Don Warrington

University of Tennessee at Chattanooga | Chatt · College of Engineering and Computer Science

Impact-vibration pile driving equipment has been an important part of vibratory pile driving equipment since the early years of development. In the 1960's the VNIIstroidormash institute in Moscow developed a series of impact-vibration hammers; however, the development of these hammers was stopped in favour of the diesel hammers. The emergence of th...

Virtually all treatments of power consumption and modelled performance for vibratory pile driving equipment assume a constant rotational speed of the eccentrics. In reality this is not possible due to the inertial effects of the eccentrics themselves and the necessity that, without inertia, the power output of the motor for the eccentrics must foll...

Hyperbolic soil modelling and strain softening have become better understood in recent years; however, their application to modelling load-deflection characteristics for the shaft of both bored and driven piles is in the early stages of development. This paper proposes a method that is based strictly on the strain-softening changes in shear modulus...

The application of semi-infinite pile theory to the behaviour of driven piles has been studied since Parola (1970). Most of the effort, however, has been concentrated on piles which do not require a cushion between the pile head and the pile driving accessory, such as steel piles. Concrete piles, on the other hand, are generally driven with this ad...

Warrington (1987) was a detailed analysis of the mechanics of impact pile driving using semi-infinite pile theory and pile impedance concepts. In this paper a review and expansion of the basic concepts set forth in this paper is performed. First, a review of the basic concepts and equations set forth in the original is first performed with revised...

Methods of estimating the capacity of driven piles from dynamic pile top data have been well established for many years. The STADYN program uses a finite element methodology that is different from those currently in use. In this paper this program is applied to a well documented pile scenario of concrete piles driven into predominantly cohesionless...

Abstract: The STADYN program was developed for the analysis of driven piles both during installation and in axial loading. Up until now the test cases used were in predominantly cohesive soils. In this paper, the expansion of the program's use into predominantly cohesionless stratigraphies has required consideration of two important factors. The fi...

Although it is widely understood that soils are non-linear materials, it is also common practice to treat them as elastic, elastic-plastic, or another combination of states that includes linear elasticity as part of their deformation. Assuming hyperbolic behavior, a common way of relating the two theories is the use of strain-softened hyperbolic sh...

This paper is a review and summary of the efforts made to develop a closed form solution of the wave equation as applied to driven piles. It discusses the early development of solutions and includes discussion of such topics as semi-infinite piles, solutions using both Fourier series and the method of images, and solutions specific to vibratory ham...

Methods of utilizing data collected from pile top force-time and velocity-time records during impact hammer driving have been used to estimate the static capacity of piles for many years. These methods have been successful but still suffer from questions regarding uniqueness and soil characterization. The method proposed in this paper uses a two-di...

Methods of utilizing data collected from pile top force-time and velocity-time records during impact hammer driving have been used to estimate the static capacity of piles for many years. These methods have been successful but still suffer from questions regarding uniqueness and soil characterization. The method proposed in this paper uses a two-di...

Mohr's Circle-or more generally the stress equilibrium in solids-is a well known method to analyze the stress state of a two-or three-dimensional solid. Most engineers are exposed to its derivation using ordinary algebra, especially as it relates to the determination of principal stresses and invariants for comparison with failure criteria. In this...

This dissertation discusses the development of an improved method for the static and dynamic analysis of driven piles for both forward and inverse solutions. Wave propagation in piles, which is the result of pile head (or toe) impact and the distributed mass and elasticity of the pile, was analysed in two ways: forward (the hammer is modelled and t...

He is not widely known outside of the fields he specialized in, but Adhémar Jean Claude Barré de Saint-Venant (1797-1886), usually known in the Anglophone world as simply Saint-Venant, was one of the premier scientists, engineers and mathematicians of the nineteenth century. Yet his religious and political stances made him unpopular in his native F...

The fixed end method used for the design of anchored sheet pile walls has been used with success since before World War II; however, computational limitations have forced designers to use simplifications such Hermann Blum developed. The original method called for the use of an “elastic line” solution, where the penetration of the sheet piling below...

This paper details the mathematical modelling of vibratory pile driving systems using a linear model with the objective of obtaining a closed form solution to estimate either the power requirement of the machine, the torque requirement of the motor driving the eccentrics, or both. It begins by reviewing the system model for the system without a sus...

This paper documents both the development of a closed form solution for the one-dimensional wave equation as it is applied to piles and its comparison to numerical solutions of the same problem. Wave mechanics have been used extensively in piles for many years but the solution of the wave equation has been almost exclusively a numerical one. The cl...

This thesis details the research into the one-dimensional wave equation as applied to piles used in the support of structures for civil works and driven using impact equipment. Since the 1950’s, numerical methods, both finite difference and finite element, have been used extensively for the analysis of piles during driving and are the most accepted...

This article is an overview of both the development and present status of impact-vibration hammer, with special emphasis on the situation in the Russian Federation. This last point is significant because the technology was originally developed there. The article is divided into three sections: 1) an overview of the basic principles of impact-vibrat...

This paper is a survey of analytical methods used to calculate the power consumption and transmission of vibratory hammers used in the installation of piles. The paper discusses the parameters, derivation, and comparative usefulness of various methods of computing the power consumption of these machines. The paper also discusses the importance of t...

This article is devoted to the results of studies and tests on impact-vibration hammers which make possible imparting to the pile either vibrations only or impacts along with these vibrations. It covers theoretical principles and basic designs of these hammers, which are equipped with an apparatus for varying the operating mode, and finally the res...

This paper is a survey of some of the methods and research efforts by which the drivability of piles is determined. First, a brief outline of the basic theory and the important parameters for driving by vibration are presented. Then, a wide variety of methods by which the drivability of piles is determined are presented and discussed, with special...

This report is an overview of vibratory and impact-vibration pile driving equipment. It discusses the history, types of equipment, types of piles driven, operational use and characteristics, vibratory mechanics and prediction methods of performance and pile resistance. NOTE: this is my most visited resource on Researchgate. My interest on this topi...

This paper describes a new wave equation analysis program called ZWAVE, which is a program specifically for external combustion hammers. The program is described in detail, the discussion dealing with topics concerning the program such as 1) the numerical method the program uses to integrate the wave equation, which is different from most other wav...

An analytical study was undertaken to develop a set of closed form equations to make preliminary estimates of the pile loads, stresses, dynamic resistance and other important parameters in the installation of offshore piling. Solutions were developed for cushioned and cushionless hammers alike, along with illustrations of sample results and compari...

A design analysis technique is presented for driven pile foundations. It is intended for an academic environment. Based on proven and publicly available code, a new set of routines was developed in PHP that enable the estimation of static pile capacity, the generation of axial load-deflection curves, the generation of p-y curves and their applicati...

This paper presents the application of the closed form solution for the damped wave equation to piles. The wave equation in numerical solution has been used for many years, generally without even a simple closed form counterpart. In this paper the closed form solution for the damped wave equation will first be stated and related to an actual pile d...