الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Cellular quay walls are one of the high-end options for constructing quay walls Sheet pile cellular structures are used in a variety of ways, when an excavation is in a large area overlain by water, such as a river or lake; cellular cofferdams are widely used to fonn a water barrier, thus providing a dry work area. Cellular structures are eco¬nomical for this type of construction since stability is achieved relatively inexpensively by using the soil cell fill for mass. Ring tensile stresses are used in the interlocking steel sheet piling to affect a soil container. The same sheet piling may be pulled and reused wiess it has been damaged from driving into boulders or dense soil deposits.
Cellular quay walls are also used for retaining walls; fixed crest dams and weirs; lock. guide, guard, and approach walls; and substructures for concrete gravity superstructures. Each of these structures can be built in the wet, thus eliminating the need for dewatering. When used as substructures, the cells can be relied upon to support moderate loads from concrete superstructures. Varying designs have been used to support the concrete loads, either on the fill or on the piling. When danger of rupture from large impact exists, the cells should be strengthened to be able to accommodate
higher loads.
In some situation, the cellular quay walls are required to carry more loads than
intended in its original design as a result of harbor and traffic growth, which requires strengthening of the existing walls to be able to accommodate higher loads. Cellular quay walls can be easily rehabilitated due to their advantage of being easily constructed and improved in performance in a short period of time.
This study outlines four methods for retrofitting the cellular quay walls to increase its carrying capacity and decrease the stresses in its skin assuming that the overall stability of the wall is not compromised.
The first method; installing sheet pile segments to the cellular internal walls to
relief the stresses,
In the second method; installing internal cells with Y:z diameter of the basic
model not connected to the original skin and extend up to the original length
In the third method; installing internal cells with 31. diameter of the basic model also not connected to the original skin and extend up to the original length.
In the fourth method; piles are installed in different patterns to relief the stresses
on the cell skin.
Each of the four proposed methods is studied under four different assumed
1000ing conditions which are gravity, pressure, tension and crane loads.
Analysis of the original cellular quay wall and the proposed methods for nIrOfitting are performed utilizing the three dimensional finite elements method using the commercial software package Ansys 11.0. The model represents the soil as elastic 3D 8-nodes bricks, and the sheet pile as 4-node shell elements with elastic- perfectly plistic behavior of its material. Concrete segment such as capping beam and piles are modeled using 8-nodes elastic brick elements.
Results were analyzed using Excell 2007 and the effect of each method on stress ’,~ Jlduction as regards (ax ,ay .az ) and( a_on) Von Mises were studied. All values were
further compared to evaluate the effect of each retrofitting method on Yon Mises stress reduction.
This parametric study showed that the most effective technique for retrofitting
cellular quay walls is by adding sheet pile sections to the locations where strengthening is needed. Inner cells are not as effective as the first method. Piles in retrofitting cellular quay walls are the easiest to install, this technique gives moderate performance when compared to the other techniques.
The results obtained for the untreated cells are in good agreement with respect to the maximum stress given by the traditional analysis using Us Army corps recommendation.