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By K. Rama Sarma

Piles are frequently subjected to lateral forces and moments in addition to vertical forces and hence the piles have to be designed for both lateral loads as well as vertical loads. In the design of such pile foundations, two criterias must be satisfied. First an adequate factor of safety against ultimate failure and second, as acceptable deflection at working loads. In this study the work has been carriedout to study the lateral deflection pattern of the pile. The solutions to the problem primarily depend on soil modulus. Equations for computing the values of slope, deflection and coefficients for many types of soil conditions have been developed for static loading for long piles. As analysis part is not available for the above methods for the values of depth coefficients in the tables. It is required to go for linear interpolation which is not valid and highly unreliable. In this present method, coefficients can be obtained for any value of depth coefficient (z) with simple calculation. The present method is very concise and allows one to ana­lyse any type of pile with varying depth coefficient (z) even without the availability of any practical data regarding applied lateral load (P1) and moment (M1).

Jan 1, 1996

By Satyajit Vaidya, Rudolph Frizzi, Sandy Larimer

"This paper presents a case history in design and construction of a deep foundation system that included high-capacity open-ended driven piles constructed to support a high-rise building in Manhattan, New York. The project site is bordered by existing buildings, active streets, and critical public transportation infrastructure, which were considered in the new building’s deep foundation and seismic design. This paper focuses on driven pile foundation design and installation through relatively loose soil deposits. Unique design aspects included seismic design considerations, and pile splice design for open-ended steel pipe piles subject to significant uplift and lateral loading. Unique construction aspects included quality assurance of open-ended steel pipe pile splices, and uplift and lateral load testing of driven piles installed in close proximity to other foundation elements installed for the project.SITE CONDITIONS AND SUBSURFACE CONDITIONSThe project site is located in Manhattan, New York, and is bordered by existing buildings, active streets, and critical public transportation infrastructure that is located about 60 feet from the site. The existing sidewalk grades around the site are between about el 4 and about el 13; elevations are referenced to the North American Vertical Datum 1988 (NAVD88).Subsurface conditions at the site generally consist of successive strata of historic fill, former river bottom deposits consisting of compressible clayey soils, and medium dense to dense sand, overlying mica schist bedrock. A generalized subsurface profile is shown in Fig. 1. The historic fill stratum is about 10 to 45 feet thick, and generally consists of loose to medium dense sandy soils with varying proportions of silt, gravel, and miscellaneous debris such as brick, concrete, and glass fragments. The underlying former river bottom deposit stratum is up to about 15 to 20 feet thick, and generally consists of very soft to very stiff clay and lenses of very loose to loose sand. Medium dense to dense sand was generally observed below the historic fill and former river bottom deposit strata and overlying bedrock. Top of bedrock was generally observed at about 80 to 105 feet (i.e. at about el -75 to el -100), except in the southeastern portion of the site where the top of rock was observed as deep as about 140 feet (i.e., at about el -135). Groundwater levels typically ranged between about el 1.5 and el -0.5."

Jan 1, 2016

By Abid O. Adekunte

The design, construction and monitoring of the deep excavation support for the basement of a large-scale commercial development in Cavan, Ireland is presented. Excavation area was adjacent to existing structures and retained height H varied between 4.0m ? 11.0m. In areas where excavation depth H < 5.0m, wall was designed as cantilevered section. However in sections where 5.0m = H = 11m, additional wall supports were required for serviceability reasons. Traditionally, designers often provide additional wall support through the use of tie-back ground anchors, raking props and braces. On the current project, the main contractor was not in support of the use of temporary props so as to maximise working space, while owners of adjacent properties disapproved the use of tie-backs. The limited set-back between the wall line and site boundary also contributed to the complexity of the project. A rare alternative solution has been adopted. This novel approach involved buttressing the wall with steeply raking bored tension piles at regular intervals along the wall. Comparison of the monitored deflections in the cantilevered sections with those recorded at sections where tension piles were used shows the novel solution to be safe and quite effective. This approach is also considered to be more economical when compared with ground anchorage and propping.

Jan 1, 2008

By H. S. Radhakrishna

Foundations supporting power transmission and communications towers are subjected to both compression and uplift loads, often of a cyclic nature. Some novel foundations, combining the beneficial features of grouted and helix anchors with that of compression piles and grillages, were developed by Ontario Hydro during the construction of high voltage transmission lines in Ontario, Canada. In addition to meeting the load requirements, the foundations permit easy installation in swampy areas and also minimize impact on environmentally sensitive terrain. This paper describes the features of these composite foundations and outlines the performance criteria used for their design and installation on the basis of load test results.

Jan 1, 2010

By Srijit Bandyopadhyay, Aniruddha Sengupta, G. R. Reddy, Raj Banerjee

The objective of the present endeavor is to compare the performance of a pile raft system in foundation sand subjected to lateral loads. To study the behavior of pile raft system in sand a laboratory test was conducted on small scale model foundation system. The raft and pile was modeled by square concrete foundation of 250 mm x 250 mm x 15 mm in length, breadth and thickness and 25mm diameter and 250mm long circular pile located at the center of the raft. The system was tested under static lateral loads of 6.25N, 12.5N, 18.75N and 25 N respectively resting on dry Kasai River sand. A vertical surcharge pressure of 1.5kPa (10 kg) was applied on top of the model raft for each case. The results of the model tests have been simulated by a general purpose 3-D finite element software and the model has been validated with experimental results. The moments of the pile obtained from the model tests and those predicted by the numerical analyses for all the lateral loads matches reasonably well. For matching the trend of bending moments obtained from experiments, validation with theoretical results have been done with the help of Matlock and Reese (1960) approach for a single value of lateral loading. Moreover, a parametric study has been conducted with 5mX5mX0.3m raft size with 0.5m diameter and 5 meter long pile with increasing number of piles namely 2, 5 and 9 respectively to study the response in terms of moment and lateral deformation under available earthquake loadings, like Loma Prieta (1989) and Darfield Christchurch (2010). Bending moments of piles and load deformation curves for lateral loading have been studied for each case in which it is observed that the bending moments of pile significantly reduces (around 4 times) as the number of pile is increased to two, but it decreases to a nearly constant value (it saturates) as the number of pile is increased to five and nine. Moreover, the lateral deformation of piled raft system drastically reduces (around 2.4 times) for two pile system, and it saturates to a constant value with five and nine pile system. All these results indicate the constancy of stiffness irrespective of the number of piles in the piled raft.

Jan 1, 2015

By Emad Farouz, Francis A. Abreu

"This paper presents a case history of a successful construction-phase pile load test program that optimized the pile design in challenging ground conditions at the Great Neck Wastewater Treatment Plant in the Town of North Hempstead in Nassau County, New York. The improvements and expansion of the wastewater treatment plant included the construction of several new structures to comply with new stringent nitrogen discharge requirements and new design flow. The challenging ground conditions included up to 20-ft thick organic deposits with weight of hammer blow counts and up to 14 percent organic content and tidal ground water that was near the ground surface. The foundation design evaluated various deep foundation alternatives and selected driven closed-ended pipe piles then filled with concrete as the most suitable foundation. The selection process included considerations of cost, risk, vibrations, noise, and schedule. The contract documents utilized an innovative approach of performing an optimization load test program that was implemented during construction to optimize pile lengths and reduce potential vibration and construction schedule.This paper discusses the details of the successful load test program including static testing, dynamic testing, and the innovative contracting approach utilized to implement the construction phase load test program. It also discusses the successful development and implementation of driving criteria for production piles and construction challenges. The successful load test program resulted in savings of several hundred thousand dollars, optimized schedule, and lower environmental impacts.SITE AND PROJECT DESCRIPTIONThe Great Neck Water Pollution Control District (GNWPCD), located in the Town of North Hempstead in Nassau, New York, owns and operates a municipal wastewater treatment plant (WWTP) that discharges treated effluent through an outfall to Manhasset Bay, which is a tributary of the Long Island Sound. The site is located west of Manhasset Bay and is surrounded on three sides by local roads, and commercial, industrial, and recreational properties. The site has a gentle slope ranging from elevation +20 to +7 from west to east, respectively, based on the Nassau County Datum.To comply with new nitrogen discharge requirements and new design flows, the GNWPCD contracted CH2M HILL, Inc. and William F. Cosulich Associates as a Joint- Venture (JV) to design and provide services during construction of eight new advanced nitrogen removal facilities."

Jan 1, 2017

By James S. Graham

Marine design and construction methods are presented on the caisson foundations for the tower piers at the Brooklyn, Ben Franklin, Delaware Memorial 1st, Tappan Zee, Walt Whitman, Throgs Neck, Verrazano Narrows, Delaware Memorial 2nd, and Newport Bridges. All of the bridges are founded on caissons, bearing on bedrock, soil, or piling. Caissons at the Tappan Zee Bridge are partially supported by piling and partially by buoyant forces. General subsurface conditions for each are provided. The purpose of this paper is inform engineers how bridge foundations using caissons were built over major waterways in the Northeastern USA in the past, anticipating a surge of new bridge construction in the near future.

Jan 1, 2013

By Emad Farouz

This paper presents a case history of a successful construction-phase pile load test program that optimized the pile design in challenging ground conditions at the Great Neck Wastewater Treatment Plant in the Town of North Hempstead in Nassau County, New York. The improvements and expansion of the wastewater treatment plant included the construction of several new structures to comply with new stringent nitrogen discharge requirements and new design flow. The challenging ground conditions included up to 20-ft thick organic deposits with weight of hammer blow counts and up to 14 percent organic content and tidal ground water that was near the ground surface. The foundation design evaluated various deep foundation alternatives and selected driven closed-ended pipe piles then filled with concrete as the most suitable foundation. The selection process included considerations of cost, risk, vibrations, noise, and schedule. The contract documents utilized an innovative approach of performing an optimization load test program that was implemented during construction to optimize pile lengths and reduce potential vibration and construction schedule. This paper discusses the details of the successful load test program including static testing, dynamic testing, and the innovative contracting approach utilized to implement the construction phase load test program. It also discusses the successful development and implementation of driving criteria for production piles and construction challenges. The successful load test program resulted in savings of several hundred thousand dollars, optimized schedule, and lower environmental impacts.

By F. Keith Jacobson

To be involved in the construction of a deep dredged caisson for a major bridge pier is one of the most rewarding and professionally challenging experiences one can have in the bridge construction business. That experience was doubled in the construction of the two deep dredged caissons for the Highway 82 Bridge over the Mississippi River near Greenville, Mississippi. The challenges and the construction risks associated with constructing these two dredged caisson pier foundations highlight the construction engineering innovation associated with major bridge pier construction. The 1,378-foot Main Span of the Highway 82 Bridge makes it the longest cable stayed bridge span over the inland rivers of the United States. The main piers for this bridge are supported on two dredged caissons measuring 80-feet by 122-feet in plan, founding 200-feet and 170-feet below the river surface. The challenges of constructing these caisson structures, sinking them through 70-feet of water to the river bottom and then excavating and further sinking them to the founding grade without exceeding the design tolerances, were enormous. The construction engineering opportunities for innovation included major breakwater structures to create a friendly environment in 11 ft/sec currents, the first time use of Articulated Concrete Mattresses for river bottom scour control, unique air dome design to maximize the buoyancy of the caisson structure while floating, a caisson guide system to assure positive control and positioning of the caisson during the initial sinking phases, and a comprehensive sinking plan to assure maximum control and minimum risk. Many of the innovative solutions to the construction challenges on this bridge will be incorporated into future caisson construction projects on the lower Mississippi River.

Jan 1, 2013

By Kashyap Chaturvedula, Emad Farouz

The paper presents a discussion on the axial capacity of deep foundation elements bearing in the Yorktown formation in the southeastern region of Virginia. The fossiliferous marine soils of Tertiary age Yorktown formation typically consist of silty/clayey Sand or sandy Silt/Clay with varying amounts of shell fragments. The Yorktown formation is generally divided into Upper and Lower Yorktown layers depending on the shell content and the percent fines. Results of multiple load tests performed by Jacobs Engineering on auger cast piles as part of water and wastewater treatment plant expansion projects in southeastern region of Virginia are presented in this paper. The paper describes the subsurface investigation methods used to study the existing subsurface conditions and the design methodologies followed to estimate the axial capacity of the auger cast piles. The paper provides details regarding installation of test piles, instrumentation, load testing procedure, and interpretation of test results. The paper presents a comparison between the various methods of estimating axial capacity of auger cast piles based on the SPT-N values, the empirical methods for the Yorktown formation and the load test information. The paper distinguishes the side resistance values obtained within the upper and lower Yorktown formations. The paper compares the various design methods to the multiple load test results and recommends a design modification that is closer to the load test results.

By Karen C. Armfield, Gisele R. Passalacqua, Joanna Smith

New York City is an urban environment with a history spanning over 200 years. The coastline of New York has changed over the years. In the East River, old bulkhead and remnant of relieving platforms together with variable bedrock elevations pose challenges in the design and construction of deep foundations. This paper presents a Case History of high capacity deep foundations along the Franklin D. Roosevelt (FDR) Drive on the Upper East Side in New York City. The project consists of a ramp that overpasses the FDR Drive allowing heavy trucks to access the Marine Transfer Station (MTS) facility built over the East River. Large diameter drilled shafts and mini-piles socketed to bedrock were designed and constructed. Remnant of old bulkhead was encountered at the site and a Ground Penetrating Radar (GPR) investigation was completed during the subsurface investigation phase of the design. This paper discusses details of the subsurface investigation program and design methodology of the high capacity drilled shafts and mini-piles. It also describes construction methods and results of Osterberg Load tests documenting the field values of skin friction through the rock socket. Other construction challenges include construction and drilling rock sockets for drilled shafts over sloping bedrock. 1. INTRODUCTION New York City is a renowned urban city that always calls for the most delicate, yet complex, and robust superstructures and most importantly substructure designs. The historic preservation of this large 200 years old city of 319 square miles is ever changing. Shorelines are often extended to accommodate new infrastructure and very often many miscellaneous structures are discovered below the ground surface. The East 91st Street Ramp was constructed to provide access to the East 91st Street Marine Transfer Station over FDR Drive and York Avenue. Another alternative ramp will be relocated to the South Bound (SD) of the FDR Drive at 92nd Street. A subsurface exploration program was completed in accordance with the New York City Department of Design and Construction (NYCDDC) general requirements, Section 4.5, to perform subsurface investigation along the FDR Drive in Manhattan, New York.

Jan 1, 2019

By Martin Walker, Joseph Ang, Jongwon Lee, Alvin Bayudanto, Lilian Lorincz, Morteza Khorshidi, Wenyong Rong

This paper presents a case history of liquefaction susceptibility evaluation study for a major infrastructure project in the San José area. The subsurface material of the study area consists of Holocene alluvial deposits composed of interbedded and crosscut clays and silts, sands and gravels. The simplified approach for liquefaction triggering evaluation was carried out using both CPT data and SPT data representing site’s seismic capacity and the peak ground acceleration associated with a return period of 975 years at ground surface representing seismic demands. Site-specific cyclic stress ratio (CSR) profiles as seismic demand are also estimated from one-dimensional site response analysis. The simplified approach uses empirical depth stress reduction factors (rd) based on generic shear wave velocity profiles to account for the non-rigid response of the soil profile in estimating CSR. The CSR profiles of the simplified procedure were examined by completing site response analyses using site-specific soil profiles to represent site-specific seismic demands in the liquefaction triggering evaluation. The paper concludes with a comparison and discussion of the liquefaction evaluation examining results from CPT versus SPT data, and the comparison of CSR profiles from the simplified procedure versus site-specific response analysis.

Sep 8, 2021

By Danny Winters, Wesley Schmutzler, Christopher Lewis, Matteo Bertoni

"SR 83/US 331 is a primary North/South roadway in Walton County that is a crucial link for tourism and commerce between the Walton County beaches and the heavily traveled I-10 corridor in the panhandle of Florida. The facility also serves as the primary hurricane evacuation route from southern Walton County. This 3.4 mile project involves expanding the current two-lane crossing of Choctawhatchee Bay to a fourlane facility to increase capacity and dramatically improve mobility within the corridor. One of the major goals of the project is to perform ground stabilization using Deep and Shallow Soil Mixing (DMM & SMM) along existing causeways. Ground stabilization is required due to the existence of moderately deep very loose soils that have settled considerably over the years. As a result, the Florida Department of Transportation (FDOT) incurred significant maintenance expenses and was unable to maintain an acceptable ride quality. FDOT considered soil mixing as one option to control this settlement. Quality Control for soil mixing relies heavily on the monitoring system used to control mixing parameters. This paper will examine in detail, the reporting of the Drilling Mate System (DMS) used to ensure the quality of each soil mixed element.INTRODUCTIONThe Florida Department of Transportation (FDOT) issued a Design-Build Maximum Price Request for Proposal (RFP) for the Choctawhatchee Bay Bridge expansion. The design-build (D/B) team of Skanska/Parsons Brinckerhoff was awarded the contract. The D/B team, in order to meet the unique deep ground improvement challenges of the Choctawhatchee Bay Bridge Project, selected Foundation & Geotechnical Engineering (FGE) as the engineer to design the ground improvement and TREVIICOS South (TIS) to execute the works.The FDOT in their RFP states that “either bridge or utilize a deep ground improvement method to stabilize the three segments of the existing earthen causeway” and “one possible method of deep ground improvement which is considered viable is deep soil mixing”. FGE developed a proposal to provide a unique rigid transfer platform to effectively stabilize the existing causeways. This platform (Fig. 1) consists of an upper 10 ft thick stabilized soil layer which transfers axial load to a series of deep columns. This robust system guarantees superior durability, ride quality and pavement condition and will exceed all required design and performance criteria including, “Less than 2 inches of settlement within a 1,000-foot section”."

Jan 1, 2017

By Konstantin G. Ashkinadze

The paper considers performance of piles supporting transient pipe anchors in heavy industrial pipelines. Events such as pump trips or opening and closing of large valves produce short-term dynamic pulses in the pipeline with variable spectral characteristics. Their magnitude is large enough to cause major damage to the pipeline and its anchors, which face horizontal impact loads amounting to hundreds of kN. Design of pile foundations supporting these anchors is often governed by limitation of deflection of the support to prevent overstressing pipeline connections and equipment nozzles. The maximum deflection does not always correspond to the largest load because the stiffness of the soil surrounding the piles heavily depends on the rate of loading. Faster actions encounter stiffer soil response while loads of smaller magnitude applied slowly may be more critical for the deflection time history of the anchor. A typical transient action has both high- and low-frequency harmonics, which makes the response complex. Using load rate-dependent p-y curves published in literature, the paper develops methods of analysis of pile foundations for transient anchors. Pile displacement amplitude – input frequency – natural frequency correlations and time histories of pile response are constructed for typical profiles of transient actions, considering nonlinear soil response to large horizontal loads.

Jan 1, 2016

By Takeshi Maki, Kh. Adeel Tariq

"The lateral resistance of the structure plays an important role during seismic event and it can be increased by using ground improvement. In this study an attempt has been made to investigate the effect of cement-treated sand on the lateral capacity of the pile. The behavior of piles surrounded by sand only and cement-treated sand confined in a steel box (30 x 30 x 50 cm) which is subjected to lateral cyclic load has been investigated. Piles having a diameter of 2.5 cm and embedded to a depth of 45 cm were used. Steel and aluminum piles were used to investigate the effect of flexural stiffness on the lateral capacity of the pile. Bottom supports of piles were also changed from pinned to fix. Well graded sand compacted to 70% of relative density (RD) was used. Cement-treated sand having a compressive strength of 3.7 MPa was used. Displacement controled lateral load tests were performed and cyclic loads were applied until pile displacement was 4%, 10%, 20%, 35%, 50%, 75% and 100% of pile diameter. Results evaluated are compared with common method of analysis like Brinch hansen (1961), Brom (1964), Poluos (1980) etc. Results have indicated that the stiffness of a pile affects its lateral capacity. The introduction of central cement-treated sand part increased 5 times the lateral capacity of piles as compared with a sand only condition.IntroductionPiles are used extensively around the world to support loads of structures. Piles are commonly used to carry axial load, but in some structures, the lateral capacity of the pile is more important than the axial capacity: for example piles supporting earth retaining structures, electric tower foundation, etc. Structures can be subjected to both axial and lateral forces, like structures constructed at harbor that are subjected to lateral force due to waves action; and structures built in earthquake prone areas like Japan."

Jan 1, 2017

By Kyle Murphy, John S. McCartney

This paper focuses on the seasonal thermo-mechanical response of two energy foundations installed at the new Denver Housing Authority Senior Living Facility in Denver, Colorado. The two drilled shaft foundations, which have diameters of 36 inches and depths of 45 ft and are end bearing in the Denver shale formation, include a closedloop series of polyethylene tubes through which fluid is circulated to exchange heat with the surrounding ground. The tubes within the foundations are coupled together with the conventional ground source heat pump system for the building and were installed to evaluate the heat exchange response of the foundations as well as any thermomechanical soil-structure interaction effects. A series of vibrating wire strain gages and thermistors were installed at different depths in the foundation to record the thermomechanical strain and temperature at different depths. Also, pipe-plug thermocouples are used to measure the inlet and outlet temperature of the heat exchanger fluid entering each of the foundations, which is necessary to evaluate the total heat exchange for the foundations and the efficiency of the heat pump. This paper will describe the energy foundation construction processes, the strain distribution and ambient temperature profiles during building construction and the seasonal strain and temperature distributions during heating and cooling of the building. The data indicates that typical heat exchange associated with heating and cooling operations leads to strains which are within acceptable limits, and that the foundations can provide a clear option for absorbing the base heating and cooling load for the building.

Jan 1, 2017

By Carl Ealy

Static and STATNAMIC (STN) rapid load test (RLT) was performed on 3-drilled shafts. The purpose of the RLT part of the study was to obtain data in support of FHWA research on innovative load testing methods. The research site is located at the National Experimentation Research Site (NGES) in Amherst Massachusetts and is underlain by Connecticut valley varved clay. Two of the tested shafts were constructed without planned defects and the third with manufactured defects to evaluate current non-destructive integrity testing (NDE) methods. Quick Load Test (QLT) and Constant Rate of Penetration (CRP) static axial load tests were performed on two shafts to plunging failure. Good agreement between static and RLT derived static failure loads was attained for a 5% failure criterion (load at a movement equal to 5% of shaft diameter).

Jan 1, 2002

By Peter J. Jancich

This paper describes the installation of high capacity Augered Pressure Grouted piles which support structural loading from a four level parking garage in west-central DuPage County, Illinois. The subject site is characterized by a variable glacial geology which presented, to the designer, a number of problems with respect to analysis and prediction of pile capacities, and, to the contractor, the very real difficulties associated with estimating the costs of, and installing foundation units in highly variable subsurface conditions. 2. General Site and Subsurface Conditions 2.1 Site Conditions - The subject site is part of an overall 300 acre property. Topographically, the overall site is saddle shaped with higher elevations along north and south boundaries and a subdued, east-west trending swale centrally located. Elevation relief is on the order of 25-30 feet (7.6-9.2m).

Jan 1, 1991

By Takefumi Takuma, Masashi Nagano, Koji Kajino

As part of the construction of a multi-span pre-stressed concrete girder bridge for Japan’s new high speed rail line, landslide preventive piles were installed on the flank of a steep slope. The rotary pressin piling method was selected to install three parallel rows of long (up to 36m, i.e., 118ft) and large diameter (1,200mm, i.e., 47.2in) pipe piles safely into the slope as a deterrent measure. They were spaced at 2.5 Dia (3.0m, i.e., 9.8ft) on center and were staggered to allow the groundwater to migrate between the piles. Each pile had a sacrificial cutting shoe welded at its toe for speedy installation and was rotated and simultaneously pressed into soil on the slope through the stable bedrock thereunder to achieve a robust landslide prevention in a relatively short period of time.

By T. Wulleman, M. Ansriou

Integrity testing is a primary quality control check on a product that is for the most part not accessible to visual examination. Their cost can be expensive when using direct methods of inspection (like coring a pile) or more economical when using indirect methods (e.g. acoustic testing). All indirect methods operate by “inference” which means that they do not directly measure the defect of integrity. Indirect methods measure the variation of physical values (temperature, impedance, speed, ect.) correlated to the integrity of the pile allowing the detection of integrity defects, although these methods do not allow for the characterization of the defect. 1. INTRODUCTION Cast-in-place piles are particularly prone to integrity defects. The reasons for this are multiple, including lack of high quality of contractor workmanship, experience and supervision necessary in construction, variable soil and groundwater conditions on site, etc. Furthermore, visual inspection of the finalized pile is usually impossible. Therefore, special care has to be taken both during the execution process and during the subsequent quality control campaign to detect any defects of executed piles. Today, a lot of methods do exist to assess pile integrity. It is thus essential to understand the mechanism governing those devices to both make an engineering choice of the pile integrity testing method and to interpret correctly the provided results. 2. QUALITY IN PILE FOUNDATIONS 2.1 Pile anomalies A pile having an anomaly is a pile which has a different behavior from what is normally expected. The presence of a pile anomaly does not necessarily imply that a pile cannot be used for its intended purpose (Gordon & Chapman 2004). An anomaly can be considered as a defect, or a “performance” depending on the ability of the pile to fulfil the following three criteria (3C): C1 - Meet the Service Limit State (SLS) requirement and support the proposed working load without settling more than admissible by the superstructure ; C2 - Meet the Ultimate Limit State (ULS) requirement and carry a specified load with an adequate factor of safety against failure ; C3 - Remain durable throughout the design life of the structure such that the pile is not affected by time dependent activities (chemical attack, corrosion of steel reinforcement, ect.), which would jeopardize its ability to maintain its compliance with the first two criteria.

Jan 1, 2019