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By F. Keith Jacobson

To be involved in the construction of a deep dredged caisson for a major bridge pier is one of the most rewarding and professionally challenging experiences one can have in the bridge construction business. That experience was doubled in the construction of the two deep dredged caissons for the Highway 82 Bridge over the Mississippi River near Greenville, Mississippi. The challenges and the construction risks associated with constructing these two dredged caisson pier foundations highlight the construction engineering innovation associated with major bridge pier construction. The 1,378-foot Main Span of the Highway 82 Bridge makes it the longest cable stayed bridge span over the inland rivers of the United States. The main piers for this bridge are supported on two dredged caissons measuring 80-feet by 122-feet in plan, founding 200-feet and 170-feet below the river surface. The challenges of constructing these caisson structures, sinking them through 70-feet of water to the river bottom and then excavating and further sinking them to the founding grade without exceeding the design tolerances, were enormous. The construction engineering opportunities for innovation included major breakwater structures to create a friendly environment in 11 ft/sec currents, the first time use of Articulated Concrete Mattresses for river bottom scour control, unique air dome design to maximize the buoyancy of the caisson structure while floating, a caisson guide system to assure positive control and positioning of the caisson during the initial sinking phases, and a comprehensive sinking plan to assure maximum control and minimum risk. Many of the innovative solutions to the construction challenges on this bridge will be incorporated into future caisson construction projects on the lower Mississippi River.

Jan 1, 2013

By Anand J. Puppala

This paper provides information on various evaluation studies conducted to assess the CPT based interpretation methods. Salient findings from these evaluations are summarized. Additionally, a comprehensive evaluation study on both LCPC and European methods was performed on twenty-four driven piles selected from four different states. This evaluation showed that the LCPC method predictions are close to measured pile capacities. The European method provided good predictions for driven steel piles. Overall, both methods' predictions show high values of coefficients of variations, which are in agreement with other studies. Overestimation of driven concrete pile capacities is attributed to large estimations of unit point resistance. Suggestions to consider appropriate CPT based pile capacity interpretation methods are presented.

Jan 1, 2002

By Willie M. NeSmith

In the Metropolitan Atlanta Area today, augered, cast-in-place (ACIP) piles will be considered on most projects where deep foundation support is required. ACIP piles were first used in Atlanta in the late 1960s, and application began to blossom in the mid-1980s. Current design practice for ACIP piles is addressed in another paper in this conference. This paper describes the evolution of the ACIP industry in Atlanta, and details the use of ACIP piles on major projects in the Atlanta area.

Jan 1, 2003

By Subrata Ray

A large no of power stations are being set up in Chandrapur area having coal deposits. Several industries are also coning up in this area. The subsurface is geologically formed under Gondwana system and consists of shale strata at depths ranging from 8 to 12 m. The stress deformation characteristics of shale exhibits wide variation because of it's geological origin. In view of this, a study was conducted on bored cast in-situ piles installed for a Switch yard project to evaluate load settlement characteristics of three test piles to understand the probable engineering behaviour of the material at the tip and the sides. An approach is developed to simulate the load settlement behaviour as observed in the field, theoretically. This is based on the concept of load transfer. The fit is obtained by varying the parameters, thus may be considered as iterative in nature. The theoretical curves closely matched the observed curves. The results of this study are presented in this paper.

Jan 1, 1996

By T. Matsui

Many existing bridge abutments on the soft ground laterally move and their many damage examples have been reported. An essential cause for the troubles of the lateral movements may be the lack of examinations for the lateral earth pressure acting on its foundation piles. In the present paper, actual movement condition of existing bridge abutments is first summarized, and then the author establishes a practical and systematical design method for bridge abutment foundation piles, including the examination for the passive pile.

Jan 1, 2010

By Hubert Law, Amin Rahmani

This paper evaluates the effects of pile diameter on the initial modulus of subgrade reaction and proposes modifications to the subgrade reaction moduli that are commonly used in the current state of practice based on American Petroleum Institute (API) guidelines. Three-dimensional continuum finite element model of a soil-pile system is simulated under monotonic lateral loadings to develop benchmark data. The benchmark data, which includes small (0.5 ft) to large (10 ft) diameter pile responses, is used to estimate the initial modulus of subgrade reaction for each of the considered pile sizes. The study shows that the subgrade reaction moduli provided by API may underestimate the actual soil stiffness at the soil-pile interface for large diameter piles and may overestimate it for piles smaller than a certain diameter. A simple equation is proposed herein to adequately estimate the initial modulus of subgrade reaction for all pile diameter ranges. The proposed equation is validated by the measurements of full-scale field tests.

By H. S. Radhakrishna

Foundations supporting power transmission and communications towers are subjected to both compression and uplift loads, often of a cyclic nature. Some novel foundations, combining the beneficial features of grouted and helix anchors with that of compression piles and grillages, were developed by Ontario Hydro during the construction of high voltage transmission lines in Ontario, Canada. In addition to meeting the load requirements, the foundations permit easy installation in swampy areas and also minimize impact on environmentally sensitive terrain. This paper describes the features of these composite foundations and outlines the performance criteria used for their design and installation on the basis of load test results.

Jan 1, 2010

4.5.1 General The provisions of the article shall apply to the design of axially and laterally loaded driven piles in soil or extending through soil to rock. 4.5.1.1 APPLICATION (Revised Article 4.3.1.1) Piling may be considered when footings cannot be founded on rock, or on granular or stiff cohesive soils within a reasonable depth. At loca-tions where soil conditions would normally permit the use of spread footings but the potential for scour exists, piles may be used as a protection against scour. Piles may also be used where an unacceptable amount of settlement of spread footings may occur. 4.5.1.2 MATERIALS Piles may be structural steel sections, steel pipe, precast concrete, cast-in-place concrete, prestressed concrete, timber, or a combination of materials. In every case, materials shall be supplied in accordance with the provisions of this Article.

Jan 1, 1989

By Darrell L. Beddard

The test program information provided for some immediate changes on the upcoming contracts and in contract administration for the I-880 Replacement Project. Plan sheet modifications included changes to the pile data tables showing the actual demand load required for structural stability. The normal class of pile with a minimum load carrying capacity was removed. This provided for substantial pile length reduction at several locations since the structural loading was much less than the predetermined pile class ultimate capacity. New specifications were developed and standard specifications were modified to accommodate the newer foundations, installation procedures and pile acceptance criteria. Current Caltrans specifications require that the Contractor provide bearing capacity at the specified tip elevation. This requirement was removed and pile acceptance was determined by the Engineer. Acceptance criteria was established by the State and was based on. set-up trend over time. Static loading tests were reduced especially in areas where testing was performed on the indicator program. Testing procedures were modified and set-up periods were established before piles could be tested. For the contract near the San Francisco Oakland Bay Bridge (Unit E) the FHWA 1000 tons (8.9 MN) test beam configuration was completely changed. This provided added safety and allowed more tolerance in the pile placement for the testing operations. Indicator piles were added as companion piles to the static loading test piles. These piles were used for restrike events which included collecting dynamic data for calibrating the wave equation analysis with static load test results. Indicator piles also provided quick access for restrike events, where as, the static loading test pile needed modification to perform the restrike operation. Penetration rates were recorded for these operations. Wave equation Analysis Program (WEAP) was used in developing the acceptance criteria. The standard Engineering News Record (ENR) formula in the current Caltrans' Standard Specifications was removed for the contracts. Contractors were required to submit, prior to driving piles, a driveability study for their contract. These studies required discussion of their operations, method of installation, effects of soil set-up, set periods, hammer settings, bearing graphs, inputs to the WEAP program and complete a "Pile and Driving Equipment Data" form. Dynamic monitoring was detailed in the specifications on how the monitoring process was to occur. Set periods were established and restrike events were called out with the frequency of these events.

Jan 1, 1996

By J. W. Slatter

Cast in situ screw piling techniques (both displacement and non displacement) have seen considerable growth in recent years due to competitive production rates, low noise and vibration free installation. However the discussion on the mechanics of auger installation, which has implications on the installation effects and installation forces of screw piling augers, has been almost exclusively targeted towards non displacement techniques and in particular continuous flight augers (CFA). This paper discusses the historical development of the understanding of screw piling auger mechanics in sands and presents a new theoretical model to predict the soil transport and displacement characteristics of both displacement and non displacement augers with variable geometry.

Jan 1, 2000

By Jorj O. Osterberg

This paper is for presentation at the 14th Annual Members Conference of the Deep Foundations Institute held at the Hyatt Regency Hotel, Baltimore Maryland on October 10, 1989. This is an introductory presentation of a one hour symposium on the applications of a new testing device. This paper discusses how the device works and its uses. Papers following this describe: - How the cell is constructed and calibrated - Two projects on which the device was used on long driven piles to determine the frictional capacity - A bridge project on which the device was used on an instrumented test drilled shaft and a working drilled shaft

Jan 1, 1989

By Kyle A. Kershaw

The City of Grand Forks, North Dakota obtains drinking water from both the Red River and Red Lake River through a system of raw water intakes, shallow pipelines, and pump stations. However, during flood events, the City often loses access to the system, as evidenced during the record flood event in 1997. As a result, the City decided to construct a new gravity raw water intake system, including a pump station at the base of a 65-foot-deep, 60-foot-diameter caisson, behind a new levee system. Because of high design flood elevations and connectivity of river head to underlying soils, uplift resistance was required for the caisson. A total of 37, 2-foot-diameter, augered cast-in-place (ACIP) piles were chosen to provide uplift resistance. Because of the difficulties associated with installation of piles within the confined space of the constructed caisson and basal stability concerns, installation was completed from the existing ground surface to a depth of 120 feet. Several design and construction issues arose, including squeezing ground during pile installation, placement of long reinforcing bars, and installation of a dual material pile. A dual material pile was required to ensure that the ACIP pile below the base of the caisson was structurally sound and the pile above the base of the caisson could be easily excavated during sinking of the caisson. This paper discusses the solutions to each of these issues, as well as construction sequencing, load testing and integrity testing of the ACIP piles, and the successful completion of the project.

Jan 1, 2003

By Ronald E. Walkington

The U.S. Department of Energy (DOE) is building the world's newest accelerator-based, pulsed-neutron system, called Spallation Neutron Source (SNS). The facility, located in Oak Ridge, Tennessee, is a partnership of six DOE national laboratories - Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos, and Oak Ridge. Oak Ridge has the responsibility for managing the partnership and ultimately operating SNS. SNS will provide opportunities for up to 2,000 researchers each year from universities, national laboratories and industry from around the world for basic and applied research and technology development in the fields of materials science, magnetic materials, polymers and complex fluids, chemistry and biology. When completed, this state-of-the-art research facility will provide neutron beams that are 12 times more intense than any other such source in the world. Most of the world's neutron sources were built decades ago. Therefore, it is easy to understand how SNS will provide new research opportunities unavailable elsewhere, and at the same time restore United States leadership in neutron sciences. Neutron scattering research provides valuable information about materials that cannot be obtained through microscopy, X-rays, spectroscopes, or other techniques. The information gained from neutron scattering research leads to improved materials that are used in high-temperature superconductors, powerful lightweight magnets, aluminum bridge decks, jet aircraft, compact and computer discs, magnetic recording tapes, shatter-proof windshields, and many other applications. SNS is like a flashing strobe light providing high-speed illumination of an object and will record the structure of physical and biological materials from plastics to proteins. Because neutrons have no charge, they can penetrate more deeply into materials than do X-rays, light, or electrons and thus reveal bulk structure and properties of materials. SNS will help to understand and "engineer" better materials and the manufacture of better products at the atomic level. Our high-technology society demands new materials that are stronger, lighter, and cheaper yet perform well under severe conditions. SNS, which is designed with the future in mind, will be the leading neutron research facility for many years to come.

Jan 1, 2001

By Timothy C. Siegel, Paul J. Axtell

The Missouri Department of Transportation (MoDOT) recently replaced the Hurricane Deck Bridge that carries Highway 5 traffic across the Osage Arm of the Lake of the Ozarks in Camden County, Missouri. The former bridge was constructed in the 1920's and was supported on pneumatic caissons bearing on dolostone bedrock. The replacement structure is founded on drilled shafts socketed into the bedrock. During the design phase of this bid-build project, a baseline design was developed and Alternative Technical Concepts (ATC's) were allowed from approved contractors. Those ATC's were confidential and not shared between teams. Either the baseline design or the approved ATC design could be bid by the respective contractors. The baseline design included re-use of the 90-year old caisson foundations. Accordingly, an extensive evaluation of the caissons and underlying bedrock were conducted by coring, laboratory testing, acoustic tele-viewer (ATV), and cross-hole sonic logging (CSL) methods. The results of the investigation indicated the caissons were in excellent condition and suitable for re-use. However, a more cost-effective ATC was submitted, awarded, and constructed that did not re-use the existing caisson foundations but rather reduced the span lengths, increased the number of piers in the water, and supported those piers on drilled shafts. Interestingly, the difference in low bid price between the awarded ATC and the baseline design was less than one percent of the construction cost. This paper describes the multiple foundation designs that were necessary for this interesting project. The various foundation evaluations include the existing pneumatic caissons, large-diameter open-ended pipe piles to support the baseline design, and the design of rock-socketed drilled shafts that were successfully constructed in 2012.

Jan 1, 2017

By Mai Yuanjian

The stabilization effect in large excavation slope with vacuum wellpoints system during construction of a dry dock located in Guangzhou is introduced in this paper. In-situ observations indicate that the effect of wellpoints for decreasing seepage in slope is remarkable even though the muddy sitty clay in it has poor permeability and the slope can remain its stability well. Meanwhile, a non-linear partial defferential equation has been set up to the whole unsteady seepage process as water level in the foundation pit excavated under water goes down to the bottom and so does the seepage in slope due to dewater by vacuum wellpoints system at the same time. And the finite-defference method has been used to solve the equation mentioned above, which differes from conventional wqy where the equation will be linearized firstly. Since the water heads in slope with wellpoints dewatering are more variable, it is necessary to keep non-linear. The calculation results are in good accordance with observation. Vacuum wellpoinnts for slope stabilization in this work is successful.

Jan 1, 1991

By Jeffrey A. Gebhard

As part of the design and construction of the new St. Anthony Falls I-35W Bridge, a full-scale load test was conducted on a 6 1/2-foot diameter drilled shaft in the St. Peter Sandstone. This load test helped identify shaft-rock interaction properties, including end bearing and multiple zones of differing shaft resistance for design of the drilled shafts beneath the three piers adjacent the river. The load test was designed by Load Test, Inc., Braun Intertec and the design team of Figg Bridge Engineers/TKDA and constructed by Design Build Consortium of Flatiron/Manson. Oversight was provided by the Minnesota Department of Transportation. Based on these test results, the drilled shafts supporting the St. Anthony Falls I-35W Bridge were designed to reduce risk and maximize economy for the people of the State of Minnesota.

Jan 1, 2009

By Anne Lemnitzer

Experimental data are the cornerstone of scientific research, providing empirical evidence to validate hypotheses, test theories, inform decision-making and help develop innovative design and analysis methods. However, beyond traditional empirical validations, experimental data have also become the most crucial component of AI algorithms, measuring the algorithms' effectiveness, and allowing engineers to ensure their reliability and applicability. The DFI "Rock Socket Project," awarded in the spring of 2018 allowed for the indispensable, experimental data-based validation of structural shear magnitudes, which have been hypothesized and discussed for years within the deep foundations community and cautiously approached by many design engineers. The fundamental project idea, i.e., the investi- gation of pile shear magnitudes through experimental research, was sparked during a heated discussion in the October 2016 Drilled Shaft Committee meeting in New York. Should we design for amplified shear at the rock socket of a drilled shaft or is this merely an artifact of the p-y design approach? Data were needed to provide consensus.

Nov 1, 2023

By Bryan C. Field

The proposed construction schedule for the St. Anthony Falls I-35W Bride challenged the abilities of the design-build teams to utilize the best and most efficient methods to meet Minnesota Department of Transportation?s deadlines and design requirements to restore traffic to the Interstate 35W crossing of the Mississippi River, along with a sense of normalcy, following the bridge collapse. The project team ultimately designed and constructed two foundation systems at various substructures for bridge support. Steel H-section piles were driven to bedrock for south bridge abutment support and drilled shafts were used for the north bridge abutment and piers for the Mississippi River Bridge. Drilled shafts we also used for the abutments for the three single span bridges carrying I-35W over 2nd Street. The design-build team used high-strain dynamic pile testing with a Pile Driving Analyzer (PDA) to verify H-Pile capacities and performed drilled shaft inspection on a 24-hour basis during installation over the winter months. The drilled shaft inspection process was a vital part of the project quality control program to maintain the necessary methods for proper drilled shaft installation. Ultimately, with an efficient design, quality construction methods and operation, and a rigorous inspection and quality control plan; the I-35W Bridge was opened to traffic 3 months ahead of the already accelerated schedule.

Jan 1, 2009

By Ameir Altaee

Unconventional means and methods were utilized to install over 650 contractor-designed micro-piles for the replacement of the Bronx approach to the Bronx-Whitestone Bridge in New York City. The method utilized reverse circulation (RC) drill rods and down-hole-hammers (DHH) along with grouting through the DHH bit. The overall construction sequence of drill-down, grout-up, place reinforcing is similar to auger-grout piling. The extremely tough drilling conditions required the use of a percussive DHH. The piling subcontractor refers to this pile as a hammer-grout pile. Project background, constraints and subsurface conditions are given. The proposed means and methods as well as the collaboration between stakeholders are detailed. Results of load testing and production installation are summarized.

Jan 1, 2010

By A. A. Gupte

Auger piling system which was developed in the United States in the 1940's is gaining acceptance in many parts of the world. Although primarily used to support foundations, the system is very useful for many other applications such as soil anchors, temporary and permanent earth retention systems, restricted headroom piling and underpinning of existing foundations. In this paper, review of current construction design techniques for the Auger piling system for earth retention and underpinning of structures is presented.

Jan 1, 1989