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By G. G. Goble

Dynamic pile testing is now over 20 years old as a routinely applied tool for evaluating driven pile installation. The first test on a cast-in-place pile was performed more that 15 years ago. The research that produced the method began almost 30 years ago. But, questions still arise regarding the appropriate use of this technique so some review is useful. Today a number of methods including dynamic testing all depending in some way on the application of dynamics are in routine use. First, Wave Equation analysis can be used to predict pile driveability before going to the field. The same approach can be used during driving to estimate the bearing capacity based on the blow count observed in the field. Dynamic measurements, on the other hand, can only be used after pile driving has begun. They offer predictions of pile capacity as well as measurements of hammer, driving system, and pile driving performance characteristics. The first part of this paper will be devoted to discussing how the foundation engineer can use these tools. First, a brief review of what dynamic methods actually do. In Wave Equation analysis a numerical model of the hammer, driving system, pile, and the soil is created by the engineer. The hammer is dropped on the pile and using a discrete, dynamic analysis the motion of the individual pile elements is calculated as a function of time. Of course, input information must be supplied by the program user to describe the hammer, driving system, pile, and soil. In the current state of development, the primary problem in input data is with the hammer performance (efficiency) and the soil description. Research may be able to do a better job with the soil data, but hammer performance will always vary from hammer to hammer and is dependent on the affectiveness of the inspection process. Prior to beginning pile driving the Wave Equation analysis supplies the best available estimate of what will happen when driving begins. It gives an estimate of blow count during driving, driving stresses, both tension and compression in the pile, and for diesel hammers, stroke. The selection of the driving system can be checked with the results of Wave Equation analysis and modifications can be made if required. For example, if the blow count at the required capacity was deemed excessive by the contractor a larger hammer could be tried or if driving stresses were too high changes could be made in the cushion or the hammer selection could be modified. All of these modifications are possible with only the cost of a computer run. The primary questions regarding the accuracy and reliability of Wave Equation analysis at this time is with regard to the assumptions made to represent the soil characteristics and the difficulty in predicting hammer performance.

Jan 1, 1993

By Rüdiger Wunsch

The new high speed Vienna - St.Pölten line and the Lainzer tunnel are to be connected to the existing Western railway line in Vienna. This involves building an underground cut and cover branching tunnel which will be connected to the Western railway line by ramps. A key structure is the Herzmansky Street tunnel, which has a length of some 820m. It is to be constructed as a cut and cover tunnel using the top down method. The walls of the tunnel are designed as a water resistant structure consisting of double walls, an outer wall of bored piles and an inner reinforced concrete wall. The bored pile wall will be used as a temporary retaining wall during the construction phase and will also be a structural part of the per­manent tunnel wall. The retaining walls of the open pit, which will have a depth of up to 14m and a width of 12m, were investigated as a non-contiguous bored pile wall and overlapped bored pile wall. Preventing ground water from penetrating into the pit is of paramount importance. The high ground wa­ter level is the determining factor for the dimensioning of the bored pile wall and results in the require­ment for a water resistant concrete structure. It has been necessary to adopt adequate measures, therefore, in order to reduce the hydrostatic water pressure during the construction phase, assuming economical pile dimensions.

Jan 1, 2000

By Hiren J. Shah

The urban environment and geology create unique challenges for design and construction of deep foundations. The effect of these is prominently experienced in New York City. Three such project case histories are presented in this paper. The first project is a multi-use development. Relatively unusual glacial geology was observed at the site during the subsurface investigation phase. This played an important role in the selection of deep foundations as well as during construction. The design and construction aspects of the pile foundations, settlement estimates, a pile drive test program during design, piling equipment and production pile installation are discussed herein. A relatively smaller project is the second case history. A combination of drilled and driven deep foundations was employed in one area of the project due to its unique conditions. In another area of the project, an addition to a structure required the use of supplemental foundations to resist new additional loading. Tight space and load sharing with the existing foundations were important considerations in the design and construction. Finite element modeling of the existing and completed structure was performed which was an interesting aspect of the project. The third project case history involves a very large multi-billion dollar project in which various different types of deep foundation elements were used. The aspects requiring the use of such a variety of types and sizes of deep foundation elements included: geologic conditions, re-use of existing foundations, protection of adjacent infrastructure, construction staging, restricted space, loads, deep excavations, cost and schedule.

Jan 1, 2011

By Harry Schnabel

A 6200 m² cement deep soil mixed (CDSM) wall was constructed for an addition to the Museum of Fine Arts in Boston, Massachusetts. The addition was located along the east side of the existing museum within an existing courtyard and in the area of a recently demolished structure. The basement for the new addition extended up to 9.1 m below the floor slabs of the adjacent buildings. The adjacent buildings are supported on a variety of foundations including; shallow spread footings on alluvial sand deposits, low capacity piles bearing in the alluvial sands and Boston blue clay, and caissons bearing on the alluvial sands and clay. Groundwater was less than one meter below the top of the CDSM wall. The new addition was founded on shallow foundations in the desiccated crust of the Boston Blue Clay. The CDSM wall was selected as the most economical means to control deep seated ground movements, limit movements of adjacent structures, and inhibit groundwater flow into the excavation. Braces and a continuous wale were used to support the CDSM wall where it was located adjacent to structures. Tiebacks were used where there were no structures. Other geotechnical construction at the site included: ? Jet grouting (JG) to improve the ground and provide an impervious subgrade layer at the west end of the addition, ? Concrete pier underpinning was used to support an existing structure on the west end of the site, and ? A secant pile wall using alternating drilled shafts and jet grout columns was used for earth support and a barrier to groundwater flow to allow for the installation of a storage tank at the south end of the site. Inclinometers, total station surveying, vibrating wire strain gauges on the braces and wales and load cells on the tiebacks were used to monitor performance of the excavation support system. The excavation support system performed better than required limiting lateral movements of the adjacent structures to less than 13 mm and vertical settlement to less than 8 mm. No settlements or movement were detected during the construction of the wall. Lateral movement of the CDSM wall was typically below 15 mm with the maximum movement occurring near subgrade.

Jan 1, 2011

By Paul W. Mayne

Axial pile performance can be rationally evaluated within an elastic continuum framework using field results from seismic piezocone tests (SCPTu). Adopting a versatile Randolph-type elastic pile model, the approach can be applied to either traditional top down loading using an anchored reaction beam or the newer Osterberg cell that simultaneously pushes the base and shaft in opposite directions. The axial load distribution within the shaft is also evaluated. For site-specific data at a given site, the SCPTu is an optimal means for collection of subsurface information because it combines penetrometer readings and downhole geophysics in one sounding. The results obtained are at opposite ends of the stress-strain-strength curves, specifically the peak strength for capacity interpretations and the small-strain stiffness (Emax) for evaluating the initial deformations. Axial pile capacity can be analyzed using both direct and indirect CPT methods. As such, the approach allows for a complete representation of the axial load-displacement-capacity curve for pile response. Case studies are presented for deep foundations situated in stiff clays at two national geotechnical test sites located in Houston and College Station, Texas, using top down loading, as well as a third case study of a drilled shaft in clay till loaded by O-cell in Alberta.

Jan 1, 2009

By R. Lee Wooten, David R. Shields, Darren D. Clark

"Borehole permeability tests that measure flow or head changes in boreholes located within seepage barrier walls are commonly used to estimate the in situ permeabilities of those walls for quality control and assurance. The current state of practice for estimating permeabilities from these barrier wall borehole tests is to use equations published by M. J. Hvorslev in 1951. Hvorslev’s borehole test equations model an infinite stratum of uniform permeability, which is not the actual condition for a test performed in a low permeability barrier wall located within a high permeability stratum. We examine and develop alternative equations based on line source analytical models, which more closely match barrier wall test conditions. We describe how these alternate equations can be used to estimate barrier wall permeabilities from borehole tests and compare the results to those obtained from the Hvorslev models. We also provide recommendations that consider differing upstream and downstream water levels.Barrier Wall Permeability Tests - State Of PracticeThe installation of seepage barrier walls has become more common in a variety of applications ranging from dams and levees to contaminated sites requiring retardation of groundwater flow. The types of seepage barrier walls and installation methods include soil-bentonite, soil-cement-bentonite, concrete, self-hardening slurry, geomembranes, and sheet piles, installed with various soil mixing, slurry-supported trench, and driving methods.Owners and contractors have used a variety of methods to evaluate the permeability of these seepage barriers. The following table lists commonly used quality control/assurance tests for evaluating the permeability of a seepage barrier."

Jan 1, 2016

By Michael W. Neill, O&apos

Drilling slurry has become an effective aid to the construction of drilled shafts in caving and/or waterbearing soils. Historically, drilling slurry made of bentonitic clay and water was first used in the US in water well drilling as early as 1889. In coastal Texas drilled shaft contractors began using slurry, often made of on-site clay mixed with potable water, in the years following World War II, on a relatively routine basis. This type of slurry was used to "process" boreholes, in which the borehole was drilled "in the dry" until water or unstable soil was encountered, after which water and on-site clay were introduced into the borehole and mixed in place with the auger or other drilling tool. Drilling then continued under a slurry consisting of the uncontrolled mixture of clay and water until the excavation had reached a relatively impermeable and cohesive material. At this point, a steel casing was dropped into the hole and sealed into the lower stratum of impermeable geomaterial (soil or rock). The slurry inside the casing was bailed or pumped out, drilling continued to plan depth in the dry, a reinforcing cage was set in the partially cased borehole, concrete was placed and the casing was withdrawn. Some soil-slurry was undoubtedly trapped between the casing and the borehole wall, but the quality of that slurry was usually of no concern, because engineers of the period usually viewed drilled shafts as nothing more than deeply buried footings. Any unejected slurry would only serve to lower side shearing resistance, not yet considered in design, but would have no effect on end bearing. In the 1960 's the effectiveness of soil-slurry came into question because it was often ineffective in maintaining borehole stability at marginal drilling sites and because the economy of using shaft resistance, in addition to end

Jan 1, 1991

By Jacques Moraille

The public is asking for more aesthetic designs if they can be proven cost-effective at providing an appealing element to new dams. Lake Lenexa was designed and built around the idea of providing for basic dam functions such as flood control, enhanced water quality, recreation but also to provide an inviting community focal point for the residents to visit and enjoy; truly interact with the dam. The architecturally unique dam and ?one of a kind? spillway were designed to symbolize the water cycle as water moves from nature into the urban environment and the back to nature. A pedestrian bridge that spans the spillway offers visitors a good view of cascading pools and a fountain. The original Lake Lenexa dam layout incorporated relatively high, cast-in-place concrete retaining walls to form the spillway structure. The Black & Veatch project team performed a Value Engineering (VE) study to determine cost-effective means for implementing architectural features within the spillway, which resulted in innovative uses of construction materials not typically used in dam and reservoir construction. The VE study concluded that mechanically stabilized earth (MSE) retaining walls that are normally used for transportation projects would be a cost-effective alternative to the originally planned cast-in-place wall systems for the main spillway and stilling basins. The Black & Veatch study added value by mixing cement-kiln dust (CKD) with on-site clay soils to produce a stabilized material for use under the spillway. The CKD stabilized material properties include low compressibility, high strength and low permeability, which reduced seepage and uplift pressures under the spillway slabs. The cost savings provided by the VE alternatives reduced total costs and enabled architectural elements. The award winning dam design also used drilled caissons, expanded polystyrene (EPS) block forms, customized steel forms and external concrete vibrators to build the pedestrian bridge and upper spillway structures.

Jan 1, 2009

By Osamu Taki

This paper presents the system, the strength of column, the design concept, and the applications with four case histories from the past project as the general aspect of Geo-Column (trade mark of single soil-cement column by SCC Technology, Inc.). In the system, it shows the installation process and drilling/mixing tool with the mixing process. In the design concept, it shows how to design Geo-Column against the vertical and horizontal load. Finally, it shows the applications with four case histories, (1) building mat foundation, (2) isolated foundation on the pedestrian bridge, (3) bridge spread footing and slope erosion control wall in the channel, and (4) cut-off wall and shoring wall in the underpass roadway to the railroad.

Jan 1, 2000

By Ian Vaz, Takefumi Takuma

"The New Orleans area has been repeatedly flooded by major storms and hurricanes since its French colonial era. After severe flooding in May 1995, the U.S. Congress authorized a massive flood protection project called the Southeast Louisiana Urban Flood Control Program (SELA) in 1996 to improve interior drainage in Orleans, Jefferson, and St. Tammany parishes. However, the project was not fully funded before the landing of Hurricane Katrina in 2005 and Hurricane Rita, which breached many of the area’s levees and flooded 80 percent of the city. Finally, the project was fully funded in 2008 and has been worked on towards its 2017 completion. Another large project simultaneously worked on in the area is the Hurricane and Storm Damage Risk Reduction System (HSDRRS). This system was designed for a 100-year level of flood risk reduction. One particular project within the HSDRRS rendered successful due to an unconventional method of pile driving that was utilized to install sheet piles to reinforce an existing concrete I-wall. This paper will discuss how and why this non-vibratory method of sheet pile installation allowed the project to be successfully completed ahead of schedule.INTRODUCTIONSteel sheet piles were utilized on many of the SELA and HSDRRS projects for permanent cutoff walls under concrete I-walls or T-walls or for temporary earth retaining walls of drainage structures. Although the SELA Project was established in 1996 after severe flooding the year before, hardly any work was done on it until the two catastrophic storms Hurricanes known as Katrina and Rita triggered its revival. These two hurricanes also triggered the HSDRRS soon after the storms’ devastation. The SELA project authorized to improve interior drainage systems while the HSDRRS project was authorized to raise or restore levees and floodwalls mainly along Lake Pontchartrain, the Mississippi River, and Lake Borgne in addition to other areas. Figure 1 shows the SELA Projects that have been completed, are still under construction, or approved for construction. The projects fully highlighted in yellow within the map specified the press-in piling method. These improvements included drainage systems, pump stations, surge walls, and outfall canals as enhanced protection for future storms similar to Hurricane Katrina that caused so much damage by inundating the New Orleans area in August and September 2005 respectively (Facts and Figures, 2012). The completion of these projects were the responsibility of the U.S. Army Corps of Engineers, New Orleans District.Due to the fact that many of the projects were in densely populated areas, the Army Corps of Engineers specified a non-impact, non-vibratory press-in piling method for driving and extracting sheet piles for many of the projects to mitigate noise and vibration impacts. The soft soil conditions in the New Orleans area was also a contributing factor in the Army Corps of Engineers’ decision to specify this piling method due to the risk of settlement for existing historical as well as modern structures. In addition, there were other projects that elected to use the press-in method without any contractual requirements. One of these projects was the Inner Harbor Navigational Canal Reach II Emergency Interim Repair which was part of the HSDRRS project that has been under construction since its authorization in 2005 (Facts and Figures, 2012)."

Jan 1, 2017

By Naim Noori Samie

Lateral force rsistance of piles is analytically investigated by dividing the pile length to 3 segments. The first segment (Zone I) models the load eccentricity with respect to the soil and the pile-deck connection, using a third degree differential equation representing the shear variation along the pile. The soil is assumed to be uniform, homogeneous with an elastic-perfectly plastic behavior. The Top soil layer (Zone II) is assumed to be stressed beyond the elastic limit. A simple 4th degree differential equation represents this zone. The soil resistance is assumed to vary linearly with depth (or surcharge). The pile deformation and soil behavior determines the plastic zone length. In zone III the soil is assumed to behave elastically, hence its resistance is proportional to its deformation. A linear 4th degree differential equation is employed in this zone. The compatibility conditions are satisfied on each boundary. Maximum allowable moment and shear are investigated throughout the pile as the basic limiting criteria on lateral force capacity. In this paper the soil coefficients are taken from a proposal by ref(3), and the results are compared with the soil response as determined by the P-Y method as recommended by ref(2).

Jan 1, 1996

By R. Bellotti

The theory of cavity expansion in an infinite frictional soil mass whose strength is represented by a curved Mohr-Coulomb failure envelope has been used to predict with some confidence the cone resistance of a clean dry sand. Experimental data were obtained from cone penetration and pressuremeter tests on two sands, conducted in a large calibration chamber (CC) under carefully controlled placement and boundary conditions. A plane strain bearing capacity theory was developed, and to convert the results to axi-symmetric conditions, an empirical "shape factor" was used. In the paper, the theoretical background, experimental data, calculation procedure, and the results of the analysis are presented. In general, a reasonable validation of the cavity expansion approach to the bearing capacity of deep foundations has been obtained.

Jan 1, 1987

By Ron Bromenschenkel

The State of California, Department of Transportation is currently retrofitting a major interchange near the San Francisco area. The project is located in a highly traveled area of Oakland with light rail commuter service near many footings. Over 600 micropiles are being used in conjunction with CIDH piles for footing stabilization. A specially designed Soil Nail pile will support footings for a new light rail utility structure. Pile testing features in this contract serve as points of interest for future foundation designs. The presentation focuses on substructure issues of this incterchange retrofit. Both design and construction considerations will be covered. Design Considerations: ? Project Description ? Structure inadequacies ? Design criteria ? Design contraints ? Retrofit strategy ? Consultant analysis ? Pile Designs and Test Sites ? Contract Specifications ? Construction Plan and Cost

Jan 1, 1998

By James J. Tansey

A Deep Foundations Institute meeting with the University of Michigan at Ann Arbor in March of 1984 featured legal rights under Differing Site Conditions. A workshop conducted by the authors and Gerard Ittig, Esq. added to the value of the symposium. This paper will be of interest to your attorneys in any subsurface disputes.

Jan 1, 1985

By Michael H. Wysockey

The load test program for the pile foundation at Soldier Field included static and dynamic load tests at four locations around the site. The dynamic tests were run with no knowledge of the static results, and comparison between the two is very good. It was necessary to use a special testing hammer (not the production hammer) to demonstrate capacity with dynamic testing. Over 90% of the piles were HP14x89 with a design load of 230 tons (18 ksi). The load tests showed a capacity in excess of 590 tons for all tests where sufficient set up time was allowed. The remainder of the piles were mostly HP 12x53 with a design load of 100 tons (13 ksi). The measured capacity of these piles was typically about 250 tons. One experimental HP12×74 pile with a nominal yield of 65 ksi held 730 tons (67 ksi) before failing.

Jan 1, 2002

By A. R. Jambekar

City of Bombay has been developed out of former 7 islands. Landmass of 434 sq.km. of Bombay, started looking inadequate for further growth and expansion of Bombay City. In order to develope twin city of New Bombay, State Government formed fully owned Company "City and Industrial Development Corporation of Maharashtra Limited", (CIDCO) in 1971 and entrusted it with planning and development including social and physical infrastructure of New Bombay.Hence, Trans - Thane Creek area is being planned and developed, to serve as counter-magnet to Bombay. Area of 343 sq.km located on the main land, is fast developing into a satellite community, for India's overcrowded financial capital. Thane Creek, running in almost North-South direction, separates Bombay City from main land and posed a significant barrier, to further expansion of city's sprawling suburbs, until, it was bridged for the first time in 1972. On the basis of traffic study, CIDCO decided to construct an additional road link across Thane creek to cope up with future projected traffic. This bridge will connect Airoli in New Bombay and Eastern Express highway near Mulund. Bridging the vast, exposed tidal Thane Creek, have always posed challenging conditions, during constructions of these bridges. In this paper, case history of deep open foundations provided for Airoli Bridge is presented.

Jan 1, 1996

By Christian Divis

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Jan 1, 2002

By Ali Ameli

Design loads are limited for piles relying upon toe stresses in rock due to uncertainty about the rock quality over the whole pile diameter because of rock mass properties or construction effects. The paper discusses the use of video images to evaluate rock quality at the bottom of piles socketed into graniodorite bedrock in a steel pipe pile project. Skillful interpretation was required to assess the 3D properties of the rock from video images. It is necessary to observe the rock mass characteristics near the project site for better perception of the rock features from the images. Video image interpretation skills were established by the evaluation of the cores drilled under the socket base and the results of pile loading tests. Correlations were found between rock appearance in the images and the rock socket drilling records. Rock socket acceptance criteria were developed through monitoring the drilling operations for the specific site procedures. Video images then served as one of the quality-assurance tools together with probing and pile loading test. Lessons and methods learned from video inspection in this project could be used to evaluate rock quality in similar cases.

Jan 1, 2006

By Rich A. Lamb, Paul J. Axtell, Michael K. Muchard

"Since 2010, the Minnesota Department of Transportation (MnDOT) has performed eight full-scale compressive load tests on large-diameter pipe piles at four different project locations across the state. All of the piles were 42-in diameter, open-ended pipes driven to practical refusal on sedimentary bedrock with D125-32 diesel hammers from three separate manufacturers. The rapid load test method in general accordance with ASTM D7383-10 (Statnamic method) was used along with high-strain dynamic testing and subsequent signal matching. Results of these tests indicate that the axial nominal resistance of these piles in compression is not controlled by geotechnical considerations when driven with an appropriately sized hammer and installation criterion. Rather, the predominantly elastic load-deflection behavior of the piles under compressive load suggests the axial nominal compressive resistance is controlled by the structural capacity of the pile. In all instances, the rapid load tests indicated a nominal resistance exceeding that produced by high-strain dynamic tests due to insufficient hammer energy to fully mobilize resistance. In all cases, the hammers used were able to easily install the piles through the soil overburden. Mobilizing a larger hammer simply to demonstrate high-strain dynamic resistance is not economical or practical. This paper presents the subsurface conditions at each location, the ensuing test results, and the ramifications for future projects in Minnesota utilizing large-diameter open-ended pipe piles.INTRODUCTIONThe Minnesota Department of Transportation (MnDOT) has recently performed eight full-scale compressive load tests on large-diameter pipe piles at four different project locations across the state. The four project locations described in this paper where pile load testing was performed are shown in Figure 1 and exist in the southeastern portion of Minnesota. The projects are all major bridges crossing the Mississippi River in three instances and the St. Croix River just above the Mississippi River in the other instance. The first project is the TH 61 Mississippi River crossing in Hasting, MN where two load tests were conducted. The second is the TH 36 St. Croix River crossing in Stillwater, MN where two load tests were performed. The third project is the I-90 Mississippi River crossing in Dresbach, MN where three load tests were conducted. The final project is the TH 43 Mississippi River crossing in Winona, MN where one load test was performed."

Jan 1, 2017

By Mark H. Balfe

Over the last decade, Fenway Park has undergone annual improvements to modernize the facility for players and fans. These renovations include the Monster Seats, the Right Field Roof expansion, a new pavilion behind home plate, expansion of the Red Sox clubhouse, additional roof seating, and concourse improvements. Retrofitting the historic ballpark to bring it up to current standards required installation of foundations to support the new structural loads for each of the alteration projects. This required evaluation of existing conditions, and in many cases augmentation of the foundations at existing columns to accommodate the structural changes to the park. New foundations, generally consisting of drilled-in micropiles, were installed in numerous configurations and conditions. Since 2003, a total of 215 drilled-in micropiles have been installed to augment various columns around the park. The micropiles range in capacity between 40 and 70 tons and are installed through Fill and Organic Soils and embedded into the dense Glaciofluvial Sand and Gravel layer. Issues and learning related to the foundation augmentation include schedule constraints (work is typically conducted during the off-season and schedule is very aggressive), encountering old/abandoned utilities or foundations, ventilation of equipment, and management of spoils during micropile installation.

Jan 1, 2011