the ground allowed to support members? Ben Schleh, Milwaukee School of Engineering
A. Yes. Temporary supports that are attached to the bridge during construction such that they do not touch the ground can be used to support members. Since the temporary supports are not part of the final bridge, they are considered tools and they and the members they support would not be considered part of the constructed portion of the bridge. The members that are held by the temporary supports also must not be in contact with each other or a penalty of a 1/4 minute will be assessed. [10.1.6, 10.2.4, 10.3.7, 10.4.2, 10.4.3, 10.6.1, 10.9.1]
Q10.4 May temporary piers that touch the ground or river be used since they have been used in past competitions? Zach Knuckey, Mississippi State University
A. No. A temporary pier is considered a tool in the 2023 rules. Tools are not allowed to touch the river or ground outside of the staging yard. [3, 10.4.2]
Q10.5 During construction, may members of the bridge be held together by temporary pins during construction, so long as all the pins are removed prior to the completion of construction? Berit Klein, University of Minnesota
A. Yes. There are no restrictions placed on how members are connected during construction provided that safe construction practices are maintained. The temporary pins would be considered tools and must meet the requirements of a tool. Connection requirements specified in Sub-Section 9.4 of the SSBC Rules will only be checked upon completion of construction. [9.4, 10.1.4, 10.2.4, 10.3, 10.6.1, 10.6.2, 10.9.1]
Q10.6 May a barge or other temporary support that touches the river be used during construction of the bridge? Lauden Jones, Colorado State University
A. No. Construction techniques that require a temporary pier or barge within the confines of the river are not allowed. [3, 10.4.1. 10.4.2]
Q10.7 May a temporary support touch the ground within the footing? Paige, The College of New Jersey
A. No. Only a member or constructed portion of the bridge may touch the ground within a footing. [10.4, 10.4.2]
Q10.8 May a tool be used to support the weight of the bridge if the tool is held by a builder and is not in contact with the ground? Simon Mathiowetz, Marquette University
A. A builder or a tool held by a builder shall at no time support the entire weight of a constructed portion of the bridge. However, if the constructed portion is in contact with the ground within a footing, then a tool may be used to also support that constructed portion provided that the builder holding the tool is within the construction zone. [10.3, 10.3.7, 10.3.11, 10.3.12]
Q10.9 When is a member considered a part of the constructed portion of the bridge? Ayan Ali, University of Texas, Arlington
A. Once a member is in contact with a constructed portion of the bridge or is in contact with the ground within the footing, it is considered part of the constructed portion of the bridge. No bolts are required for a member to be considered a part of the constructed portion of the bridge during construction. [10.1.6, 10.3.10]
Q10.10 May the bridge, which supports its own weight through contact with the ground within one or more footings, be held in position during the construction process by a tool that spans the entire length of the bridge? Sean H, The College of New Jersey
A. Yes, but the tool or individual tools that are combined to form an assembled tool during construction must fit within a right rectangular prism of dimensions 3'6" x 6" x 4". A tool also may not be in contact with more than one member that is not part of a constructed portion of the bridge. Also see Clarification Q10.7 [10.2.4, 10.3.7]
Q10.11 May bolts be placed into holes in members outside of the construction zone? Connor Irwin, University at Buffalo
A. Yes. However, the bolt may not be used to connect one member to another member outside of the construction zone. [10.1.4, 10.3.7, 10.3.11]
Q10.12 Must a constructed portion of the bridge contain a member that is in contact with the ground within a footing? Sharod Nandi, University of California, Davis
A. Yes. [10.1.6, 10.3.10, 10.3.12]
Q10.13 May the bridge extend into the transportation zone during timed construction? Kieran Elrod, University of California, San Diego
A. Yes, provided that all parts of the bridge remain within the site boundaries during construction. However, a builder must be in the construction zone in order to touch (or touch with a tool) a constructed portion and shall not install a member, loose nut, or loose bolt on a constructed portion outside of the construction zone. At the end of timed construction, parts of the bridge shall not extend beyond the vertical planes that make up the construction zone boundary. [9.3.5, 10.1.2, 10.1.3, 10.3.11, 10.3.13]
Q10.14 May a constructed portion of any size be supported by a builder provided that one part of the constructed portion is in contact with the ground within a footing? Kieran Elrod, University of California, San Diego
A. Yes, if the constructed portion is in contact with the ground within a footing, then a builder may support that constructed portion provided that the builder is within the construction zone. [10.3, 10.3.7, 10.3.11, 10.3.12]
Q10.15 Does the team captain have to be a builder? Brandon LaChance, California State University, Chico
A. Yes. The person designated as the "captain" for the competition must be a builder. This person will serve as the "captain" throughout the competition. [10.1.1]
11. Load Test Instructions
Q11.1 Are hiking boots that are constructed of canvas, suede leather and plastic considered acceptable leather construction boots for load testing? Judge
A. Yes, provided that the judges feel that boots will provide protection from puncture in the event of a grate or an angle used for loading being dropped on them. [11.2.1.3]
Q11.2 What is the specified north to south dimension for the decking? Luan Biberaj, Manhattan College
A. There are no set dimensions for the decking, but the decking must fit within the passageway defined by the stringer template meaning that the north to south span of the decking must be less than 3'-7". Typically, W-19-4 grating is used for the decking, which has dimensions of approximately 3'6" (north-south) x 3'-0" (east-west) x 1" (thickness). [9.3.8, 9.3.8.1, 11.5.1.1, 12.2]
Q11.3 What are the dimensions of the loading weights placed on the bridge during vertical loading? Lucas Mandujano, University of California, Irvine
A. There are no set dimensions for the loading weights used during lateral and vertical loading. The load used is supplied by the host school and should be supplied in pieces of uniform size and weight that can be handled safely. The recommended load consists of 25-pound lengths of 4"x4"X3/8" or 5"x5"x5/16" steel angles placed on the decking perpendicular to the length of the bridge. The load used should consist of members small enough that they does not overhang the decking surface. [11.4.1, 11.5.2, 11.5.3, 12.4]
Q11.4 During loading, may the bridge deflect such that there is less than a 4" clearance between the bridge and the ground if before loading the bridge allowed for a 4" clearance at every location except over the footings? Dylan Ruechel, University of Wisconsin-Platteville
A. Yes. The 4" vertical clearance requirement will only be checked with the bridge in its as-built condition after termination of timed construction and before the bridge is moved from the construction site or load tested. However, during vertical load testing loading will be stopped if any measured deflection exceeds 3" downward. [9.1, 9.3.4, 11.5.2]
Q11.5 Are the lateral and vertical load applied at the same time during load testing? Eduardo Medina, Florida International University
A. No. The lateral load test and the vertical load test are separate tests. The lateral load test is conducted first and then the vertical load test is conducted. [11.4, 11.5]
Q11.6 Why are deflections (D1 and D2) and sway being continuously monitored during the vertical load test if the deflection measurements are only recorded after all load has been placed on the bridge? Eduardo Medina, Florida International University
A. The deflections and sway are continuously monitored during construction for safety reasons (i.e. to identify if a bridge is becoming unstable or if collapse is imminent). As such, if sway exceeds 1 inch or any measured deflection exceeds 3 inches downward during loading, vertical loading will be stopped and the bridge is not approved for further load testing and will not be eligible for awards, except aesthetics and video. The recorded deflection measurement occurs once all load has been applied to the bridge in order to evaluate the bridge's stiffness relative to other bridges and to calculate the structural cost. [6.2.4, 6.2.6, 11.5.1.1, 11.5.1.3, 11.5.2, 11.5.3]
12. Equipment Provided by Host
There are no clarifications for Section 12 at this time.
13. Interpretation of Rules
There are no clarifications for Section 13 at this time.
14. Judging
There are no clarifications for Section 14 at this time.
15. Appeals
There are no clarifications for Section 15 at this time.
APPENDIX
- Site Plan Diagram
- Bridge Elevation Diagram
- Lateral Load Test Plan Diagram
- Vertical Load Test Plan and Elevation Diagram
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