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By Charles Pol Vuillier

Piling work for modification to the Charles Grimes Bridge in Melbourne, Australia required piles to be installed through 15 to 20 m thickness of very soft to soft silty clay overlying 10 m of stiff clays and sands in turn overlying siltstone. The presence of an old sewer founded at depth in the soft clays demanded that vibrations be kept to a minimum. Two pile type were used by Vibro-pile (Australia) to provide the client with the most economical piling price. The two pile types were CFA piles of 750mm diameter founded in the weathered rock and a full displacement concrete injected screw pile developed by Vibro-pile called the "Z" pile, founded on the rock. The development and features of the "Z" pile are briefly discussed, including the perceived applications and advantages of the pile type. On board instrumentation comprising a computer was used to monitor all aspects of the construction. The rig instrumentation provided an important quality control measure that gave confidence in the pile installed. Pile performance was proved on the cast in situ piles by dynamic load testing methods. Initially tests performed with a 120 kN drop hammer, which was not capable of mobilising the required loads. The performance was then satisfactorily proved by using a drop hammer of 20 tonne mass delivering blows drop heights of 1.5m. Low strain integrity tests on a number of piles were also used to confirm the structural integrity of the piles.

Jan 1, 2000

By Eric C. Halpin

"1. Introduction and Backgrounda. In its fundamental form, risk is simply the likelihood of an adverse impact. Expanding on this theme, the Corps of Engineers has broadly defined risk associated with infrastructure as a factor of three distinct elements: a probabilistic assessment of a hazard such as a flood or earthquake; a probabilistic assessment of how the infrastructure performs in the face of this hazard; and a measure of the likely consequences – loss of life, economic damage, environmental impacts – associated with the resulting inundation scenarios.b. The lessons and observations described herein relate to the Corps of Engineers experiences in implementing risk concepts for infrastructure management during the period 2005 through 2013. The Corps of Engineers is a large, decentrally operated and centrally led federal agency that plans, designs, constructs, operates, maintains, and/or manages a portfolio of over 3,000 built dam and levee systems within the United States. The infrastructure in this portfolio is 55 years old on average, and although much of the structures provide for flood risk management benefits, many of the dams deliver multi-purpose benefits. Scale matters – where scale and uncertainty are large, risk concepts provide great opportunity and arrangement for application.c. The amount of organizational change that is demanded for the implementation of risk concepts is considerable and should not be under estimated, but need not be feared if the path others have taken is considered. This paper is, in many ways, an opportunity to step back from the last seven years of implementing risk informed management, check our own azimuth and maturation, and share the purpose and energy behind our own continuing actions. Hopefully, this azimuth check is also beneficial to those that are either considering the use of risk or are in the process of implementing risk concepts.d. Success at managing the massive change related to incorporation of risk concepts will directly affect success of the infrastructure program. The three key organizational elements to consider –human systems such as governance and competencies; policies that outline the who, when, and why of decisions and management; and the processes and technology that outline how work is to be performed - are changed fundamentally. From senior leaders to project team members and all of the people in between, there is a need to discuss, confront, and vet the change and the role people and organizations have in the process. For the Corps of Engineers, with a history of over two centuries, deeply embedded beliefs about infrastructure aren’t transformed over night - the change process is decadal in scope. Given our self imposed “project execution” mantra and corporate objective, risk seemed threatening at first to the cost and schedule of delivering infrastructure projects. In reality, risk concepts have been responsible for savings and cost avoidance of nearly $6 billion over the last three years alone while at the same time justifying increased investment by several fold for the highest risk needs."

Jan 1, 2014

By J. A. Elliot

Deep Mix-in-Place soil stabilisation is achieved by forming columns of soil/cement arranged to overlap by secant intersection. Alternate columns are constructed initially and infilled. The cementitious material injected is designed to retard the strength of the resulting mix thereby allowing satisfactory overlapping. Columns are constructed using a designed large diameter mixing auger mounted on a smaller diameter auger stem. This is firstly screwed to the design depth removing only such spoil as to enable penetration of the auger, and subsequently counter rotated and extracted in a predetermined mixing pattern and grout injection rate to ensure continuous and homogeneous treatment through each successive level. The process is performed whilst monitoring auger depth, grout flow and pressure. Cementation Piling and Foundations Limited used this technique to stabilise allu­vium and to facilitate the construction, by conventional techniques, of a circular pumping station pit of 10M diameter to 10M below ground level. The work was carried out within 3M of adjacent domestic properties, and on a very restricted site in Elland, West Yorkshire. Ground conditions consist of 2M of cohesive alluvium becoming water bearing and increasingly sandy and gravelly with cobbles which overlies the mudstones at 10.0m depth. Sandstones beneath formed an aquiclude to artesian ground water with the underside of the open excavation approxi­mately 1.0M from the top of this material. Peripheral treatment into the mudstone, coupled with pressure relief wells, proved successful and final excavation depth was achieved in "the dry".

Jan 1, 1989

By Kouichi Tomisawa

Two bridges were constructed for extension work of Central Hokkaido Connection Road in 2005 at two different sites. Pile group foundations were employed for the foundations of abutments of the two bridges. In order to assess the performance of the constructed piles in the sites and to obtain design parameters for design in future, static alternating cyclic horizontal load test was carried out on one of the open-ended steel pipe piles constructed at each site. The ground at one site was characterised as a thick deposit of volcanic soils, and the ground at the other site was characterised as a very soft peat layer near the surface. In this paper the results of static alternating cyclic horizontal load tests on the piles at the two sites are presented and discussed in detail.

Jan 1, 2006

By W. G. K. Fleming

The general history of piling is traced up to the present time with regard to the evolution of methods and materials. The processes have been strongly influenced by developments in basic equipment and industrial change. It is noticeable that in the twentieth century more progress has taken place than in the many previous centuries. It has been strongly influenced by the general development of Soil Mechanics. Test loading is probably the most effective way to assess the success of designs and many empirical relationships have been challenged through it. As we approach a new century it appears that it will be an age of rapid equipment development, with much enhancement of understanding of what has been done. Processes of automatic construction and testing will becoming commonplace. These changes will narrow the limits of conventional scatter that have come to be accepted and to a large extent will be driven by political efforts to curtail energy consumption, to raise standards of quality and reliability, and to conserve the environment. 1. Ancient history. Piling is an ancient art. Its first mention in history is from Herodotus, the first person to commit an account of his times to the written word in the years 557 to 479 BC. He evidently had a strong interest in engineering matters because he wrote of building, brick making, reinforced brickwork, river training, canal building, bridge construction, tunnelling and its acoustic detection and piling. The piling reference comes from Book 5 at paragraph 16.

Jan 1, 1999

By Jon H. Gould

This paper describes the following at the new Advanced Solid Rocket Motor (ASRM) nozzle manufacturing facility, which is being constructed inside an existing manufacturing facility: 1) generalized subsurface conditions, 2) pile load test program and evaluation, 3) pile selection, 4) problems associated with pile driving operations, and 5) production pile installation. The poor subsurface conditions, known and unknown underground obstructions, and work environment inside the existing building, used to manufacture the Space Shuttle external fuel tanks, required special pile installation equipment, procedures, and work schedules to install the economical pile foundation system ahead of schedule and without a lost time accident. GEOTECHNICAL STUDIES In April and May 1990, 16 soil test borings were drilled inside the existing building with a truck-mounted drill rig. The borings extended to depths ranging from 60 to 65 ft (18.3 to 19.8 m) below the floor slab. Typically, the silty and clayey soils were sampled by pushing "undisturbed" Shelby tubes, and the more sandy soils were sampled by driving a Standard Penetration Test (SPT) split-spoon sampler. The unconfined compressive strength, water content, and unit weight of the Shelby tube samples were measured in the laboratory. A geotechnical report was issued in May 1990 presenting the results of the field and laboratory testing and foundation recommendations (Gilbert, 1990).

Jan 1, 1992

By Gordon Demetrick

3900 Yonge St. was not a typical site on which to build a condominium apartment. A steep hill covered the majority of the site. In order to use as much of this site as possible, the rear of the building was to have nine stores cut into the face of the hill. A permanent shoring system was required as the building structure was not designed to provide sufficient stabilizing elements to support the total earth pressure. The total excavation depth required was 36 m (120'-0") with the upper 12 m (40'-0") to be backsloped. The vertical face of soil to be supported was 24 m (80'-0'). The shoring system originally designed by the Structural Engineer was to support this face by installing soldier piles and inclined earth anchors. During bid preparation it became evident to us that the system as designed would be difficult and expensive to install due to wet soil conditions. An innovative design was required to overcome these problems. Anchor Shoring hired John Stephenson Consultants Ltd. to aid them in accomplishing this goal. After extensive investigation together with The Trow Group, a unique design was proposed which provided a practical solution to the shoring problem.

Jan 1, 1987

By Mary C. Nodine, Michael P. Walker, Paul Eggers, Donald E. Aubrecht

The CANALSIDE commercial development in Buffalo, New York serves to revitalize the former site of the Buffalo Memorial Auditorium, adjacent to Lake Erie. The Auditorium was constructed in 1940 and founded on steel H-piles driven to limestone bedrock. After decades of professional sport and entertainment events, the “Aud,” as it was locally known, was closed in 1996. It sat vacant until it was demolished in 2009, at which time plans were made to revitalize the area with shops, restaurants, and a historic replica canal. The only portion of the Aud that was left intact was a subbasement boiler room. The subbasement was renovated in 2014 and has since been used to house water and ice making equipment for the historic replica canals, which boast recreational ice skating in the winter. The subbasement floor was about 10 feet below groundwater and the Lake Erie water level. The floor consisted of an approximately 4-foot-thick layered inverted waffle slab system, with reinforced concrete grade beams and concrete infill between the grade beams. A waterproofing membrane was located near the base of the slab. There were no major seepage issues in the subbasement, so the existing waterproofing membrane was assumed to be intact and performing adequately. A four-story building housing a children’s museum was proposed to be constructed directly above the subbasement. The loads imparted by the new building would exceed the capacity of the existing piles, so it was determined that drilling micropiles through the subbasement floor would be the most practical means of supporting the new building. Drilling through the existing slab and waterproofing system was a concern due to the challenges of controlling water during construction and the importance of maintaining the integrity of the permanent waterproofing system.

Jan 1, 2018

By Han Xuanjiang

Through whole analysis of static testing piles information of a teaching building, this paper put for ward that when the ratioes of unload rebound amount to residual deformation and to total settlement reach the maximum, the testing load is selected as allowable capacity of single pile by camparing with the settlement in the practical engineering, it is proved that this method fits to practice, for other several projects, its also available. Therefore non-destructive testing pile method was improved, so all the tested piles can be reused as engineering piles.

Jan 1, 1991

By Frederic Masse

With widespread acceptance in the market place, many engineers are choosing ground improvement techniques to provide suitable foundation subgrade at sites that would have traditionally required deep foundations. This paper discusses the Controlled Modulus Columns (CMC) ground improvement technique and some case histories highlighting the use of this technique for retail development sites. CMC are a sustainable and cost-effective ground improvement technology that transmit load from the foundation to a lower bearing stratum through a composite CMC/soil matrix. The CMC installation is also an attractive option from an environmental perspective because it utilizes reverse flight augers, which displace the soil laterally. This installation technique achieves two goals: it densifies the soil around the CMC, which improves load transfer into the element and avoids spoil and its disposal. Through the introduction of two cases histories, we will present the key benefits of the CMC technology. Each case history will clearly illustrate how a CMC solution can reduce the overall cost of a project when compared to a more traditional type of deep foundations. They will also show how the use of CMCs has benefits that relate to the overall sustainability of the project. While CMCs are an attractive financial and sustainable option, they have also demonstrated that the performance of the system is comparable to that of deep pile foundations. Because CMCs are a relatively new technology many potential users are not aware of its benefits. While we discuss the use of CMCs to support buildings in this paper, CMCs also have been used for a variety of other applications including foundations for tanks, mechanically stabilized earth (MSE) walls, and embankments

Jan 1, 2011

By Dan Brown

This paper presents a case study of a cyclic lateral pile load testing program performed on two 18-in square prestressed concrete piles (PSC) in Savannah, Georgia. The load test program was developed to simulate the lateral behavior of a single pile under seismic loading conditions for the design and construction of a large LNG storage tank. The lateral load tests included cyclic loading to measure possible degradation in soil response followed by static loading to large displacements (around 6 inches at the loading point). The lateral load was applied through a reciprocating jack positioned to push and pull the piles against each other. The test piles were instrumented with multiple displacement transducers, downhole inclinometer, and strain gauges. This paper provides an interpretation of the test results regarding the pile performance and soil response to monotonic and cyclic lateral loading. A backfitted computational model of the soil resistance was developed to match the test results using the LPILE computer program. The load-deflection and deflection/moment versus depth comparisons suggest that this model appears to capture the behavior relatively well within the general range of suitability for design purposes. New design curves were developed based on the soil parameters derived from the lateral load test results.

Jan 1, 2003

By K. Viking

The vibratory characteristics of full-scale sheet piles, vibratory driven into the ground, have so far not been described systematically in detail. This paper concerns the preliminary results of a series of full-scale field tests where both the driveability and induced ground vibrations have been continuously monitored. Furthermore, the results of measured ground vibration levels have been measured at two different sites characterised as having hard and easy driving conditions. In the light of the presented results, the paper briefly discusses how the complexity of a driveability and vibration prediction can be subdivided into three parts, namely, vibrator-, sheet pile-, and soil-related parameters, all of which significantly affect both the driveability and induced ground vibrations.

Jan 1, 2000

By Samer R. Rabab?ah

As part of the PHX Sky TrainTM project at Phoenix Sky Harbor International Airport in Phoenix, Arizona, the existing traffic lanes at the 44th Street underpass below the Union Pacific Railroad (UPRR) Bridge will be shifted to accommodate the people mover guideway. The proposed reconfiguration and reconstruction of 44th Street required the utilization of micropiles and permeation grouting to resist the lateral forces induced by cutting into the slope below the existing bridge abutment footing. This paper discusses the evaluation of the existing bridge abutment, including analysis of the original foundation system, and design, installation and testing of a new micropile-supported retaining wall to support the cut slope below the existing bridge abutment foundation. A monitoring program was implemented during construction to evaluate the short- and long-term performance of the bridge abutment. Instrumentation included survey monitoring points, inclinometers, tiltmeters and crack gauges. A micropile load testing program was conducted to verify design assumptions concerning micropile axial and lateral loading. Numerical analyses (using PLAXIS software) were performed to predict the short- and long-term behavior of both the abutment wall and the bridge foundations. Movement data collected from the monitoring program indicate that the wall and bridge foundations are performing satisfactorily and within the general bounds of predicted movements. The results from the numerical modeling using PLAXIS software showed that the proposed solution is deemed adequate to provide the needed global stability with an acceptable factor of safety, along with acceptable deformation.

Jan 1, 2011

By Mark R. Svinkin

Construction vibrations may adversely affect surrounding buildings and their effects range from human discomfort and disturbance of sensitive devices to visible structural damage. There is no unique conclusion regarding the effect of construction vibrations at every site. Measurement is usually made to monitor vibrations and control them with the vibration thresholds for disturbance of sensitive objects as well as damage to structures. To prevent potential litigation and mitigate the vibration effects on sensitive devices, people and structures, it is necessary to manage and minimize vibration problems before the beginning of construction activities or installation of vibrating machine foundations, and during construction. Pre-construction damage survey and engineering vibration investigations, including the prediction of anticipating vibrations, have to be made at most construction sites in advance of construction activities. Vibration monitoring and control have to be provided during construction. The instrumentation feedback of vibration prediction, monitoring and control provide the basis for choice of measures to prevent or mitigate vibration problems and settlement damage hazards.

Jan 1, 2002

By K. Kawakami

In Japan, pile foundations have been used extensively for buildings, bridges and port facilities. A large number of steel pipe piles were first used in the 1960's and the amount of steel used in foundations increased by 1973 to one million tons. This report describes current practice in the actual use of large diameter and long steel pipe piles in Japan, related to their performance: including consideration of pile size, hammer types used for driving the results of field tests measuring stress occurring in the piles and the driving formulae currently being used in practice in Japan.

Jan 1, 2010

By Onur Kacar

A numerical approach has been implemented to assess the settlements of pile groups bearing in clay. A three-dimensional finite element program has been utilized to model a vertically loaded spread footing, a single pile and a pile group. The soil-pile interaction was modeled with elastoplastic soil and interface elements. The model has been calibrated using a full scale load test results of the spread footing. The load transfer between the pile cap and the piles was assessed and compared with the measured load transfer. The predicted settlements for the pile group were compared with the settlements measured in the load test. Two analytical methods were adopted to predict the pile group settlements and they were compared with the measured values. The group effect determined from the analysis and load tests was compared with the interaction factor approach. It was shown that three-dimensional finite element approach can be successfully utilized to assess the soil-structure interaction and hence the load transfer between the piles and pile cap. Also, it was shown that the interaction factors method and equivalent footing method work well in the working stress range, however they underpredict the settlements at larger loads. INTRODUCTION The settlement and stress distribution of pile groups have been traditionally estimated based on load test results of single piles and accounting for the group effect using various approaches. The most widely used approaches are group interaction factor method, equivalent footing method and equivalent pier method. These approximate solutions are used very commonly in practice as full-scale load tests on pile groups are very expensive and time consuming. These approximate solutions are also adopted in design guidelines such as AASHTO LRFD Bridge Design Guidelines (2014) and FHWA Design and Construction of Driven Pile Foundations (2016). In this paper, a full-scale foundation load tests performed by Nagai et al. (1961) and reported by Koizumi and Ito (1967) is modelled using a three-dimensional numerical method. The settlements and the stress distribution on foundations were then compared with the traditional equivalent footing method and interaction factor methods.

Jan 1, 2018

By Rüdiger Wunsch

The new high speed Vienna - St.Pölten line and the Lainzer tunnel are to be connected to the existing Western railway line in Vienna. This involves building an underground cut and cover branching tunnel which will be connected to the Western railway line by ramps. A key structure is the Herzmansky Street tunnel, which has a length of some 820m. It is to be constructed as a cut and cover tunnel using the top down method. The walls of the tunnel are designed as a water resistant structure consisting of double walls, an outer wall of bored piles and an inner reinforced concrete wall. The bored pile wall will be used as a temporary retaining wall during the construction phase and will also be a structural part of the per­manent tunnel wall. The retaining walls of the open pit, which will have a depth of up to 14m and a width of 12m, were investigated as a non-contiguous bored pile wall and overlapped bored pile wall. Preventing ground water from penetrating into the pit is of paramount importance. The high ground wa­ter level is the determining factor for the dimensioning of the bored pile wall and results in the require­ment for a water resistant concrete structure. It has been necessary to adopt adequate measures, therefore, in order to reduce the hydrostatic water pressure during the construction phase, assuming economical pile dimensions.

Jan 1, 2000

By P. A. Neill, O&apos

The caisson foundation for Vent Building No. 6, at the southern landfall of Boston's Third Harbor Tunnel, was installed inside an unbraced concrete cofferdam 250 feet in diameter and about 70 feet deep. As a spectacular engineering feat, the cofferdam itself certainly ranks first. However, the foundation work within was no routine caisson job and made its own contribution to the state of the art. Comprised of 5 ft. diameter caissons socketed 10 to 16 feet in sound rock, it posed serious challenges in logistics, space limitations and time, requiring development of unique, purpose-made equipment. The unexpected discovery of significant depths of shattered rock overlying acceptable sound rock, along with other surprises of lesser import, compounded the problems. How these challenges were planned for, met and overcome is the subject of this paper.

Jan 1, 1994

By Brock Wallis, Steve Davidow

The following text will present the concept of rock socketed drilled shafts used to support electrical substation structures, and discuss the cost and schedule risks that traditional design responses to unforeseen shallow rock can pose to a project. Design considerations will be detailed, including rock characterization, shear strength of drilled shafts, and modeling lateral resistance of the shaft and surrounding rock. The specific case of drilled shafts installed for heavily loaded structures at the Moxie Freedom Substation will provide an example of how close collaboration between the engineer and contractor to refine designs based on site-specific feedback can provide tangible benefits to the project. In this example, value engineered designs resulted in an approximate 40% reduction in shaft/concrete volume and a 60% reduction in total rock socket depth. PROJECT OVERVIEW The Moxie Freedom Project included the construction of a new 500 kV switchyard in Berwick, Pennsylvania. The foundation contractor was selected to install both small and large diameter drilled shaft foundations to support the structures within the switchyard. The small diameter shafts were utilized to support transformers, switches, bus supports and a static mast, while the large diameter shafts were used to support one 180-foot monopole and six H-Frame structures. CHALLENGES: ROCK SOCKETED DRILLED SHAFTS Available geotechnical data at the time of bid included limited borings and seismic refraction. The borings were not located at every structure, and the contractor and design engineer were left to interpret desktop studies and geophysics to determine the probable site-specific conditions at each foundation. The data suggested substantial variability in the quality and depth to bedrock across the project area, indicating significant risk of deep embedment into bedrock at all seven large diameter shaft locations. Rock socketed drilled shafts pose unique challenges for both designers and contractors, and the topic has become a focus of national foundation organizations. Traditional design models result in deeper and/or larger diameter shafts where rock is encountered. In the case where site-specific geotechnical conditions are not clearly understood and rock is encountered at shallow depths, this can lead to significant additional rock drilling, impacting overall project cost and schedule. Rock drilling can result in more than ten times the cost of soil drilling and can easily take in excess of ten times longer to excavate.

Jan 1, 2018

By Jelke Dijkstra

This paper presents the results of model pile load tests in a photoelastic material. The soil in this test is represented by an assembly of photoelastically sensitive glass particles, which allows for optical measurements of stresses. In the same test setup, displacements around the pile are measured using digital image correlation (DIC). During the pile installation stresses and strains are recorded. Tests were performed in loose and medium dense particle assemblies. The development of stresses and strains around the pile tip and pile shaft are quantified and presented in this paper. For the loose conditions the results show a small influence on the stress state. For the medium dense conditions a clear stress change is observed.

Jan 1, 2006