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By Donald Bruce, Mark Harris, Wesley Schmutzler, James Sanders

"This paper evaluates the history, construction and most importantly the performance of two remedial seepage cutoff walls installed in two major dams in the United States. Beaver Dam, on the White River in northwest Arkansas, was completed in 1966 and seepage through the karstic limestone under the embankment was apparent almost immediately upon filling of the reservoir. Several attempts to stop the seepage by grouting were unsuccessful. In 1994 a cutoff wall consisting of secant piles drilled with 32"" diameter down-the-hole hammers to a maximum depth of 185'?was completed and the seepage was reduced to a negligible amount. It has been over 20 years since the completion of the cutoff wall, and all indications are that the cutoff wall is performing as expected. Walter F. George Lock and Dam on the Chattahoochee River near Fort Gaines, Georgia, was completed in 1963 and suffered the same problem as Beaver Dam due to the limestone on which the dam was founded. Cutoff walls were installed in both embankments (1980s) and solved the problem in these areas, but under-seepage at the concrete lock, dam and spillway structures increased to the point that remediation was essential. The cutoff wall had to be installed through 110'?of water and another 100'?into rock upstream of an active dam that continued to generate electricity during the construction of the cutoff wall. A secant pile wall, in combination with a diaphragm wall, was completed in front of these structures in 2004. It has been over 10 years since the completion this cutoff wall and, again, the cutoff wall is performing as expected. The paper describes the construction of these cutoffs, but focuses on the long-term performance in terms of controlling seepage and piezometric levels.BEAVER DAMBeaver Dam is located on the White River, 609 miles above its mouth, in Carroll County, Northwest Arkansas. The construction of the dam and Beaver Reservoir was authorized on September 1954 by the Congressional Flood Control Act for purposes of water supply, flood control and hydroelectric power generation. The dam site was selected in 1957: construction began in November 1960 and was completed in June 1966. (FIG. 1)"

Jan 1, 2017

By David V. Lewin

Heavy structures in central Cleveland, Ohio, are supported on raft foundations, driven piles, or caissons. Settlements can be predicted and structures are designed to accommodate such settlements. On one project the settlements were not provided for in the design of the structure. Soils are sands, silts, and varved clays to shale. A rift in a central area is 600 feet deep. Solutions to problems, and results, are detailed.

Jan 1, 1985

By Matthew E. Meyer

Renovation, rehabilitation, restoration and expansion of existing residential, retail, commercial, hospital facilities and historic structures requires assessment and evaluation of foundation systems of various ages. The concept of demolition and reconstruction in urban areas is often more challenging, costly, and even prohibitive in some cases due to historic regulations. The authors have been involved with numerous projects related to existing foundation assessment and retrofit, including: hotel and hospital expansions, historic Art-Deco hotel renovations and expansions, garage structure expansions, additions to prominent auction houses, casinos, printing facilities; high-rise structure foundation retrofitting; forensic evaluations of existing building and highway structure foundation systems, and marine bulkhead sheeting systems. The use of non-destructive testing techniques, high-strain dynamic load testing, full scale pile cap load testing and 3-D laser scanning technology has proved to be vital in the assessment and evaluation process, as well as design of foundation retrofit alternatives. This paper presents various methods and techniques to facilitate a phased approach for optimization of existing foundations and subsequent re-use of foundation systems. These methods and techniques are illustrated through the author?s experience and selected case histories from projects with varied foundation and geologic conditions.

Jan 1, 2011

By Anthony D. Barley

Over 60,000 multiple anchors have been used internationally since their introduction in the early 1990s, including 1000 in the United States. The multiple anchor system comprises a "multiple" of "unit" anchors installed within a single borehole - each unit anchor being staggered within the borehole length to mobilize its own capacity independently of the other unit anchors. These systems offer higher capacity than conventional anchors with identical bond lengths due to superior load transfer efficiency. The use of higher capacity anchors may allow reduction in the number of anchors required on a project, which results in time and cost benefits to the anchor installer, contractor, and the owner. Fully removable temporary multiple anchors are available, and have been used with consistent success. Three case histories are discussed highlighting the use of these systems

Jan 1, 2002

By C. Vipulanandan

It is critical to monitor the ground conditions during excavation and drilling of boreholes during construction to identify possible changes in the soil and rock formations. Drilled shafts are increasingly used as foundations to support structures, bridges and other facilities in geomaterials such as soft-rocks and hard clays. Locating the bottom of the borehole during construction with the required design strength is critical. Hence developing a simple device that could be easily adapted/used with the drilling tool was of interest in this study. Determining the shear strength of the geomaterial in the borehole and at various elevations including the bottom of the borehole can lead to better quality control of construction by identifying the various layers based on strength. In this study, a down-hole penetrometer (DHP-CIGMAT) was designed, built, calibrated and tested in the field to determine its effectiveness in measuring the strength of soil/soft rock in the boreholes. Based on limited field tests, linear correlations between geomaterial strengths and DHP-CIGMAT deflection have been developed. The DHP-CIGMAT can be used to identify soils and soft rocks.

By Jim Bruce

The Transformation AGO project, constructed between 2005 and 2008, featured a foundation trade contract that included design of pile caps and grade beams and construction of 138 permanent micropiles. The new foundation works were constructed within seven different settings ? each featuring a host of attributes challenging to constructability ? inside and outside the existing Art Gallery of Ontario, all while the gallery remained open for business. Transformation AGO resulted in several firsts for micropiles in the Toronto construction market: this was the first micropile trade contract with a multimillion dollar contract value; it featured the first static compressive load test performed beyond 7000 kN on a single micropile; the first static compressive load test beyond 8000 kN on an experimental pile cap supported by two test micropiles; and it was the first publicly funded project to go to tender with micropiles listed as the preferred foundation option. This paper outlines the successful application of micropiles at the landmark Transformation AGO project.

Jan 1, 2011

By David J. Baxter

Use of bored displacement piles has experienced significant growth in the UK piling market sector, largely due to their environmental advantages over other piling methods and through cost benefits. Bored displacement piles are a cast-in-situ construction which can be formed with minimal production of spoil and offer low noise and vibration compared to driven displacement piles. A large variety of bored displacement piles have been developed. This paper describes a standard system for their classification. The development of the different types is described along with the factors which have led to their increased use. Consideration is given to processes undergone by the soil during pile installation and design approaches for bored displacement piles are compared. Comparisons are made between the different classifications of bored displacement pile. Comments are also made on the installation of such piles. It is concluded that complex changes occur in the stress states of the surrounding soils. Such effect of the pile installation on the soil should be accounted for and there is a need, therefore, to further refine the design process for these piles.

Jan 1, 2006

This work shall consist of furnishing and driving foundation piles of the type and dimensions designated on the plans or in the special provisions including cutting off or building up foundation piles when required. This specification also covers providing test piles and performing loading tests. Piling shall conform to and be installed in accordance with these specifications, and at the location, and to the elevation, penetration and bearing capacity shown on the plans or as directed by the Engineer. Except when test piles are required, the Contractor shall furnish the piles in accordance with the dimensions shown on the plans or special provisions. When test piles are required, the pile lengths shown on the plans are for estimating purposes only and the actual lengths to be furnished for production piles will be determined by the Engineer after the test piles have been driven. The lengths given in the Engineer's order list will include only the lengths anticipated for use in the completed structure. The Contractor shall, with-out added compensation, increase the lengths shown or ordered to provide for fresh heading and for such additional length as may be necessary to suit his method of operation.

Jan 1, 1989

By Peter J. Nicholson

A new method of constructing retaining walls, in-situ, prior to excavation has been developed. This "Vertical Earth Reinforcement Technique" VERT, has been demonstrated at a full scale test wall at the National Geotechnical Experimentation Site at Texas A&M University. This 10 meter high wall, was constructed of elements of soil mixing in an array that forced composite behavior between the soil mixed elements and the in-situ soils. Inclinometers and extensometers were used to verify the performance of the wall. The construction and results of the testing are presented.

Jan 1, 1998

By Michael McVay

The use of augered cast-in-place piles has seen tremendous growth under commerical structures in the past twenty years. Problems with vibration, soil densification and/or heave associated with driven piles do not occur with properly installed augered piles. Augered cast-in-place piles were originally constructed (1950s) with diameters of .31 m (12 in.) and lengths up to 6.1 m (20 ft); however with the advent of better drilling equipment, diameters varying from .41m(16 in.)to .61 m (24 in.) and typical depths ranging from 18.3 m (60 ft) to 24.4 m (80 ft) are achievable. Reinforcement may vary from a single high strength rebar (Grade 60) at the top of the pile to a continuous steel cage depending on loading (compression, tension-uplift, and lateral). Typical axial design loads (compression) for a single augered cast-in-place pile are in the 445 kN (50 tons) to 890 kN (100 tons) range.

Jan 1, 1997

By M. Makarchian

Existing buildings sometimes experience excessive settlement under their design loads, or due to increased foundation loading, if a change of building use is required. One of the oldest and widely numerical study has been carried out of a simple idealised problem of an underpinned rigid circular foundation to better understand the behaviour of pile used for underpinning and load transfer mechanism from an existing foundation to the underpinning piles. The finite element method has been used for this analysis, with the soil treated as a two-phase elasto-plastic material. It is found that the effect of the length of the pile becomes more significant as pile length increases. As would be expected, the earlier the pile is installed, the less is the final settlement.

Jan 1, 1996

By Takefumi Takuma, Masashi Nagano, Christopher DellAringa

Multiple agencies in Southern California are retrofitting and upgrading their levees to catch up with ever-advancing urbanization affecting the requirements for existing channels and levees in this seismically active zone. Pressed-in sheet piles have been specified on some of these projects to minimize noise and vibration problems associated with sheet pile installation. This paper will study three Southern California levee and sewer pipeline retrofit projects that utilized pressed-in sheet piles in hard soil conditions with N-values higher than 50. BACKGROUND Southern California is home to numerous drainage channels fortified with earthen levees. In spite of the region’s semi-arid climate with varying annual precipitation from year to year, winter storms can bring in heavy and continuous rainfall to the area which overwhelms the levees’ capacities at times. Some levees are running through densely populated areas with homes and other sensitive structures such as underground utilities and bridge piers. Conventional sheet pile driving utilizes either percussive or vibratory pile driving methods, both of which generate high levels of noise and vibration, causing nuisance and potential damage to nearby structures. On the other hand, the press-in piling method utilizes a hydraulic force to push piles into the ground, thus practically eliminating the noise and vibration issue. Although there are types of press-in piling systems mounted on tall leaders on large crawler-base machines, they are less frequently used due to its much larger size and more limited drivability than the type discussed hereunder. The other type of press-in machine sits on top of already installed piles and is anchored with its own weight and additional counter weight when starting off as shown in Figure 1. Once the first few piles are pressed in, the equipment grips on top of the installed piles and moves forward on its own as the pile installation progresses. See Figure 2. This method does not use a vibratory or percussive force to install piles.

Jan 1, 2018

By George Piscsalko

"Quality control of drilled shafts and CFA piles is greatly dependent upon the practices of the site personnel. In many applications it is difficult or not possible to fully inspect the shaft prior to concreting, such as when the shaft is drilled under slurry. CFA piles are cast with no ability to inspect the shaft prior to concreting. There are numerous methods currently available to assess the integrity of drilled shafts and CFA piles. This paper will compare evaluations by three existing non-destructive test (NDT) methods with a new method of Thermal Integrity Profiling for assessing integrity in drilled shafts and CFA piles. This Thermal Integrity Profiling method determines the integrity over 100% of the shaft cross section, both inside and outside the reinforcing cage, by measuring the hydration temperature of the concrete along the length of the shaft. These temperature measurements are made typically only 12 to 48 hours after concrete placement, thus accelerating the construction process. Thermal Integrity Profiling will be described in detail and the Thermal Integrity Profile (TIP) results from several shafts with purpose built defects will be discussed along with several case histories from drilled shafts and CFA piles where Thermal Integrity Profiling was used. The case histories will compare TIP with various other NDT tests utilized on these particular piles including comparisons with Low Strain Integrity Testing and Cross Hole Sonic Logging. Test results for the various methods will be discussed and the excavation of the upper portion of one drilled shaft will be shown and discussed. IntroductionDrilled shafts can be a desirable foundation element in many applications due to the large axial and lateral capacities which are attainable for very large drilled shafts. Drilled shafts can be cast in a dry hole which allows for inspection of the hole prior to casting, but the casting process is very difficult to nearly impossible to inspect with any accuracy. Drilled shafts are frequently cast under slurry as a means to stabilize the surrounding soils during the construction process. When casting a drilled shaft under slurry, it is very difficult to accurately inspect the hole prior to casting and it is equally difficult to inspect the shaft during the casting process. CFA piles are another popular choice for their relative ease and speed of installation. The trend has been larger CFA piles carrying greater loads, which makes quality control critical for these piles. Many of the above mentioned processes are blind to inspection and therefore the chances increase for having defects present in the completed elements."

Jan 1, 2014

By A. M. Hanna

This paper presents the experimental investigation on the ultimate skin friction of batter piles. The model piles were pushed in medium dense sand deposits at different inclinations up to 30 with respect to the vertical and tested under axial compression loads. The decrease in the total skin resistance with increasing pile inclination can be explained in terms of the reduction of the ave­rage mobilized angle of friction between the pile shaft and sand. The analysis, which takes into account asymmetrical earth pressure distributions around the pile shaft, showed good agreement with experimental results.

Jan 1, 2010

By W. J. van Niekerk

Ballast Nedam is in Surinam constructing two bridges that will improve communications in the coastal region. The bridges will cross the Coppenam and Surinam rivers and will be founded on open-ended steel piles over 60 meters in length. The majority of piles are inclined and support prefabricated concrete girders forming the roadway. In most locations the stratum is consolidated cohesive layers extending to a depth in excess of 60 meters. For this reason, before pile driving operations commenced, it was decided that a number of test loads would be carried out determine the capacity of the piles. Loading tests were carried out on specially installed piles as well as on piles that would be used as working piles to support the structure. Working piles were dynamically tested using Pile Driving Analysis (PDA) equipment. This decision was based on the inclination of the piles, the cohesive nature of the soil and the increase of strength after the piles are driven. A good insight has been obtained into the real strength of the soil by comparing dynamic and static loading tests on vertical test piles. This made it possible to determine the required length of pile.

Jan 1, 2000

By Robert B. Bittner

Large diameter piles (2 to 3 m diameter, both driven and drilled) are being used more frequently by designers of bridge foundations. The use of these large piles allows the pile cap to be positioned off the bottom but usually still below water. Conventional cofferdams as shown in Figure 1 below are not suited to this type of pile cap. However, float-in cofferdams offer a viable alternative. This paper describes the float-in cofferdam system, its initial development for use on the Bath-Woolwich Bridge in Maine and its most recent application on the new Carquinez Bridge in California.

Jan 1, 2013

By Elizabeth M. Smith

The kcICON design-build project in Kansas City, Missouri includes widening the existing roadway, improving interchanges and grade separation bridges, and replacing the Missouri River Bridge. The Missouri Department of Transportation (MoDOT) typically utilizes steel H-piles and steel pipe piles as driven pile support for bridges. After bidding the kcICON project, the cost of steel rose significantly and the design-build contractor used an innovative approach to reduce foundation costs without significantly affecting the project schedule. The kcICON team conducted a value engineering evaluation of alternative foundation types for use at four grade separation structures. The result of the value engineering evaluation was selection of precast, pre-stressed concrete (PPC) piles as the preferred foundation alternative. Terracon developed a test program to evaluate the performance, capacity, and suitability of PPC piles at the site using a PDA and CAPWAP analyses. This paper presents the value engineering design, rationale for selection of PPC piles, results of the pile test program, and findings during production pile driving. The collaborative approach to the project by MoDOT and the kcICON team, combined with testing and a site-specific design approach, resulted in substantial savings for the design-build contractor.

Jan 1, 2009

By Darrell L. Beddard

Pile driving started October 29, 1993 and was completed on January 27, 1994. Field work included driving piling from ground surface at one site and at or near proposed footing elevations for the remainder. Piles were driven to specified tip elevations or the elevations directed by the Project Manager. In an attempt to address what installation technique(s) performed the best, several methods were used, including varied predrilled depths, open ended piles, closed ended piles, and the use of both impact and vibratory hammers. Piles were driven closed ended where possible to study the feasibility of this option to reduce construction costs associated with pile cleanout. Piles were driven to different depths to measure capacity variations. The 24-inch (610 mm) diameter piling were driven in one piece while the 42-inch (1.07 m) diameter piling was driven in two segments. A total of 79 piles were driven for the four sites, 74 of the 24-inch (610 mm) diameter and 5 of the 42-inch (1.07 m) diameter. Various hammers were used to determine which hammers provided viable solutions to the potential problems anticipated in the design phase. Hammer selection was based on the driveability studies. Equipment included a 175 ton (1.56 MN) crane, support crane for pile stabilization, crane mounted auger drill, offshore leads, Delmag D30-32, D46-32, and D62-22 diesel hammers, an HPSI 2005 single acting hydraulic hammer, a Foster IHC S-90 double acting hydraulic hammer and a Kencho VM2-25000AII vibratory hammer with the weights set to produce 17,500 pound-inch (1.98 kN-m) of eccentric moment.

Jan 1, 1996

By Lu Peiyan

A computation model of soil-pile (wall) interaction under lateral loading is presented in this paper. The model has been applied to some engineering projects, and the comparison between computation result and measured result shows good agreement, so the model is proved to be correct and practical.

Jan 1, 1991

By James J. Cahill

Contractor's working in an urban environment face a multitude of working conditions. There is no typical "Downtown" job site. From afar we just see the skyline, or up close a specific building. This, of course, does not give us a clue as to the site conditions the foundation contractor faced in doing his work. The open, downtown building site is still available on some projects, but they are becoming rare as our cities are becoming more developed. A typical site today might include any one or several of the following problems: A. Deep pit with no ramp access B. Multi-type known or unknown obstructions C. Height limitations D. Load restrictions E. Existing adjacent building founded on shallow foundation F. Existing foundations G. Existing tunnels, utilities or subways

Jan 1, 1991