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By David B. Paul

"ABSTRACTThe US Army Corps of Engineers (USACE) has 704 dams in their inventory and over 100,000 miles of levees with a capital value of over $150 billion. Currently, there are 319 dams that are classified as high hazard and have actionable failure modes that will require structural modifications. The most frequent actionable failure mode associated with the inventory is seepage and piping. One of the most effective engineering solutions is the installation of a cutoff to limit seepage. Currently, USACE has over $1.5 Billion of cutoff wall projects under construction and/or design. Given the magnitude of the dam and levee safety issues, USACE is developing a new Engineering Manual (EM) titled “Seepage Control Cutoffs for Dams and Levees.” This EM covers all of the methods to construct cutoff walls. USACE has partnered with the Deep Foundation Institute (DFI) in preparation of the EM to ensure that it is comprehensive and draws from the expertise of the specialty foundation engineering companies that design, manufacture, and construct seepage control cutoffs around the world. The EM contains case histories as well as a comprehensive project statistical summary and guide specification paragraphs. The goal of USACE was to make the EM a state of the art document for use by Districts.HISTORYSlurry wall construction techniques were developed in the late 1940’s in Italy by ICOS. The first use of the slurry trench method of construction in the United States was by the USACE Memphis District in September 1945, to form a partial cutoff along the Mississippi River levee on the Arkansas side of the river just below Memphis, Tennessee. The idea for the project probably evolved from the use at that time of puddle clay trench cutoffs combined with the use of drilling mud for advancing borings. A paddle wheel mixing device was constructed for making slurry from native clays. Trenches were dug to a 20-ft depth using a trenching machine and to a 35-ft depth using a dragline with a 100-ft boom and 2-cu-yd bucket. Backfill was mixed in windrows at the site from hauled-in clay gravel and native materials and pushed into the trench by a bulldozer when the length of the trench was equal to about twice the trench depth. It is amazing that after almost 70 years, the technique is still about the same as it was when first developed by the Memphis District. A soilbentonite cutoff was constructed under the Kennewick Levee adjacent to the Columbia River as part of the McNary Dam Project in Washington by the Walla Walla District in 1952 The first application of a soil-bentonite slurry trench cutoff for control of underseepage at a major earth dam was at Wanapum Dam on the Columbia River in Washington in 1959.The first cement- bentonite cutoff in the United States was constructed at the Tilden Tailings Project to store tailings from the Tilden Mine in Michigan in 1976. The first cement-bentonite cutoff constructed at a dam on a river retaining a reservoir in the United States was completed in 1978 at the Elgo Dam (formerly the San Carlos Dam) in Arizona.The USACE has designed and constructed some of the deepest and most complex cutoff walls for dams since the 1970’s. The first major concrete panel cutoff wall constructed in a dam in the United States was at Wolf Creek Dam (Nashville District) by the ICOS Corporation between 1974-77. The dam has a long history of seepage issues associated with the karst geology that comprises the foundation. In 1968, about 17 years after first being impounded, wet areas, muddy flows in the tailrace and sinkholes in the downstream toe adjacent to the switchyard occurred."

Jan 1, 2014

By Aly M. Mohammad

State and federal agencies during rehabilitation of existing bridges may require the existing bridges to be evaluated under seismic conditions. If the bridge does not perform under the seismic event, the bridge may require seismic retrofitting. Bridges are classified as: Critical, Essential, and Others according to their importance. Geotechnical considerations play a major role in evaluating the bridge behavior under a seismic event. Subsurface conditions influence the magnitude of ground acceleration and hence the forces and moments on the superstructure. This paper will provide a detailed description of the geotechnical aspects associated with the seismic retrofit evaluation for the 12th Street and 14th Street Viaducts located in Jersey City, New Jersey. The paper will also present a description of the geotechnical investigation program including seismic cross-hole surveys to determine the dynamic soil parameters, including the results of site-specific response spectra for both the 475 and 2475-year events. Liquefaction assessment methodology utilizing an equivalent factor of safety will also be described and the design method used will be summarized. In general, the pile foundation is modeled as 6x6 foundation stiffness matrix with 36 stiffness coefficients at the center of the pile cap. The seismic loading on the foundation is evaluated in a pseudo-static analysis, where the dynamic earthquake-induced loads are presented by static forces and moments. The computer program FB Pier was used to evaluate the foundation stiffness. The moments, axial loads, and shear are input into the FB Pier model. The stiffness of the foundation is determined and the results are then input into the Structural model to determine new forces and displacements. Adjustments are made until the loads are compatible with the stiffness used. The understanding of the geotechnical conditions at the 12th Street and 14th Street Viaducts and the coordination between the Bridge and Geotechnical Engineers were able to provide significant cost saving to the Owner. The Design Engineers were able to retrofit the existing Viaduct foundations with reasonable number of additional piles. It is believed that the results and finding presented in this paper will benefit both the Bridge Engineers and Geotechnical Engineers by highlighting the importance of interaction between the two disciplines.

Jan 1, 2006

By Paul M. Wiltcher

This paper discusses how benefits in engineering design can be achieved from combining existing GRP concrete design guidelines with carbon steel design codes primarily made possible due to the increase in the constitutive properties of modern composite rebar or GRP. It also examines the technical and practical considerations necessary to both construct and ensure the integrity of composite rebar during transportation and handling on site and the measures taken by Franki-Cementation Joint Venture to ensure the safe deployment of the GRP in the workplace on the Noord/Zuidlijn Project in Amsterdam between 2003 and 2006.

Jan 1, 2006

By Kevin W. Cargill

In September 2004, Hurricanes Frances and Ivan caused the Pigeon River in western North Carolina to flood. This flooding eroded the embankment below Interstate 40 (I-40) and sent one of the eastbound lanes, along with the roadway shoulder, into the river below the embankment. North Carolina Department of Transportation (NCDOT) needed to reopen all the lanes of I-40 as soon as possible and considered this damage to be an emergency situation. NCDOT contracted Schnabel Foundation Company to design and build a repair that would keep this important interstate open and reestablish the eastbound lane. The obstacles included limited work room, the requirement of keeping the remaining lanes of I-40 in service, and producing a final product that would be relatively maintenance free and last at least 100 years. The proposed repair had to consider that the existing interstate was founded on a rock fill that was constructed from rock blasted off the adjacent mountain side. The selected design included two, tied-back micropile walls to address these obstacles and other issues. Each of the walls were constructed of 10.75 inch diameter micropiles and corrosion-protected tieback anchors installed through the existing rock fill into competent bedrock, concrete wales, and a reinforced shotcrete facing. This successful project was completed during the coldest months of the year and within the timeframe established by the State of North Carolina. This paper will discuss the design and construction of the repair and the many challenges that had to be overcome.

Jan 1, 2006

By Roy A. Bell

A 200-foot diameter, 72-foot high petroleum storage tank was built in a hillside ravine where a portion of the site contained soft clay fill. Soil-cement piles, 40 inches in diameter and up to 38 feet long, were installed to support the tank shell and ringwall, and a portion of the tank floor by drilling into the stiff to hard underlying soils and weathered bedrock. The goal was to provide a strong enough foundation to resist the seismic tank shell loading and to minimize differential settlement of the tank shell to avoid out-of-round clearance problems between the shell and floating-roof. A cantilevered retaining wall up to 8 feet high was constructed around a portion of the tank perimeter by inserting steel H-beams into soil-cement piles. The cantilever soldier piles for the retaining wall were installed from a temporary earth embankment on the hillside directly over the top of the wall. The temporary embankment was then removed and the tank pad was cut to grade in front of the soldier piles. Some of the soil-cement piles for both the tank foundation and retaining wall could not be advanced to design depth because the drill/mixing tools could not penetrate to the required depth in the hard soils/bedrock. Smaller diameter borings (22 inches in diameter) were drilled through the centers of the short-of-design soil-cement piles to the design depth and then backfilled with concrete.

Jan 1, 1997

By Paolo Cavalcoli, Marco Ziller

"ABSTRACT: In the year 2010 the State of Denmark together with the Municipality of Copenhagen, launched a very important and complex Project : the complete construction of a new double Subway Line :the CITYRINGEN.Copenhagen is the capital with a metropolitan population of 1,9 million.This line is like a ring placed in the very town center which includes all the most historical and monumental buildings and churches, with a total length of 17 km, and the presence of 17 stations plus 4 service shafts.The buildings have been built in the last centuries in an area where the groundwater is near to the surface and there are lakes and channels: the techniques adopted were advanced for those times, but limited as far as regards settlements and resistance to horizontal movements.The soil consists in 2 main groups.1.Upper sediments of the glacial ages : thickness total = 5-20 m composed by clay- silt-sand-gravelcobbles- granite boulders and flint in blocs and in layers : frequency and size of these obstacles wherenot determined.2.Limestone layers : 2a. upper limestone : highly fractured ,highly permeable2b.Itermediate limestone : less fractured, medium permeability.2c. Lower limestone : almost not fractured, low permeability.2d Bryozoan limestone : composed by fossils with microscopic dimensionsIn all the limestone formations there are important layers of flint , having thickness variable up to 3 m and important extensions. Water : in a part of the areas of the Cityringen the water is drinkable and utilized in the public waternet.Pollution: there are polluted zones due to previous industrial activities. Benzene areas have been identified, and for those areas special protections against pollution have been implemented.METROSELSKABET ,the public owner of the Cityringen,has set as priority to operate for the construction of the Cityringen the full protection of the environment and the respect of all the stakeholders :Very strong limits for the exhausted gas emissions have been introduced, by far stronger than those applied from the State of Denmark, very strong limits for the acceptable noise emission. And last but not least very important safety measures and procedure to avoid any accident on site."

Jan 1, 2014

By J. Tanner Blackburn, James R. Gingery, Lisheng Shao

Rigid inclusions consist of grout columns installed using displacement auger or vibrated tooling. The columns are typically installed in an array to provide support for footings, mats, or embankments. Due to the relative small column diameter and low replacement ratio, the surrounding soils typically have minimal densification or improvement. A gravel load transfer platform is commonly used above the rigid inclusion head to distribute stresses more broadly to the supported structure. The axial stiffness and geotechnical engineering mechanics of rigid inclusion design are similar to those of deep foundation systems, but they are typically only lightly- or un-reinforced and are not structurally connected to the above-grade structure. The popularity of rigid inclusions is increasing in the Western U.S., where many urban areas are subject to moderate to high seismic hazard levels. However, the performance of rigid inclusions under seismic loading is poorly understood, and seldom addressed in current designs. The elements are brittle, with limited or no ductility and relatively low moment capacity, and therefore may be prone to damage under seismic loading. Three modes of seismic loading should be considered: inertial loading from the structure, kinematic loading from vertically propagating shear waves, and kinematic loading from ground failure- related permanent ground deformation. This paper focuses on the first two modes. A simplified procedure for evaluating kinematic and inertial loading of rigid inclusions is described, and its use is illustrated through application to a site in Southern California. The results show that moderate to severe kinematic loading can generate plastic hinges in the rigid inclusions. Engineering consequences of this hinging could include settlement or bearing failure. INTRODUCTION In this paper the term ‘rigid inclusion’ (RI) refers to grout or grouted aggregate columns that are installed using either drilled or vibration displacement techniques. They are commonly installed in arrays to support vertical loads from footings, mats, or embankments. RIs are not structurally connected to footings they support. Rather, it is typical for a dense gravel load transfer platform (LTP) to be installed as a cushion between the RI head and supported footing or new fill. In cases of RI support of fill embankments, the LTP may be reinforced with horizontal layers of geogrid.

Jan 1, 2018

By Ting Chinsu

Diaphragm wall with tie-back cable is widely used for deep excavation, especially in the area with high density of buildings. This paper presents the measured earth pressure distribution on diaphragm wall during excavation. The earth pressure cells used in field were successfully installed in deep slurry trench by a new type of simplified manipulator. The sizes of the deep excavation are 26m X 36m on plane and 9m in depth. The construction site is located between two multistorey buildings at the main business section of Beijing city. In this paper the field measurements of earth pressure distribution and the analyses based on the comparison between calculation and measurement are very valuable to improve the current calculation method for diaphragm wall design.

Jan 1, 1991

By Vidyaranya Bandi, Madhav Madhira, Kota Vijay Kiran

"Using hyperbolic relationships for the non-linear responses of shaft and base resistances, a method is proposed for estimating initial shaft and base stiffnesses and ultimate shaft and base resistances of a pile from pile load test results. An iterative procedure is used to arrive at the values of shaft-soil and base stiffnesses and the ultimate shaft and base resistances. The method is applied to load - displacement data available from pile load test results to illustrate its efficacy.INTRODUCTIONA pile foundation is the most effective and economical solution in transferring large vertical loads to deeper depths. As the pile is subjected to axial load, the soil mass surrounding the pile is vital in providing vertical support for the pile. The nature of pile–soil interaction is three dimensional and to complicate the problem further, response of soil is nonlinear. Finding a closed form solution to such problem is extremely difficult. Several methods were developed to study and predict the response of the composite pile–soil system. Faruque and Desai (1982) implemented both numerical and geometric non-linearities in their three dimensional finite element model. Rajashree and Sitharam (2001) developed a nonlinear finite element model of batter piles under lateral loading using a hyperbolic relation for static load condition and modified hyperbolic relation, including degradation and gap for cyclic load condition.The ultimate capacity of the pile is estimated considering the strengths and unit weights of soil layers with depth, overburden pressure and other relevant parameters. The estimated capacities always need to be validated by conducting initial maintained load test. The estimated capacity may differ with the actual at site since the values of strength, stiffness, interface resistance between pile and soil, lateral earth pressure coefficient with depth and soil stratification, etc., differ from the design parameters considered for estimating the ultimate capacity of pile. The estimation of axial capacity of piles involves considerable uncertainties in selection of appropriate design parameters and the design rules are not always consistent with the installation procedures/processes involved."

Jan 1, 2017

By Mary Ellen Large

This publication of Deep Foundations Institute (DFI) is intended to provide project owners, design engineers and construction professionals with guidelines for selecting cutoff wall and barrier systems and a general introduction to their methods of construction. Three categories of cutoff wall and barrier construction technology (excavated cutoff systems, in situ techniques, and driven cutoff systems) are presented and parameters for evaluating their design and construction are discussed. The information presented was compiled from the opinions of practicing engineers and construction specialists from the DFI Slurry Wall Committee.

Jan 1, 2021

By Tsunenobu Nozaki

"AbstractThe PRESS-IN METHOD is widely recognised as “an environmentally friendly piling method”. However, this characteristic is only one of the fundamental advantages of the method and this paper presents the most up-to-date capabilities of the method. Due to the evolution in recent years, the Press-in Method is now applicable to 2.5m thick retaining walls, over 50m deep foundations, overcoming rock conditions and confined construction conditions.The Press-in PrinciplesThe basis of the Press-in Method is simple. The Silent Piler presses a pre-formed displacement pile into the ground by static jacking force. The reaction for the Press-in Force is generated by gripping previously installed piles. As a pile is pressed into the ground, “A Pressure Bulb” is formed around the pile toe. Accordingly, higher bearing capacity can be generated compared to driven piles without disturbing the ground and producing any vibration. (A comparison of jacked, driven and bored piles in sand (2005), Deeks et al.)Applicable Pile ProfileThe Press-in Method is applicable to most of the steel piles available on global market i.e. U sheet pile in single form and pair, Z sheet pile, also in single and pair and Tubular Pile as described in Figure 2. Wall thickness of those piles can be 0.3m to 2.5m and moment of inertia of the wall ranges up to about nine million biquadratic cm per meter, which can deliver similar elastic modulus EI (kNm2/m) to 2.0m thick diaphragm walls and can be utilised for extremely deep excavations required in today’s construction industry"

Jan 1, 2014

By Henk E. Brassinga

In Rotterdam a number of underground parking facilities have been built and are under development in the inner city, and in the suburbs. These parking facilities are located at already densely built areas. The design of these constructions has to take into account the impact of the building activities and that of the final construction on the surroundings. In this paper some examples of the different building methods of newly realized underground parking facilities are described, and problems that occurred during the construction are pointed out. In the soil conditions as present in Rotterdam the cost effectiveness of underground facilities can be improved by deepening the parking facility, and at the same time reducing the surface area so that the total parking volume remains constant. In this way the total volume of the diaphragm walls and the costs of the project is reduced.

Jan 1, 2006

By John Wise

Significant movement to an existing slurry wall which serves as a retaining wall on 'O' Street in Southeast Washington, D.C. initiated the Department of Public Works for the District of Columbia to invite specialty contractors to propose a rehabilitation and stabilization for the failed slurry wall. Nicholson Construction Company proposed and was awarded a contract for the construction of an anchored precast lagging and soldier pile wall to be located approximately 4 feet in front of the existing structure with granular fill placed between the new and existing walls. Stabilization of the existing slurry wall also included drilling horizontal weep holes and demolishing the failed panels down to the existing ground surface. A new and improved drainage system was also constructed to increase the amount of water directed toward the existing storm sewer system running along 'O' Street. This paper provides a detailed account of these construction activities.

Jan 1, 2003

By Prasenjit Basu

Drilled displacement piles are being increasingly used as foundation elements, particularly in projects requiring fast construction. Different types of drilled displacement (DD) piles are available in practice. DD piles are classified according to the drilling tool design and installation method. The capacity of a DD pile, depending on its type, is between the capacities of geometrically similar nondisplacement and full-displacement piles installed in the same soil profile. This paper provides an overview of the different types of DD piles and their installation techniques and describes three design methods used in practice. It also compares DD pile capacities obtained with these design methods for two different sites.

Jan 1, 2010

By Roderic A. Ellman

The new Woodrow Wilson Bridge (WWB) will replace the existing bridge over the Potomac River to connect Alexandria, Virginia to Prince Georges County, Maryland. The new WWB will extend approximately 1.1 miles across the river, with a 367-ft long bascule span in the main river channel where the water depth is about 36 ft. The subsurface soil profile consists of up to 50 ft of a soft organic silty clay layer that is very vulnerable to scour, underlain by a deep deposit of hard sandy clay. Foundation construction in the Potomac River required the use of cofferdams to allow structural concrete work to be performed in the dry. This paper will the present the types of cofferdams used to construct the foundations for the WWB replacement project. The bridge is primarily comprised of fixed spans in relatively shallow water and a bascule span over a navigation channel in relatively deep water. Foundation construction included the installation of 48? to 72? open end steel pipe piles and cast-in-place concrete pile caps. To achieve the desired bridge appearance, pile caps were required to extend below the water surface and below the existing river bottom in shallow water locations. Conventional steel sheet pile cofferdams with tremie concrete seal were used to construct fixed span, shallow water piers. Selection of deep water bascule span foundation cofferdams was governed by several factors including contraction scour, environmental considerations and cost. Potomac River cofferdams, i.e., relatively shallow depth cofferdams that are supported by the foundation piling were selected. This cofferdam system provided a shallow profile which minimized contraction scour and the amount of filling in the river. Design issues include load selection and cofferdam stability in very soft alluvial soils. Construction issues include erection sequence, tremie concrete mix design and placement procedures.

Jan 1, 2013

By Tracy Brettmann

A new method for estimating ground vibrations caused by pile driving was developed as a result of a vibration monitoring program performed for a large pile driving project. The method is accurate, rational and theoretically based starting with energy actually transmitted to the pile (not the rated or operating hammer energy). This energy is then assumed to be transmitted to the soil in the form of surface waves that attenuate from both geometric and material damping. The main input parameters for this method include the energy transmitted to the pile and the dynamic properties of the soil (wave velocity, material damping, and unit weight). In this study we concurrently measured both: (1) pile driving of 14-in.-square, 65-ft-long precast concrete piles with a Pile Driving Analyzer?, and (2) vibration levels at various distances away from the piles during driving. A geotechnical study for the site was also performed that included measurement of the dynamic soil properties using both crosshole and seismic cone testing. This paper presents the data obtained from the study and compares the results to the values estimated using this new method. Vibrations from pile driving is a serious matter that impacts virtually every pile driving project. It is important that accurate methods for estimating ground vibrations be available to engineers and contractors.

Jan 1, 1999

By Kazimierz Gwizdala

In the paper the method for estimation of settlement of vertically loaded piles in a group is presented. The method is generally based on the hybrid procedure with non-linear solution for single piles and with interaction between them for the low-strain shear modulus. Some attention is paid to the influence of deformation and strength parameters used in calculations. The applied model is verified in the framework of the research programme carried out recently in the Geotechnical Department of Gdansk Technical University. It concerns monitoring and analysing the settlements of the existing structures on piles. A comparison of calculation and measurements results for two tested buildings is presented as an example.

Jan 1, 2002

By Maral Papazian Bedian

Construction contracts in the USA contain the clause "Value Engineering" ? an interesting and curious clause allowing contractor initiated design changes. Misleading is the interpretation of value engineering implying cost saving and sharing with the owner, and curious is the timing, just before beginning of actual construction. It is not surprising that such a clause would simply be ignored, because it involves change, often major design changes in very short time; and change is feared, moreover, it is vehemently resisted by all parties, owner, designer, contractor. The problem in the USA may lie in the divergence and separation of the two entities: Designer/Engineer and Builder/Contractor, assigned to the "one" engineering project. The priorities and incentives of these two groups are very different. The Engineer spends years, even decades, in design and prepares contract drawings often without a deep understanding of construction methods. Worse, with all the time available to him and in our era of tremendous advances in computational methods and speed, the designer turns in plans that are inexcusably exaggerated code-based design with excessive safety factors. As to the Contractor, he builds, often without appreciation of design principles or regard for design engineers. Redesign to apply a new technology or optimization of an inferior design just before construction becomes unthinkable. It is not surprising that adverse and hostile relationship between the designer and the contractor is a norm with extended disputes and claims, not to mention the cost these entail. Surprisingly, "Value Engineering" was successfully implemented in record speed on several very large projects in the metropolitan New York area. The process of change was unconventional, painful, and even comical. Four case studies are presented: two Design/Build: the 1.2 billion dollars Hudson-Bergen Light Rail Transit System in New Jersey and the 90 million dollars MTA Bus Depot in Manhattan, and two Conventional Design/Bid/Build: the 90 million dollars Queens Boulevard Bridge and the 150 million dollars Long Island Expressway.

Jan 1, 2002

By Gordon Chen

The Block 37 Chicago Transit Authority (CTA) Tunnel Construction Project was originally designed by STV to connect Blue Line subway in North Dearborn Street and Red Line subway in State Street in the downtown Chicago Area. The project was proposed using tunnel mining techniques combined with steel pipe jacking and fiber glass rebar soil reinforcement. Weidlinger Associates, Inc. (WAI) and Kiewit Construction Company proposed an alternate design using open cut construction technology. WAI designed a complex temporary excavation support system using Soldier Pile Tremie Concrete (SPTC) walls and Soldier Pile Lagging walls supported by cross lot/corner bracing elements. Below the top of the existing tunnel, a top-down construction technique was utilized. A steel temporary traffic decking system at top of the excavation site served as the daily street traffic function as well as the first level of bracing for the support of excavation. The project encountered great challenges of soft clay conditions in downtown Chicago, numerous existing utilities in the excavation site and the requirements of protection for a number of historical buildings nearby as well as the protection of the city streets. The construction was successfully completed at both State Street/Washington Street and Dearborn Street/Randolph Street. The monitoring system showed that ground movement and adjacent building settlement was kept to a minimum during construction.

Jan 1, 2009

By J. Allan Tice

In the past fifteen to twenty years, the use of drilled piers to support high capacities in coastal plain deposits has become more and more common. With improved construction techniques and better understanding of pier behavior, drilled shafts with capacities of 200 to 500 tons are not unusual. The purpose of this presentation is to review several drilled pier installations from North Carolina to north-east Florida as a means of illustrating the different types of design concepts and installation techniques which are presently being used. ACKNOWLEDGEMENTS The information in this presentation was obtained from work performed by many individuals and companies. The section on limestone socket caissons in South Carolina is an abridged version of a paper prepared by Rob Smith and Neil Gilbert of Law Engineering's Charlotte, North Carolina office, and is used with permission. The section on pier installation in northeast Florida is an abridged version of a paper prepared by Kirk Mcintosh, Tom McDaniel, and Randy Knott of Law Engineering's Jacksonville, Florida office, reprinted here with permission. Additional data discussed in this presentation has been obtained from Farr Foundation Company, McKinney Drilling Company, and Peterson Drilling Company.

Jan 1, 1988