Now that we have established the basics of the strength of driving sheet piles, we need to discuss the actual configuration and design of the product.
Driving sheet piles is an engineered product. Although it is light weight (it can be manually picked up and set in many circumstances) and can be installed relatively easily, it is in fact load bearing and like all driving sheet piles, subject to failure if not properly configured. Thus, all of the care that is necessary for the design and configuration of other materials and shapes of driving sheet piles, such as steel sheeting, should also be given when the design of Pultruded sheet pile walls is carried out. This includes but is not limited to the use of a licensed, experienced professional to carry out the design work.
As mentioned earlier, sheet pile walls are primarily designed to resist overturning and failure due to excessive bending stresses. Both of these are addressed in established methods used to compute the strength and overturning resistance of driving sheet piles.
There are two methods currently employed to analyze driving sheet piles for moments and deflections: "classical" methods and finite element methods. Classical methods involve computing the lateral earth pressures on both sides of a sheet pile wall and then configuring the depth of sheet penetration suitable to resist overturning. They also are used to compute bending moments and deflections in the sheeting. Although they can and traditionally have been implemented using "hand" solutions, a faster approach is to use computer software such as Pile Buck's sheet pile retaining wall software program SPW 911 v. 2.01 to perform the calculations. A significant advantage of using this software is that multiple cases can easily be analyzed.
Finite element methods are relatively new for the design of sheet pile walls. These model the soil and pile by dividing both into small elements; a stiffness matrix is then developed and solved to determine the forces, stresses and deflections of the various elements.
These methods should only be employed by those who are familiar with the use of finite element methods, not just sheet piling design.
This article comes from compositez edit released