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By R. Stenne

This paper deals with a complementary soil investigation which being part of the contract helped understand the behavior of a softened clay and adjusted the design of a retaining structure accordingly. The investigated softened clay proved to have lost its original strength but had maintained some characteristics of its stress history and in particular high horizontal stress. Pressuremeter tests and flat dilatometer tests were of interest to estimate the at rest earth pressure. A design consisting of a T-shaped slurry wall in conjunction with transverse walls was the most effective solution to cope with high active pressures and low passive pressures.

Jan 1, 2000

By Harpal Parmar

This paper evaluates dynamic methods of pile capacity prediction by comparing their results to static load test results. Dynamic and static pile load test data were assembled from four southeastern states of the U.S. End-of-drive and restrike capacities were evaluated using the Pile Driving Analyzer (PDA) and by wave equation (WEAP) analyses. These were compared to static (Davisson criterion) loads. The best comparison was obtained for restrike PDA results; restrike wave equation analyses values also compared well. The end-of-drive results for both methods-showed relatively poor comparisons. The PDA was recognized as an important tool to measure energy transferred to the pile; this transferred energy was recognized as an uncertainty when conducting wave equation analyses. A statistical analysis showed restrike capacity results to be associated with higher precision and accuracy as compared to end-of-drive methods. The authors believe that restrike dynamic testing is essential to establish long term static soil strength and that it will lead to accurate and cost-effective design of piles.

Jan 1, 1996

By Mark Zablocki, Dakarai McCoy

Ground vibrations are an unavoidable effect of driving piles and may pose a risk to nearby infrastructure and the comfort of adjacent occupants. Driven-pile-induced ground vibrations are known to vary widely based on ground conditions, pile material, and installation means and methods. A monitoring sensor to record ground vibrations during pile driving is necessary for understanding potential impacts to sensitive infrastructure and should be considered when implementing a monitoring program anticipating ground vibrations. The implementation of a vibration monitoring program historically relies on experiential-based decision-making, which may result in the costly vibration monitoring of low-risk infrastructure. Prior understanding of anticipated ground vibrations is necessary to create an appropriate monitoring program. A framework is proposed for organizing data from past monitoring programs and quantifying the anticipated risk of driven-pile-induced vibrations. An example of risk quantification from data imported to ]a cloud database is presented by comparing driven steel H-pile and prestressed precast concrete vibration monitoring measured and collected by Haley & Aldrich between 2010 and 2020. The methods presented within the example can be applied to quantify a first order approximation of risk for ground vibrations at proposed driven pile sites based on the measured performance of previous sites with similar ground characteristics and pile installation methods. The presented novel data managements tools allow for a quick aggregation of vibration data with similar site conditions.

Sep 8, 2021

By Erwin Stötzer, Renato Fiorotto, Wolfgang G. Brunner, Manfred Schöpf

"Deep mixing methods can be used economically for the construction of cut-off or excavation support walls where other systems such as traditional soldier beams and lagging walls would yie ld unsatisfactory performance, where the installation of vibrated or driven sheet piles could cause vibration induced settlements and where concrete diaphragm walls would be time consuming and expensive. The new CSM method can largely replace the more conventional single or multiple auger methods of soil mixing or jet grouting. The cutter tool is similar to a cutter used in diaphragm walls or cut-off walls and is operated with a Kelly mounted on a drill rig. With this system much deeper walls can be installed and even hard soil layers can be penetrated. CONVENTIONAL SOIL MIXINGIn 1962 Norman Liver patented an auger-based soil mixing technique that has become the basis for the world's current technology.The deep mixing method (DMM), as it is known today, is an in situ soil treatment and improvement technology where the soil is blended with binders and/or other materials that are introduced in a slurry or dry form.Typically one or more hollow, rotating mixing shafts tipped with some type of cutting tool are mounted vertically to the mast of a base carrier and are driven into the ground by hydraulic or electrically powered rotary heads. The shafts above the cutting tool may be further equipped with discontinuous auger flights and/or mixing paddles. The binder is injected through the hollow shafts to nozzles located near the cutting tool where it is mixed with the ground to form columns of treated soil.Individual column diameters range from 0,6m to 1,5m and may extend to 40 m in depth. They can be arranged individually or in contiguous or secant patterns to produce a wide range of treated soil structures on both land and marine projects. Typical configurations are: Single elements, rows of overlapping (secant) elements, grids, lattices and blocks (Fig. 1 )."

Jan 1, 2005

By Joshua R. Omer

A numerical model is developed for predicting the load transfer and settlement behaviour of vertically loaded, bored cast in-situ piles. Based on analysis of full-scale pile tests, closed-form equations are formulated to uncouple the shaft and base transfer resistance components of the pile/soil system. Appropriate parameters are introduced to take into account: (i) the shaft resistance distribution in unlined and partially lined piles, (ii) the effects of ?soft toe? (voided toe pile) behaviour on base resistance development. For convenience, an interactive computer program has been developed in Matlab? with a user friendly interface system. The program can be applied to predict the complete load-settlement curve and axial force distribution in bored cast in-situ piles if reliable soil test data are available. To demonstrate its validity, the proposed method is applied to 4 test piles, which are also analysed using two previously published methods: (a) elastic solution method and (b) layer discretisation method. Methods (a) and (b) above are based on load transfer (t-z) and finite element models respectively. It is shown that the proposed method yields axial force distributions and load-settlement curves that are in good agreement with the observed pile test data.

Jan 1, 2010

By Klaus Pöllath

This paper describes mitigating measures and the design of compensation grouting which will be executed from deep shafts of the Amsterdam North/South Metro line project. Due to the specific conditions for TBM-tunnelling in Amsterdam (historical buildings on pile foundations near the tunnel and soft soils with high groundwater levels) tunnel construction necessitates mitigating measures, such as compensation grouting or soil freezing. Züblin developed a special shaft construction method for critical distances to buildings. For the compensation grouting Züblin developed a new software tool, called SOFIA, which controls and visualizes and thus optimizes the entire injection process. This tool significantly increases the efficiency of the injection works while reducing the geotechnical risks.

Jan 1, 2006

By Inn-Joon Park

Major problems associated predicting soil-structure interaction behavior are based on the fact that soil is neither homogeneous nor elastic and soil properties are spatially variable. There also exist significant coupling problems between the behavior of the structure and geologic media. When designing foundation or other geotechnical structures, the load transfer between the soil and structure takes place at the contact surface. This surface is called the interface. The behaviors of interface play an important role in the load-deformation response of soil-structure interaction systems. The purpose of this study is to develop improved model for simulation of saturated sand-steel pile interface behavior based on a general concept, called the disturbed state concept (DSC), which can characterize the behavior of saturated soils under dynamic loads. In this study, the Disturbed State Concept (DSC) constitutive model is calibrated and modified for steel pile-saturated sand interface and interaction by using the continuous hardening model for relative intact (Rl) state and the critical state model for the fully adjusted (FA) part in the saturated sand material. The general formulation for implementation has been developed. Then, the DSC model with modification for interface and saturated sand is implemented in finite element program based on the generalized Biot's theory. The interface tests under one-way monotonic and two-way cyclic loading and cyclic triaxial tests are executed for defining the parameters for interface and surrounding soils. Based on these parameters, steel pile-saturated sand interface and interaction are numerically simulated using the finite element program modified in this study. The DSC predictions show improved agreement with the observed results from laboratory test.

Jan 1, 2002

By Christopher J. Pacitto

This paper presents a case history of an engineered, monitored, and tested program that provided an effective and satisfactory basis for the completion of pile foundations for Twin Dolphins 1 at La Peninsula Condominiums located in the Isles of Capri in southwest Florida, U.S.A. An 8-story building (withl-story parking underneath) along with recreational facilities (such as a swimming pool and tennis courts) had been planned for final construction. Following an evaluation of various foundation alternatives, a precast prestressed concrete (PPC) pile-supported system was selected. The building foundations were designed for pile capacities of 445kN (50 tons) and 890kN (100 tons) in compression and 133kN (15 tons) in uplift. A test pile program was performed to provide site-specific pile driving data, verify design assumptions, determine production pile lengths, and evaluate pile driving criteria. A total of 24, 356 mm (14-in.) square, 19.8 m (65 ft) PPC concrete piles were driven and dynamically load tested utilizing a Pile Driving Analyzer (PDA) within the building limits. Dynamic monitoring during probe pile installation and restriking was performed to estimate the ultimate capacity of the piles and to evaluate driving stresses during installation. CAPWAP analyses were preformed on PDA data to better estimate pile capacity, resistance distribution, and predict pile freeze (increase in pile resistance with time) and thus optimized the production pile lengths. Upon completion of probe pile installation, 12 of the probe piles were tested using the Pile Echo Tester (PET) function of the Pile Integrity Sonic Analyzer (PISA). PET testing was performed to evaluate the integrity of piles which had exhibited high driving stresses during PDA testing. Information gathered during the probe pile driving program was effectively utilized as part of the overall quality control program to install a total of 539 PPC piles (including 24 probe piles) within the building limits at the project site to depths ranging from 9.1 to 19.8 m (30 to 65 ft) below the existing ground elevation as part of the foundation support system. Prior to installation of probe or production piles, a termination criterion was established using 1-dimensional wave equation analyses in addition to the design pile embedment requirement. The predicted pile capacities compared very well with the capacities from the CAPWAP analysis for probe piles. Use of geotechnical instrumentation and PDA assisted technology enabled each foundation support element to be constructed to its optimum capacity and at optimum cost. Furthermore, by using PDA the consultant was able to quantify a difficult to measure geotechnical phenomenon termed "pile freeze" which eliminated costly overdriving and unnecessary splicing of piles.

Jan 1, 2002

By Joram M. Amir

Even when they are cased! [ ] In bored piles, as well as in drilled shafts, and in caissons too, defects will occur! [ ]

Jan 1, 2001

By D. Waite

The Chairman opened the session by wondering why so few papers on Maritime Structures had been received for this conference. Perhaps because the marine environment is so hostile and the access so difficult that engineers tend to be more prudent about new ideas and designs. Dennis Waite noted the number of grey hairs in the room - grey hairs which could be equated with experience gained the hard way. He hoped that this experience would be passed on in the discussion period of this session. The Chairman was delighted to welcome two authors from China, Mr Sun and Mr Liang. He was most grateful on behalf of the conference for their efforts both in preparing their papers and for being able to present them. He regretted that Messrs Noce and Fedolino were not able to present their paper and then welcomed Mr Christensen from Denmark who would present the first paper.

Jan 1, 1991

By S. D. Zhang

The first reinforced earth railway bridge abutment in China has been successfully constructed of September, 1985 under the supervision of the Reinforced Earth Researth Group of Shanghai Institute of Railway Technology. In order to verify the reliability of the designed structure and its behaviuors, the 1:10 reduced scale model tests in laboratory and field tests on the actual structure during construction were proceeded. Various loads of different positions were charged, the vertical and lateral earth pressure in the filling soil, the stresses developed in the reinforcements, and the deformations of the models or the actual structure were recorded in those tests. The behaviors recorded are presented and discussed in this paper.

Jan 1, 2010

By Danny Winters, Wesley Schmutzler, Christopher Lewis, Matteo Bertoni

"SR 83/US 331 is a primary North/South roadway in Walton County that is a crucial link for tourism and commerce between the Walton County beaches and the heavily traveled I-10 corridor in the panhandle of Florida. The facility also serves as the primary hurricane evacuation route from southern Walton County. This 3.4 mile project involves expanding the current two-lane crossing of Choctawhatchee Bay to a fourlane facility to increase capacity and dramatically improve mobility within the corridor. One of the major goals of the project is to perform ground stabilization using Deep and Shallow Soil Mixing (DMM & SMM) along existing causeways. Ground stabilization is required due to the existence of moderately deep very loose soils that have settled considerably over the years. As a result, the Florida Department of Transportation (FDOT) incurred significant maintenance expenses and was unable to maintain an acceptable ride quality. FDOT considered soil mixing as one option to control this settlement. Quality Control for soil mixing relies heavily on the monitoring system used to control mixing parameters. This paper will examine in detail, the reporting of the Drilling Mate System (DMS) used to ensure the quality of each soil mixed element.INTRODUCTIONThe Florida Department of Transportation (FDOT) issued a Design-Build Maximum Price Request for Proposal (RFP) for the Choctawhatchee Bay Bridge expansion. The design-build (D/B) team of Skanska/Parsons Brinckerhoff was awarded the contract. The D/B team, in order to meet the unique deep ground improvement challenges of the Choctawhatchee Bay Bridge Project, selected Foundation & Geotechnical Engineering (FGE) as the engineer to design the ground improvement and TREVIICOS South (TIS) to execute the works.The FDOT in their RFP states that “either bridge or utilize a deep ground improvement method to stabilize the three segments of the existing earthen causeway” and “one possible method of deep ground improvement which is considered viable is deep soil mixing”. FGE developed a proposal to provide a unique rigid transfer platform to effectively stabilize the existing causeways. This platform (Fig. 1) consists of an upper 10 ft thick stabilized soil layer which transfers axial load to a series of deep columns. This robust system guarantees superior durability, ride quality and pavement condition and will exceed all required design and performance criteria including, “Less than 2 inches of settlement within a 1,000-foot section”."

Jan 1, 2017

By Y. G. Li

The design and construction of the hand-dug caisson pier foundation of the Shenzhen International Trade Centre are described in the paper. In addition discussions and inquires about the load-bearing capacity of the hard bedrock are offered.

Jan 1, 2010

By J. M. Pei

In this paper, the nonlinear finite element analysis is used to study the support system of a tunnel which is designed to pass through deep-embeded stratum. The rock mass is rather intact, though a section of tunnel will pass through the weak belt. Under the influence of the high ground stress, the condition of stability and the form of support become complicate. This paper, talcing into account the nonlinear properties of rock mass and the Interaction between rock, and support, makes a comparison between the two kinds of soft and rigid support systems, and analysed the changes of their bearing forces.

Jan 1, 2010

By Tatsunori Matsumoto

In order to investigate the variation of the load-displacement relations of piles in a site, vertical load tests were carried out on 25 small diameter steel pipe piles. Out of 25 piles, 15 piles were close-ended pipe piles attached with a blade at the pile toe and 10 piles were open-ended pipe piles. To carry out these load tests in a short period, two types of rapid load test methods, Spring hammer load test and Falling mass load test, were employed. The load tests of all piles were completed in two days with 180 blows in total. In order to estimate a static load-displacement of a pile, non-linear damping method was used. It is shown from the test results that the performance of the pipe piles such as the ultimate pile resistance and the initial pile head stiffness is improved by re-driving.

Jan 1, 2006

By H G. Poulos

"This paper sets out a simplified approach by which the practical foundation designer can undertake the relevant calculations to satisfy the requirements for deep foundation design in seismic areas. The following matters are dealt with:a. Design issues that should be addressed;b. Pile design for axial loading, including the possible effects of liquefaction;c. Pile design for lateral loading where liquefaction does not occur;d. Pile design for lateral loading where liquefaction does occur;e. Measures to mitigate against liquefaction effects.The paper is a modified version of a paper presented in 2013 to the 19th NZGS GeotechnicalSymposium, Queenstown, New Zealand.1. INTRODUCTIONConsideration of the effects of earthquakes and seismic loadings is an increasingly important aspect of modern foundation design, and most contemporary standards have a mandatory requirement for such consideration. For example, the Australian Piling Code, AS 2159-2009, states that “a pile shall be designed for adequate strength, stiffness and ductility under load combinations including earthquake design actions”. However, the methods by which such considerations can be undertaken are generally not set out in the standards, and many approaches have been utilized, ranging from very simplistic methods to extremely complex computer analyses. Accordingly, there appears to be scope for an approach that is soundly based but which is neither too simplistic nor too complex.Poulos (1989) has suggested that there are three categories of analysis and design, as follows:1. Category 1: empirical methods.2. Category 2: simplified but soundly-based methods.3. Category 3: more comprehensive methods that are soundly-based, and site-specific.The objective of this paper is to set out a systematic but simplified approach which falls into Category 2 above, and by which the foundation designer can undertake the relevant analyses to satisfy the foundation design requirements for seismic regions. Emphasis is placed on methods that do not require “black box” software or which employ complex soil models in which the physical meaning of the parameters is unclear."

Jan 1, 1900

By Pathik Deb Mallik, Shyamal K. Mitra, Rajiv Kishore, Shuvranshu Rout, Manos De

"This paper presents a case study on the design and construction of a deep underground pit structure constructed inside almost a century old existing plant building. The complexity and challenge for the design and construction lay in executing the work in a difficult subsoil condition especially the presence of deep mica schist. The limited space availability in the existing plant for construction work without hampering regular production in other adjoining areas of the plant made the execution more challenging. Experience with difficult subsoil and proximity to old foundations entailed a non-conventional engineering approach while ensuring complete safety in spite of maintaining the normal operation.INTRODUCTIONTata Steel Processing and Distribution Limited (TSPDL) is a subsidiary unit of Tata Steel Limited (TSL) having a CR processing facility inside the premises of Tata Steel Limited. TSPDL intended to install equipment for a new slitting line inside the existing shed including construction of very deep structure called “loop pit” where the strips from cut CR sheets collect in the form of loops and are recovered as scrap. The entire plant is located within the shed of existing plant. The construction of all foundations including the loop pit is to be executed in the limited area without disturbance to normal production work in balance areas of the plant and also maintain safety and integrity of existing structures.The existing shed is an old structure constructed approximately 80 years ago. The building column foundations are gravity type design of brick masonry supporting only the vertical load from the columns. This type of foundation designed with no eccentricity of loading provides no allowance for implementing any foundation stabilizing design. The present project required civil construction for the new equipment foundations safely within this area."

Jan 1, 2015

By Martin Pratt

This paper is an overview of deep foundation engineering in Hong Kong past, present and future. The enormity of the subject compared with the space available makes brevity inevitable. Issues of construction and design are covered and some examples of recent challenging projects are given. The content is aimed at those with an interest in foundations generally, but with limited knowledge of the Hong Kong scene. Reference is made to informative publications for further reading on specific topics.

Jan 1, 2000

By Emöke Imre

A point-symmetrical linear coupled consolidation model with displacement boundary condition is suggested for the description of the consolidation around the pile tip after pile penetration. Analytical solution is given. Main features of the solutions are predicted by the analysis of the system of differential equations and, the boundary conditions.

Jan 1, 2002

By Konstantin G. Ashkinadze

The paper considers performance of piles supporting transient pipe anchors in heavy industrial pipelines. Events such as pump trips or opening and closing of large valves produce short-term dynamic pulses in the pipeline with variable spectral characteristics. Their magnitude is large enough to cause major damage to the pipeline and its anchors, which face horizontal impact loads amounting to hundreds of kN. Design of pile foundations supporting these anchors is often governed by limitation of deflection of the support to prevent overstressing pipeline connections and equipment nozzles. The maximum deflection does not always correspond to the largest load because the stiffness of the soil surrounding the piles heavily depends on the rate of loading. Faster actions encounter stiffer soil response while loads of smaller magnitude applied slowly may be more critical for the deflection time history of the anchor. A typical transient action has both high- and low-frequency harmonics, which makes the response complex. Using load rate-dependent p-y curves published in literature, the paper develops methods of analysis of pile foundations for transient anchors. Pile displacement amplitude – input frequency – natural frequency correlations and time histories of pile response are constructed for typical profiles of transient actions, considering nonlinear soil response to large horizontal loads.

Jan 1, 2016