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By Matthias Pulsfort, Markus Herten, Rolf Breitenbücher, Claudia Fierenkothen

"Secant bored pile walls are frequently used as retaining walls in watertight excavations to cut off ground water aquifers and are subsequently exposed to ground water pressure loading in addition to earth pressure loads. To avoid extra loading from ground water pressure in soils with limited permeability, it can be useful to arrange drainage windows within secant bored pile walls by means of single primary piles filled with porous concrete without reinforcement cages, which usually have to be placed within casings in submerged conditions. This concrete may serve as a horizontal arch between the reinforced secondary piles, but it must however enable vertical draining between load carrying construction beams and the bottom of the excavated pit. In the present submission, the results of several material tests with different mix designs of porous concrete with certain admixtures are presented together with first and important experiences with a wellsuited placement technique for porous concrete casings in small- and large-scale laboratory tests. It can be shown that the usual placement technique of employing a tremie pipe is not suited for this type of unsaturated concrete. Instead, pouring with a particular kind of cone and an open conductor pipe has proven successful.Additionally, special testing methods are currently developed for judging the suitability of the desired concrete mix design in preparation for an upcoming real-scale experimental pile installation in Germany.1. INTRODUCTIONRetaining walls are often built as secant bored pile walls in order to cut off aquifers saturated with groundwater against deep building pits. In soil types with relatively low permeability, however, seepage flow may be permitted, because the quantity of groundwater to be pumped is limited, and the range of influence due to dewatering is not reaching far. Thus, the hydrostatic water pressure on the retaining wall can be considerably reduced, leading to a more economic design (see Fig. 1).In unsaturated soils, the dewatering effect can be achieved by means of porous pervious concrete with a uniform grainsize distribution of aggregates typically placed in a borehole under dry conditions. With regard to the use of porous concrete to be placed at the ground surface in road pavement applications, experience is sufficiently available as shown, for instance, by Neithalath et el. (2010). However placing the porous concrete in a bored pile using a tremie pipe under submerged conditions is a challenge and a completely new approach, because there is a considerable risk of segregation of the fresh concrete, separating the cement lime paste from the aggregates when in contact with water and leaving only neat gravel on the one hand as well as a tight cemented area at the bottom of the pile on the other hand. If this concrete placement is successful, additional dewatering by means of extra wells behind the retaining wall can be avoided. Of course the seepage flow in the adjacent soil needs to be regarded seriously."

Jan 1, 2017

By Almer E. C. van der Stoel

"Abstract This paper deals with assessing the bearing capacity of existing wood pile foundations. With a wide range of restoration projects being performed in the Netherlands, on many locations deep excavations need to be constructed next to existing, many times listed buildings. The building are founded on piles that are often centuries old, so a close evaluation of the remaining bearing capacity, combined with and assessment of the influence of the excavation is in place.After giving an introduction on Dutch pile foundations, a methodology is described to assess the bearing capacity. Aspects as physical foundation investigation, determination of the current bearing capacity and a calculation of the bearing capacity in the new situation are discussed. The results of both analytical and Plaxis calculations are outlined, focussing on how to practically use this approach in renovation projects. Finally, cases studies of the successful application of this approach in major renovation projects in Amsterdam, such as the Conservatorium Hotel and the New Rijksmuseum are used to illustrate the successful application of this approach.A Short Dutch Pile Foundation History (based on Van der Stoel, 2001)The first houses built in Amsterdam, in the 12th century, were very light constructions of timber without foundations. Because of the soft peat layers found in Amsterdam, the houses there suffered from damage due to settlement. In the 13th century, castles and churches were increasingly built of bricks, which made it necessary to provide support for bigger loads. Under the wall of the construction a trench was dug, and this was filled on either side by alder fascines. Between the fascines small wood piles were driven (by hand) on which another series of fascines was put. On top of this construction, were placed oak slabs on which the bricks were then laid. From that moment on, a problem was caused by the decay of wood foundation elements in the humid soil. In 1503 a law was introduced forbidding building foundations on public streets without permission of the Building Inspection (to keep the fronts of the buildings in a straight line). In 1528 a law requiring permission from the local authorities for all building activities replaced this law. In this period developments started which led to the use of the type of foundation that can be considered the mother of the current “typical” Dutch pile foundation. The piles used in this period were shaft- bearing piles about 5 to 7 meters long. The mostly pine piles were driven between oak beams, which were placed on either sides of a trench, after which other oak beams were laid across at regular spaces: the so called “pile bent” pile foundation (Figure 1)."

Jan 1, 2014

By J. Hartikainen

Kemi cardboard mill is founded on the alluvial bed of Kemi river at the north-eastern cost of Botnic Culf in Northern Finland. The alluvium consists of sandy and silty layers underlain by thick medium dense silty moraine layer. The first cardboard machine, having a belt width of 7,4 m, was constructed in 1972 on 7,5 to 9,5 m long wedge-shaped precast driven piles. Because of the excessive differential settlements and sometimes unexpected dynamic malfunctioning of the machine it was decided to strengthen the foundation before installing the partly new machine and increasing the running speed from 500 to 750 m/min. Piling was done under extremly strick limitations concerning space, vibrations, settlements, dust etc. Extra vertical support was made by using 23...25 long x-form steel piles driven by compressed air pile hammer down to rock. The piles were held together with old piles by a conctrete frame with diagonals, which made the total system - machine - foundation frame, piles and ground - ridgid enough to avoid resonance during dynamic loading.

Jan 1, 2010

By Mohammed Sakr

A Two-Section Helical Pile (TSHP) is a steel pipe with two shaft sections of different diameters and with one or more helix plates near the bottom of each shaft section. TSHPs are used regularly in western Canada as foundation pockets for single and double circuit distribution power line poles. The results of a comprehensive lateral pile load test program and the field monitoring of TSHPs installed in organic soil (muskeg) over soft clay are presented in this paper. A total of nine full scale lateral load tests were carried out, including seven tests using TSHPs with different diameters and embedment depths, and two tests using one-section helical piles. The prime objective of the study was to evaluate the lateral resistance of TSHPs installed into very soft organic soil (muskeg) overlying soft clay soils, to compare their lateral resistance relative to one-section helical piles and to compare the measured and the estimated lateral resistances using p-y curves. In order to provide sufficient soil data for analysis, the subsurface soil stratification was evaluated using two different techniques including; Cone Penetration Tests (CPT) and Portable Soil Probe Tests (PSPT). The two testing techniques were also compared and evaluated. This paper summarizes subsurface soil conditions, pile configuration, helical pile installation procedure, testing setup and results.

Jan 1, 2009

By Alexander Filotti, Stanley Merjan

"Abstract. The paper shows the benefits and accomplishments of this relatively new but established product on the pile foundations market in the United States. The first part of the paper describes general aspects of the design, construction, and geotechnical capacity (designed and in situ) of Tapertube piles. The qualities resulting from the design and manufacturing of the Tapertube pile will be presented first.The second part of the paper describes the installation of Tapertube piles for an addition to Terminal One at JFK International Airport and The Edge development. A carbon print analysis for both projects is developed using the EFFC-DFI carbon print calculator. For the JFK project the benefits of using BIM in redesigning the project for Tapertube piles are explored.General description.The tapertube pile consists of a tapered tubular bottom section attached to a conventional pipe extension. The 50 ksi steel for the taper is mechanically folded into a polygonal cross-section (usually 12-sided) with a longitudinal welded seam. The tapers are fabricated in many sizes with bottom diameters varying from 8 to 14 inches, top diameters from 12 to 20 inches, lengths from 10 to 35 feet, and steel thicknesses from 3/16 to 1/2 inch. A conical steel shoe or a flat plate is welded to the bottom of the taper and the top of the taper is circularized to match the outside diameter of the pipe extension. The inclination of the tapers is generally between 1.5% and 2.5%.The pipe extension is fully butt welded to the taper and has the necessary length for the pile to develop the requisite capacity. Concrete fill for the piles is generally 4,000 p.s.i. or more. Typically the piles are shopassembled and shipped to jobsites in lengths to 80 feet."

Jan 1, 2014

By Christian Divis

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Jan 1, 2002

By Dan Brown

Two drilled shaft foundations were subjected to axial load tests in order to measure the influence of drilling fluid on performance. Other than the differing drilling fluids, the shafts were constructed with great care to ensure identical conditions. The results indicate superior performance in both side shear and base resistance of the shaft constructed using a polymer over that of the shaft constructed using bentonite drilling slurry.

Jan 1, 2002

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 N. V. Nayak

Maharashtra State Road Development Corporation Ltd., has initiated a scheme for construction of 55 flyovers in Mumbai in India. To ensure speedier completion of projects several new technologies were adopted to save time without compromising on safety and reliability. Many of the flyovers involved large diameter pile foundations carrying loads ranging from 3500kN to 1375kN. Significant time would have been lost in using conventional load testing procedure to check pile capacity apart from the difficulty in mobilizing the load and the obstruction to site movement and traffic on the adjoining roads. High Strain Dynamic Testing was introduced on the project sites in lieu of static load testing after conducting numerous co-relation studies on various project sites. A total of seven co-relation studies have been conducted till date and based on these data static testing has been replaced by dynamic testing on numerous flyovers. The paper presents the results of such studies. CAPWAP analysis was also conducted on the data to evaluate the percent skin friction and end bearing so as to improve future design parameters.

Jan 1, 2000

By Haijian Shi, Drew Pizzo

This article focuses on the appropriate application of subsurface investigation methods for transmission structures, which are typically designed to resist lateral rather than vertical loads. Currently, the three methods used most often for the subsurface investigation of transmission structures in the field are the Standard Penetration Test (SPT), the Cone Penetration Test (CPT), and the Flat Dilatometer Test (DMT). Each of these methods has advantages and disadvantages, and each is more applicable to some scenarios than to others. To gain a better understanding of these test methods and the implications of using them for various kinds of applications, a comparison study was conducted in the field in Maryland, for three boring locations. Each boring location was explored using each of the three tests as stated. The results of the tests and lessons learned are presented and compared, and these comparisons show that the three test methods agree on the majority of the findings. The results from each test method were also used to derive key parameters such as the soil friction angle for given foundation designs considered in order to establish a clear basis for comparison. Recommendations for performing transmission structure subsurface investigations are made in order to optimize the use of each method and thereby optimizing subsequent foundation designs. INTRODUCTION For overhead transmission structures, the most important structural requirement for determining the foundation design differs from the requirement for other structures such as buildings and bridges in accord with the conditions the transmission structures will need to withstand. In addition to the ability to bear a given vertical load consistent with its use, the foundation must bear lateral loads arising from wind and other weather conditions. The foundation types used most often for overhead transmission monopole structures include concrete drilled pier, vibratory caisson, and direct embedment. In order to determine an appropriate and even an optimum foundation design for any given set of conditions, an appropriate subsurface investigation method or approach is needed. Currently, the standard penetration test (SPT), the cone penetration test (CPT), and the flat dilatometer test (DMT) are the three most commonly used subsurface investigation methods.

Jan 1, 2018

By Claudio Olalla

This paper relates to the foundation of a steel structure located at the San Martin de la Vega (Madrid) amusement park. The structure has more than 100 supports with various loading conditions, including important horizontal and uplift forces. Additionally, the settlement tolerances are very strict. A massive gypsum formation with interbedded clay layers and random solution great voids at various levels constitute the soil. The foundation design has been conditioned large enough these difficulties (load conditions and soil problems). The piling machine used was powerful to drill through the soft rock (UCS up to 11Mpa). The integrity of each pile had to be guaranteed by continuous recording of drilling and concrete pouring parameters. In order to fulfil all those conditions, a STARSOL type-piling rig was used. More than 4500 meters of piles were performed. The diameters of the piles were 450 and 550-mm and their depths varies from 6 to 23 meters. All piles were reinforced over their full length.

Jan 1, 2002

By Mark M. Petersen

As part of the addition of eight new combined cycle generating units at the Florida Power & Light Sanford Plant, 2,129 piles were to be installed. The existing plant elements were supported on driven piles, and the variation in pile lengths during previous work, as well as available subsurface information, indicated a complex stratigraphy. At the request of the owner, the designer/construction manager developed a program to evaluate the use of pressure-grouted displacement piles. A pre-design load test program in areas that represented the apparent extremes in subsurface conditions indicated that the system was feasible; however, the presence of existing features that were to be demolished later precluded the clear delineation of subsurface conditions in advance of construction. A contract was negotiated with the pile installer based on the best estimate of potential pile lengths, with modifications to pile lengths to be set based on additional exploration. A total of 52 cone penetration soundings and five load tests were performed immediately prior to and during pile installation to establish correlations between the CPT data and pile performance. Pile depths were set based on these correlations. Pile installation was completed 6 weeks ahead of schedule and 15 percent under the original budget estimate. This paper documents the evaluation of pressure-grouted displacement piles as an emerging technology, and illustrates the benefits of a close working relationship between the owner, designer, and pile contractor at a site with variable subsurface conditions.

Jan 1, 2002

By Ray Schmahl

The Glenwood Canyon is a 13 mile long river gorge formed by the Colorado River approximately 2 miles East of Glenwood Springs, Colorado and approximately 150 miles West of Denver Colorado, (See Drawing #1). The canyon walls rise some 800 feet from the river elevation on either side of the river. The South-side river bank is occupied by the Denver and Rio Grande Western Railroad. The Northside is currently occupied by completed sections of Interstate 70 and US Highway 6. The railroad was built in the late 1800's and a hydroelectric power generating station was built in about the center of the canyon in the early 1900's. The Highway 6 platform was completed in the 1930's. The design and alignment for Interstate 70 thru Glenwood Canyon began in the early 1970's. The Highway thru Glenwood Canyon was designated a scenic Highway by the United States Congress, thereby allowing certain deviations from standard Interstate requirements. Environmentalists objections to the construction of Interstate Highways thru Glenwood Canyon resulted in especially careful design to avoid adverse environmental impacts. As a result, in many areas the new Highways will have restored the canyon to its more native configuration than what was the case in the building of the US 6 Highway platform.

Jan 1, 1990

By A. R. Dover

The Richmond-San Rafael Bridge is a 6.92 kilometer (4.3 mile) long major toll bridge span that crosses the northern San Francisco Bay in a highly seismically active region. Tutor-Saliba / Koch / Tidewater JV was contracted by Caltrans to conduct a comprehensive seismic retrofit. The JV provided geotechnical planning and quality control services as described herein, under normal oversight by Caltrans. Part of the robust foundation retrofit design included the installation of 26 new, large diameter piles, including eleven 3.81 m (12.5 ft) diameter, cast-in-drilled-hole (CIDH) marine piles that were drilled 9.15 m (30 ft) into the bedrock beneath the Bay, where the water depth ranged up to about 21.3 m (70 ft). These reinforced concrete-filled composite piles have a steel shell permanent casing from the bridge substructure pile cap through the water column and 30.5 to 39.6 meters (100 ft to 130 ft) of marine sediments to the top of rock. This paper discusses construction, inspection (ranging from the QA employed in the planning of the CIDH pile installation methods and equipment to the actual construction inspection required for the routine installation of the shafts), problems that were encountered during construction, and the solutions that were developed and implemented. Inspection, particularly with the usual difficulties in the marine environment, coupled with the difficult and complex bedrock conditions was particularly challenging, and ranged from non-destructive testing to "in-water, inshell" diver inspection. Similarly, the complexities of dealing with both the steel casing "riser" and the associated drilled shaft (rock socket) portion of these composite foundation elements created some unusual issues. The paper also presents important lessons learned from the project.

Jan 1, 2008

By Jacob Chacko

The east span of the San Francisco-Oakland Bay Bridge (SFOBB), which is one of the most heavily traveled bridges in the world, will be replaced due to seismic safety concerns. The majority of the new bridge will be founded on large-diameter (1.8 to 2.5 meters), approximately 60- to 100-meter-long pile foundations The large-diameter steel pipe piles and soil conditions are similar to those used/encountered in many offshore structures. Thus, the design methods used are based on site-specific modifications to the procedures recommended by the American Petroleum Institute rather than the conventional procedures that have been formulated and used for the design of much smaller piles. Pile foundations will experience their maximum loads during the design earthquake. For the Safety Evaluation Earthquake, tension loads of up to approximately 80 to 90 meganewtons (MN) and compression loads of up to approximately 120 to 140 MN were calculated. Due to the economic importance of the SFOBB and the consequences of catastrophic failure in both economic and human terms, the design and analysis of the pile foundations supporting the bridge consider a number of aspects of pile-soil behavior that are normally ignored. Those aspects include: 1) the effects of consolidation and setup, 2) the behavior under dynamic loading, 3) the losses of resistance under cyclic loading, and 4) the load-settlement behavior of the piles under severe cyclic loading conditions. Since the treatment of complex aspects of pile foundation behavior is not codified in any guiding documents, several project-specific methods were developed for design and analysis of the foundation piles.

Jan 1, 2002

By James J. Cahill

Contractor's working in an urban environment face a multitude of working conditions. There is no typical "Downtown" job site. From afar we just see the skyline, or up close a specific building. This, of course, does not give us a clue as to the site conditions the foundation contractor faced in doing his work. The open, downtown building site is still available on some projects, but they are becoming rare as our cities are becoming more developed. A typical site today might include any one or several of the following problems: A. Deep pit with no ramp access B. Multi-type known or unknown obstructions C. Height limitations D. Load restrictions E. Existing adjacent building founded on shallow foundation F. Existing foundations G. Existing tunnels, utilities or subways

Jan 1, 1991

By Kul Bhushan

This paper presents the results of lateral load tests on 0.61-m to 1.27-m (24 to 50-inch) diameter drilled and cast-in-place piers in San Diego area residual/formational soils. The test piers were installed and tested in the following soils: Decomposed Granitic Rock (Ktd), Stadium Conglomerate (Tst), and Friars Formation (Tf). Lateral loads of up to 845 KN (190 kip) were applied to the piers in residual granitic soils, and loads up to 1780 KN (400 kip) were applied to the piers in Stadium Conglomerate and Friars Formation. The tests were conducted by jacking against adjacent piers and monitoring the lateral load and lateral deflection at the ground line. Test results indicate that ultimate lateral pile capacities of up to 1800 KN (400 kip) can be obtained for 0.61 m (24-inch) drilled piers with penetration of 3 to 6 m (10 to 20 ft) in the residual/formational soils tested. Lateral load analyses using p-y curves for very dense sand significantly overestimate the observed lateral deflections. For lateral load analyses using dense sand p-y curves, p-multipliers that increase the lateral soil stiffness (p-y curves) by 2 to 8 times are required to match the load-deflection behavior measured in the test piles. When applied to the dense sand p-y curves, the p-multipliers provide a more accurate prediction of load-deflection behavior in the residual/formational soils, and can result in shorter required pier penetration and significant savings in foundation cost.

Jan 1, 2002

By Lance A. Roberts

Micropiles are commonly utilized for applications other than foundation retrofit. In bridges, for example, micropiles can serve as the permanent foundation elements or can be used in temporary support applications. In this paper, a case study on the use of micropiles for the 18th Street Expressway Bridge rehabilitation/repair project in Kansas City, Kansas is presented. In the project, micropiles were utilized for support of six temporary jacking structures, which allowed the bridge to be lifted while repairs were completed. A group of six micropiles was required to support each jacking structure. The required compressive service load per micropile was approximately 300 kips (1300 kN) and the settlement of the micropiles under the service load was to be limited to 0.5 in. (12.7 mm). Two field compression tests were conducted as part of the project. The field load test data was integrated within a soil-structure interaction capacity approach in order to analyze and permit the shortening of the design bond length for the production micropiles.

Jan 1, 2009

By Priyadharshini M. R., Premalatha K

"Abstract With the development in the construction of heavily loaded structures, the necessity of pile foundations has increased. For the transfer of heavy loads, it is mandatory that the piles need to be socketed in the underlying rock strata. The load transfer in bored rock socketed piles is by end resistance or the combination of shaft and end resistance which in turn depends on the length of the rock socket. The determination of socketing length of the pile at present is mostly based on a few factors which affect the pile load transfer mechanism. The effect of all the possible factors involved, need to be studied in proposing guidelines for the design of rock socketing length of the pile. Analyses are carried out using finite element analysis software (PLAXIS 3D Foundation) to understand the influence of the thickness of overlying strata for different socket lengths of piles in weak rock. From the load settlement curves, the influence of the overlying soil on the rock socket length isobserved and an effective rock socket length is proposed.IntroductionThe determination of socketing length of the pile at present is mostly based on a few factors affecting the pile load transfer mechanism, which sometimes give a better design and sometimes an uneconomical design. Too much socketing length results in more construction time and higher costs. Therefore, the effect of all possible factors involved need to be studied in proposing guidelinesfor the design of t h e r o c k socket length of the pile.The factors that affect the termination criteria of the rock socketed pile are the capacity requirement, thickness and properties of the overlying soil, characteristics of the founding strata, drilling tools used, roughness of the rock socket and nature of loading.A comprehensive study was performed to understand all the above mentioned factors in different types of rocks. In this paper discussion is made on the settlement results, specifically the influence of overlying sand of different densities above a weak rock. The influence of stress developed is not discussed, keeping in mind the size of the paper under study."

Jan 1, 2014

By Michael Quadagno

Hudson River Pier 86, home of the historic USS Intrepid Aircraft Carrier and the Intrepid Sea-Air-Space Museum, is currently undergoing a $30M reconstruction. This project involves the demolition of the old timber pile supported pier and construction of a new 150 ft wide by 782 ft long concrete pier, built over the footprint of the old piles. The new pier consists of steel pipe piles, precast concrete pile caps, and a composite deck, made up of precast, prestressed concrete planks and cast-in-place concrete topping. This paper focuses on both the structural design and construction of the new pier, with emphasis on the pile foundation. Pier 86 is unique in that it is required to resist the extremely high lateral loads imposed on it by the permanently moored 898 ft long aircraft carrier during severe storms. A total of 360 steel pipe piles support the new pier. These piles, which are 24 in. in diameter and range in length from 58 ft to 175 ft, were driven down to bedrock. The piles, each having 200 ton allowable capacities, work together to resist the significantly large lateral loads exerted on the pier by the ship. The installation of the piles was unique in that all the piles, including the ?super-longs?, were fabricated to-length offsite, delivered to the site via truck and barge, and installed in one piece, eliminating the need for field splicing. The Pier 86 reconstruction will be completed within an extremely aggressive 18 month schedule, from January 2007 through June 2008. The refurbished aircraft carrier Intrepid will return home in September 2008, and the grand re-opening of the pier will be on Veteran?s Day 2008. This paper provides a case history for owners, government agencies, engineers, and construction professionals that will be faced with the challenges of designing and building new piers.

Jan 1, 2008