2013 Seismic Design Competition Clarifications
All clarification requests and answers will be posted on this page. Please read the official rules all clarifications before submitting a clarification request form.
Last updated: 14 November 2012
Q1.1: In the problem statement, "the building owner wants to make use of daylighting in the building for sustainability purposes". What is the angle of incidence of the sunlight? San Francisco State University
A: The angle of incidence of the sunlight is out of the scope for this competition. This statement is intended for teams to consider how the placement of exterior shear walls and frame members affects how light enters the building. [1.2]
Q1.2: Do the undergraduate participants have to be members of the school’s student chapter of EERI to compete in the Seismic Design Competition? Rice University
A: Yes, student participants must be members of the school’s student chapter of EERI to compete in the Seismic Design Competition. Student membership will be confirmed for each participant after the final registration deadline. Undergraduate participants may talk with their school’s EERI chapter about obtaining a student membership or visit EERI’s online student membership form: https://www.eeri.org/member-center/get-involved/become-a-member/
Q1.3: Do student members need to be national members of EERI as well as student chapter members or is only student chapter membership required? Brigham Young University
A: National student EERI members must be affiliated with a school's student chapter. A student is required to fulfill all national EERI student membership requirements. See Q1.2 for a link to become a national EERI student member. A student chapter may have school specific membership requirements which should also be fulfilled.
Q2.1: Will only the GM1 deflection count toward annual income? San Francisco State University
A: The accelerometer will be attached to the structural model for all three ground motions. Section 7.7a and 7.7b will be applied to each ground motion for each respective scenario. The results from Section 7.7 for each ground motion will be applied to the Annual Seismic Cost in Section 2.5. The Annual Seismic Cost will be applied to the Final Annual Seismic Cost, and the Final Annual Seismic Cost to the Final Building Income in Section 2.6 [2.5, 2.6, 7.7]
3. Competition Awards
Q3.1: What will be the basis of the architectural award? Will it be based on the concept as described in the presentation, the rendered images on the poster, on the structural model itself, or some combination of these? Oregon State University
A: The architectural award will be judged based on aesthetics, any information on the poster describing the basis or concept of the architectural design, and how the design meets the architectural demands, described in the problem statement, of the building owner.
4. Competition Schedule
5. Design Proposals
Q5.1: Are damping devices required to be included in the final model if approved in the design proposal? UCLA
A: No. However, if damping devices are included in the final structural model, they must be those pre-approved in the design proposal as is consistent with Sections 5 and 6.10. Otherwise, judges will not be checking if the structural model design submitted in the proposal matches the final design. Judges will also not be checking for violations of the rules in the proposal design. [5, 6.10]
Q5.2: It is stated in the rules that the 2 page maximum includes figures. However, there is no rule which explicitly states that figures must be provided. Would a detailed description of the design without figures or graphics be acceptable for the design proposal? Oregon State University
A: Yes. If damping systems are proposed, a figure is highly recommended in aiding the SDC committee's ability to determine if the damping system is legal.
6. Structural Model
Q6.1: Section 6.12 restrict the total weight of the model including the damping devices, roof plate and base plate to 4.85 lbs, but Section 2.4 states the Structural Model Weight does not include the weight of the base plate and roof plate. Which is correct? San Francisco State University
A: Both are correct. For scoring purposes, the weight of the base plate and roof plate will not count towards the Structural Model Weight. The total weight restriction is to ensure the capacity and stability of the shake table are not compromised. [2.4, 6.12]
Q6.2: Can shear walls be oriented in a direction other than perpendicular to the ground surface? San Francisco State University
A: Shear walls, as defined in Section 6.4, may be oriented in any direction. The cross section or plan view is defined as the plane normal to the grain of the balsa wood. The cross sectional plane is subject to the dimension restrictions in Section 6.4.a. All requirements in Section 6.4.b still apply. If the grain of the balsa wood of a shear wall is parallel with the ground surface, it is not required to span at least one floor. [6.4]
Q6.3: Can we use epoxy to glue base plate to members? San Francisco State University
A: Yes. [6.5a]
Q6.4: Are there restrictions on the orientation of the floor beams? San Francisco State University
A: The orientation of the beams is not restricted. However, floor beams must meet all requirements in Section 6.7b to be counted as rentable floor area. [6.7b]
Q6.5: Does Section 6.2.a require every 10th floor or only the 10th floor to be 4 inches? San Francisco State University
A: Only the 10th floor is required to be 4 inches. [6.2.a]
Q6.6: Is there a penalty per 1/8" deviation per floor in Section 6.4.a? San Francisco State University
Q6.7: Can shear wall to shear wall connections in Section 6.4.b be explained further? San Francisco State University
A: In plan view, the cross section can be rectangular or trapezoidal shaped. The long sides are two parallel sides of the rectangle or trapezoid that each have a length between 1" and 2 1/2" as defined in section 6.4.a. The perpendicular distance between the two long sides cannot exceed 1/8" as defined in section 6.4.a. The two other sides of the rectangle or trapezoid not defined as long sides are defined as short sides. In plan view, contact between two different shear walls may only occur between the long side of one shear wall and the short side of another shear wall. Also note that shear walls in contact must be glued. [6.4.a, 6.4.b, 6.5.a]
Q6.8: How will judges determine if a 2 1/2" diameter disc can pass through a floor? San Francisco State University
A: Teams will be asked to submit calculations for the area of each floor in the structural model. Floor area within the perimeter beams that intentionally allows a 2 1/2" diameter disc to pass through the plane defined by the perimeter and interior beams will be noted in the calculations with a simple sketch identifying the location of the floor area not counted as rentable floor area. Judges will inspect all floor areas before the competition with a ruler or other measuring device. [6.7.b]
Q6.9: Can the structural model roof plate be affixed to the structural model with glue? San Francisco State University
A: Yes, using glue to affix the structural model roof plate to the structural model is strongly encouraged.
Q6.10: What are the dimensions of the C-clamps used to attach the accelerometer to the roof plate? San Francisco State University
A: The maximum jaw opening is 1 inch and the throat is 1 inch.
Q6.11: A 2"x2" square hole will not allow a 2 1/2" diameter disc to pass through, but a disc could pass through if oriented in a vertical direction. Which orientation of the disc will be used in the requirement in Section 6.7.b? UCLA
A: The circular plane of the disc will be parallel with the plane of the floor defined by the perimeter beams. The intent of the rule is to mimic realistic clear-span distances between beams so a floor slab could be placed on the beams. However, for this competition, no balsa wood flooring will be required as it will increase the weight of the structural model. [6.7.b]
Q6.12: Is the 2 1/2" diameter disc requirement for the entire floor area? UCLA
A: Only the rentable floor area will be subjected to not allowing a 2 1/2" diameter disc to pass through the floor beams. If within the perimeter beams of the floor area, an area allows a 2 1/2" diameter disc to pass through the perimeter and/or interior beams, that area will not count towards rentable floor area when scoring in Section 2.3. Also note, to count as rentable floor area, the tops of the interior and exterior beams should be in the same plane. [2.3, 6.7.b]
Q6.13: Is there a limit to the length of a glued joint? UCLA
A: The dimensional requirements for structural frame member joints are in Section 6.5.b. See Figure A-5 in the Appendix for a diagram. Shear wall to shear wall connections may only have glue at the surfaces in contact. [6.5.b, Appendix A-5]
Q6.14: If glue is generously applied to a structural frame member, would the building finish not be considered acceptable? UCLA
A: The dimensional requirements for structural frame member connection joints are in Section 6.5.b. See Figure A-5 in the Appendix for a diagram. A penalty will be assessed if the dimensions of the glued joint are greater than the allowable dimensions in Section 6.5.b. If the judges deem the team is trying to gain a competitive advantage by deliberately applying glue to a structural frame member or shear wall beyond the connection regions to gain strength in that member, then the team will be disqualified as per Section 6.11. [6.5.b, 6.11, Appendix A-5].
Q6.15: What is the minimum clear distance between two parallel members? University of Notre Dame
A: No minimum clear distance is specified. However, shear walls in contact must be glued and are subject to Section 6.4.b and applicable clarifications. All structural frame member glued joint dimensions are subject to Section 6.5.b. The cross section for a structural frame member is defined as the plane perpendicular to the grain of the balsa wood. [6.4.b, 6.5.b]
Q6.16: How is the first story height measured? University of Notre Dame
A: The first story, or "Lobby", height is measured from the top of the base plate to the plane defined by the top of the perimeter beams supporting the floor labeled "2nd". [6.2.a, 6.7.b]
Q6.17: Is there a restriction on the type of plywood used for the structural model roof plate or structural model base plate? Can teams fabricate their own structural model base plate and roof plate out of balsa wood? Technical University of Cluj-Napoca
A: There is no restriction on the type of wood or how the structural model base plate and roof plate are fabricated. However, the SDC committee chairs highly recommend purchasing 3/8" nominal thickness plywood found at your local hardware store. If the judges deem the structural model base plate is too flexible or delaminates during shaking giving the team a competitive advantage by allowing the structural model base plate to dissipate energy by rocking, the structural model will be scored using Section 7.7.b and be assumed to have maximum equipment and structural damage for that ground motion and all subsequent ground motions as long as Section 7.7.a does not control. If the judges deem the structural model base plate is damaged to the point where the structural model base plate is not firmly attached to the shake table or the stability of the structural model is compromised, Section 7.7.a will be used for scoring. [6.8, 6.9, 7.7.a, 7.7.b]
Q6.18: Section 6.7.b states the perimeter beams at each floor must be continuous. Are the perimeter beams considered continuous if one perimeter beam is connected to the long side of a shear wall and another perimeter beam is connected to the other long side of that shear wall? Brigham Young University
A: Perimeter beams may be interrupted by vertical members or shear walls as long as another perimeter beam is connected to the vertical element. The perimeter beams connected to the vertical member or shear wall must be at the same elevation to meet requirements in Section 6.7.b. [6.7.b]
Q6.19: Can a level be partitioned into both rentable and non-rentable floor area within the building envelope? University of Notre Dame
A: Yes. Each floor level is defined by the flat and level continuous perimeter beams. If an area, within the perimeter beams, does not meet all requirements in Section 6.7.b, that specific area within the perimeter beams will not count towards rentable floor area. [6.7.b]
Q6.20: Can a floor level count as a floor in the building if it doesn't have rentable space? University of Notre Dame
A: A set of perimeter beams that are flat, level, and continuous define a floor level. The dimensions of the floor level encompassed by the perimeter beams are restricted to the dimensions in Section 6.2.a. Rentable floor space is not required for each floor level. If a floor level does not have a set of perimeter beams that are flat, level, and continuous, that floor level will be an unusable floor level and not count towards the floor levels in Section 6.2.b. The height between the two floor levels closest to the unusable floor level will be used to assess, if applicable, a floor height dimensional penalty defined in Section 6.2.a. If a floor level does have a set of perimeter beams that are flat, level, and continuous and the area within the perimeter beams does not meet the floor plan dimensional requirements in Section 6.2.a, a dimensional penalty will be assessed as defined in Section 6.2.a. [6.2.a, 6.2.b, 6.7.b].
Q6.21: Would a spring system located at the base plate designed to fail under different seismic loads be considered a damping system? University of colorado Boulder
A: The criteria used by the judges to determine if a damping system is legal: If the damping system is removed, the balsa wood structure, with all dead load weights attached, should be stable and firmly fixed to the base plate, and the sole purpose of the pre-approved damping systems is to dissipate energy. Base or floor isolation of any kind is prohibited. Damping devices may be attached to the base plate but do not count as a structural member when determining a foundation failure in Section 7.7.a. If the judges deem the spring system meets these requirements in the proposal submission, then the nonlinear springs may be used for hysteretic damping. [6.7.a, 6.10, 7.7.a]
Q6.22: Are we allowed to have bracing on the 10th floor and the core? University of Southern California
A: There is no restriction on the location of bracing. However, the location of bracing may affect requirements for rentable floor area in Section 6.7.b. [6.7.b]
Q6.23: Would it be acceptable for architectural purposes to include a facade/faux spire/finial/dome etc. atop the building in the renderings and descriptions on the poster that would exceed this height so long as it was not included in the structural model and was not included in calculating rentable floor area? Oregon State University
A: This would be acceptable.
Q6.24: Is the laser cutting of an entire floor(s) permitted if all structural frame members will meet the requirements stated in Section 6.3? Cal Poly San Luis Obispo
A: Yes, laser cutting is permitted. However, note that in Q6.2 that if shear walls are used in the laser cut section, the shear wall cross section dimensions, in Section 6.4, are measured normal to grain of the wood. [6.3, 6.4]
Q6.25: Do we still need to include the fastening holes in the base and roof plate on all sides for bolts, or are we depending only on the C-clamps to keep the tower and accelerometer in place? University of Nebraska Lincoln
A: Only C-clamps will be available to secure the base plate to the shake table and accelerometer to the roof plate. The only hole required in the base plate is to indicate the North direction. This hole in the base plate is explained in Section 6.8.c.
Q6.26: The rules state that the "total weight of the structural model, including the base and roof plates and any damping devices, should not exceed 4.85 lbs." How much should the structural model and base weigh on their own? Cal Poly Pomona
A: The total weight, including the structural model, base plate, roof plate, and if applicable, damping devices, is limited to 4.85 lb as a limit for safe operation of the shake table. There is no requirement on each specific component's percentage of the total weight.
7. Strong Ground Motion Testing
8. Score Sheets