OPTION 1:
3"x10" Glue-Laminated Beam framed structure
(actual beam measurement: 3 1/8" x 10 1/2").
OPTION 2:
Micro-Laminated Parallel Strand Beam Frame
(actual beam measurement: 3 1/2" x 9 1/2").
NOTE: MJS strongly recommends using a 4" x 10" Micro-Laminated Beam Frame (Micro - Laminated) instead of the Glue-Laminated Beam Frame (Horizontally Laminated), for the following reasons:
1. The 4" x 10" Micro-Laminated Beam
has higher engineering values. It has both a higher bending strength and a higher shear strength as can be seen by the following values:
OPTION 1: 3"x10" Glue-Laminated Beam
allowable design stresses:
A) bending strength = 2400 psi
B) shear strength = 165 psi
OPTION 2: 4" x 10" Micro-Laminated Parallel Strand Beam
allowable design stresses:
A) bending strength = 2900 psi (BETTER)
B) shear strength = 290 psi (BETTER)
Note: Higher values are better.
These figures show that the 4" x 10" Micro-Laminated Parallel Strand Beam
is a stronger and more rigid beam than the 3" x 10" Glue-Laminated Beam. This means you will have a much sturdier dock and less finger movement.
2.
The 4" X 10" Micro-Laminated Parallel Strand Beam
is actually thicker
than the 3" x 10" Glue- Laminated Beam
. The actual sizes are:
OPTION 1: 3" X 10" Glue-Laminated Beam
= 3 1/8" x 10 1/2"
OPTION 2: 4" X 10" Micro-Laminated Parallel Strand Beam
= 3 1/2" X 9 1/2" (BETTER)
3.
The 4" x 10" Micro-Laminated Beam
will not twist, shrink, or split
like the 3" x 10" Glue-Laminated Beam
. As can be seen by comparing the North Shore Marina's "Snack Bar Dock" and "Rental Docks" (framed with standard Glue-Lam Beams) with any of the "Village Docks" (framed with Micro-Lam Beams.) Dock fingers are to long for a standard glue lam they will twist. An under water jack support system was later required to be installed onto the Marina "Snack Bar Dock" when the fingers began to twist.
4.
The
4" x 10" Micro-Laminated Beam
is vertically Laminated with hundreds of 101 inch long plies
and the 3" x 10" Glue-Laminated Beam
is Horizontally Laminated with ~ 7 lams. (MORE LAMINATES ARE BETTER). The hundreds of micro lams are what gives the 4" x 10" Strand-Laminated Beam
more strength. Also, the horizontally laminated beam is not engineered to safeguard against the possibility of delamination, where the micro - laminated beam is backed up by though bolts and brackets spaced approximately every four feet after dock construction.
5.
The 4" x 10" Micro-Laminated Beam
Frame Dock is a lower profile dock. This helps assure that lower profile boats will not rub underneath the padding, thus adding protection for those boats. We switched to the lower profile frame shortly after we switched to16 inch thick floats from the older 12 inch thick floats. Our docks sit 3 inches higher from the water than the older docks while the top of the dock is at the same level as the older docks. A 10.5 inch frame combined with a 16 inch float results in a higher deck and padding level, thus a padding boat level problem.
6. Standard Glue-Lam Beams
have a higher shrinkage rate than a Micro-Lam Beam
. This can result in loosening joints and sheared and broken screws. Using the Micro-Lam Beams
lower the risk of these problems.
1. 16 inch thick EPS foam filled ACE Rotational Molded Float Drums**
**ACE ROTATIONAL MOLDED FLOAT DRUMS
:
These floats have a minimum .150 wall thickness and are rotational molded from virgin food grade materials with UV inhibitors assuring long life. The polyethylene shell with molded mounting slots, is unaffected by saltwater, oil, gasoline, and most chemicals. The floats are completely foam filled using a 1 to 1.5 density EPS. These floats meet Corps. of Engineers Regulation #36 CFR Part 327.