Search Documents

By Frank J. Arland

Augered-Cast-in-Place piles have been used successfully for many deep foundation applications. The four case studies discussed herein describe ACIP pile projects where problems developed during ACIP pile installation requiring changes to the method or sequence of installation. The case studies illustrate the importance of understanding existing subsurface conditions and project constraints when considering the use of this pile type. Ground loosening and over-excavation of soil during the augering process, a significant concern for fine to medium sands and non-plastic silts below the water table, can significantly impact adjacent structures. This risk needs to be evaluated during the pile selection process and generally can be mitigated, but not eliminated, by requiring the use of piling equipment with high torque and slow auger rotation speed to advance the auger with minimum amount of rotation. In some applications where high lateral stresses in the soil are present such as at the base of retaining structures, the use of ACIP piles may not be appropriate if structure movement is unacceptable. On the other hand, ACIP piles have been successfully used to support deep foundations in preconsolidated varved deposits where the new structure was designed to accommodate recompression settlement.

Jan 1, 2004

By Bernard H. Hertlein

All methods of deep foundation construction present challenges to the contractor and engineer that vary according to the method employed, and the geotechnical conditions in which it is being used. Augered-Cast-In-Place (ACIP) piles are generally regarded as one of the most challenging, because the construction method precludes the use of traditional shaft inspection and quality control techniques. Application of Nondestructive Test (NDT) methods can provide quality control for ACIP shafts that traditional methods cannot, but each NDT method has limitations. These make some NDT methods unsuitable for use on ACIP shafts, and may limit the effectiveness of others, depending on geotechnical conditions. To help contractors and engineers working with ACIP piles select the test method most appropriate to specific site conditions, this paper presents a summary of the major NDT methods currently available, and reviews their capabilities with respect to the unique conditions presented by ACIP pile construction. Case histories illustrate how a combination of careful method selection, skilled data interpretation, and experienced engineering judgment have resolved problems and ensured quality in foundation construction by discriminating between potentially serious defects, and those that are unlikely to be significant.

Jan 1, 1997

By Walter Ensinger

Special foundation works is one of the most innovative sectors in civil engineering and construction. Both engineering techniques and construction machinery are undergoing continu­ous further development. These developments are providing ways to meeting the world-wide requirement for special geotechnical works even faster, even better and more efficiently. Unfortunately, accident prevention organisations have had to realise that the figures on in­dustrial accidents in special foundation works are still above average in number. The Safety & Environmental Working Group of the EFFC thereupon started to carry out a survey on acci­dents occurring in this sector and used this information as a basis for the preparation of acci­dent statistics and an accident analysis. The objective of this undertaking is to determine key accident occurrences and their causes and to consequently determine measures for improved health and industrial safety.

Jan 1, 2002

By David E. Thompson

This paper describes the full-scale field load testing of three deep foundation units using the Osterberg Load Cell. The load tests were completed on three separate projects, two in Massachusetts and one in New York. The Massachusetts projects involved the load testing of two 18-inch O.D. concrete-filled steel pipe piles over water for railroad bridge reconstruction projects in Revere and Saugus/Lynn. The New York project involved the load testing of a 24-inch diameter drilled shaft socketed into sandstone on land for a building foundation in Rochester. The 18-inch O.D. piles were loaded to failure at jack pressures of 142 to 215 tons. The drilled shaft was loaded to failure at jack pressures of approximately 450 tons. The loading testing procedure is described and the results of the three tests are presented. The advantages and disadvantages of the Osterberg load cell for load testing of deep foundations are discussed.

Jan 1, 1989

By Bruno Gemmi

The objective of the ? 200 million ($280 million) project Parma Railways Station-Urban Transformation was the reconnection of the North and South parts of the town by constructing an 80 m (250 ft) wide sunken artery passing under the four double railway tracks of the station without any impact on train traffic. The site of the project, adjacent to the Parma River, presented water seepage problems at any excavation depth. The use of conventional large diameter bored pile machinery was not allowed by the Railway Authority because equipment dimension and construction phases do not comply with train traffic safety regulations. Foundations for the bypass were thus constructed by minipiles nested into jet-grouted soil using machinery operating within the existing head room and at a safe distance from the tracks. Jet-grouting treatment reached depths of 25 to 28 m (80 to 90 ft) from tracks? grade and embedded minipile-heads were terminated at 2 to 3 m (6.6 to 10 ft) below grade. Load tests on minipiles were pushed to failure. Failure occurred at a 240 t (265 t) load without breakage of the bond between the jet grouted soil and the minipiles. A 0.93 MPa (135 psi) shear resistance ??? between minipile steel casing and the jet grouted soil was measured prior to the failure of the steel casings. Overall measured foundation settlements were well within expected values and were considered insignificant.

Jan 1, 2011

By Junhwan Lee

Pipe piles can be either closed- or open-ended piles. Pile load capacity for a closed-ended pile consists of the shaft and base resistances, while, for an open-ended pile, it consists of shaft, soil plug, and annulus resistances. In order to investigate the pile load capacity of both closed- and open-ended piles, two field pile load tests were performed. For the open-ended pile, the fully instrumented double-walled system was used to separately measure all the components of the pile load capacity. The soils at the test site were predominantly granular soils with relative densities varying from loose to dense with increasing depth. The incremental filling ratio (IFR), which affects significantly the load capacity of open-ended piles, was also measured during pile driving. The test results indicated that the total load capacity of the closed-ended pile was higher that that of the open-ended pile, mostly due to the difference in shaft capacity. The shaft and base load capacities of the open-ended pile were 44% and 20% lower than the corresponding values for the closed-ended pile.

Jan 1, 2003

Jan 1, 1988

By Joseph C. Gillen

This paper discusses the design, construction, and performance of the support of excavation system used at The Atlantic Building jobsite. The support of excavation system had to be adaptable to the different conditions surrounding the site. These conditions included support of four historic building façades, including the nine-story Atlantic Building, as well as support of three historic row-houses along two walls. Directly adjacent to the site is the historic Ford?s Theatre and townhouse. Across a 15? alley is the American Immigration Lawyers Association (AILA) Building, and across a 30? alley is the Federal Election Commission Building and another ongoing excavation. Of historical note, these two alleys were the escape route for John Wilkes Booth following his assassination of President Lincoln. With the excavation being 53? to 58? deep, the system included driven and drilled soldier piles, drilled bracket piles, and two modified tangent walls. The bracing included tiebacks, corner braces, wales, cross lot struts, and a specially designed support system for the nine-story façade. The footprint of the excavation included 12 corners and all alleys and streets were to remain open during construction. The performance requirements for system movement at Ford?s Theatre and AILA Building were ½ inches in the horizontal direction. The modified tangent walls were used in these areas to provide stiffness. The soil conditions at the site were fill material on top of a shallow, sandy, silty, gravel layer on top of a deep layer of soft organic silt and clay. Below the silt and clay layer was fine sandy material at the subgrade.

Jan 1, 2006

By Philip Dubbeling

Conventional dynamic sheetpiling techniques are ill-suited to urban development because of the emission of excessive noise and ground vibrations. Drilled shafts and slurry walls alleviate some of these environmental concerns but add additional problems due to large bulky machines, reliance on dusty concrete plants and urban trucking grief. To solve these problems, pre-fabricated sheetpiles are hydraulically jacked-in by reaction principle using a compact and lightweight press-in machine, a so called the "Silent Piler". Through scientific analysis, definition and systemization of press-in machines and methods, new construction concepts such as the one-step approach, implant structures, functional design and life cycle design have been developed to comply with new basic construction principles.

Jan 1, 2006

By Kazimierz Gwizdala

In recent years, in Poland the ATLAS piles have been successfully applied for some constructions near Gdansk. The piles have been used as foundations for housing and another areas of civil engineering, in delta Vistula geotechnical region, characterized by weak, highly compressible soils represented by mud and peat, lying in sub-surface layers, several meters thick. Usually below are dense sandy soils or gravel. In all cases, the base of ATLAS piles rested on sandy soils. The analysis of pile bearing capacity has been discussed and verified by static pile load tests (SPLT). The load-settlements characteristics obtained were satisfactory. In the paper, the results of geotechnical investigations as well as calculations and load tests are shown. The ecological aspects of ATLAS piles application within highly urban areas of the cities and complex geotechnical conditions are emphasized.

Jan 1, 2006

Jan 1, 1987

By James W. Weaver

The 2,120-foot long cable stayed Penobscot Narrows Bridge that carries US Route 1 over the Penobscot River between Verona Island and Prospect, Maine is supported on four foundation units, one below each pylon and one at each abutment. Due to varying subsurface conditions along the bridge alignment, the structure was designed to be supported on foundations consisting of high-capacity steel H-section piles (Verona Pylon), a mat bearing on a prepared bedrock surface (Prospect Pylon) and spread footings bearing on compacted rockfill (abutments). The 70-foot by 80-foot (plan area) Verona Pylon foundation was designed to be supported by 288, 430-kip design capacity steel H-section piles (HP14x117, 50 ksi steel) driven through up to 100 feet of dense glacial till deposits containing cobbles and boulders up to 3 feet in diameter. The piles were installed using a single-acting diesel hammer (Delmag D62-22) with a maximum rated energy of 165 kip-ft. Thirteen representative piles were selected for dynamic testing (ASTM D-4945) to verify pile capacity, hammer efficiency and pile stresses. Dynamic testing determined that four different pile driving criteria were needed across the site due to variation in the bedrock and soil resistance below the footing plan area. Approximately 4 percent of the production piles were damaged/rejected due to misalignment and/or damage as a result of encountering the cobbles and boulders embedded in the glacial till. The rejected piles were located randomly throughout the plan limits of the foundation mat. Subsequent structural analyses indicated that the foundation was capable of safely supporting the design loads without the need for installing replacement piles. Evaluation of dynamic testing results with signal matching and pile driving records provided valuable information on pile side and tip resistance. Evaluations were made regarding predicted versus actual pile lengths, pile bearing material, distribution of skin friction and end bearing capacities.

Jan 1, 2011

By Rick Deschamps, Brian Barkauskas, Aled Hughes, Abigail Stein

In central Washington, six miles south of the small town of Vantage, the flow of the Columbia River is harnessed by the Wanapum Dam which is part of the Priest Rapids Hydroelectric Project owned and operated by Grant County Public Utility District (GCPUD). Extending more than 8,300-feet from bank to bank, the dam includes left and right earth embankments, left and right concrete gravity sections and a 10-unit powerhouse. Adjacent to the right embankment is a concrete gravity spillway featuring radial gates measuring 50-feet-wide and nearly 70-feet-high. In the early 1960’s when Wanapum Dam was built, these seven-story spillway gates were the highest in the world. In late February 2014, 50-years into its service life, during a routine maintenance inspection, observant workers noticed a slight misalignment in the roadway deck curbs and handrails located on top of the spillway. Further survey and inspection efforts uncovered a 65-foot-long by two- inch-wide crack that spanned the full length of Monolith 4. On discovering the extent of the damage, GCPUD initiated immediate drawdown of the reservoir to relieve pressure on the spillway monoliths. Wanapum Reservoir and the areas directly downstream of the dam were immediately closed, boat ramps and inlets were left completely dry, campsites were closed and boating activity was banned on the lake until further investigations and remedial procedures were in place and completed. An extensive root cause analysis ultimately led to the conclusion that errors in the initial design calculations and late changes to the final spillway design led to a condition that generated tensile stresses in the concrete at the upstream face, which over a period of 50-years resulted in the formation of a crack along a horizontal lift joint located about 85-feet below normal pool elevation. Further analysis showed that, although visible distress was found at Monolith 4, there was nothing preventing this issue from happening at other locations along the dam spillway. Although no visible cracking was found in the other monoliths, repair procedures for Monolith 4 would have to be replicated at the remaining monoliths.

Jan 1, 2018

By Alan J. Lutenegger

Some years ago, a method was developed to incorporate a grout column around square-shaft helical screw-piles and anchors to increase shaft buckling resistance under compression loading. An additional benefit of this grouted shaft is to increase the load capacity in both compression and tension, depending on the geometry of the lead helical section and the soil conditions. Because of the unique construction procedure, the contribution of the shaft to the total capacity has largely been unknown. The behavior of grouted shaft helical anchors in clay was investigated by performing full-scale axial uplift (tension) load tests on a series of anchors installed at the University of Massachusetts Geotechnical Test Site. In order to isolate the contribution of the grouted shaft to the total load capacity, anchors were installed with a wooden dowel connection between the lead helical section and extension sections on three of the four anchors so that only the shaft resistance would be measured during the load tests. The grouted shafts ranged in length from 10 to 30 ft (3 to 9 m). Initial tests were performed approximately 5½ months after installation. Nearly four years after the initial tests were performed, the tests were repeated to evaluate any significant change in capacity with time and/or repeat testing (preshearing). The soil conditions at the site are presented along with the load-displacement curves for both the initial and repeat teats and a discussion of the analysis of the results. Repeat load tests showed an increase in capacity from the initial testing, however the percent increase was not the same for all depths. The results demonstrate that considerable shaft resistance can be developed in clays from the grouted shafts as might be expected. Depending on the L/D ratio of the shaft and the contribution of the lead helical section, at working loads the shaft capacity can dominate the behavior.

Jan 1, 2011

By J. Moskowitz

Construction of the new JFK International Airport Light Rail System (LRS) began in 1998 with a pre-construction load test program. This $1.2 billion design-build project consists of approximately 13 kilometers of elevated twin rail. The elevated rail system is supported on nearly 500 piers requiring deep foundations. The presence of underlying compressible and liquefiable soils as well as space constraints precluded the use of large spread footings. In the 1980's the Port Authority undertook extensive testing to evaluate various piles and drilled shafts types. The LRS piling sub-contractor and the Geotechnical Engineer conducted additional tests for this project to identify the most cost effective deep foundation type. Candidate piles types included: Monotube®, Tapertube®, and closed ended pipe piles. The tapered pile types were found to be the most cost effective and the project utilized both the Monotube® and Tapertube® piles. This paper presents the results of the load test program and the issues related to pile driving induced vibrations and ground movement.

Jan 1, 2000

By Tsunenobu Nozaki

"AbstractThe PRESS-IN METHOD is widely recognised as “an environmentally friendly piling method”. However, this characteristic is only one of the fundamental advantages of the method and this paper presents the most up-to-date capabilities of the method. Due to the evolution in recent years, the Press-in Method is now applicable to 2.5m thick retaining walls, over 50m deep foundations, overcoming rock conditions and confined construction conditions.The Press-in PrinciplesThe basis of the Press-in Method is simple. The Silent Piler presses a pre-formed displacement pile into the ground by static jacking force. The reaction for the Press-in Force is generated by gripping previously installed piles. As a pile is pressed into the ground, “A Pressure Bulb” is formed around the pile toe. Accordingly, higher bearing capacity can be generated compared to driven piles without disturbing the ground and producing any vibration. (A comparison of jacked, driven and bored piles in sand (2005), Deeks et al.)Applicable Pile ProfileThe Press-in Method is applicable to most of the steel piles available on global market i.e. U sheet pile in single form and pair, Z sheet pile, also in single and pair and Tubular Pile as described in Figure 2. Wall thickness of those piles can be 0.3m to 2.5m and moment of inertia of the wall ranges up to about nine million biquadratic cm per meter, which can deliver similar elastic modulus EI (kNm2/m) to 2.0m thick diaphragm walls and can be utilised for extremely deep excavations required in today’s construction industry"

Jan 1, 2014

By B. H. Moore

The opportunity to evaluate the pile design procedures used on a major project is an infrequent occurrence. It is even more infrequent that the project involves piles with significant tension and horizontal capacities. This report synopsizes over twenty years of design and construction experience on just such a major pile founded structure. The philosophy governing foundation design procedures is described and discussed. The order and extent of full scale pile testing are evaluated. Principal points in the specifications are established and their effect on construction progress and claims are noted. The report concludes with recommendations for future projects.

Jan 1, 2010

Precast prestressed concrete piles designed to be end-bearing in a sand stratum at Drax Power Station met with extremely variable resistance during driving. Some piles came to virtual refusal almost immediately on entering the sand whereas others were driven to considerable penetration with very low resistance. Redriving and load tests on piles experiencing low resistance on initial drive showed that take up in strength occurred over a relatively short period of time. Investigations involving the use of pneumatic piezometers revealed the development of significant excess pore pressures during driving. Samples from boreholes showed that piles met the least resistance when the sand had a high silt content. Comparison with the original site investigation data demonstrated the difficulties in predicting detailed pile behaviour. The varied behaviour could not be related to the original borehole logs or to SPT or static cone penetrometer results. The factors controlling pile driving behaviour were essentially geological and could only be explained with reference to local soil grading.

Jan 1, 1989

By Aly M. Mohammad

The 12th and 14th Street Viaducts, which carry Route 139, are located west of the Holland Tunnel in Jersey City, New Jersey. The two viaducts, provide access to and from the Holland Tunnel (which connects New York City and New Jersey) and carry upwards of 50,0000 vehicles per day from Jersey City and New York City to points west. The New Jersey Department of Transportation (NJDOT) selected AECOM to perform design services including rehabilitation and seismic retrofit for the 12th Street and 14th Street Viaducts while maintaining traffic at all times. Building a new parallel bridge just north of the 14th Street Viaduct was essential in avoiding extremely costly traffic delays. Installation of the new foundation, in close proximity to the existing viaduct, required drilling through some of the existing timber piles supporting the bridge. As a result, the existing bridge was required to be reanalyzed for this new foundation configuration. This proposed structure consisted of 8 piers each supported on a single six (6) foot diameter drilled shaft. Currently this portion of the bridge structure has been constructed. The shafts were constructed with rock sockets that were five feet six inches (5?- 6??) in diameter and were extended 11.2 feet (3.4 meters) into rock. A 2300 ton Osterberg Load Test was performed on one production shaft to confirm the capacity of the shaft. The rock socket for the test shaft was in sandstone. This paper will present a description of the design methodology and construction methods adopted for the foundations. In addition, the paper will illustrate the Osterberg Load Test including: equipment used, number and locations of strain gages, and interpretation of results. Additionally, regarding the close proximity of the new foundation, the paper will present the type of equipment used to drill through the existing timber pile foundation while minimizing the impact on the integrity of the existing foundation. We will also present the method of analysis for analyzing the redistribution of load on the remaining piles. The results presented in this paper will assist the design engineer by providing a comparison between the geotechnical design assumptions and the actual measurements obtained by field measurements for this rock formation.

Jan 1, 2009

By Guan Jichang

An abandened breakwater, located at the rear of No. 2 berth in Dongdu Port area of Xiamen City, was not cleaned thoroughly when the backfilling of sand started. The uncleaned stone layer was about 2 to 3 meters deep, with the average piece of stone weighing about 1 to 3 kN. A large grain storing house, 220X 60m2 in area, was designed and built at the above mentioned complicated site. The foundation of the grain house are made up of the cast-in-situ piles. It is well known that it is difficult for the submarine engineering drill to go down through such large-sized stones. Having com-pared the various plans, a final decision has been made which involves explosions with small amounts of charge plus cone bit in the enlarging of the size of the pores. Such a method has successfully prevented the pores from slumping and made it possible to fulfill the project without any difficulties. This paper also introduces the ways in effectively dealing with each individual stone.

Jan 1, 1991