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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 A. Frits van Tol, Rodriaan Spruit, Jan H. van Dalen

"Abstract In recent years, there have been major problems with deep excavations in urban areas supported by diaphragm walls. In some cases, like the fatal Nicoll Highway collapse in Singapore the quality of the D-walls was not the cause. However in other projects, like the problems with the major leak in the walls of the Boston Big Dig and with leakage in a few projects in Belgium and The Netherlands was related to poor D-wall quality. Leakage through the D-walls at the joints in deep excavations led in these cases to very serious settlement behind the walls, in the case of the North- South line in Amsterdam, there was severe damage to historical buildings. This paper describes ongoing research that focusses i on acquiring more knowledge on and improvement of D-wall installation, in particular the flow process prior and during casting ii on the detection of anomalies prior to excavation and iii on the composition of the concrete mixture in view of a better and more sustainable concrete quality of D-walls.INTRODUCTIONIn the case of deep excavations in urban areas close to neighbouring buildings, diaphragm walls are one of the best feasible solutions for the retaining structure. Although the costs of D-walls generally exceed the costs of alternative wall solutions, the advantages are decisive in many situations. The main advantages of D-walls are the limited impact of the installation on the built environment, the high stiffness and bearing capacity and the retention of water, even at considerable depths. This makes Dwalls often the preferred solution for deep excavations Sometimes the D-walls are the temporary support while for the final stage a complete concrete box is constructed in the excavation. In many other cases the D-wall has the permanent function of retaining soil as well as groundwater.In the last ten years, there have been major problems with deep excavations in urban areas supported by diaphragm walls. In some cases, like the fatal Nicoll Highway collapse, 2004 , the quality of the Dwalls was not the cause. In other important failures like the collapse of the Archives in Cologne, 2008 and Dubai Infinity Tower Flooding, 2007 a combination of design and quality issues played a role. However, the major leak in the walls of the Boston Big Dig was related to poor D-wall quality (McNichol, 2000). Van Tol et al, (2010) describe a number of case studies in Belgium and the Netherlands, with leakage through the D-walls at stop end joints. In several cases with deep excavations these leakage caused serious surface settlements behind the walls. In the case of the North-South line in Amsterdam, there was severe damage to historical buildings. All these cases have generated considerable additional costs and delays, and subsequently public and political concern. Van Tol et al. (2010) present several possibilities to improve the quality of D-walls.Other disputes related to D-walls deal with the quality of the concrete and the sustainability of D-walls applied as a permanent wall. In particular the porosity of the concrete cover is sometimes problematic."

Jan 1, 2014

By Michael D. Justason

This paper details the static and Statnamic load testing on a 600 mm square pre-stressed concrete pile. The pile was located at Pier 15 on the 20 million-dollar Bayou Chico Bridge Project in Pensacola, Florida. The pile was 10.5 meters long and had a design load of 1.3 MN. Three static load test cycles were performed in November, 1996. The Statnamic load test was performed in January, 1997. The Davisson Failure load of the first cycle of the static test was 3.7 MN, and the Davisson Failure load of the Statnamic test was 3.2 MN. The load-displacement curves for the two types of tests were very similar, indicating that the Statnamic load test performed well in the sandy soils. Strain gauges embedded in the pile showed 35% skin friction and 65% end bearing for both test methods. Strain gauges were located at equal spacing at five elevations in the pile. A toe accelerometer verified the rigid body assumption of the Unloading Point Method currently used in the analysis of Statnamic load tests. The data collected from the pile instrumentation was of excellent quality and represents some of the best research to date comparing static and Statnamic load tests.

Jan 1, 1997

By Walter G. Kutschke

Four significant soil nail wall projects in the eastern United States were recently completed with a combined area of 175,000 square feet of finished shotcrete surface. These projects required the use of innovative design and construction methods in order to address various challenges, including slide-prone back slope materials, perched water, highly erodible rock materials, curved wall alignments, very tight construction tolerances and unexpected subsurface conditions. Special focus is given to issues such as bench excavation, soil nail installation methods, shotcrete mix design, anticipated shotcrete quantities, shotcrete nozzlemen qualifications and weather conditions, in order to provide a lessons-learned database for future soil nail wall design and inspector considerations. These projects also underscore the importance of design engineer and soil nail wall contractor qualifications as well as effective communication with the owner.

Jan 1, 2007

By Monica Prezzi

"Auger cast-in-place (ACIP} piles and drilled displacement piles are being increasingly used as foundation elements for structures, particularly in projects requiring accelerated construction or involving the rehabilitation of foundations of existing, overstressed structures. Auger cast-in-place piles (also referred to as continuous-flight-auger piles) are widely used to construct the foundations of all types of structures. There are many different types of drilled displacement piles, with the installation methods varying according to the equipment used. Depending on the specific rotary piling technology used, responses ranging from those associated with non-displacement to those associated with full-displacement piles are obtained. Conventional pile design methods do not account for how the various construction techniques involved in auger piling change the soil state around the pile during installation and, hence, cannot accurately estimate the pile resistance in a consistent way. Research on this subject, identifying the different variables that must be accounted for in design and linking these variables to installation methods, is lacking. This paper describes the different piling methods available for auger cast-in-place and drilled displacement piles, the equipment used to install them and the quality control processes typically used. It also reviews some of the design methods currently used.IntroductionDeep foundations are extensively used in geotechnical engineering practice. The wide spectrum of piling methods results in a variety of pile types. Each type behaves differently, depending on the installation or construction methods. On one end of the spectrum are non-displacement piles, the classicql examples of which are bored piles or drilled · shafts. These piles are constructed by removing a cylinder of soil from the ground and replacing it with concrete and reinforcement. On the other end are full-displacement piles, such as closed-ended pipe piles or precast reinforced concrete piles, which are typically driven into the ground. Driven piles preload the materials below the toe of the pile and displace the soil surrounding the pile shaft laterally during the installation process. Therefore, displacement piles are, in general, more likely to have a stiffer response than non-displacement piles. This is true particularly in the case of sandy soils where displacement causes densification."

Jan 1, 2005

By Jean-Pierre Hamelin

Ground movements induced by underground excavation are always of critical concern, particularly in urban areas. Compensation grouting now appears as a safe means to control these movements. The paper presents new advanced systems developed by the specialist contractor to bring, at all stages of the project, an efficient control of operations and presents a case history taken from the project at Tren Urbano, Rio Piedras Section, constructed beneath an historic commercial section of San Juan de Puerto Rico.

Jan 1, 2000

By Philip Bonanno

The first major project in Boston's new access to Logan Airport was an Immersed Tube Tunnel which extended 3,600 ft. from South Boston to East Boston across Boston Harbor. Twelve tube sections, 300 ft. long x 80 ft. wide x 40 ft. high, were lowered into an excavated trench which was then backfilled. The depth of the trench at mid-channel was approximately 100 ft. below mean high tide. At the East Boston end the tube terminated close to the present shoreline. At the South Boston end the tube terminated approximately 600 ft. inland from the shore line where a ventilation building was required. The depth to subgrade from existing ground at the ventilation structure was approximately 85 ft. The soil profile at this location consisted of 50 ft. of miscellaneous rubble fill, 25 ft. of Boston blue clay, and 10 ft. of glacial till. A small amount of weathered argellite existed at the north end of the structure. Part of the Morrison Knudsen, Interbeton, J.F. White, Joint Venture contract to construct the Immersed Tube Tunnel (ITT) was the construction of a cofferdam at the tube/ventilation building interface. The ventilation building was to be built as part of another contract. The construction of the cofferdam and the excavation to the building subgrade was the responsibility of J.F. White Contracting Company.

Jan 1, 1994

By D. Michael Holloway

The realignment of Interstate 880 replaces the double-decked (Cypress) viaduct collapsed in Oakland, California during the 1989 Loma Prieta Earthquake. The California Department of Transportation (CALTRANS) evaluated several pile foundation schemes for supporting the proposed structures. Structural support demands led to the selection of steel pipe piles (16-, 24-, and 42-inch-(406-, 610- and 1067-mm-)diameter), filled with concrete and steel reinforcement. Deep penetrations required through layers of very dense/cemented sands in some locations, caused serious drivability and pile integrity concerns. The need for large pile driving hammers and large diameter steel pipe piles pushed the engineers and prospective contractors well beyond the limits of local experience. Such questions as the feasibility of driving the pipes closed-ended through dense upper strata, and quantifying the effects of installation on the long-term capacities of the piles, led CALTRANS to develop a comprehensive pile test program to address the design and construction issues effectively. The results were furnished to prospective bidders on the production stages of the ensuing contracts.

Jan 1, 1996

By Amit Srivastava, Monica Malhotra

In a congested city or urban area, so called “lifeline of the city”, i.e. Gas, Electricity, telecommunication, as well as other utilities or facilities are supplied or transported underground through buried pipes or utility tunnel. Sometimes these buried pipes or utility tunnels are deep underground and interfere with the foundation of new structure. It is highly probable that a pile foundation is placed near an existing underground buried pipe or utilities tunnel and may influence its load bearing capacity. Hence, estimation of reduce load bearing capacity of the pile foundation placed near the existing buried conduit or utility tunnel is a complex soil-buried structure interaction problem. It is further complicated owing to uncertainty in estimation of geotechnical parameters of foundation soil due to measurement and testing errors, inherent soil variability and model transation. Under such circumstances, load bearing capacity is best assessed in probabilistic framework or through reliability analysis. The present study demonstrates how concept of response surface method (RSM) in conjunction with Numerical Analysis and First Order Second Moment (FOSM) methods can be combined to per the reliability analysis. The study answers the following question “reliability in reduction in the load bearing capacity of single pile placed near the existing underground pipe or utilities tunnel”. It is demonstrated that the approach provides first hand ination on the reduction in the load bearing capacity and then estimate the reliability of that estimation in terms of an index called Reliability Index (). Such preliminary investigation can be useful for advocating the detailed analysis as well as in the decision making for relocation of pile foundation.

Sep 1, 2022

By Zhang Baoshan

In this paper, the forced features and dynamic behaviors of stone-column composite foundation are concisely related. The characteristics of Rayleigh wave method is summarised. This method is proposed in which, the stress ratio of the stone-column to the surrounding soil and the bear­ing capacity of the composite foundation are determined. Through the engineering cases, it is shown that, checking and evaluating the composite foundation in this method, is feasible, with high speed and low cost.

Jan 1, 1991

By Walter Ensinger

Working safely means working cost-effectively. Every "dangerous occurrence" and - even more so - every industrial accident causes disruptions in the planned course of construction. Besides moral and legal obligations, economic aspects are therefore also factors motivating increased efforts towards optimal prevention: improvements in work safety and protection of health are wise investments! Ever since its earliest days, the European Federation of Foundation Contractors (EFFC) has made this subject one of its key objectives and therefore set up a Safety + Environmental Working Group, in which experts from the member organisations exchange national experience and develop proposals for "best practices". The paper presents current developments and results from the work of the S+E WG with particular reference to the project "Ideas for Safety Improvement".

Jan 1, 2006

By Charles F. Seemann

It is with considerable trepidation that I set out to defend "litigation" to Design Professionals (DPs), as a better method of resolving disputes than arbitration, in the light of my personal feeling that an increasing amount of America's productive process is being squandered in litigation. Newer methods of dispute resolution, particularly arbitration, are fashionable, and opponents of these schemes risk being viewed as cynical or self-serving. My quandary is heightened since for some smaller disputes, arbitration seems clearly the better choice. I must concede, for example, that when the cost of dispute resolution--i.e., the cost of the process (such as arbitrators fees, attorneys fees, etc.), plus the cost impact of the non-productivity of involved employees--approximates the amount of the dispute, controlling that cost may be as important as a correct resolution. This principle is particularly true for small disputes arising during the progress of a project; it is probably more cost-effective for all parties to resolve their disputes quickly than permitting the dispute to drag out.

Jan 1, 1988

By Jogeshwar P. Singh, Mohamed Ashour

The Soil-Foundation-Structure-Interaction (SFSI) problem involves Kinematic Soil- Foundation Interaction occurring during large (cyclic and permanent) ground deformations as well as Inertial Foundation-Structure Interaction occurring during shaking all of which take place while the soil and possibly structural properties degrade with time. The design of the deep foundations for liquefaction induced lateral spread loads include estimation of passive pressure applied by the liquefied material as well as the amount of anticipated displacement. Coupled analyses for SFSI problems that account for liquefaction induced lateral spread and their interaction with the deep foundation system can be performed using sophisticated numerical modeling techniques based on finite element and/or finite difference methods using computer programs such as FLAC or OPENSEES. Such complete SFSI analyses are very tedious and expensive and not feasible for most projects. In 2011, California Department of Transportation (Caltrans) released guidelines for foundation loading and deformation due to liquefaction induced lateral spreading. This simpler prescriptive approach combines empirical and analytical methods through decoupled analyses using computer programs such as LPILE and SLOPE-W together with liquefaction induced lateral spread estimates based on published empirical equations. Pile group effects and pile caps are accounted for using a concept of super-pile. In this paper, we discuss the solution of the same lateral spreading related SFSI problem using computer program CGI-DFSAP (CGI-Deep Foundation System Analysis Program) based on the strain wedge theory that can account for liquefaction, lateral spreading, pile groups, pile caps and nonlinear behavior of piles in a more coupled manner to analyze the foundation system under the lateral spread loadings. CGI-DFSAP can be used to analyze piles in sloping ground conditions as well as piles beneath the abutments near a free-face slope. We have included Strain Wedge Model (SWM) solutions using CGI-DFSAP of several field and laboratory case studies of lateral spreading related to pile foundations. Finally, we have also included the SWM solution of one of the Caltrans (2011) example problems.

Jan 1, 2015

By Alexander Filotti, Richard Kalson

"1. INTRODUCTION- WHAT IS P3 OR PPP ?The Public Private Partnership (PPP or 3P) is a project delivery scheme based on the government providing land and/or a concession agreement, and on a private entity providing the design, construction, financing, operation and maintenance of the project for an extensive duration of time (up to thirty years). At the end of the operation-maintenance period, the project is turned over to the public entity, which fully owns the project at all times. While there are many PPP delivery schemes used around the world, for the present paper, we are going to analyze the impact of the Design-Build-Finance-Operate-Maintain (DBFOM) scheme on the deep foundation specialty subcontractor. There are couple of reasons that the PPP delivery system started to be used and implemented not only by developed nations (e.g. United Kingdom, USA etc.), but also by the International Development Bank for delivering major infrastructure projects in developing nations. From the point of view of government agencies, some of the reasons to use PPP are the following:??The primary use of private capital in an era where borrowing and/or supplemental taxation represents too much of a political risk. Budget deficits and taxation limits are extremely hot topics in every election (national or local) and the level of education of the electorate in this area is making it more and more difficult for politicians to use borrowed funds and additional taxation finance sources for public projects. At the same time, we see an increase in the social expenditures of the government in parallel with a needed increase in expenditures on infrastructure due to aging and neglect.??Bundling the construction risks with the operational and maintenance risks naturally pushes the private entity to increase the level of innovation and communications in the primary phase ( the construction phase) in order to develop future process based upon the innovation and communications utilized in the operation and maintenance phase of the project. This is true if contractual incentives are properly structured because “all revolves around incentives. In a world of ‘incomplete’ contracts, where it is difficult to foresee and contract about uncertain future events, it is important to get the incentive structure right” (Grimsey and Lewis, 2004).??The transfer of very expensive risks such as differing site conditions, schedule, design, construction, maintenance and operation costs from the public authority to the private entity.??The timespan of development and construction of a PPP project is usually shorter than the traditional procurement process (e.g. “ the I-595 P3 provided capacity improvements fifteen years sooner than a conventional plan would have offered. In Maryland, an innovative expansion of the Seagirt Marine Terminal in the Port of Baltimore was completed two years ahead of schedule due to the P3 model. As a result, the Port of Baltimore is only the second port on the US East Coast to have unrestricted access to both a fully functioning 50-foot channel and 50-foot berth.”)"

Jan 1, 2017

By Sun Jiale

This paper presents a brief description of information construction technology for supported excavation to assure satisfactory performance of engineered system. As a successful example of application of the technique, quite a few troublesome problems, such as high groundwater level in soft ground and crowded buildings around the excavation, were solved satisfactorily in the construction of the new tower of Guangzhou Overseas Chinese Manison.

Jan 1, 1991

A technical exhibition was held in conjunction with the 4th DFI International Conference on Piling and Deep Foundations, Stresa. The exhibition was located in the ground floor of the Conference Hall. It was open from 15.30 on Monday April 8 till 16.30 Thursday April 11, 1991. The following is an alphabetical list of firms who took part. 1) A.P. VAN DEN BERG MACHINENFABRIEK B.V. P.O. BOX 68 8440 AB HEERENVEEN The Netherlands Tel: +31 5130 31355 Fax: +31 5130 31212 Stand Executive: A. Duyfjies

Jan 1, 1994

By Michael J. Brown

It is often necessary to undertake some form of pile testing to verify design calculations. Historically this has been limited to static and dynamic tests. Newer rapid testing methods such as Statnamic are seeing more frequent use. This form of testing can be advantageous due to short set up time and test duration. Although the methodology suffers from a lack of formalised guidance and may prove difficult to analyse in certain soil conditions. This paper investigates the suitability of Statnamic testing and analysis for a range of soil and pile types as well as different installation methods through a number of case studies undertaken in the UK. Recommendations are made on test specification and analysis.

Jan 1, 2006

By Shamsher Prakash

Equivalent spring constants for analysis of footings is a function of Young's modulus of pile material (Ep), shear modulus of soil (Gs), and geometry of the footing and/or piles. Shear modulus is strongly strain dependent in soils. Therefore, the spring constants are strain dependent, which is acceptable to the Geotechnical engineers. However, structural engineers prefer to use spring constants as a function of displacement, rather than strain. In order to develop these relationships, appropriate relationships between strain and displacement are needed. Also, modulus degradation with strain needs be built into these relationships. Description of spring constants kx , ky, and kz in x, y, and z direction and k?, k?, k?, about x, y, and z directions are relatively simple. However, description of kxø and ky?, the cross-coupling spring constants depend on 2 - components of displacement and rotation. Thus, there are 8 spring constants and likewise there are 8 damping constants. Approximate strain-displacement relationships on which displacement dependant k's and c's are based are presented with appropriate equations, and a numerical example is included illustrating k's and c's as functions of displacement.

Jan 1, 2002

By Patrick J. Hannigan

A comparison of 40 statically and dynamically load tested piles was performed to evaluate the variation between testing methods. This evaluation indicated an agreement of 10% to 15% could be obtained when the available static resistance is fully mobilized by both methods and when time dependent capacity changes are minimized. Dynamic pile testing recommendations for minimum induced impact force, ram weight to pile weight ratio, and considerations for time dependent capacity changes are presented.

Jan 1, 1987

By Bas R. Hemmen

GeoBrain is a facility at GeoDelft with the purpose to provide society with all relevant geo-engineering knowledge and experience in a structured way. On the basis of the available knowledge and experience engineers, decision makers and construction supervisors can come to a fast, reproducible and objective choice, taking into account the consequences. The paper presents examples from the GeoBrain experience databases and forecasting models developed for foundation engineering and directional drilling, or: "GeoBrain Foundations" and "GeoBrain Drilling". GeoBrain is closing the gap between theory and practice. It is aimed directly at reducing uncertainty and the costs of failure, thereby increasing the quality of profession and minimising the risk in geo-engineering works.

Jan 1, 2006