1. Codes and Standards Future Work
Steel Concrete Composite (SC) Modular Construction for Safety-Related Nuclear Facilities
Codes and Standards
Future Work

2. Appendix N9 for AISC N690 N9A – General requirements
Materials, welding, etc.
N9B –Minimum requirements for SC sections
Reinforcement ratio and plate thickness
Concrete thickness
Plate slenderness
Tie system requirements
Shear connector spacing and size

3. Appendix N9 for AISC N690 SC specific failure modes
Prevented from governing design
N9B4 - Plate slenderness ratio to ensure yielding before local buckling (non-compactness)
N9B5 - Stud spacing and size to prevent interfacial shear failure from governing design strength
N9B6 - Tie system spacing and strength to prevent splitting failure of the composite section

4. Appendix N9 for N690 N9C - Analysis Recommendations
Stiffness as a function of concrete cracking
In-Plane shear stiffness (pre and post-cracking)
Flexural stiffness (pre and post- cracking)
Cracked stiffness for accident thermal loading combinations
Recommendations for finite element modeling
Calculation of Design Demands

5. Appendix N9 for N690 N9D – Design for axial tension demands
N9E – Design for axial compression demands
N9F – Design for flexural demands
N9G1 – Design for in-plane shear demands

6. Appendix N9 for N690 N9G2 – Design for out-of-plane shear Four cases:
(1) Tie system yielding or non-yielding
(2) Spacing less than thickness/2 or more
Account for size effects

7. Appendix N9 for N690 N9H – Design for combined forces
Interaction equation for two out-of-plane shears
Interaction equation for tie systems acting in interfacial shear and axial tension
Interaction surface for SC walls subjected to combined in-plane forces and out-of-plane moments

8. Appendix N9 for N690 N9J – Connection Design
Full strength connection design
Designed so that connection is stronger than weaker of connected walls
Ductile behavior ensured
Over strength connection design
Designed for 200% of seismic forces in combinations with other demands
Relies on overstrength to achieve HCLPF of 1.67 SSE

9. Appendix N9 for N690
Connections can be designed using connector elements that are widely used
Rebars, dowel bars
Welding, base plates
Shear studs, shear lugs etc.

10. Future Work Experimental evaluation of full-strength connections
SC wall-to-basemat connections
Experimental confirmation of joint shear strength
SC wall-to-wall joints
Experimental confirmation of SC wall to slab connections

11. SC Wall-to-Wall Joint
Experimental setups developed, specimens being designed
SC Wall-to-Wall Joint

12. SC Wall-to-Wall Joint Analysis
Nonlinear analysis benchmarked to experimental results, and used to conduct parametric studies

13. SC Wall-to-Basemat Connections
Full strength connection will develop strength of SC wall, no failure in connection elements
Setup designed and built, specimen being designed

14. SC Wall-to-Basemat Connection
Specimens being designed, and different options being evaluated analytically
Baseplate ”
O.C. Rebar
Lenton Rebar End Anchors

15. Future Research Needs
Effects of accident thermal loading on connection behavior and design
Effects of tornado and hurricane missile impact on SC walls (two-way shear strength)
Concepts, designs, and tests of SC floors.
Fire resistant design of SC floor slabs
Effects of penetrations and pipes on SC wall design strength

16. Future Research Needs
Benchmarked analytical approaches for evaluating behavior of complex SC designs
Evaluation of green options for concrete in SC walls
Effects of fabrication, erection, and construction related imperfections and tolerances on SC wall design
Inspection and monitoring plans
Damping ratios for SC systems