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Coastal Engineering: Theory and Practice
In the last few décades, Mechanically Stabilized Earth (MSE) walls are
well developed and widely recognized as gravity retaining walls. In a MSE
wall, an area or part of a zone is well reinforced and it delivers rétention
résistance. Wire mesh, welded bars, steel strips and bar mat are some of
the metallic reinforcing éléments used for reinforcement. Reinforcements
are also provided with polymeric reinforcement like geo-grids. Depending
on the site condition woven or non-woven geosynthetics are used to retain
the soil from the action of waves.
Fig. 8.18 Gravity walls.
8.7.2 Sheet pile walls
Sheet piles are usually a steel sheet that can be hammered into the
ground to support the earth pressures. Based on the site condition the
sheet piles are either driven by impact hammer or gently pushed into
the ground. In some cases, vibratory equipment is required for installing
sheet piles. In order to support a deeper excavations, tie-back anchors are
required to strengthen the sheet piles especially in the location of conjunction. The design of sheet pile will be based on numerous forces acting on sheet pile wall. Typically the active earth pressure on the back of
the wall and the passive earth pressure on the front of the wall are estimated to arrive at the section. The active pressure tends to move the wall
away from the backfill whereas, the passive earth pressure resists the wall
movement.
The main considérations for the design of sheet piles are structural safety
and stability, demands of aesthetics, availability of material, equipment and
expertise, constructability and ease of maintenance and also its durability.
Detailed design principles and considération can be found in Design of Sheet
Pile Walls manual (1994).
Coastal Engineering: Theory and Practice
In the last few décades, Mechanically Stabilized Earth (MSE) walls are
well developed and widely recognized as gravity retaining walls. In a MSE
wall, an area or part of a zone is well reinforced and it delivers rétention
résistance. Wire mesh, welded bars, steel strips and bar mat are some of
the metallic reinforcing éléments used for reinforcement. Reinforcements
are also provided with polymeric reinforcement like geo-grids. Depending
on the site condition woven or non-woven geosynthetics are used to retain
the soil from the action of waves.
Fig. 8.18 Gravity walls.
8.7.2 Sheet pile walls
Sheet piles are usually a steel sheet that can be hammered into the
ground to support the earth pressures. Based on the site condition the
sheet piles are either driven by impact hammer or gently pushed into
the ground. In some cases, vibratory equipment is required for installing
sheet piles. In order to support a deeper excavations, tie-back anchors are
required to strengthen the sheet piles especially in the location of conjunction. The design of sheet pile will be based on numerous forces acting on sheet pile wall. Typically the active earth pressure on the back of
the wall and the passive earth pressure on the front of the wall are estimated to arrive at the section. The active pressure tends to move the wall
away from the backfill whereas, the passive earth pressure resists the wall
movement.
The main considérations for the design of sheet piles are structural safety
and stability, demands of aesthetics, availability of material, equipment and
expertise, constructability and ease of maintenance and also its durability.
Detailed design principles and considération can be found in Design of Sheet
Pile Walls manual (1994).