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By Q. M. Huang

In 1979 our company undertook the project of infra-structural work of White Swan Lake Hotel, (International class ) Guangzhou. Visit to the site showed that it was situated at the riverside, covering an area of 54,000 M2 with 30,000 M2 of which reclaimed from Pearl River. The material used for reclamation was black sand which was dredged from the nearby riverbed. The sand had the properties of high permeability and very low internal friction. The basement of the building was 6.2 m below ground level and 3 m lower than the riverbed. Apart from the pile foundation, a diaphragm wall was to be constructed prior to the commencement of excavation work for basement. A feasibility study was carried out to determine the method of construction which would maximize utilization of the plants and equipment that were available in the execution of the aforesaid foundation works. This report concerns only the construction of the diaphragm wall and the performance of the plants employed. A detailed delineation of the construction method is herein discussed

Jan 1, 2010

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 Howard A. Perko, M. Mae Benvenga, Heather H. Trantham

Displacement of soil and groundwater during helical pile installation can produce excess pore water pressures (PWP) in fine-grained soils. Pore water pressure reduces effective stress in the soil immediately adjacent to the helical pile shaft and near the helical piles. Previous studies have shown generation of PWP may affect the capacity to torque ratios of the helical bearing elements. Large diameter helical piles that generate much of their torque and capacity from shaft adhesion are affected by PWP and therefore exhibit significant pile "freeze" after installation. Computer modeling is used herein to evaluate PWP immediately adjacent to helical pile shafts during installation in various soil types. The models show the degree and distance from the shaft that is influenced by PWP during installation and the amount of time required for the PWP to dissipate. Pile freeze has been measured on several project sites by re‐torque measurements. These re-torque data are compared with computer modeling and correlations between saturated hydraulic conductivity and dissipation time are presented and discussed. INTRODUCTION Helical piles are full-displacement piles, meaning installation does not produce drill spoil. Soil is displaced laterally as the pile progresses into the ground. This displacement of soil causes an increase in PWP, which reduces adhesion between the pile and the soil. For helical piles with small-diameter shafts, adhesion contributes little to the overall capacity and torque of the pile, so PWP changes are not typically considered in determining pile capacity. In modern construction, the use of larger diameter helical piles has become very common. For large-diameter helical piles, changes in PWP immediately adjacent the shaft can be quite large during installation. Increased pore water pressure and reduced adhesion can have a temporary effect on pile capacity and installation torque.

Jan 1, 2018

By Mohammad Eslami

The Tabriz-Urmiyeh Highway shortens the distance of north-western cities of Iran by about 130 km, resulting in improved access and efficient transit between Iran and Europe through Turkey. The highway crosses the Urmiyeh Lake, an inland lake surrounded by mountains. Due to the circulation of salt-water in the lake and the necessity to continue shipping between adjacent ports, a waterway should be kept open. Consequently, a bridge was built to provide access of marine traffic. A causeway bridge had a length of 1,260 m, comprising of 19 spans. In construction of the bridge, more than 400 piles having a total length of 32 km have been driven. For design of piles different methods have been used such as static analysis, dynamic testing, and correlations to in situ tests, such as cone penetration test (CPT). This paper presents construction of bridge substructure, full-scale piling tests, and methods of analysis used in the evaluation of the deep foundation capacity. The presentation includes an assessment of four current direct CPT and one CPTu methods to calculate the bearing capacity of the piles. It was found that the CPTu and dynamic testing are two suitable tools for rapid and optimum pile design and verification.

Jan 1, 2010

By Arash Maghsoudloo, Asli Can

"Abstract This paper presents a ground improvement implementation case under a raft foundation of a local hospital. The selected ground improvement method is Wet Soil Mixing (WSM) technique. Soil mixing is increasingly applied to environmental applications and ground stabilization in geotechnical projects. In this technique, weak soil is mixed with cementitious slurry to improve the characteristics of the soil. The investigated case is one of the pioneering WSM ground improvement technique implementation cases in Turkey. The soil profile is mainly consisted of low plasticity clay. The effect of ground improvement is verified by a series of laboratory tests and four in-situ pile loading tests. The results of in-situ pile load tests on constructed soilcrete columns showed an acceptable factor of safety for the bearing capacity of the WSM columns. Measured bearing capacities in all four tested columns were nearly 20% higher than calculated values. In addition, a set of samples are obtained from the constructed columns and unconfined compression tests have been conducted. The laboratory test results indicate that the selected cementitious slurry has a sufficient efficiency to form the stabilizing columns.IntroductionIn the construction industry, stabilization of the soft ground by lime or cement stabilization is a widely used technique. In ground improvement systems deep mixing method (DMM) results in the same stabilization in deep portions of the soft soil profile by mixing cementitious slurry by means of mechanical augers. The pioneering cases of modern deep mixing application can be traced back to the year 1970 that was used for the stabilization of marine soils below the water level for the construction of harbor structures (Terashi et al., 1979). Nowadays, DMM is shown to be a proper and efficient method for the foundation of the structures and embankments on land. Some recent studies also reported that reasonable settlement reduction range in the stabilized soils under the foundation of structures (Archeewa et al., 2011). In addition to reduction of the structural settlement under service loads, deep mixing methods are also utilized when there is a concern with contaminated soil and groundwater or groundwater control (Andromalos and Bahner, 2003).Although, the DMM is shown to be a successful method in numerous studies for improvement of a wide range of soil types such as organics, fine-grained, and coarse grained material, it has some limitations (Archeewa et al. 2011, Jameson et al. 2010, Jelisic and Leppanen 2004, Lambrechts and Roy 1997, Meyersohn 2007, Miki and Nozu 2004, Olsson et al. 2008, O’Rourke and McGinn 2004, Stewart et al. 2004, Yang et al. 2011). High soil density and stiffness could damage deep mixing rigs. Engineering properties of the soilcrete columns changes based on the soil type, water content and other factors such as organic content of the available soil profile, so properties of the generated soilcrete should be verified by a set of rigorous testing procedures (Puppala et al. 2004).Based on the general classifications presented in the ground improvement literature, deep soil mixing method is divided into two main types of dry or wet mixing methods. In the dry and mixing methods compressed air and water are utilized as the binder transporter medium respectively (Moseley and Krisch, 2004). In addition, DMM methods can be categorized based on the employed mixing methods during the construction. In this study, the main aim is to present and elaborate on the selected method is known as Wet Speed Soil Mixing (WSSM)."

Jan 1, 2014

By Michael Lane

With the success of their existing casino operation on the Ohio River in Lawrenceburg, Indiana, the Indiana Gaming Co., LP planned a major expansion of the current facilities. This expansion includes a second 1400+/- car parking garage, a new surface parking lot, elevated walkways, and a new floating casino that will double their present square footage and consolidate all of the gaming activity to one floor. In March of 2006 Richard Goettle, Inc. was awarded the general contract to construct a 260? x 520? boat slip for the new Argosy VII floating casino. An Open Cell® bulkhead system was specified as the means for constructing the new slip. Our contract included the purchase and installation of 300,000 square feet of PS27.5 sheet pile, excavation of 230,000 cubic yards of soil, and a 3300 square foot Mechanically Stabilized Earth wall.

Jan 1, 2008

By Steven L. Anderson

A cut-off wall has been designed and is currently under construction along the Back Dam of the existing tailings impoundment at Red Dog Mine, Alaska. The cut-off wall, which will be in the order of 5,000 ft long and up to 150 ft deep, when complete, is being excavated using a 40 metric ton Bauer trench cutter head mounted on a Liebherr crawler crane, in combination with a closed loop slurry pumping and de-sanding system. The tailings impoundment is situated in an area of warm permafrost and high potential seismic activity. Design incorporated an assessment of rock jointing to define the final depth of the wall along the alignment requiring the use of plastic concrete backfill to address the concerns associated with potential cracking of the wall due to settlement and during seismic activity. The results of the geotechnical investigation program, particularly with respect to variation in rock hardness along the wall alignment are discussed, as are the design criteria for the plastic concrete backfill, the challenges faced during construction, including scheduling of the work with the on-going dam raise activities of the mine, and the lessons learned with respect to potential productivities and selection of cutter wheels and teeth. Also described are the requirements for and advantages of utilizing a slurry boosting system to meet pumping requirements, re-design of the plastic concrete mix to consider workability and optimization of cutter teeth configurations to reduce wear through highly varied rock hardness.

Jan 1, 2010

By Richard Crockford

The World Trade Center (WTC) is located on the west side of Manhattan in New York City, approximately 0.5 miles north of Wall Street, and is owned and operated by the Port Authority of New York and New Jersey (PA). As part of the WTC site redevelopment the New York City Transit Authority?s No. 1 subway line which runs through the site below grade, was underpinned so that the soil beneath it could be removed along with the rest of the new east basement excavation. Consequently a scheme comprising micropile installation through and around the existing subway box was designed. The subway had to remain in use throughout save for planned weekend outages to allow a portion of the underpinning to be fitted through or on to the existing structure. At times this involved accessing and drilling from within the subway tunnel under short General Order (GO) Subway shutdown periods. At either end of the subway passage through the WTC site jet grout underpinning was designed to provide support and to complete the excavation and construction of the east basement wall in the areas beneath the subway where it was impossible to install a slurry wall. The jet grout blocks thus formed had to be largely installed around the clock during 53 hour long GO weekend outages and had to overcome severe logistical constraints in and over the tunnel. The jet grout blocks had to provide strengths of at least 500 psi at 3 days and 700 psi at 28 days. The jet grouted soil mass also had to have a level of permeability less than 0.03 feet/day (1 x 10-7 m/s). After an extensive trial program and then production testing it was concluded that the glacial till above the rock proved to be a particularly difficult soil strata to collect test data from and hence the level of observational monitoring was increased to progress the excavation works. Throughout the installation of micropiles and jet grout columns extensive monitoring was in place and prompted a variety of working method changes. The work described in this paper was performed by the Nicholson Construction Company/EE Cruz Joint Venture.

Jan 1, 2008

Since the 1989 Loma Prieta Earthquake in the San Francisco Bay Area, the California Department of Transportation (CALTRANS) has accelerated seismic upgrading of their bridges. Many structures can be improved with the simple addition of hinge seat restrainers. Others require modification of column bents and superstructure to column connections. Often, footing retrofits are necessary, which require the addition of tension/compression elements (compression piling and tiedowns anchors) to resist overturning moments substantially larger than those originally used for footing design. These footing retrofits may include doweled reinforced concrete footing extensions or new pile caps which transmit forces to either driven steel or drilled concrete piles. In some cases, installation of these traditional piling elements is expensive, impractical or impossible due to: low overhead clearance, ground obstructions, high water table, noise or vibration sensitivity, or the inability to laterally expand the existing plan dimensions of the footing. In the latter case, one practical option is to attach small diameter drilled and grouted tension/compression piling elements (Pin Piles) to the existing footing. The footing may be strengthened with dowels and added concrete thickness or there may be a reduced shear span due to the installation of larger or jacketed columns. A reduction of elements is available with a Pin Pile alternative, particularly when the selection of traditional standard piles is governed by the reduced tension/uplift capacity available from the traditional elements, since Pin Piles exhibit superior uplift performance.

Jan 1, 1993

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 S. S. Gajin

The paper deals with parametric vibrations of an axially loaded pile. The dynamic model is derived by means of Hamilton's principle and reduced to a partial differen­tial equation with variable coefficients and corresponding initial boundary conditions, taking into account the influence of the axial force. By means of Galerkin's method, the partial equation is further reduced to a Matheu-Hill's matrix partial differential equation of the second order. Since the problem of the dynamic stabili­ty has been expressed only for standing piles, the paper analyses in detail two stan­ding piles, one which is restreined, whereas the other is hinged at the toe. In both cases it is assumed that head horisontal displacement is prevented. Using Ruunge-Kutt's method, a computer analysis in the time domain is given for the characteristic parameters and possible boundary conditions. The paper analyses the stationariness of the process, as well as the dependance of the critical excitation frequency upon the pile parameters. The results have been illustrated by respective diagrams.

Jan 1, 1989

By Edmund J. Cardoza

WELCOME TO THE DEEP FOUNDATIONS INSTITUTE 26TH ANNUAL CONFERENCE AND WELCOME ESPECIALLY TO THIS SEMINAR ON NON-DESTRUCTIVE TESTING OF DRILLED SHAFTS, PRESENTED BY MEMBERS OF THE DFI DRILLED SHAFT COMMITTEE. MY NAME IS ED CARDOZA; I AM A VICE PRESIDENT WITH THE MILLGARD CORPORATION, A DRILLED SHAFT CONSTRUCTOR FOCUSING PRIMARLY IN THE EASTERN HALF OF THE UNITED STATES.

Jan 1, 2001

By Robert A. Field

Static-Load Piledriving systems utilize hydraulic push to advance piles into the ground. Dynamic systems (ie. hammers and vibratory equipment) utilize impact, or vibration, to advance the piles. Static-Load systems are most commonly utilized in situations where noise or vibration would adversely affect the people, structures or equipment located near the site. Static-Load technology is most advantageous in situations where vibration, noise or access constraints make it difficult, risky or disruptive to utilize conventional piledriving systems.

Jan 1, 1995

This Workshop was held at the Doubletree Inn, Seattle, Washington from September 26 to 28, 1997. Run under the auspices of the Deep Foundations Institute (DFI), it was co-funded by the newly formed Japanese Association of Micropiles (JAMP), and the Federal Highway Administration (FHWA). The Workshop was jointly organized and facilitated by Fujita Research Corporation and ECO Geosystems, Inc., with close support by Donald B. Murphy Contractors, Inc. DFI kindly consented to publish these Proceedings. As is clear from the list of attendees, 42 specially invited engineers from all aspects of micropile technology were present, representing Japanese, European and American practice. This proved to be a most friendly and interactive group of people, who freely exchanged ideas, views and close comradeship, not only during the technical sessions, but (and especially!) during the numerous social events. Perhaps the best illustration of this came in Day 2 when the attendees were divided into five competing teams, each comprising representatives from the different geographic groupings. These teams had to quickly devise solutions to two technical problems (using standard data previously provided. A team of "referees" (who also acted as "coaches") later determined the most apposite response, based on constructability design concept, cost, schedule and so on. Not only were the winning team very liberal in distributing the prize (vintage California champagne) among themselves, but the whole Workshop soon benefited from their generous division of the spoils of victory.

Jan 1, 1997

By E. Mongilardi

The construction of large underground openings through cohesionless or weak cohesive soils and under the water table in particular, often requires a ground improvement to be done from the surface or ahead of the excavation face in tunnelling problems. To this purpose various injection procedures have been used in the past and new outstanding techniques have been developed recently, such as "jet-grouting", extending the feasibility range. The paper presents a review of basic principles and practical design criteria with particular reference to the newest trends of development. Case histories have been selected within the experience of specialist contractor Rodio Co. showing the variety of problems solved by manifold grouting procedures and layouts, in widely different soils ranging from the sandy-gravelly alluvia of Milan to the soft marine clays of Singapore.

Jan 1, 2010

By Frederic Masse

With widespread acceptance in the market place, many engineers are choosing ground improvement techniques to provide suitable foundation subgrade at sites that would have traditionally required deep foundations. This paper discusses the Controlled Modulus Columns (CMC) ground improvement technique and some case histories highlighting the use of this technique for retail development sites. CMC are a sustainable and cost-effective ground improvement technology that transmit load from the foundation to a lower bearing stratum through a composite CMC/soil matrix. The CMC installation is also an attractive option from an environmental perspective because it utilizes reverse flight augers, which displace the soil laterally. This installation technique achieves two goals: it densifies the soil around the CMC, which improves load transfer into the element and avoids spoil and its disposal. Through the introduction of two cases histories, we will present the key benefits of the CMC technology. Each case history will clearly illustrate how a CMC solution can reduce the overall cost of a project when compared to a more traditional type of deep foundations. They will also show how the use of CMCs has benefits that relate to the overall sustainability of the project. While CMCs are an attractive financial and sustainable option, they have also demonstrated that the performance of the system is comparable to that of deep pile foundations. Because CMCs are a relatively new technology many potential users are not aware of its benefits. While we discuss the use of CMCs to support buildings in this paper, CMCs also have been used for a variety of other applications including foundations for tanks, mechanically stabilized earth (MSE) walls, and embankments

Jan 1, 2011

By John E. Lens

Minutes after the Friday afternoon October 16, 2009 announcement that the 80 year old Lake Champlain Bridge was closed to traffic out of concern for public safety, emergency detour planning started at VTrans and NYSDoT. The closure severed a cross-lake link between Addison, VT and Crown Point, NY, which created a 76 mile detour and significant hardship for commuters, farmers working on both sides of Lake Champlain, and businesses relying on both traffic and employees commuting between Vermont and New York. Rehabilitating the bridge was determined to be economically and technically unfeasible and the design of a replacement bridge was accelerated for a spring 2010 construction start. In the meantime, a temporary ferry alternative was to be rushed into service beside the original bridge by February 2, 2010. This paper presents the case history of the fast-tracked ferry dock design and construction on the Vermont side. Twin 300-foot-long pile supported approach spans, a loading slip system and ice deflectors were designed, fabricated and constructed in 90 days in the fall/winter of 2009-2010. This chronicles the project from initial concepts through the extraordinary cooperation between state and federal agencies, and near round-the-clock winter construction on Lake Champlain. This project and its companion project on the New York shore succeeded by virtue of exceptional cooperation between seasoned regulatory, design, and construction participants and warrant this case-history presentation of the Vermont project to share within the industry as an example of overcoming extraordinary challenges.

Jan 1, 2011

By Tom A. Armour

Different variations of soil nailing techniques have been used in the United States since the late 1970's. Such techniques owe their origins to French developments, which began in the early 1970's as a spin-off from European tunneling excavation support practice. The growing demands of urban infrastructure development and rehabilitation and environmental protection have created an active and expanding soil nailing market demand for earth retention and slope stabilization in the United States since its early developmental years. There is a clear need for a fundamental review of the large number of soil nailing techniques that are currently being used in the United States. Following a brief summary tracing the historical development of soil nailing and a generic classification of applications, this paper provides a review of the different recent advances in the design and construction of soil nailed systems. Discussion topics include nail design advances, permanent "top-down", structure support/underpinning, alternative face stability measures, composite systems, hollow bar and fiberglass nails and architectural reinforced concrete/shotcrete facings. Case histories will be presented to illustrate each of these advances.

Jan 1, 2003

By Steven Dapp

A new hyperbolic model for generating P-Y curves is developed for use in lateral analyses of cemented soils (a ?C-F? soil with both cohesive intercept and friction angle), and includes degradation of the static loading soil response to model the effects of load cycling (repeated loading) with load cycle number. The p-y curves, for both static and cyclic loading, were derived from full-scale lateral test results conducted on a set of six drilled shafts in a loess deposit at the Kansas DOT test site. Values of the model parameters obtained from the load testing at this site are presented, as well as a discussion of the model parameters effect on the results such that the model may be rationally applied to other sites with C-F type soils. A step-by-step procedure is presented to illustrate the application of the model. Correlation of the model to the CPT cone tip resistance (qc) from CPT testing is made, as this was found to be the most reliable; However, the model is applicable to other methods, both in-situ and laboratory, of assessing the soils strength.

Jan 1, 2011

By K. Y. C. Chung

A case study on foundation engineering through organic soils is presented. Located along the west shore of the Hudson River, site soils consist of random brick fill over a thick layer of peat and organic silts or clays. The organic layer is underlain by medium dense to dense sand with varying amounts of silt. Strong artesian pressures were measured in the sand. A pile foundation system was selected to support all structures. To avoid periodic flooding, new fill must be placed on the existing fill. Large total and differential settlements will occur due to consolidation and secondary compression of the organic soils. This settlement will reduce the allowable pile capacity due to the large negative skin friction in the organic layer; and will necessitate long-term maintenance of the final grade elevation. Pile load tests were performed to determine the allowable compression and uplift capacities, long-term capacities and pile driving criteria.

Jan 1, 2010