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By Robert R. Morrison

Alberta Piling Contractors very rarely are required to perform major marine construction in the prairies, so it became as a big surprise to AGRA Foundations Limited to be invited by Transalta Utilities Corporation to bid on a major marine project for the Sundance Cooling Pond Expansion at Lake Wabamun, Alberta. Even more of a shock, the work had to be undertaken during Alberta's harsh winter conditions with temperatures plunging to -30 C. Not a happy situation for prairie construction workers to be in, working from barges in the middle of a lake in the dead of winter. However, it is well known that prairie boys make the best sailors.

Jan 1, 1997

By A. B. Desai

The construction of 1144 nos. of piles, each 1.5 m diameter, bored-cast-in-situ type and varying in depths from 6.5 to 23m, has been completed as foundation for 26 piers of 548 m long aqueduct across Orsang river to carry 1128 m3 water of Narmada Main Canal of the Sardar Sarovar Project in Gujarat. These piles are socketed 1.5 m into foundation grade rockmass. The portal system of 44 nos. of piles and pile cap at the top for each pier is analyzed considering the portal fixed at bottom of piles. The borings for pile shaft were done deploying reverse mud circulation rigs and also by conventional chiseling and bailing operations. Besides vertical loading tests and lateral loading test on piles, dynamic tests such as low strain integrity testing on 290 piles and high strain pile testing on 17 piles were also conducted. The results indicated that (a) the settlement/ displacement are much less than the prescribed limits (b) good quality of concrete (c) piles are firmly socketed and (d) piles have adequate structural capacity to withstand the design load.

Jan 1, 1996

By Gray Mullins

A post grouted drilled shaft foundation system was successfully used in place of the specified driven pile foundation system as a Value Engineering Cost Proposal (VECP) for the new PGA Boulevard Grade Separation Project. Pressure grouting the cohesionless sandy soils at the drilled shaft base significantly increased the end bearing capacity and stiffness allowing drilled shafts to be the more cost effective foundation system. The post grouted drilled shaft option also provided other benefits including reducing owners risk normally associated with pile driving vibrations and offered a high level of quality assurance for the drilled shafts. This paper discusses the implementation of post grouted drilled shafts from design to completion of construction. A design procedure for post grouted drilled shafts developed by the University of South Florida was used for initial VECP evaluation. Prior to construction, two instrumented test shafts were installed and load tested, one of which was post grouted. Therein, the design procedure was calibrated, tip elevations for production shafts were refined, drilled shaft construction and grouting procedures were demonstrated, and a grouting criteria was developed for the project.

Jan 1, 2003

By Emad W. Shublaq

Contractual site plans are implemented for executing pile foundations (5 x 5) at segmental concrete bridge. Project schedule demands have forced the contractor to find out the most economical procedure in achieving the goal. This paper presents a site management technique which is applied by the Contractor. This was found to be fruitful and as much as 60% saving was gained.

Jan 1, 1992

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 B. N. Hira

A multistoreyed residential complex was at the penultimate stage of construction by ONGC at Nazira, Assam. The site was situated at high earthquake zone. The subsoil was very weak and contained soft to medium clay with water table almost at the ground level. The bearing capacity of soil was quite poor particularly with predicted settlement beyond permissible limit. In this situation, the conventional shallow and deep foundations were found uneconomical and ground improvement with granular piles was considered as the viable solution. ONGC approached the Central Building Research Institute with the request to design granular piles along with R.C.C. foundation and other suitable cost effective measures. CBRI collected relevant geotechnical informations and supplimented the data by conducting field tests at site and laboratory tests at Roorkee. Rational design of 30 cm dia. and 5.00 meter deep granular piles were suggested with isolated and combined RCC footings over the reinforced soil. In addition to several structural and geotechnical advantages, the granular pile foundation provided considerable economy in the cost of construction. The paper presents the salient geotechnical and structural informations of the challenging project and provides the design details of the innovative granular pile-system. It also furnishes the design approach of the RC footings and other elements of the foundation.

Jan 1, 1996

By Jim Bruce

The Transformation AGO project, constructed between 2005 and 2008, featured a foundation trade contract that included design of pile caps and grade beams and construction of 138 permanent micropiles. The new foundation works were constructed within seven different settings ? each featuring a host of attributes challenging to constructability ? inside and outside the existing Art Gallery of Ontario, all while the gallery remained open for business. Transformation AGO resulted in several firsts for micropiles in the Toronto construction market: this was the first micropile trade contract with a multimillion dollar contract value; it featured the first static compressive load test performed beyond 7000 kN on a single micropile; the first static compressive load test beyond 8000 kN on an experimental pile cap supported by two test micropiles; and it was the first publicly funded project to go to tender with micropiles listed as the preferred foundation option. This paper outlines the successful application of micropiles at the landmark Transformation AGO project.

Jan 1, 2011

By Roy H. Borde

The design of foundations to support overhead signs is primarily based on providing adequate resistance against horizontal wind loads. The typically used subgrade reaction model for the load-deflection analysis of laterally loaded piles and shafts has been found to underpredict the capacity of shafts with length to diameter ratios less than five. The general applicability of an improved model incorporating the influence of shear and moment resistance at the shaft base is demonstrated. The detrimental effect of ground surface slope angle on the ultimate capacity is discussed, and a design chart for estimating the magnitude of the reduction in capacity is presented. A comparison between the predicted and measured responses of nine full-scale load tests performed within this study and sixteen external tests is presented. The models described are implemented in the computer program "LTBASE".

Jan 1, 1988

By D. Kolymbas

A simple formula is introduced which allows the evaluation of dynamic pile tests. The following case is considered: The pile top is dynamically loaded by an impact. The velocity v of the pile top is recorded over the time. Let v1 and v2 be the first and the second maximum of this curve. Then, the pile bearing capacity (resulting from ideally plastic resistance at the pile wall and at the tip) can be set approximately equal to Z(v1- ½ v2), where Z is the impedance of the pile cross section. Due to the assumption of ideal plastic resistances, radiation damping needs not be taken into account. Material damping may be important in rate sensitive soils (such as clay, even if it is highly overconsolidated). A simple correction procedure for material damping is proposed.

Jan 1, 1989

By experience we know about the natural event of ocean-tides. In geophysics we say that the earth-tides phenomenon is the elastico-viscous response of the earth's body to the attraction potential of moon and sun. By the fact that the tides on the planet take place in a regular periodic frequency, due to the earth rotation of 24 houres for one cycle, the rotation of the moon in about 28 days around the earth and finally to the rotation of the earth-moon combination around the sun in 365 days this phenomenon is a very important one in geophysics. The exact calculation of the acting forces is possible and the comparison of the earth's body response to these forces as well.

Jan 1, 1987

By J. Moskowitz

Construction of the new JFK International Airport Light Rail System (LRS) began in 1998 with a pre-construction load test program. This $1.2 billion design-build project consists of approximately 13 kilometers of elevated twin rail. The elevated rail system is supported on nearly 500 piers requiring deep foundations. The presence of underlying compressible and liquefiable soils as well as space constraints precluded the use of large spread footings. In the 1980's the Port Authority undertook extensive testing to evaluate various piles and drilled shafts types. The LRS piling sub-contractor and the Geotechnical Engineer conducted additional tests for this project to identify the most cost effective deep foundation type. Candidate piles types included: Monotube®, Tapertube®, and closed ended pipe piles. The tapered pile types were found to be the most cost effective and the project utilized both the Monotube® and Tapertube® piles. This paper presents the results of the load test program and the issues related to pile driving induced vibrations and ground movement.

Jan 1, 2000

By Javaid M. Alvi

This paper is an attempt to outline the emergence of Augered Cast-ln-Place piles as one of the more economical types of foundation for supporting high-rise buildings and heavily loaded structures recently constructed in the flood plains in and around the Greater Pittsburgh area. To understand the process of selecting foundation types, it is important to understand the general geology of the area and past construction activities that have taken place in the flood plains, especially along the riverbanks, during the last century. The first part of this paper presents a brief description of the general geology of the area; the second part of the paper concentrates on the historical evolution of the use of deep foundations and selected case histories; and the last part presents the results of load tests on large diameter Augered Tremie Concrete (ATC) Piles placed in sandy alluvium which suggests a much larger load-carrying capacity of these piles and also provides an insight into their future application. 2.0 GENERAL GEOLOGY 2.1 Soil Overburden Most of the high rise buildings in the Central Business District as well as along the North Shore and South Side of Pittsburgh are situated in the flood plain at the confluence of the Allegheny River and the Monongahela River where their combined flow forms the Ohio River. The flood plain consists of unconsolidated deposits of Quaternary age that overlie the bedrock of Pennsylvanian age. These deposits are called alluvium or valley fill, and include moderately to poorly sorted clay, silt, sand, gravel and some boulders. Their thickness varies from zero at the edges of the valley to about 80 feet towards the rivers (Figure 1).

Jan 1, 2001

By E. Mongilardi

The construction of large underground openings through cohesionless or weak cohesive soils and under the water table in particular, often requires a ground improvement to be done from the surface or ahead of the excavation face in tunnelling problems. To this purpose various injection procedures have been used in the past and new outstanding techniques have been developed recently, such as "jet-grouting", extending the feasibility range. The paper presents a review of basic principles and practical design criteria with particular reference to the newest trends of development. Case histories have been selected within the experience of specialist contractor Rodio Co. showing the variety of problems solved by manifold grouting procedures and layouts, in widely different soils ranging from the sandy-gravelly alluvia of Milan to the soft marine clays of Singapore.

Jan 1, 2010

By Ingemar Hermansson, Thomas Bjerendal, Mattias Grävare, Carl-John Grävare

"AbstractHigh strain dynamic pile tests (HSDPT) on driven piles have been carried out on a routine basis in Sweden for more than 30 years. The Swedish Commission on Pile research established, in the early 1980s, safety factors based on the percentage of piles tested. The safety factors could then be reduced, creating economic incentives for the contractor to carry out testing.Energy formulas adopted by our neighbour countries, Norway and Denmark, were not accepted in Sweden as a reliable method since the dynamic testing method was considered to be a more scientific and reliable method. It has become almost the only in-situ method used to verify geotechnical bearing capacity on driven piles.The typical Swedish geology of soft soils overlaying very hard strata makes it possible to verify high design loads, typically 20 kN per cm2 of pile cross sectional area for steel piles and 1,5 kN per cm2 for concrete piles.Conventionally a certain percentage of the piles have been tested in Sweden. The EC7, on the other hand states a number of piles to be tested, regardless of the total number of piles. The Swedish NA (National Annex) states a maximum distance between tested piles, which results in better distribution of the test piles over the foundation.For shaft-bearing piles in soft clays, dynamic pile tests have to be correlated by static load tests.Historical backgroundOn a research basis stress-wave measurements have been carried out for a long time in Sweden. One example is a project in the city of Gothenburg, conducted by Fellenius and Pejrud (1964). Strain gauges were glued on the reinforcement bars in 60 m long, precast concrete piles at 3 m and 25 m above the pile tip respectively. Evaluation was done with different methods such as dynamic formulas,stress-wave measurements and in addition compared with static load tests.In the 1975 Building Code in Sweden, driving criteria for concrete piles based on stress-wave theory were introduced, as summarized in Table 1. The driving criteria are intended for 3 and 4 tonne gravity hammers. For hydraulic rigs, which have free-falling hammers, the drop height indicated should be reduced to 80 % of the values in the table. The criteria were considered to include a safety factor of 3,0. For 330 - 450 kN pile load, pile with a standard a cross sectional area of 235 mm x 235 mm was used. For 600 kN load, the standard cross sectional area was 275 mm x 275 mm."

Jan 1, 2014

By Daryl W. Wurster

The Liberty Bridge in Greenville, South Carolina is a curved, cable-stayed, pedestrian bridge with primary support provided by two towers. The bridge is part of the Falls Park redevelopment. The bridge was originally designed to be supported on drilled piers. Alternately, the bridge was supported on a combination of micropiles and anchor piles because of difficult access and subsurface conditions. The use of micropiles and anchor piles led to improved construction scheduling and reduced costs. Micropiles were used to resist compressive loads. Anchor piles were used to resist tensile forces and to eliminate excessive settlement of pile caps into underlying fill during pre-stressing. This paper describes the site history, bridge construction, site and subsurface conditions encountered, and the decisions that led to support of the bridge using micropiles and anchor piles and foundation construction.

Jan 1, 2006

By Robert A. Field

Static-Load Piledriving utilizes a hydraulic push to facilitate the installation of a pile. The pile is not rotated, impacted or vibrated. A smooth pushing force advances the pile incrementally into the ground. Static-Load devices must have a reaction mass to push against. The most simple form of a Static-Load device is a jack; more advanced equipment, such as the Still Worker, also utilizes this approach. This paper focuses on the use of the Still Worker on three challenging projects. In each case, the existing site conditions made it risky, or unattractive, to utilize conventional impact, vibratory, or drilled-shaft equipment.

Jan 1, 1997

By E. Stoetzer

In all known deep mixing processes the existing soil is mixed with self hardening slurry by mixing tools that rotate about a vertical axis (augers, mixing paddles). Wall panels are constructed using sets of multiple mixing tools combined into a single unit. These techniques have been developed on the principle of the rotary drilling technology. In contrast, the new Cutter Soil Mixing or CSM technique is derived from the cutter technology. The soil is loosened and broken down by cutter wheels, then mixed in-situ by the rotating cutter wheels with the self-hardening slurry - introduced into the ground between the two wheels - to form a soil-slurry mortar. The main area of application lies in the construction of cut-off and retaining walls.

Jan 1, 2006

By David G. Winter

The first test pile for the carrier pier and south wharf at NAVSTA Puget Sound was driven on December 27, 1989, and the final pile was tested on February 26, 1990. Implementation and modification of the test pile program were done by the owners (WESTDIV and ROICC-Everett), the engineers (ABAM and Hart Crowser), and the contractor and his subcontractor (General Manson Joint Venture and GRL). The site is located as shown on Figure 1. SUMMARY OF THE SOIL CONDITIONS A soil profile along the pier is shown as Figure 2. The soil units can be generalized as follows: ? Upper Silts - Fill, sandy silt, and clayey silt extending from the mudline to an elevation of about -80 feet; ? Intermediate Sand - A medium dense to very dense silty sand unit which is about 30 feet thick near the shore, but thins and disappears offshore; ? Lower Silts - Sandy silts and clayey silts in a medium stiff to stiff condition; ? Deep Sand - A very dense overconsolidated sandy soil encountered at an elevation of about -145 feet.

Jan 1, 1990

By Darrell L. Beddard

The Loma Prieta earthquake occurred on October 17, 1989 at 5:04 PM, Pacific Daylight Time. It measured 7.1 in magnitude and was felt from Los Angeles north to the Oregon state line and east to western Nevada. The epicenter of the earthquake was located along the San Andreas Fault, in the Southern Santa Cruz Mountains just north of the City of Watsonville, California. It was the largest earthquake to occur in the San Francisco Bay area since the 1906 earthquake. A total of 87 aftershocks of Magnitude 3.0 or larger were recorded within 21 days after the seismic event. As a result of this earthquake thirteen State-owned and five locally-owned bridges were closed to traffic. Three of the most publicized State-owned structures closed to traffic were Struve Slough Bridge, San Francisco-Oakland Bay Bridge and Cypress Street Viaduct. Struve Slough Bridge was twin slab bridges that collapsed and were rebuilt and open to traffic three months after the earthquake. San Francisco-Oakland Bay Bridge experienced collapse of upper and lower spans at Pier 9 and was reopened to traffic one month after the earthquake. The Cypress Street Viaduct experienced collapse of 48 bents that resulted in the upper roadway falling onto the lower roadway.

Jan 1, 1996

By James Su

The Green River Valley in Kent, Washington, is a fast growing area containing retail facilities, warehouse factories and industrial businesses, including the Boeing Space Center. Traffic from Interstate - 5 to the West Valley Highway is highly congested. Accordingly, a new corridor, including a bridge across the Green River, was designed and constructed between 1996 and 1997. This paper presents a case history of the design elements and issues associated with the construction of the pier foundations of the bridge. Subsurface conditions were evaluated using both deep test borings and CPT soundings to evaluate the strength and consolidation properties of the supporting soils. Subsurface conditions consisted of alternating layers of loose and medium dense silty sand and sandy silt. Engineering analysis included an assessment of liquefaction as well as pier supporting capacity and associated settlement. The constructed foundations included 6-foot-diameter piers cased to a depth of 120 feet below the ground surface. The pier casings were driven to the design tip elevation and the soil inside the casing was removed by drilling. Despite performing borings and CPT soundings at specific pier locations, occasional trees, buried thousands of years ago through geologic processes, were surprisingly encountered during pier construction. This presented unique and difficult driving and drilling conditions. During drilling, the water level inside the piers was maintained near the ground surface to create a balance of hydrostatic pressure and prevent boiling of soils the bottom of the casing. After the casings were installed, the soil inside the casing was excavated, the rebar cage was installed and the pier was filled with concrete using treme techniques. Construction of the piers is complete and the completed piers have experienced negligible settlement. Owner: City of Kent Engineering Department Timothy La Porte, Project Manager Kent, Washington General Contractor: Mowat Construction Company, Kirkland, Washington Foundation Contractor: Condon - Johnson & Associates, Inc., Tukwila, Washington

Jan 1, 1998