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By N. Charue

An international prediction event was carried out within the framework of a 30-pile testing program organized in a sandy soil in Belgium (Limelette). That program called upon sev­eral testing methods: static load tests, Statnamic testing, and dynamic testing. This paper provides a summary of received predictions and results obtained from the static pile load tests, which were carried up to failure of the instrumented piles. The comparison between predictions is made using load-settlement curves with reference to the results of the static load tests. The predictions are based on a geotechnical approach using an extensive soil investigation program and a dynamic approach using the dynamic load test data.

Jan 1, 2002

By Alan B. Wagner

The River Tower is a proposed 27-story condominium building in the heart of downtown Milwaukee, Wisconsin (USA). The tower will be over 100 m tall, and will have a ground area measuring 15 m by 40 m. The structure will be constructed of cast-in-place reinforced concrete. Certain transfer girders and stabilizing diagonals will be constructed of post-tensioned concrete. Vertical loads will be transmitted through an arrangement of columns, bearing walls, and elevator and stair cores. A mat foundation will be used to connect and integrate these load-carrying elements. The site's geologic profile includes 8.4 m of compressible estuarine (organic) deposits. To control settlement, the mat will be pile-supported. These deposits are underlain by moderate-strength inorganic deposits that extend to bedrock at 32 m.

Jan 1, 2002

By S. H. Miller

Biodegradable hydraulic fluids can save tens or hundreds of thousands of dollars in fines and clean up costs in the event of a hydraulic fluid leak or spill. When properly selected, applied, maintained and monitored, a biodegradable fluid will have a long useful life and will protect equipment as well as or better than conventional petroleum based hydraulic fluids.

Jan 1, 2000

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 Matthew Janes

Quality control procedures are increasingly important with today's higher capacity foundations and complex loading conditions. The need for a mobile, repeatable, nondestructive and economical load test method led to the development of an entirely new approach. The system described involves using solid propellant fuels to accelerate a reaction mass off the test pile. The force required to accelerate the reaction mass upward acts equally downward on the pile. Very high forces may be applied to the pile in a controlled, linearly increasing manner. The duration of the applied load is approximately 100 milliseconds. This rate of loading is slow enough to allow the pile and soil to react together as a composite rigid body. Pile/soil accelerations and velocities are low, typically 1 g and 1 m/s respectively. The effects combine to produce pile and soil response no longer dominated by the transfer of force via stress pulse (as with impact). Instead the pile force increases throughout the length of the pile, with pile top and toe stresses building in unison with time. This emulates the stress condition during static pile loading. Finally, state of the art instrumentation systems are used to obtain test data. Displacement is monitored directly using a laser datum and integrated receiver located at the centre axis of the pile. Force is also monitored directly using a calibrated load cell. Data is acquired and digitized using a 386 PC with user friendly software capable of producing load deflection curves and time histories in the field seconds after testing.

Jan 1, 1990

By Reda M. Bakeer

"Measurements obtained during load testing of two steel H-piles driven at a site in Northeastern Mississippi are discussed. The general site conditions, equipment used, testing procedures and results of the pile load tests are presented. Both piles were tested in compression and one of the piles was subsequently tested in tension. The piles were instrumented with strain gauges and extensometers to measure the mobilized soil resistance and pile movement. Three different “zero strain” conditions were used to determine the mobilized soil resistance and residual loads due to driving or a load cycle. It was concluded that the effect of residual loads on driven piles could be significant. Driving residual loads influenced the magnitude and distribution of the load transfer curves more than those due to a load cycle. Results of the tension test were impacted by the residual loads from the previous compression test performed on the same pile.INTRODUCTIONSeveral factors affect the performance of a deep foundation system including the subsoil conditions, loading settings, pile type and installation method. Residual stresses develop in piles particularly due to pile driving, but they are typically not accounted for in the analysis (Fellenius 2002). Siegel and McGillivray (2009) presented an assessment of residual loads measured during load testing of instrumented auger-cast-in-place (ACIP) piles. The magnitude and distribution of residual stresses along the pile shaft and toe depend on the pile installation method, previous load cycles and time effects. Poulos (1987) reported that residual load due to driving at the pile toe is independent of pile driving equipment and may significantly affect the results of a pile load test. Hunter and Davisson (1969) reported results of pile load tests performed in compression on fully instrumented piles driven in cohesionless soils along with a discussion of the effects of residual loads. Tension loads of about 445 kN (100 kips) were measured at the pile toe after driving. Unloading residual compression load at the toe was detected as “apparent” tension since the instrumentation was zeroed prior to the test. The researchers suggested a graphical approach to obtain the “corrected” load distribution curves considering that residual load will dissipate following the tension test. Holloway et al. (1975) conducted a study on the effect of residual stresses due to pile driving and developed a computer software that accounts for residual loads. Briaud and Tucker (1984) suggested a method to account for residual loads based on the results of 33 pile load tests performed in mostly cohesionless soils."

Jan 1, 2017

Jan 1, 2000

By Garland E. Likins

High-strain dynamic testing of drilled shafts and cast-in-place piles has become routine procedure in many parts of the world today. Field testing is performed by measuring strain and acceleration records under impact of a falling mass. Wave equation analysis is utilized to design the weight, drop height and cushion of the hammer apparatus to assure a successful test. The Pile Driving Analyzer* (PDA) and CAPWAP* methods are used for data acquisition and analysis. Testing results yield information regarding pile static bearing capacity, structural integrity, and pile-soil load transfer and pile load-movement relationships. This paper discusses application of high-strain dynamic testing to cast-in-place shafts with emphasis on aspects unique to this type of pile. Suggestions regarding minimum requirements for good quality tests are offered. Five case histories reported in the literature are summarized and a sample specification is also included.

Jan 1, 1995

By Sikko Doornbos

For the extension of the Paper Mill of Parenco in Renkum, the Netherlands, the application of a pile foundation was required. The demands for this pile foundation were very explicit a vibration free and soil displacing pile systems with low allowable settlement. Another important aspect was the total amount of piles (originally over 1600 auger piles) which had to be executed within 3 months, in very difficult and unhomogeneous soil. Based upon these conditions the Tubex Grout Injection Pile was chosen to be used for this project. This system involves the drilling of a steel tube with a conical pile shoe while grout is injected at the point simultaneously, creating a mixed-in-place layer around the tube. INTRODUCTION After extensive marketing, the board of directors of Parenco, decided to a large extension of the production capacity of its paper mill by building a new production building called Paper Mill 1 or PM-1. The new PM-1 extension had to be constructed beside the existing PM-2 because of limited terrain. The site is located right between the Rhine river and Renkum, approximately 15 kilometers (10 miles) west from Arnhem (see figure 1). The construction involved the building of the PM-1 extension of approximately 250 meters (820 ft.) long by 40-60 metres wide (130-200 ft.). The main structure was to be constructed of precast concrete beams and columns.

Jan 1, 1987

By Liqun Liang

Various nondestructive testing (NDT) inspection methods are available to evaluate the structural integrity of cast-in-place shafts. The widely used methods include Cross Hole Sonic Logging Testing and Low Strain Testing. Due to its advantages such as low cost, easy operation, quickness and flexibility (no need to plan ahead and prepare inspection tubes or other devices), Low Strain Test is frequently specified in quality assurance programs of many countries or when doubts arise as to the integrity of the finished shafts/piles. The method is well suited for small to middle sized shafts. However it is an indirect NDT testing method and has certain limitations. Data interpretation requires proper training, experience and judgment and, therefore, inconsistent conclusions and reporting may be provided by different testers. To avoid or reduce such inconsistencies, it is best to follow a standardized data interpretation and record classification system. In this paper, a new classification method is presented with examples. A step-by-step data evaluation and interpretation procedure is proposed with examples of real cases to help understand the LST data. The paper also makes recommendations for measures to be taken when anomalies are detected in tested production piles.

Jan 1, 2011

By the courtesy of Metropolitana Milanese (Milan Underground), roost of the delegates visited on April 12, 1991 the tunnel of "PORTA VENEZIA" STATION of MILANO RAILWAY LINK. The "PORTA VENEZIA" STATION will be the most important in the link and it will he also the largest underground project of the whole railway transport network in Lomhardy. The particular conditions of the soil and the collocation of site in the center of Milano have required new technologies and the technical solution applied to this job is called "Cellular Arch Method" by its designer Prof. P. Lunardi. Our sincere thanks go to Prof. P. Lunardi and Eng. E.M. Pizzarotti of Rocksoil, Milano who have kindly furnished us a technical description of this method. Eng. Pizzarotti was the guide during the visit and gave all the technical explanations to the delegates. THE "VENEZIA" STATION IN THE 2PB SECTION OF THE RAILWAY LINK The excavation of cavities in loose ground, exceeding a certain dimension and at shallow depth, is not feasible using traditional methods: in fact it is not possible to consolidate the ground around the cavity in such a way that homogeneity and resistance is sufficiently guaranteed.

Jan 1, 1994

By Kirk A. Mcintosh

Augered, cast-in-place (ACIP) piles have been utilized in the United States for a wide range of projects since the 1950's. Due to the cast-in-place nature of the installation method (and lack of a driving criteria); however, ACIP piles have not been readily accepted by some practicing geotechnical and structural engineers. Since ACIP piles were initially developed, the installation equipment and techniques have been improved and refined and the number of experienced contractors has significantly increased. Over the past 10 to 15 years, the pile type has experienced significant growth in the United States (particularly in Florida) because engineers have become more knowledgeable and comfortable with its use. The Miami area, in particular, has experienced considerable growth in the utilization of ACIP piles primarily due to their usage on the $1 billion Miami Metrorail System project in the early 1980s. The economic advantages over other deep foundation types, coupled with some unique installation advantages, have shown that ACIP piles can be a viable foundation alternative on many projects. Even though ACIP piles have gained respect in the private sector, the pile type has generally not been readily accepted by government transportation agencies. The reluctance to readily accept this foundation type stems primarily from the quality assurance aspect of cast-in-place pile construction. Additionally, there has not been much research activity on this foundation type, technical papers, formal associations (other than the DFI), or a concerted effort to standardize the industry. This paper serves to discuss the state of practice for ACIP pile installation in the state of Florida.

Jan 1, 1997

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 Fredrik Sarvell, Leo-Ville Miettinen, Veli-Matti Uotinen

"Abstract The continued concentration of building activities in cramped areas of city centres means more underground construction and facilities. Demand to minimize execution time and any kind of disturbance to business, general traffic, people and nearby technical structures is increasing. To answer these challenges foundation business has to develop schedule-wise and technically reliable deep excavation and foundation solutions in vulnerable surroundings and challenging soil conditions.Drilled pipe pile wall – RD-pile wall – is a combination of Ruukki drilled steel pipe piles and interlocking sections. Individual RD piles, typical diameters between 219 mm to 610 mm, are connected to each other with interlocks welded to the piles on the automated welding line at the workshop. The matching dimensions of the drilling system and interlocking sections allow the installation of RD piles through stones and boulders and even into the bedrock, if necessary, in a single operation. Installation is done by a down-the-hole hammer (DTH) using the centric drilling system and oversized ring bits or a drilling system consisting of a pilot bit and reamer wings.RD-pile walls have been used as permanent and temporary retaining walls for different kinds of demanding excavations and structures, such as bridge foundation, as quay wall and as sealing structure in rehabilitation of an existing dam. Rigidity and watertightness of the lower end of the RDpile wall is being researched as well as fire design issues examined. One of the most fascinating RDpile wall solution is to utilize the wall as a permanent underground basement wall. Reliable and rigid connection to bedrock decreases the bending moment and deflection of the wall and good fire resistance in addition to large variety of pile dimensions and steel grades gives possibilities to design and execute a cost-efficient basement wall and foundations without temporary retaining wall works. 1. IntroductionIn northern Scandinavian soil conditions, installation of sheet pile walls, or even secant pile walls, is often problematic due to the existence of hard and large boulders in the overburden, and especially when the retaining wall structure should penetrate to or into the hard bedrock. On the other hand, an efficient and reliable piling technique suitable for the demanding soil conditions described above, percussion drilling, has been developed since the 1960’s, and especially from the mid-1990’s, when the concentric drilling method with the ring bit and pilot was introduced. A new retaining wall application, the RD pile wall was developed by combining that drilling method with the widely used retaining wall solution based on steel pipe piles and welded interlocks (a pipe pile wall normally installed with vibratory or impact hammers)."

Jan 1, 2014

By A. L. Garassino

Dans cet article on parle sortout de l'approche de calcule pour les pieux charges horizontalement avec particuliere reference aux curbes p-y et è une solution semi-empirique qui prende en consideration les variations typiques du module du sol avec la deformation obtenue par les données expérimentales. 1. INTRODUCTION The analysis of the piles under lateral loads depends very strictly from the pile stiffness and geometry, from the soil type and from the strain field. Different approaches were adopted in solving the problem. Some Authors developed methods for estimating the ultimate lateral resistance of piles and pile groups by conventional static approaches, as the Brom's widely known (1964) or by the plane strain solution developed by Davis (1961) or by empirical engineering con­siderations l

Jan 1, 1994

By Gary L. Seider

Helical screw piles are used in various applications including the underpinning of distressed foundations and as deep foundations for new structures. At present, maximum design loads range between 12.5 and 50 tons. Helical piles installed with in-situ grouting of the central steel shaft are a relatively new type of deep foundation, which have extended the present maximum design loads to the 100-ton range. Vickars & Clemence discussed this new foundation system in a paper presented at GEO-Denver 2000 in Denver, CO. Over the past three years, grouted shaft helicals have been used successfully on remedial and new construction projects all across North America. The authors have studied several construction projects in a variety of soil conditions to compile a list of practical design guidelines. Those guidelines include installability of grouted shaft helicals based on soil type, equipment requirements, grout selection, and theoretical vs. actual load capacity. In a number of cases, full-scale, field load tests were conducted in both granular and cohesive soils and the results broken down between tip resistance on the helix bearing plates and friction resistance on the grouted shaft. Data is presented which will further efforts to develop a design model and method to accurately predict the axial and lateral capacity of grouted shaft helicals.

Jan 1, 2003

By Fawad S. Niazi

Ever since the use of the cone penetration test (CPT) in geotechnical practice, attempts have been made to correlate CPT parameters with pile capacity components of unit end bearing (qb) and unit shaft resistance (fp), thus deriving multiple CPT-based pile design methods. These methods focus on "capacity" only without consideration to complete axial pile load-displacement (Q-w) response. Estimated capacities from these methods also exhibit considerable scatter without any consensus on their consistency. In addition, load-displacement curves obtained from axial load tests on highly expensive and extensively instrumented piles can exhibit different shapes. Nevertheless, a single value from the curve so obtained dictates the design capacity. Currently, there are at least 42 different criteria defining capacity with considerable variation in the values obtained thereof. The Randolph elastic solution, which provides a framework for analytical evaluation of pile load-displacement response, requires the profiles of soil stiffness. The fundamental soil stiffness defined by the small-strain shear modulus (Gmax) can be obtained from shear wave velocity (Vs) readings via seismic piezocone tests (SCPTu). The secant stiffness (G), which softens from Gmax corresponding to operational load levels, can be obtained by generating stiffness reduction curves from back analysis of load tests. Then, using appropriate G values, the Q-w curve can be defined for conditions similar to the database from the pseudo strain (w/d). Thus, a complete framework for optimal integration of SCPTu data, Randolph elastic solution and back-analysis of field operational stiffness can be established for complete axial pile foundation analysis.

Jan 1, 2011

By William D. Spielvogel

The Massachusetts Highway Department awarded the Porter Street Outfall Project to the J.M. Cashman Company in November 1991. Timely completion of the Project in one and one half years is critical to the start of the subsequent Third Harbor Tunnel North Approach project. Existing subsurface conditions and the Project's location at Boston's Logan International Airport significantly increases the difficulty of construction. The major contractual work involves relocating a reinforced concrete double box culvert supported on a continuous wood pile foundation. This existing culvert crosses and interferes with the future Third Harbor Tunnel North Approach alignment. Two parallel culverts constructed approximately 20 feet from either side of the future Third Harbor Tunnel alignment replace the existing double box culvert structure. Under the original contract design, approximately 3,100 feet of 14 ft. by 15 ft. reinforced concrete culvert is cast in place adjacent to the west side of the Third Harbor Tunnel and is located in the center of the Airport's main service roadway, Harborside Drive. This culvert is the Porter Street Combined Sewer, PSCS, which handles a combined flow of sewerage from the East Boston community and storm water runoff from Logan Airport. In addition, approximately 2,230 feet of 17 ft. by 15 ft. reinforced concrete culvert is cast in place adjacent to the east side of the Third Harbor Tunnel and is within 20 feet of an active aircraft taxiway and heliport. This culvert is the Bird Island Flats Storm Drain, BIFSD, which handles storm water runoff from the Logan Airport airfield. The existing outfall, on the west side of the Third Harbor Tunnel alignment is to remain in service and is to be connected to the new PSCS and BIFSD culverts. Therefore, a portion of the BIFSD culvert is designed as a bridge to span 128 ft. across the Third Harbor Tunnel excavation during construction.

Jan 1, 1994

By Douglas Brittsan

This paper presents pile tension and compression load test results for the Southern Freeway Viaduct (North) pile load test site. The testing program represents a collaboration between California Department of Transportation (Caltrans), Federal Highways Administration (FHWA), and a group of pile manufacturers and construction firms. The participating manufacturers included Fundex, Halliburton, Monotube, and Nicholson, with each firm supplying proprietary pile systems. The field test program measured and will allow the direct comparison of the tensile and compressive capacity of nine common and proprietary pile systems installed in nearly identical soil conditions. Data reported here-in details pile compression and tensile load-deformation measured at the pile head. Cursory data regarding pile installation details are included to aid in data interpretation.

Jan 1, 1993

By Jesús E. Gómez

This work is a continuation of a paper presented in the 32nd DFI Annual Conference, Colorado 2007, titled ?Hollow Core Bar Micropiles - Design parameters interpreted from 260 load tests.? The first paper presented the results of the verification and proof tests performed for the retrofit of two bridges with hollow core bars that used 260 micropiles. It included an interpretation of the unit bond values in the different soils where micropiles were installed. Recently two additional bridges within the same geological environment were also retrofitted using 144 hollow core micropiles. This paper includes the interpretation of the additional data from the proof tests performed and refines recommended values for design of hollow core bar micropiles in soils similar to those encountered in these two projects. The authors believe that the data collected will significantly add to the relatively small existing database on micropile tests and may also be useful during implementation of the LRFD design methodology.

Jan 1, 2008