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By John E. Lens

Minutes after the Friday afternoon October 16, 2009 announcement that the 80 year old Lake Champlain Bridge was closed to traffic out of concern for public safety, emergency detour planning started at VTrans and NYSDoT. The closure severed a cross-lake link between Addison, VT and Crown Point, NY, which created a 76 mile detour and significant hardship for commuters, farmers working on both sides of Lake Champlain, and businesses relying on both traffic and employees commuting between Vermont and New York. Rehabilitating the bridge was determined to be economically and technically unfeasible and the design of a replacement bridge was accelerated for a spring 2010 construction start. In the meantime, a temporary ferry alternative was to be rushed into service beside the original bridge by February 2, 2010. This paper presents the case history of the fast-tracked ferry dock design and construction on the Vermont side. Twin 300-foot-long pile supported approach spans, a loading slip system and ice deflectors were designed, fabricated and constructed in 90 days in the fall/winter of 2009-2010. This chronicles the project from initial concepts through the extraordinary cooperation between state and federal agencies, and near round-the-clock winter construction on Lake Champlain. This project and its companion project on the New York shore succeeded by virtue of exceptional cooperation between seasoned regulatory, design, and construction participants and warrant this case-history presentation of the Vermont project to share within the industry as an example of overcoming extraordinary challenges.

Jan 1, 2011

By Anthony D. Barley

Over 60,000 multiple anchors have been used internationally since their introduction in the early 1990s, including 1000 in the United States. The multiple anchor system comprises a "multiple" of "unit" anchors installed within a single borehole - each unit anchor being staggered within the borehole length to mobilize its own capacity independently of the other unit anchors. These systems offer higher capacity than conventional anchors with identical bond lengths due to superior load transfer efficiency. The use of higher capacity anchors may allow reduction in the number of anchors required on a project, which results in time and cost benefits to the anchor installer, contractor, and the owner. Fully removable temporary multiple anchors are available, and have been used with consistent success. Three case histories are discussed highlighting the use of these systems

Jan 1, 2002

By Dimitrios Polantzas P. E., Collin E. Sweeney E. I. T., Franklin M. Grynkiewicz P. E., Leili Javidanian P. E.

In the latest AASHTO design specifications, the Load and Resistance Factor Design (LRFD) method is prescribed for the design of retaining walls. However, inconsistencies arise when LRFD is used for retaining wall design versus the traditional Allowable Stress Design (ASD). Required toe embedment and wall loading demand vary greatly when the two design approaches are compared, all else being equal. This is due to application of linear load factors to properties that vary non-linearly in the design. These inherent inconsistencies are further intensified when introducing factors such as layered soil profiles, different wall types, groundwater elevation, and surcharge requirements. When applied correctly, these two design approaches, in theory, should lead the designer to the same result with little discrepancy, as they do with steel structure design. However, the use of the current AASHTO LRFD method for various geostructural retaining wall designs yields contradictory results that suggest existing retaining walls that have been successfully designed and constructed are unstable. Fundamentally, LRFD should be built on reliability-based calibrations; the successful past performance of existing retaining structures designed using ASD suggests that the LRFD approach requires considerable modification. The authors of this paper recommend that the current LRFD load factors be reviewed and revised based on more comprehensive wall performance data and wall type such that the difference between retaining structures designed using LRFD and those designed using ASD is eliminated.

Oct 1, 2022

By Jim Glider, Noah Miner

The Gordie Howe International Bridge is a project to build a cable-stayed bridge and border crossing across the Detroit River. With a span length of 2,800-ft (853.4 meters), the Gordie Howe International Bridge will have the longest main span of any cable-stayed bridge in North America. Each tower has two legs that are supported by six drilled shafts each for a total of 12. The tower shafts are 9.84 feet in diameter (3-m) and extend well into bedrock. 17 each, 6.6 feet (2-m) drilled shafts were built to support the aging river bulkhead and replace shipping bollards. In addition to shallow groundwater fed by the Detroit River, artesian conditions at depth result in a water head that is approximately 17.2-ft (5.2-m) above surface. At 95-ft (29-m) below grade Dundee Limestone, of the Detroit River Group, is moderately weathered and fracture density decreases with depth. The Dundee Limestone strength ranges from 8-ksi (55.1-MPa) to 12-ksi (82-MPa) and may carry hydrogen sulfide in fractures. Working through casing that sticks three stories out of the ground is less than ideal, but was necessary to maintain a positive fluid head and prevent artesian-related quality issues. The sheer scale of the bridge forces required a load test configuration that could impart an equivalent static load of over 38,000,000 pounds (170-MN). A suite of QA/QC tests was developed to ensure the shafts would meet the project plans and specifications to include critical base cleanliness criteria. Interesting CSL and TIP results obtained highlight the strengths and weaknesses of each test method. Cleaning drilling fluids with a centrifuge allowed recycling of product and reduced exposure to environmental contaminate exposure. Having large construction equipment working next to the river presented challenges in working pad design. A driven pile system was developed to support high oscillator forces and protect the aging seawall.

Sep 8, 2021

By I. H. Wong

The large diameter caisson foundations and their construction methods for three 50 to 60 storey high buildings in Singapore are described. The caissons are 5 m to 8 m in diameter and 40 m to 100 m deep, excavated either by hand or mechanised excavators or by drilling and blasting. Performance of the 50 storey DBS Building is described.

Jan 1, 2010

By Helen D. Robinson

The seawalls that surround Ellis Island were constructed in the early 1900s and now show varying degrees of deterioration. An innovative approach to the structural repair of the seawalls was developed, which consisted of the use of micropiles for stabilization of vertical and horizontal seawall movements. The micropiles were installed through the existing seawalls and penetrated through a thick overburden, consisting of soft alluvial deposits and relatively hard glacial till, and were bonded into Manhattan Schist. Drilling of the micropiles often encountered timber and other obstructions. The selection of micropiles for stabilization of the seawalls offered significant advantages over other foundation systems and over alternative soil improvement techniques. They allowed drilling through a variety of materials without the need for significant retooling or changes to the drilling procedure. This reduced the impact of foundation construction on the sensitive historical landscape and structures, and prevented the need for significant foundation work from the water side of the seawalls. In addition, micropiles offered relatively high installation rates and flexibility to adapt to the varying conditions along the seawalls.

Jan 1, 2008

By Vijay Kumar, Serhat Baycan, Karsten Beckhans

For the deep foundation of podium and tower of the Kuala Lumpur City Centre, BAUER (MALAYSIA) SDN. BHD. constructed 225 bored piles with diameter range of 2.0 to 2.5 m. In order to comply with the depth requirement of the design, for planning purposes and preparation for site, the drilling equipment was required to achieve a maximum drilling depth of 150 m. Actual piles constructed on site were deeper than 120 m. These dimensions caused superlative challenges which included but were not limited to; controlling the open hole stability over time with polymer, installing 70-ton heavy steel cages, pouring up to 550 m³ concrete continuously, in conjunction with installation of kingposts into workable, fresh concrete. The piling works were executed with a BG 72, the biggest drilling rig globally available, and the stringent verticality of the pile bore holes which required approval prior to cage installation. For verification of verticality, Bauer’s patented Drilling Inclination System was successfully used.

Nov 1, 2022

By Abdul Aziz Hanifah

A novel instrumentation and analysis technique, called GLOSTREXT method has recently been introduced for bored pile load tests in Malaysia. This technique provides an innovative and improved alternative for conventional bored pile instrumentation methods commonly practiced for the past few decades. Results for five case histories involving full scale static load tests for high capacity bored piles with both new and conventional instrumentation details placed in within the same instrumented piles are presented to demonstrate the advantages of this novel technique. Results show good agreement between the new and conventional instrumentation.

Jan 1, 2006

By Michael Lane

With the success of their existing casino operation on the Ohio River in Lawrenceburg, Indiana, the Indiana Gaming Co., LP planned a major expansion of the current facilities. This expansion includes a second 1400+/- car parking garage, a new surface parking lot, elevated walkways, and a new floating casino that will double their present square footage and consolidate all of the gaming activity to one floor. In March of 2006 Richard Goettle, Inc. was awarded the general contract to construct a 260? x 520? boat slip for the new Argosy VII floating casino. An Open Cell® bulkhead system was specified as the means for constructing the new slip. Our contract included the purchase and installation of 300,000 square feet of PS27.5 sheet pile, excavation of 230,000 cubic yards of soil, and a 3300 square foot Mechanically Stabilized Earth wall.

Jan 1, 2008

By J. O. Osterberg

The realities of foundation enginering are that the work never proceeds exactly as expected. The various reasons, exploration, design, construction, and legal are discussed. Case histories are presented with an analysis of why the projects did not turn out as expected and how the difficulties might have been avoided.

Jan 1, 2010

By Dennis Nottingham

Spin-fin pipe piles can develop large loads in tension, thus have evolved as a foundation product of great potential. Currently, over 500 spin-fin piles have been used successfully in dolphins, docks, buildings and bulkheads. Spin-fin piles are pipe piles with plates welded near the tip at a batter-in-screw fashion. Thus, as the pile is driven, the pile screws into position. Tests show this pile type to have highly unusual stress/strain relationships, wherein plunging failure is usually never reached either at normal or large deformations. Tension capacity can approach pile capacity in bearing; thus, large reserves are usually available for tension. Tests have been performed on 8-5/8-inch to 24-inch-diameter piles in silt, sand, and gravelly soil, to provide a broad spectrum of data.

Jan 1, 1990

By Roy Peratrovich

An innovative cost-saving design for a 1,100 ft bulkhead on the Tanana River at Nenana in central Alaska won Alaska Construction & Oil magazine's Construction Achievement Award. The designers utilized materials available nearby at low cost. They planned sheet pile enclosures, self-anchored back into shore without cell closures. They made it practical for inexperienced local workers to do the building. And they completed the project on time and below a reduced budget.

Jan 1, 1985

By Thomas Domanski

Any type of deep excavation whether for Bored Piling, Diaphragm Walls or Contiguous Bored Piling Walls depends on forming a stable borehole with a defined cross-section to receive safely the permanent materials. In modern construction the excavation depth can reach well the range of 100 m and above. The diameters of the Piles reach often sizes of 2.5 m and bigger. Top casings in Bored Piles (Diaphragm Wall none) are rather short and stability below the casing, need to be secured by stabilization slurry. The boreholes need to be formed through a variety of different materials and stand open for an extended period. Without a safe stable borehole, it is impossible to produce quality products and work cost-efficient. The understanding and proper usage of a suitable slurry is a key element essential for the delivery of Foundation Elements with high quality and within a reasonable budget. The setting of mechanical and rheological parameters in specifications is necessary and helpful, but probably insufficient to embrace and control such a key element in the practical implementation of foundation construction. The proper selection, design, implementation and supervision of slurries on site requires both from Contractors and Engineers to understand how different slurries do function. Only with this knowledge the right decisions in slurry operations can be made. This talk is directed to give some help to both, Contractor’s and Engineer’s, in understanding how different type of slurries do work. (Which ones should be preferred in what kind of soils.) The better knowledge will help the Contractor to control cost and enhance production. The Engineer will be able to assist in arriving at the appropriate technical choices and include in the specifications.

Sep 1, 2022

By Antonio Marinucci, Robin Mao

The new Hangzhou West Railway Station, which is currently in the early stages of construction, will be located in the city of Hangzhou, China. To accomplish the ambitious goals of the project, the construction work and station building was divided into three project areas. The original design utilizes 1,580 drilled shafts with diameters of either 800 mm or 1000 mm (32 or 40 inch) to support the new Station and its various ancillary structures. The drilled shafts will be tipped into the moderately weathered argillaceous siltstone a distance between 5 and 15 m (16.5 and 49 ft), resulting in an effective pile length ranging from 35 to 43 m (115 to 141 ft), respectively. For the first phase, approximately 550 production drilled shafts will be installed. Eight (8) sacrificial drilled shafts each with a diameter of 1000 mm (40 inch) were installed to a depth ranging from 50 to 57 m (164 to 187 ft), and were tested to confirm the design parameters used for the first phase, to evaluate the contractor’s installation means-and-methods, and to provide guidance whether redesign is warranted for the subsequent two phases. Bi-directional static load testing was performed using a donut-shaped Super Cell to apply unidirectional axial loads up to 13,200 kN (2,970 kip). This paper will describe the bi-directional testing and select results obtained therefrom. The axial compressive and uplift resistances determined from the testing verified that the available axial resistance of a single drilled shaft exceeded the minimum design requirements.

By Saeed Salehi Malekshah

In hybrid foundation system or piled raft foundation (PRF), the raft has adequate bearing capacity and piles are usually required to ensure overall stability of foundation and also to act as settlement reducer for high rise structures. When piles are connected to the raft, a high axial stress may develop and one alternative is to disconnect the piles from raft and consider them as stiffeners for supporting soil. This system is known as disconnected piled raft foundation (DCPRF). Cushion, a compacted coarse grained soil layer, can be used beneath the raft to redistribute and adjust the stress ratio of piles to subsoil and plays an important role in mobilizing the bearing capacity of subsoil and modifying the load transfer mechanism of piles. In this study, finite element method (FEM) has been employed to investigate the effect of different parameters such as cushion stiffness, gap height, raft thickness and piling configuration on the behavior of disconnected piled raft foundation. The analysis is performed on different foundations of hypothetical and real case histories. Results indicate that increasing the raft thickness reduces the differential settlement and pile head axial stress. Concentrating the longer disconnected piles similar to connected ones beneath the central area of raft, decreases settlement of raft. With increasing cushion stiffness, vertical stress ratio of piles to subsoil increases, but settlement decreases. Increasing gap height from 0.1 m to 1 m decreases the vertical stress ratio of piles to subsoil.

Jan 1, 2011

By Guan Jichang

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

Jan 1, 1991

By Jewels Stover, Charles A. Luxford

Oklahoma City is undergoing a replacement program for an existing 66in (1.675m) water pipeline that conveys raw water from Atoka Reservoir to the City. This pipeline currently crosses the Canadian River on elevated piers and is subject to flood hazards. To replace the existing pipeline and mitigate flood damage concerns, two parallel microtunnels will be constructed below the river channel. Access is from construction shafts located near the midpoint of the tunnels; opposing drives are launched from each shaft. This geometry dictated shafts of significant depth – exceeding 120 ft. (37m). To accommodate the casing pipe segments and microtunneling machines, a minimum shaft diameter of approximately 34 ft. (10.4m) was required. Due to the difficult geologic setting, a reinforced secant pile compression ring is specified by contract in the top 70 ft. (21.3m) of these construction shafts to provide a very low permeability support system.

Sep 8, 2021

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 Carole L. B. Mitchell

The South 180th Street Grade Separation underpass in Tukwila and Renton, Washington, USA, permits vehicular traffic to pass beneath Burlington Northern Santa Fe and Union Pacific railroad tracks. The railroad tracks were temporarily relocated onto a shoofly crossing while the permanent bridges were constructed. The maximum underpass depth is approximately 25 feet (7.6 meters [m]). The majority of the sidewalls are supported using alternating reinforced and unreinforced secant pile walls. Temporary and permanent struts brace the top of the excavation. Because the groundwater is about 15 feet (4.6 m) above the base of the excavation and the subsurface materials are loose to medium dense fill, alluvium, and soft flood plain organics, the base of the excavation was strengthened and sealed using wet cement deep soil mixing (CDSM) methods. During construction, CDSM-treated ground temporarily acted as part of the railroad shoofly shoring while the remainder of the underpass was excavated on either side of active railroad tracks. The combination of secant pile sidewalls and CDSM bottom seal allowed for easy excavation, even during wet conditions. Using a 35-foot-thick (maximum) (10.7-m) CDSM layer both to act as a bottom seal and to resist uplift pressures is a unique, dual-purpose application of CDSM technology in the United States.

Jan 1, 2004

By Ronnie Melker, Joel Webster, Daniel Belardo, Thomas Hyatt

Quality assurance of drilled shafts is highly dependent upon the construction practices used during the excavation and concrete placement process. When performed under slurry, challenges are presented in maintaining borehole stability and placing a uniform and continuous concrete column. An integral part of the construction operation is to evaluate the as-built integrity to verify the drilled shaft is capable of safely transferring the required loads to the subsurface. One such case is exemplified by a project involving the expansion of an existing public transit rail line. The expansion required the construction of a new bridge bent supported by seven 5-ft diameter drilled shafts of various lengths. The specifications for the project required both Cross-Hole Sonic Logging (CSL) and Thermal Integrity Profiling (TIP) for drilled shaft integrity evaluation. Both of these post-construction non-destructive tests (NDT) are designed to detect anomalies or the presence of regions with reduced concrete quality. However, the implementation and methodologies of performing each of these NDT methods are significantly different. Cross-Hole Sonic Logging uses ultrasonic signals emitted from a transmitter in one access tube to a receiver in another access tube. Thermal Integrity Profiling measures elevated concrete temperatures during the curing process using embedded thermal wires. Both test methods require different access details and therefore have different costs associated to the contractor or owner to perform. This paper provides a detailed comparison of these NDT methods as performed on these seven drilled shafts. The associated financial and time costs to perform each method are compared and the results are discussed in detail. INTRODUCTION Drilled shafts are a fundamental deep foundation element that can be designed to resist large bending moments as well as to transfer large compressive axial loads through weaker upper soils to competent soils or rock below. Often times when the upper soils are very soft, lateral support by casing or slurry, or a combination of both, may be used to hold back the softer soils from collapsing into the hole before concrete has been placed. Due to the blind nature of drilled shaft construction and the qualities issues that may arise during the placement process, it is essential for design engineers to specify non-destructive testing (NDT) to assess the quality of the as-built drilled shaft. CSL and TIP testing are two NDT methods designed to detect areas of lower quality concrete or soil inclusions throughout the length of the drilled shaft and determine its overall quality. Each method uses different technologies and methods to achieve the results required to determine the as-built condition of the drilled shaft.

Jan 1, 2019