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By K. [Muthukkumaran

An extensive program of laboratory model tests was undertaken to study the effect of slope on p-y curves under passive loading in dry sand. The paper concerns the method developed in a series of laboratory model tests to experimentally determine p-y curves. Bending moment curves are differentiated by using curve fitting method of cubic polynomial function. The study includes effect of slope angle and relative density on bending moment and non-dimensional p-y curves. The non-dimensional p-y curves for piles on sloping ground under passive load are developed modifying API method by including a Reduction Factor (R) using the experimental results.

Jan 1, 2006

By Thomas G. Tavernaro, Jeffrey A. Schaefer

"The $106 million Olmsted Approach Walls Project, completed in the spring of 2004 by Massman Construction Co., Kansas City, MO, is one phase of a new $1.4 billion Corps of Engineers locks and dam facility located at Mile 964 on the Ohio River, approximately 17 miles (27.4 km) upstream of its mouth at the Mississippi River. When completed, the Olmsted Locks and Dam (Figure 1) facility will replace two aging locks and dams (Locks and Dams 52 & 53) built in the 1920’s, and produce an estimated $600 million annual economic benefit to the nation through reduced lockage time and operation and maintenance costs. PROJECT OVERVIEWThe Olmsted Approach Walls Project consisted of “in-the- wet” construction of four fixed nose pier structures, four floating concrete approach walls, one fixed wall and related underwater excavation, grading and stone placement. Over 12,000 tons (11,000 tonnes) of structural steel and pre-cast concrete elements, up to 335 tons (304 tonnes) in weight, were safely erected during the project.To support these massive structures, the Louisville District of the U.S. Army Corps of Engineers teamed with INCA Engineers, Inc., Bellevue, WA to design thirty seven 10’ (3m) diameter shafts (cast-in-place steel-shell piles) capable of maintaining elastic behavior below ground while resisting barge impact loads, extreme head-on collisions from runaway tows, and environmental forces from river current, wind, and seismic events.The shafts (typically 150’ (45.7m) in length) were founded 100’ (30m) into the riverbed through alluvium, a very consolidated fine sand and clay Cretaceous soil, and finally into a hydrothermally altered rock. Thirty seven shafts were installed under open river conditions at the site, a group of four shafts at each nose pier-pylon location (Figure 2), and 21 at the fixed land wall. Due to difficulty in achieving the required casing tip elevation the team developed a design modification that was successfully implemented for 27 of the shafts.Concurrent with the work at Olmsted, eleven pontoon segments for the four floating approach walls were constructed at a graving yard in Paducah, KY, developed by Massman Construction Company specifically for the project. While the pontoon geometry varied, the pontoons averaged 350’ (107m) in length, 40’ (12.2m) in width and weighed 4,500 tons (4,082 tonnes). The longest of the four walls, at 1,700’ (518m) was comprised of five interconnected pontoons."

Jan 1, 2006

By J. C. W. M. de Wit

An excavation, within which a tunnel is sunk as a part of the Centraal Station underground station (platform section) of the Noord/Zuidlijn ('North/South Line'), is to be created beneath the Amsterdam Centraal ('Amsterdam Central') station. The section beneath Amsterdam Centraal Station is characterised by the application of a particular technology in the form of, inter alia, the so-called 'sandwich wall'. This is a composite wall consisting of two rows of Tubex piles with a body of jetgrout columns in-between. This wall acts both as an excavation support wall and also provides vertical bearing. The installation of the wall, including both Tubex piles and jetgrout columns, within these specific conditions (limited height, sensitive historical building), within the design requirements set in terms of construction tolerance and water and soil retention, may be regarded as being a pioneering achievement. The environmental constraints are that the trains should continue to run, the inconvenience to passengers should be kept to a minimum and the historic station should not suffer any damage. Because of the complexity of the working conditions, the project is being overseen by a steering group of experts in the specified construction processes. In order to manage the project risks, jet grouting trials were initially carried out, in order to highlight and control execution problems; the practicability of the design is then tested. Work commenced on the sandwich wall in 2003, when the wooden piles were extracted at the locations where the sandwich wall was to be constructed; in 2004, the steel Tubex piles for the southern wall sections were installed. From May 2005, the construction of the sandwich wall got under way; in addition to the described process supervision, an extensive measuring programme was established, so that the process could be adjusted as necessary and the quality of the finished product determined. This applied to both individual columns and for the end product, the sandwich wall. The measurement results were processed for each column, interpreted and the effect on the work still to be conducted was assessed for each future column. Preventative and corrective measures were, if necessary, taken in order to control or counteract the measured defect. In addition to the process-oriented and qualitative measurements, various independent measurement systems at the station building served as a further control in order to prevent damage to the building.

Jan 1, 2006

By Willie M. NeSmith

Cast-in-place piling are a staple of the deep foundation industry, and are used (in various forms) worldwide. In assessing the application of cast-in-place piles, it is of value to reflect on the development of the various systems, in order to understand how the current processes and equipment came to be. This paper traces the evolution of the cast-in-place industry. Emphasis is on developments in the United States; however, since there has been a substantial fusion of US and European processes, notable European developments are also discussed.

Jan 1, 2006

By H. Boghosian

This paper presents the design and construction of a deep basement in a steeply sloping site in glacial till in Glasgow city centre. Existing foundations, adjacent structures and services, in tandem with asymmetric loading, presented particular challenges in the planning, execution and design of the project. The construction methods and temporary works, analysis by the Finite Element method and monitoring carried out are all described.

Jan 1, 2006

By A. R. Dover

The Richmond San Rafael Bridge (Figure 1) is a 4.3 mile long major toll bridge span across northern San Francisco Bay. Tutor-Saliba/Koch/Tidewater (TSKT) conducted a comprehensive seismic retrofit, which was at the time Caltrans? largest-ever construction contract at $484 million. The robust foundation retrofit design of 11 bridge piers included the installation of 26 new, large diameter (126 to 162 inch OD, wall thickness 1.5 to 2.25 inches) CIDH and CISS piles, with steel pipe piles installed to tip elevations of Elev. ?140 to -220 ft, in water depths up to 70 feet. The open-ended steel pipe piles had initial sections ranging from 71 to 172 feet long, with full lengths that extended to the bay bottom and then through 100 to 130 feet of marine sediments to top of bedrock. The marine soils of most interest consisted mainly of soft to firm Young Bay Mud (YBM), a silty, moderately-sensitive clay common to SF Bay. A key constructability issue was the prediction of pipe piles ?running? under self weight (198 to 625 kips in air) and pile driving hammer weight (IHC S-500 with total assembly weight of 322 kips). The term "pile running" is used to describe the penetration of the pile into the soil due to the self-weight of the pile only. This issue was critical because 1) there was limited head room under the bridge deck, and 2) if piles run too deep, the pile splicing on several piles would be problematic (the lowest desirable pile top elevation after running was +10 ft). While running measurements are sometimes made during marine/nearshore construction, there is little published data on predicted vs. actual running. This paper discusses the running prediction under self weight for 26 piles, and the methodology used in developing the predictions, which ranged from 15 to 94 ft of penetration below mudline. Pile running was recorded and compared with predicted values. The prediction methodology was quite good, and no significant constructability problems were encountered. The authors ?tweaked? the model to provide a slightly improved prediction method. The paper presents the model, predictions, observations, and discusses important lessons learned.

Jan 1, 2006

By Hyun. I. Park

Although numerous investigations have been performed over the years to predict the behavior and bearing capacity of piles, the mechanisms of these behavior and bearing capacity of piles have yet to be entirely understood. Bearing capacity is difficult to predict, because it is affected by many parameters, which have complex relationship with each other. The present paper describes the application of Artificial Neural Network (ANN) in dynamic load tests to predict the resistance of driven piles. The tip, shaft, and total pile resistances can be predicted only for piles with available corresponding measurements of these values. The design methodology composed of ANN and genetic algorithm (GA) is applied to find the optimal neural network model to predict pile resistance. The results of this study indicate that the neural network model serves as a reliable and simple tool for predicting the capacity of driven piles.

Jan 1, 2006

By Ken MacLeod

A development at 83 Queens Road in Melbourne, Australia required construction of a three level basement. The normal geotechnical constraints of excavating adjacent to an existing relatively new building were challenging enough for the complicated soils profile occurring at the site. An additional significant challenge faced by the designers, was the requirement to excavate underneath the entire footprint of an existing heritage listed building, known locally as the Mansion, in the centre of the site. Maintaining the structural integrity of that building was afforded the highest priority during the 10m excavation. This paper describes geotechnical aspects of the analysis, design and construction of the secant retention system adjacent the new building and support of the Mansion enabling the 10m excavation to proceed without causing damage to the structure. The secant wall comprised hard-soft interlocking piles constructed using CFA methods. CFA piles along the length of the Mansion provided short term support, with the building load being transferred to the piles by large steel beams jacked under the building. Survey results confirmed that movements of the retaining wall and also the load bearing piles were minimal and well within design expectations.

Jan 1, 2006

By Erwin Stötzer, Renato Fiorotto, Wolfgang G. Brunner, Manfred Schöpf

"Deep mixing methods can be used economically for the construction of cut-off or excavation support walls where other systems such as traditional soldier beams and lagging walls would yie ld unsatisfactory performance, where the installation of vibrated or driven sheet piles could cause vibration induced settlements and where concrete diaphragm walls would be time consuming and expensive. The new CSM method can largely replace the more conventional single or multiple auger methods of soil mixing or jet grouting. The cutter tool is similar to a cutter used in diaphragm walls or cut-off walls and is operated with a Kelly mounted on a drill rig. With this system much deeper walls can be installed and even hard soil layers can be penetrated. CONVENTIONAL SOIL MIXINGIn 1962 Norman Liver patented an auger-based soil mixing technique that has become the basis for the world's current technology.The deep mixing method (DMM), as it is known today, is an in situ soil treatment and improvement technology where the soil is blended with binders and/or other materials that are introduced in a slurry or dry form.Typically one or more hollow, rotating mixing shafts tipped with some type of cutting tool are mounted vertically to the mast of a base carrier and are driven into the ground by hydraulic or electrically powered rotary heads. The shafts above the cutting tool may be further equipped with discontinuous auger flights and/or mixing paddles. The binder is injected through the hollow shafts to nozzles located near the cutting tool where it is mixed with the ground to form columns of treated soil.Individual column diameters range from 0,6m to 1,5m and may extend to 40 m in depth. They can be arranged individually or in contiguous or secant patterns to produce a wide range of treated soil structures on both land and marine projects. Typical configurations are: Single elements, rows of overlapping (secant) elements, grids, lattices and blocks (Fig. 1 )."

Jan 1, 2005

By Peter Middendorp, Gerald E. H. Verbeek

"This paper will describe a brief history of the method of characteristics as an accurate solution of the wave equation, and the author's experiences with the method of characteristics over a period of 30 years.As a result of the offshore pile driving activities associated with the development of the North Sea oil fields in the 1970's, two Dutch companies initiated extensive research efforts. Heerema started to research the dynamic behavior of soil during driving and HBG (Hollandsche Seton Groep) extended the method of characteristics with a straightforward theoretical solution for the shaft friction along a pile.The research institute TNO started the development of the wave equation program TNOWAVE in the late 1970's based on HBG's friction model extension for the method of characteristics. Today the program has a worldwide application in the field of pile testing. This paper will describe its development and application over time and its relation to today's applications for driveability studies for impact hammers (PDPWAVE) and vibratory hammers (VDPWAVE), signal matching for Dynamic Load Testing (DL TWAVE), Pile Integrity Testing signal matching (SITWAVE), and Statnamic simulation (STNWAVE).The paper will highlight that these developments have been the result of multi-disciplinary and multi-national efforts and encourage geotechnical engineers to seek further developments of the wave equation program in a similar manner. Finally, the paper will indicate some areas where such further developments are required."

Jan 1, 2005

By Robert B. Bittner

The Sutong Bridge across the lower Yangtze River in China will have, when completed, the longest span (1,088 m) and the highest towers (306 m) of any cable stayed span in the world. The foundations for this record setting span will also be record setting. They are located in water depths exceeding 30 m with maximum flows exceeding 3 m/sec. The soil at the site of the main pylons consists of layers of silty sands and silty clays extending to bed rock at 270 m below river elevation. This paper describes the innovative methods used by the team of foundation designers and constructors to support this record setting bridge at this very challenging site. This paper covers three specific topics related to the foundations of the Sutong Bridge: ? Design and construction of the 131 drilled shaft (2.8/2.5 m diameter and 114/117 m long) under each of the two main pylons, ? Design and construction of the scour protection for the two main pylons, ? Construction methods used to construct the waterline pile caps (113.8 m by 48.1 m by 13.3 m deep) under each pylon.

Jan 1, 2005

By Chang-Yu Ou, Shao-Chi Chien, Hsuan-Hsiang Chang

"A field test was performed to investigate the applicability of electroosmosis with the injection of saline solution of Taipei silty clay. The calcium chloride solution and sodium silicate solution were used as the saline solution for the injection in this test. The results of this study indicate that injection using calcium chloride solution and sodium silicate solution during the electroosmosis to increase drained water from cathode and electro-chemical reaction can greatly improve the effect of electroosmosis and shorten the time of treatment. The results of field vane tests showed that the undrained shear strength after treatment increased an average of approximately 120% for a treatment period of 24 days.INTRODUCTIONThe first field application of electroosmosis in soil was demonstrated by Casagrande in 1939. Since then, more complete field applications of electroosmosis such as Bjerrum (1967), Fetzer (1967), and Lo et al. (1991b) have been made.The results of field electroosmotic work for a period of 120 days were presented by Bjerrum et al. ( 1967). The mean undrained shear strength, Su, increased from 18 to about 40 kPa, with a uniform surface settlement of about 0.5 m. Lo et al. (1991b), with a more sophisticated installation and a relatively larger spacing, also had positive results. For a 3 m electrode spacing during the treatment of a period of 33 days, the mean Su increased from 18 to about 25 kPa. Although the effect of the electroosmosis could be applied in the field based on the above examples, the response remained slow. For actual field work, the application of electroosmosis will be limited due to short project schedules and request of the effect of improvement."

Jan 1, 2005

By Alain Pecker

The choice of a design concept for a bridge foundation is guided by various factors; several of these factors are indeed of technical origin, like the environmental conditions in a broad sense, but others non technical factors may also have a profound impact on the final design concept. The foundations solutions adopted for the Rion Antirion bridge are described and an attempt is made to pinpoint the major factors that have guided the final choices. The Rion Antirion bridge is exemplar in that respect: the foundation concept combines the simplicity of capacity design, the conceptual facility of construction and enhances the foundation safety. The design of these foundations was a very challenging task which required full cooperation and close interaction with all the parties involved: concessionaire, contractor, designers and design checker.

Jan 1, 2005

By Silas C. Nichols

FHWA Interest is due to: ? An increase in successful projects in the U.S. private sector and in other countries ? Cost effective and more efficient in many circumstances ? Agency Priorities - FHWA "Vital Few" AASHTO TIG

Jan 1, 2005

By Scott Dodds

"The Oxford Hydroelectric Station was a unique project that incorporated a variety of dam strengthening methods to stabilize the facility in order to meet the standards required by Federal Energy Regulatory Commission (FERC). The dam stability and Probable Maximum Flood (PMF) remediation work consisted of (1) construction of a new emergency spillway; (2) installation of 75 high capacity rock anchors; (3) construction of an anchored concrete powerhouse buttress; (4) construction of cast-in-place and sheetpile flood walls; and (5) design and construction of a permanent soil nail wall. INTRODUCTIONThe Oxford Hydroelectric Station is one of 11 hydroelectric facilities owned and operated by Duke Power along the Catawba/Wateree River. The Catawba River originates in the foothills of the Appalachian Mountains just west of Morganton, North Carolina. The river flows east out of the mountains and, at a point just below the Oxford Dam, the Catawba River turns and heads southeast. The Catawba River continues to flow southeast past Charlotte and into South Carolina where it eventually becomes the Wateree River. The Wateree River eventually flows in to the Atlantic Ocean.Located a few miles east of Hickory, North Carolina, the Oxford Dam and Hydroelectric facility is in the upper reach of the Catawba River. Oxford Dam creates the third impoundment along the river known as Lake Hickory. Lake Hickory is well known locally for providing many outdoor activities such as boating, jet skiing, canoeing and fishing. The dam and powerhouse were put into operation in the spring of 1928.Key features of the dam include a short embankment section on the south end of the structure, a 391-foot (119m) long south bulkhead and powerhouse, 540-foot (165m) long gated spillway section and a 235-foot (71.6m) long north bulkhead. The maximum height of the dam is approximately 100-feet (30m) from the crest to the dam/rock interface. (See Figure 1).The work associated with this project is the result of licensing requirements of the Federal Energy Regulatory Commission (FERC) which mandates that all hydroelectric facilities have the capacity to safely discharge runoff created by a critical rainfall event defined as the probable maximum flood (PMF). Duke Power, a division of Duke Energy (DUKE) submitted an initial PMF report in 1992 which indicated that at the Oxford Dam would be overtopped by approximately 10-feet of water during the modeled PMF event. Given the duration and depth of the overtopping, significant damage to the facility and a possible breach could result. Therefore, modifications to the existing facility were necessary to satisfy the report of the PMF model."

Jan 1, 2005

By Yu Chuang, Zai Jinmin, Liu Songyu

"The piled raft foundation is a geotechnical composite construction method, consisting of three elements, piles, raft and soils, which is applied for the foundation in an increasing number. Differential settlements have numerous negative effects on a superstructure in piled raft foundations. Through the analysis of the production mechanism of differential settlements and differential settlements control measures, a method of adjusting pile configurations is presented to control differential settlements. By comparing the measured data and finite element method analysis of one oil storage piled raft foundation, the new method is verified that the differential settlements can be reduced effectively and the inner forces of foundations are more reasonable with varying length pile configurations. The differential settlements can be minimized or even reduced to zero with right pile length.INTRODUCTIONPiled raft foundations are widely adopted for the prominent advantage of limited settlements and adequate bearing capacities. However, there always exits differential settlements in conventional piled raft foundations. The differential settlement is the main cause that produces additional stresses in the structure. Differential settlements have numerous negative effects on a superstructure as well as on a foundation, and should be restricted to allowable limits. How to control the differential settlement is the key interest.An increasing number of structures are founded on piled rafts. For this reason, design strategies that enable an optimized design have a major importance for safety and economy. An optimized design may be defined as a design achieving maximum economy of the solution, that is minimum cost for the installation of the foundation."

Jan 1, 2005

By Ronnie X. Gu, Xing Zheng, Gem-Yeu Ma

Due to implementation of the rotator construction method from which a smooth shaft was anticipated, a full-scale pile load test (Osterberg Method) was performed at Pier 14 Pile 9 of the main span of the New Benicia-Martinez Bridge to confirm the design parameters of the rock sockets. Two levels of load cells were fabricated in the reinforced cage of the rock socket. Each level consisted of three 670-mm Osterberg load cells with a total testing capacity of more than 50 MN in both directions. In an attempt to separate side friction and end beari ng, a 75 mm thick compressible Styrofoam material was placed at the bottom of the cage. The pile load test was carried out in four stages. The multi-level multi stage pile load test data was interpreted for casing friction, side friction for two rock strata, end bearing, and residual side shear values under repeated loading in opposite directions. The side friction from the casing in soils at Stage 2 is approximately 9 MN. The end bearing at the tip of the rock socket at Stage 3 was calculated to be approximately 17 MN at a displacement of about 75 mm. The residual side shear resistance for the 10 m 50% RQD rock strata was calculated to be 9 MN or approximately 50% of initial values, after being pushed 0.3 mm upward in Stage 1, 71 mm downward in Stage 2, then 55.5 mm upward again in Stage 3, and finally 105.3 mm downward in Stage 4. The test results surprising ly indicate that the side shear resistances from both low RQD intensely weathered rock and higher RQD slightly weathered competent rock are about the same at approximately 19 MN. This pile load test provides very critical information for confirming deep shaft design and analyses.

Jan 1, 2005

By Michael Moran

Typical ACIP Pile Rig [ ] Hollow Stem Auger ? Continuous flight auger ? 3 inch inside diameter pipe ? Auger diameters: 12, 14, 16, 18, 20, 22, 24, 30, and 36 inches ? Auger section lengths: 4, 5, 10, and 20 ft ? Weight ranges from about 70 lbs per ft for 12 inch to 120 lbs per ft for 24 inch and 200 lbs per ft for 36 inch

Jan 1, 2005

By Robb L. Swenson

Construction of foundations for the Skyway Segment of the San Francisco Oakland Bay Bridge required innovative techniques due to the mass of the structures being inserted and the unique subsurface of the Bay. Twenty of the pier structures required large sheet pile cofferdams. Eight other foundations were installed in open water without cofferdams at the deeper part of the Bay. This narrative will present the initial planning, as well as the stages of installation, for each type of foundation. The first section will discuss foundation constructability modifications made during the initial planning phases of the project. Considerable effort was expended by Caltrans, the owner, T.Y. Lin the designer, and KFM (Kiewit/FCI/Manson) the contractor in modifying the design to assure that required tolerance would be maintained during the installation of the foundations. The final section will describe the steps required for installation including: initial access dredging, installation of cofferdams, preparation required to install the footing boxes, footing box installation, foundation support pile installation, and pile to box connections.

Jan 1, 2005

By T. Jason Hardell

The Victory Bridge project was contracted by the New Jersey Department of Transportation. The project included the construction of two 4000-ft precast segmental concrete bridges to replace the existing Victory Bridge that was built in the 1920's. The existing bridge was a swing span bridge that was in desperate need of replacement. The project was considered high priority due to the large maintenance costs to keep the swing span operating over the busy navigational channel. In March of 2003 construction began on the first bridge and by April of 2005 all of the segments were set for the second bridge. On September 5 of 2005 the second bridge was open to traffic. The total cost of the project was $110-million. The two new bridges required the construction of 24-eight foot and 32-six foot diameter-drilled shafts with rock sockets. All of the shafts were constructed in the tidal Raritan River working from barges. What will follow is a description of the construction techniques that were used to build these drilled shafts, the anticipated and unanticipated challenges that were encountered during the project, and the lessons learned.

Jan 1, 2005