MDSS Medium Diaphragm Spline Strap

1. Allowable loads have been increased for wind or seismic loading with no further increase allowed: reduce where other loads govern.
2. Applicable adjustments shall be applied following the ANSI/AWC NDS-15 or NDS-18.
3. Tabulated values are applicable for splines in the major and minor strength directions.
4. Screws: 1/4" x 3 1/2" SDS = model SDS25312; 1/4" x 6" SDS = model SDS25600; 0.22" x 4" SDWS = model SDWS22400DB; 0.22" x 6" SDWS = model SDWS22600DB
5. CLT panel minimum thickness is: 3-ply = 4.125"; 5-ply = 6.875"; 7-ply = 9.625"
6. The component of diaphragm deflection due to fastener slip at panel-to-panel joints is calculated as,
   δ_f = CLe_n
   where,
   
   • C=(1/P_L+1/P_w)/2
   • P_L = Length of individual CLT Panel (ft.)
   • P_w = Width of individual CLT Panel (ft.)
   • L = Overall length of diaphragm (ft.)
   • e_n = Force per fastener [lb]/Slip modulus [lb/in.]

(Reference — Applied Technology Council. 1981. Guidelines for the design of horizontal wood diaphragms. Redwood City, CA.)

For additional information on slip modulus, see:

1. American Wood Council. 2018. ANSI/AWC National Design Specification for Wood Construction, NDS®, Section 11.3.6. AWC, Leesburg, VA.
2. Zhan, J.J. 1991. Design equation for multiple-fastener wood connections. US Forest Service, Forest Products Laboratory, Madison, WI. 9 pp.0