Beam-Z combined wall systems are usually made from either
a fully interlocking system or a welded system. Interlocking systems
have the advantage in that they do not rely on welding to
build the system. There have been others in the past, but the HZM
system from ArcelorMittal is currently the only fully interlocking
system available. It has 12 different beams and a couple dozen
sheet piles to choose from. Welded systems can use any of the
hundreds of available beams, such as W or HP, and sheet piles to
make the system.
Single, double and continuous beam systems with welded connections
Beam-Z systems are a good
choice for a combined wall
system when the driving is
too hard for sheet piles to be
installed to the required depth.
The beams can be driven into
weathered rock or glacial till to
achieve toe fixity. Sheet piles in
beam-Z systems are usually 60
to 80% of the length of the beam, and are only required to go to the
point of zero pressure in the total pressure diagram.
Another advantage of the beam-Z
system is the small footprint. Other
combined wall systems can be efficient
if the depth (beam depth or pipe
diameter) is not restricted, but for
a given depth, the beam-Z systems
have the best strength to weight ratio.
The calculation of the bending
properties of beam-Z systems is
straightforward. Although the sheet
pile does not sit on the neutral axis
of the system, the offset should not
be taken into account when calculating
the section properties.
ISystem = (IBeam + ISSP) / WSystem
SSystem = ISystem / DNA
ISystem: The moment of inertia of the system
IBeam: The moment of inertia of the beam and the connectors
ISSP: The moment of inertia of the pair of sheets
WSystem: Spacing of the king piles
SSystem: Section modulus of the system
DNA: Distance from neutral axis to extreme bending fiber of the beam
The section properties should be checked at different elevations
depending on the presence of intermediate sheet piles and connectors.
Connectors can also be added to the rear flanges of the beams
to increase the bending strength and decrease DNA by pushing the
neutral axis closer to the center of the beam.
STEEL SHEET PILING
It is important to remember that there are literally thousands of
different combinations of beams, connectors, sheet piles and steel
grades that can be put together to satisfy the needs of your project.
OPEN CELL sheet pile system
The history of domestic steel sheet piling dates back more than 100
years. With a new millennium came new piling-based engineering
challenges. Some 40 years ago, Peratrovich, Nottingham & Drage
(PND), a consulting firm specializing in marine engineering, was
determined to meet client demands for economical and easily
built waterfront structures with high strength capacity solutions
for heavy loading. PND responded with the OPEN CELL SHEET
PILE™ bulkhead concept.
OPEN CELL offers a flexible, flat sheet pile, tension membrane,
supported by soil contact with embedded tail anchor walls. This
concept creates an integral reinforced soil system. The result is a
structure that can withstand seismic loads, large settlements and
ability to form tall walls.
±0.00
Anchor
Earth
pressure
RH
AZ Zero earth pressure
level
HZ
More material at the flange increases
the moment of inertia, and reduces DNA,
which results in a higher section modulus
DNA DNA
ArcelorMittal HZ®-M Wall System
2020 Manual
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