Search Documents

By Stefan Larsson, Sebastian Adevik, Sadek Baker, Razvan Ignat

"Abstract Uncertain strength, deformation and flow properties in dry deep mixing columns often lead to conservative choices concerning design values where the design is regularly complemented with a surcharge fill. The surcharge not only leads to increased cost but also to logistical problems where the surcharge is a physical obstacle. The deformation properties of a ground improvement were studied by means of two small embankment load tests. The settlement measurements were also used in FEM analyses, where the effect of surcharge on creep settlements was investigated. Based on the results, the effects of the surcharge were considered negligible and could safely be ignored. The project is an example how the contractor can use a field test as an effective design approach.IntroductionGround improvement of soft soils with dry deep mixing columns, or lime-cement columns, is often combined with a surcharge fill. The main reason for using a surcharge is to force the primary settlement and some of the secondary settlement that would have occurred under the final embankment height alone, to take place under the surcharge loading. Another reason is to level out uneven settlements. Strength and deformation properties in improved soil cannot be sufficiently assessed in advance, before columns have been tested on-site, and this uncertainty often lead to conservative choices concerning design values. In order to compensate for a slow forecasted consolidation process, the design is regularly complemented with a surcharge. The surcharge not only leads to increased cost but also to logistical problems where the surcharge is a physical obstacle.Extensive research undertaken by Åhnberg (2006, 2007) shows, by means of triaxial and oedometer tests, that cementation processes and a load acting on the columns during hardening, makes the improved soil to behave as a heavily over-consolidated soil due to an increase in quasi pre-consolidation pressure. The effects of using a surcharge on the time for consolidation and creep properties are thus probably small, since the stress level does not normally exceed this quasi pre-consolidation pressure. A study presented by Venda Oliveira et al. (2013) shows that the stress level within small ranges has limited effect on the creep properties.This paper presents a case study where the deformation properties of a ground improvement using dry deep mixing columns was investigated by load tests on two small test embankments. The tests were performed at the Interchange Värtan project site, which is part of the Norra länken infrastructure project in Stockholm. The tests were not performed as a research project but simple load tests performed by the contractor with the purpose of rationalizing the design delivered by the client. One purpose of the load tests was to assess the deformations when the columns are loaded temporarily by overlaying concrete works. Another purpose was to provide some input data to a study of the effects of using surcharge on creep settlements. The analysis was conducted as finite element modeling using the commercial code PLAXIS, where creep settlements can be simulated using the built-in Soft Soil Creep model."

Jan 1, 2014

By Gordon King

The site of the First Quality Tissue plant is located on a previous paper production facility in Lock Haven, Pennsylvania. The new development, which included the construction of a tissue machine building, baled building, converting building, various storage buildings and an electrical switchgear building, required the use of deep foundation systems to transfer loads below compressible fill and alluvial soils. Loading details provided by Jacobs Engineering, the project structural engineer, detailed braced steel frame buildings with typical column loads ranging from 75 to 150 kips and slab live loads of 250 to 300 psf. As an exception to this, however, the tissue machine and stock preparation building, which had a roof height ranging up to 85 feet, had column loads ranging up to 800 kips in addition to high dynamic loads. The First Tissue plant is located in a river valley in the hills of Western Pennsylvania. To evaluate the proposed site conditions and to formulate recommendations for the structure foundations, a geotechnical study was performed by the owner. Approximately 30 borings were advanced to bedrock, with wire-line coring performed in the tissue machine building. The borings disclosed a soil profile comprising of the following:

Jan 1, 2004

By Andrew L. Peterson

CATOH Inc. of Weedsport, New York recently completed a very challenging Bored-In Pile project which features unique construction techniques in the installation and load testing of 45 and 100 ton capacity piles. The bored-in piles were installed on a twenty-nine million dollar New York State Department of Transportation project which began in the fall of 1995 and ended in March of 1997. The project included the construction of 5 new bridges to alleviate a very congested traffic network which had come to be known as the "Octopus" in the small city of Ithaca, New York. CATOH Inc. was awarded the piling contract by general contractor Santaro Industries in the fall of 1995. Piling installation work was completed in March of 1997. BACKGROUND The project is located at the southern tip of Cayuga Lake which lies in the heart of Upstate New York's Finger Lakes Region. This region is popular not only for wine making and vacationing, but also for its impressive geological history. The glacial activities that helped to form the deep valleys of this scenic area are also responsible for creating challenging underground conditions for deep foundations work. CATOH developed two pile designs to accommodate differing site conditions on the project. Internally reinforced piles were developed for use in the center of the valley and externally reinforced piles were developed for locations close to the valley wall.

Jan 1, 1997

By Sikko Doornbos

For the extension of the Paper Mill of Parenco in Renkum, the Netherlands, the application of a pile foundation was required. The demands for this pile foundation were very explicit a vibration free and soil displacing pile systems with low allowable settlement. Another important aspect was the total amount of piles (originally over 1600 auger piles) which had to be executed within 3 months, in very difficult and unhomogeneous soil. Based upon these conditions the Tubex Grout Injection Pile was chosen to be used for this project. This system involves the drilling of a steel tube with a conical pile shoe while grout is injected at the point simultaneously, creating a mixed-in-place layer around the tube. INTRODUCTION After extensive marketing, the board of directors of Parenco, decided to a large extension of the production capacity of its paper mill by building a new production building called Paper Mill 1 or PM-1. The new PM-1 extension had to be constructed beside the existing PM-2 because of limited terrain. The site is located right between the Rhine river and Renkum, approximately 15 kilometers (10 miles) west from Arnhem (see figure 1). The construction involved the building of the PM-1 extension of approximately 250 meters (820 ft.) long by 40-60 metres wide (130-200 ft.). The main structure was to be constructed of precast concrete beams and columns.

Jan 1, 1987

By Maurice Bottiau

The recent evolution of the piling market clearly shows a growing demand for screw piles with soil displacement. The recently developed Omega Screw pile ful-fill these new expectations, combining the advantages of vibration-free systems and the behaviour of a displacement pile. The paper describes recent experience and new applications with this very promissing pile. Full-scale load tests were carried out in different countries as U.K. or Sweden. A very attractive and innovative piled embankment is also described, using geogrids in order to transfer the loads from the superstructure to non-reinforced Omega-piles.

Jan 1, 1996

By Marlion T. McQuinn

This paper will discuss the design, construction, and performance of the support of excavation on the Dulles East and West Automated People Mover Tunnels and Station projects. The elements of the system included drilled soil nails and rock anchors with reinforced shotcrete to the excavated face. We will discuss the geotechnical characteristics, design and construction considerations, loading criteria, construction techniques, schedule constraints, and performance of the support of excavation system. In consideration of the conference theme, there will be a discussion of the application of the real-time instrumentation monitoring program. The project team worked to design and install approximately 710,000 square feet of shotcrete and 19,000 soil nails/rock anchors as well as excavate over 720,000 cubic yards of rock materials within 15 months and in such a manner as to minimize the disruption to airport passengers and operations.

Jan 1, 2006

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 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 Swaminathan Srinivasan, Jess A. Schroeder

"Landslide activity along U.S. 50 in Cincinnati, Ohio (USA) has caused roadway damage for decades. After a necessary closure of three lanes due to slope movements, emergency stabilization measures were undertaken to protect the roadway by providing a short-term solution necessitated by The Ohio Department of Transportation budget constraints. The landslide shear plane occurred on a sloping bedrock surface as much as 50 feet below grade. Drilled shafts were installed 40 feet downslope of the roadway shoulder and were heavily reinforced across the shear plane but steel reinforcing did not extend the full length of the shafts and was stopped well short of the ground surface. Instrumentation data has been collected for 11 years after construction has shown these “Stub Piers” have provided much more than a short-term solution and have provided an attractive alternate to conventional deep shafts or tieback drilled shaft options.INTRODUCTIONLandslide activity has occurred along U.S. Route 50 in western Cincinnati, Ohio for many decades. The site is located between North Bend and Addyston, Ohio on the right descending (cutting) bank of the Ohio River. Road distress caused by slope movements required periodic repairs over recent decades. Railroad tracks downslope of the roadway also showed signs of horizontal displacement and periodic repair. Visual evidence in 2005 suggested the shear plane extended below the US 50 roadway and extended out into the Ohio River.A weed and brush-covered slope extended down slope from the roadway at about 3H:1V for a vertical distance of about 20 feet. Above US 50, the hillside continued to rise more than 100 feet. There is a railroad right-of-way at the toe of the slope with the Ohio River bank just downslope of the railroad.In 2005, Terracon Consultants was retained by the Ohio Department of Transportation (ODOT) to perform a geotechnical study that included 17 test borings and inclinometer monitoring at 4 locations. Roadway damage was occurring (see Figure 1). After only a few weeks of monitoring, the inclinometer casings sheared off about 50 feet below grade, near the soil / bedrock interface (see Figure 2). Soon after, the roadway distress worsened, causing ODOT to close 3 of the 4 lanes to traffic and reroute traffic onto the remaining single lane and shoulder. Terracon was asked to develop a stabilization design under emergency repair conditions. However, both limited budget and time-related constraints necessitated a direction by ODOT that the solution be at least “pseudo” short-term (3 to 5 years)."

Jan 1, 2017

By Fabio Santillán, Mario Mauro, Raffaella Granata

"This paper presents the utilization of slurry walls methods for the recent remediation of three high hazard active dams in the United States. Tuttle Creek Dam, located in Manhattan, KS, required seismic retrofit. To this extent, transverse shear walls were installed on the downstream slope using self-hardening slurry (SHS) to reinforce the liquefiable foundation soils. Herbert Hoover Dike, located around Lake Okeechobee, FL, is subject to potential failure because of internal erosion, piping and slope instability at high water levels. The innovative use of the hydromill equipment with SHS allowed the successful construction of the cutoff wall through heterogeneous soils and rock. At Bolivar Dam, located in Bolivar, OH, under-seepage negatively affects the structural stability of the dam, and a partial seepage barrier wall is required through the upstream slope of the dam. In this case, the Contractor selected the plastic concrete seepage barrier, excavated by a combination of clamshell and hydromill equipment. The main features of the three projects are summarized in Table 1. IntroductionTuttle Creek Dam was constructed by the U.S. Army Corp of Engineers (USACE) on the Big Blue River in North-East Kansas in the 1950s for flood control. Tuttle Creek Dam is a zoned earthfill embankment, 7,500 ft long and about 137 ft high with a crest width of 50 ft (Fig. 1). It is located in an area of moderate seismicity associated with an old continental rift zone located just to the east of the dam. The USACE, under the Dam Safety and Assurance Program, determined the need for remediation. Site investigations and geotechnical analyses identified the upper alluvial foundation sands as being susceptible to liquefaction when subjected to the Maximum Credible Earthquake.In 2005, USACE awarded a construction-manager-at-risk/early Contractor involvement contract. The USACE and the Contractor closely cooperated to identify the most effective technologies, materials and configurations to be used in the remediation. The original remediation design required both the upstream and downstream slope stabilization of liquefiable foundation. Results of refined seismic deformation analyses revealed that the stabilization of the downstream slope and toe was needed to protect the downstream seepage control system and to provide assurance that a liquefaction-induced flow slide would not occur (Stark et al., 2012)."

Jan 1, 2016

By W. J. Grose

The Embankment Place office development over the platforms of Charing Cross Railway Station in London has presented many interesting and unusual problems to the engineers involved with the project. The main structure is supported on widely-spaced columns which penetrate the station platforms and underlying vaults, calling for high capacity foundations built in severely restricted spaces. Hand-dug underreamed piles were chosen. Whilst a conventional design approach was taken to size the piles, a detailed appraisal of ground movements was made to explore the effects of the new building loads on the existing foundations, not only beyond the site perimeter but also those amongst the new foundations. Before construction of the pile proper could take place, it was necessary to sink a caisson through the upper unstable and water-bearing soils. This being identified as a high-risk item, a full-scale trial was carried out prior to embarking on the main works. The twenty-one hand-dug piles were 2.5m diameter, over 30m deep and belled out to between 4.5m and 6.6m.

Jan 1, 1989

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 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 David S. Yang

The Cement Deep Soil Mixing (CDSM) method introduces and mixes cementitious materials with in situ soils using hollow-stem rotating shafts equipped with a cutting tool at the tip and mixing paddles above the tip. CDSM generally produces a soil-cement panel consisting of three overlapping soil-cement columns. The soil-cement panel is then extended to form walls, which are effective for excavation support and groundwater control due to the continuity and low permeability of soil-cement walls. Two design approaches could be taken in the application of CDSM for excavation support: 1) single wall design and 2) gravity wall design. The former one is treated as a wall technology and the latter one is treated as a soil stabilization method. This paper will review the CDSM equipment and installation procedures for the construction of these two types of soil-cement walls. Four case examples are used to illustrate the design and application of these two types of soil-cement walls.

Jan 1, 2003

By Roy M. Schnabel

The Fashion Island Boulevard Bridge over the Marina Lagoon in San Mateo, California is an eight span precast, prestressed concrete girder bridge. It is approximately 495 feet in length and 61 feet in width. It is supported on 36" diameter octagonal, hollow precast-prestressed concrete pile columns. The bridge was constructed in 1968 and suffered considerable damage during the Loma Prieta Earthquake in 1989. A damage survey report prepared by the State's Office of Emergency Services (OES) recorded that sixteen of the twenty-one pile-columns sustained heavy to moderate damage from the Loma Prieta Earthquake. The damage consisted of cracking and spalling at the tops of the pile-columns. Spalls at the most heavily damaged columns exposed the prestressing strands and confinement reinforcing which also showed signs of corrosion.

Jan 1, 1993

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 James Weaver

During the past 16 years, the authors have successfully used high-capacity rock anchors installed inside open-ended pipe piles, driven to bedrock, to provide uplift and overturning resistance for various structures including piers, bridges, power plant components and commercial buildings. These systems were ultimately used on the projects due to a combination of high uplift forces or overturning moments on the structures and the relatively poor subsurface conditions present at the sites. Other, foundation systems such as rock-socketed drilled shafts and spin fin piles were considered but were found to be economically prohibitive or not technically feasible.

Jan 1, 2011

By Franklin M. Grynkewicz

The subject of bearing pile performance installed by vibratory hammers has been a matter of increasing study and continued controversy. A recent case study from a major bridge replacement project is discussed which provides encouraging data on the use of vibratory pile hammers as a primary means of pile installation and also presents the problems associated with its general acceptance. The bridge project case study foundations consisted of HP 14 x 89 pile sections, designed to develop capacity primarily in friction. Preliminary tip elevations were determined by traditional static analyses. Production pile installation was performed using an IHC S-70 Hydro-Hammer. Driving criteria and final production pile tip elevations were determined after preliminary indicator pile drive tests and static load test results at bridge pier cofferdam locations. Based on impact driven production pile performance, the Contractor wished to investigate vibratory driven piles as a means to accelerate construction schedule. Dynamic pile testing procedures were used as the primary measurement tool and test results were compared to the production pile drive records and prior static load tests. Field testing consisted of driving and monitoring with the PDA impact driven piles to the design tip elevation. Three vibratory driven piles were installed to the same tip elevation and immediately subjected to impact driving and dynamic testing to compare dynamic pile resistance. The results indicated that the site soil conditions were favorable for vibratory pile hammer installation. Recommendations and procedures for proceeding with vibratory hammer pile installation were presented to the Owner. These procedures included quality control in conformance with latest AASHTO recommendations. The Owner, in spite of the site specific data base and QA/QC procedures, would not accept vibratory pile hammer installation, due to the absence of precedence. It is concluded that for vibratory methods to become accepted a rational method of analysis, design and field QA/QC procedures requires development. In addition, the engineering community and Owners/Agencies must be more open to alternate methods of foundation construction. The continued development of dynamic methods of monitoring vibratory pile installation is considered to be key to the general acceptance of this installation procedure.

Jan 1, 1991

By Michael H. Wysockey

The load test program for the pile foundation at Soldier Field included static and dynamic load tests at four locations around the site. The dynamic tests were run with no knowledge of the static results, and comparison between the two is very good. It was necessary to use a special testing hammer (not the production hammer) to demonstrate capacity with dynamic testing. Over 90% of the piles were HP14x89 with a design load of 230 tons (18 ksi). The load tests showed a capacity in excess of 590 tons for all tests where sufficient set up time was allowed. The remainder of the piles were mostly HP 12x53 with a design load of 100 tons (13 ksi). The measured capacity of these piles was typically about 250 tons. One experimental HP12×74 pile with a nominal yield of 65 ksi held 730 tons (67 ksi) before failing.

Jan 1, 2002

By James S. Graham

Foundation pile driving hammers used in New York City in the past 100 years have been drop, steam, compressed air, diesel, and hydraulic. In 1992, the first hydraulic hammer in the New York City area was purchased by Norwalk Marine Contractors, Inc. from Junttan in Finland. It was bought because of its variable energy and ease of mobilization, not because of its higher transferred energy. Heller and Johnsen engineers instrumented hydraulic hammers on nine jobs. The measured transferred energy for the nine jobs was found to average approximately 80 percent. There is no clear consensus regarding the reasons for the hydraulic hammer being more efficient in delivering energy to the pile as compared to single-acting steam/air impact hammers. To minimize pile damage during installation, and to minimize footage overruns, an up-to-date version of the wave equation software that includes an efficiency value of 0.95 for hydraulic hammers is now used.

Jan 1, 2000