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By Paul J. Lewis

Estimation of the axial side shear resistance of drilled shaft rock sockets is directly related to the unconfined compressive strength of the bedrock. Commonly, the mean unconfined compressive strength value is calculated from a range of laboratory test results and is used to estimate the side shear of the bedrock. This paper presents the results from a full scale axial load test performed on an 8.5-feet-diameter drilled shaft rock socket, and compares measured side shear values to estimated values for two different rock strata. Measured side shear values correlated well with the design value calculated for the ?strong? rock stratum, but did not correlate well with the design value calculated for the ?weak? rock stratum. The mean unconfined compressive strength was used to calculate the side shear in both strata, but review of the laboratory data indicates that this value may not have been appropriate for the weak stratum due to a large variation in the laboratory test results. Also included in this paper is a discussion of the subsurface conditions, the laboratory test results, and the methodology used to design the drilled shaft rock sockets for axial and lateral resistance.

Jan 1, 2013

By Nathan Iverson, Allie Brady

Located on rolling bluffs on the Zumbro River's south fork in Southeast Minnesota, Rochester is the state's third largest city and is the home and birthplace of the renowned Mayo Clinic, a nonprofit academic medical center focused on integrated health care, education and research. Mayo Clinic employs more than 4,500 physicians and scientists with another 58,000 administrative and allied health staff across three major campuses: Rochester, Minnesota; Jacksonville, Florida; and Phoenix/Scottsdale, Arizona. Originally developed as a stagecoach stop, Rochester has become a national destination for medical care, drawing more than two million visitors annually to Mayo's Minnesota location. Since January 2022, Veit & Company has been working on the construction of the Mayo 1st Ave Tunnel, which comprises three tunnels (pedestrian, utility and services), and the RMC Loading Dock projects in Rochester. These adjacent projects are on the Mayo Clinic's ever-expanding campus and represent its continued dedication to improvement and advancement as a leading medical service provider in the industry.

Jan 1, 2023

By Abid O. Adekunte

The design, construction and monitoring of the deep excavation support for the basement of a large-scale commercial development in Cavan, Ireland is presented. Excavation area was adjacent to existing structures and retained height H varied between 4.0m ? 11.0m. In areas where excavation depth H < 5.0m, wall was designed as cantilevered section. However in sections where 5.0m = H = 11m, additional wall supports were required for serviceability reasons. Traditionally, designers often provide additional wall support through the use of tie-back ground anchors, raking props and braces. On the current project, the main contractor was not in support of the use of temporary props so as to maximise working space, while owners of adjacent properties disapproved the use of tie-backs. The limited set-back between the wall line and site boundary also contributed to the complexity of the project. A rare alternative solution has been adopted. This novel approach involved buttressing the wall with steeply raking bored tension piles at regular intervals along the wall. Comparison of the monitored deflections in the cantilevered sections with those recorded at sections where tension piles were used shows the novel solution to be safe and quite effective. This approach is also considered to be more economical when compared with ground anchorage and propping.

Jan 1, 2008

By Brad W. Taylor

"During the past several months, I have introduced to civil and structural engineers an innovative solution for the integrity testing of concrete using the Thermal Integrity Profiler (TIP) Wire Cable System by Pile Dynamics. While in the process of “educating” highly-trained professionals about a technological breakthrough, I ended up being educated myself about their needs for quality control/quality assurance (QA/QC). With that in mind, I would like to focus on their two key areas of concern:• How complex is the TIP installation process?• How does the QA/QC engineereffectively analyze and report TIP test results?A few months ago, during a discussion with a senior QA engineer, he asked a question that stopped me in my tracks: “Why should we do foundation testing at all?” Turning it around, I asked, “Why wouldn’t QA/QC personnel want to know everything they could about their critical infrastructure foundation?” Honestly, I didn’t answer his question nor did I fully comprehend what he was trying to say. With his experience, the engineer understood that there has not been an integrity test or a combination of integrity tests that could deliver an inside the cage and outside the cage (cover) complete data set that would provide a definitive profile of the entire shaft. Crosshole sonic logging (CSL) becomes more effective the larger the diameter of the shaft becomes, with a maximum effectiveness between 70% and 80%, but does not provide any data of the integrity of the shaft beyond a straight line between CSL tubes. Gamma-gamma logging (GGL) provides qualitative information about the concrete surrounding the GGL tube and device, and it provides information about a small percentage of the drilled shaft concrete near its outside edge."

Jan 1, 2017

By Michael J. Garlich

Steel sheet piling has a long history of use in a variety of permanent and temporary structures. Current engineering practice uses numerous publications and standards for design guidance. U.S. design guidance is fragmented, with numerous inconsistencies between design guides. To improve current U.S. design practice, the North American Steel Sheet Piling Association has initiated a project to produce a design standard that will unify design procedures and provide specification guidance for engineers and users of steel sheet piling. The wide range of uses for sheet pile structures presents a challenge in developing such a standard. Load factors or allowable stresses acceptable for a temporary retaining wall in soil may reasonably vary from those for a river cofferdam or a dockwall located in sea water. However, it is still possible to provide consistent and rational guidance for such varying uses. The standard also can address sheet pile design aspects often neglected in U.S. publications, such as vertical load capacity and resistance to loads applied parallel to the sheeting.

Jan 1, 2008

By Dempsey S. Thieman

Innovative marine bulkhead design and construction techniques were used in the fast-track design and construction of a high-capacity, deep-water dock in the highly seismic region of Alaska?s Aleutian Islands. The geotechnical investigation and design through construction phases were completed in just eight months. The adaptable OPEN CELL® design, readily available standard flat sheet pile and an experienced contractor were integral to the successful completion of the project. The cost of the structure was determined to be approximately 50 percent of a comparable pile-supported platform dock structure, allowed higher load capacity, rapid construction, less maintenance, and provided substantially more uplands. This paper details the design and construction of this unique and challenging project. The OPEN CELL structure is a vertical flexible membrane system that offers significant advantages over other structure types: ? Its flexible membrane structure is not dependent on toe embedment for stability. ? Poor soil conditions, shallow bedrock, high seismic loads, deep water, scour, etc., can be accommodated due to its adaptable design. ? It has a very high load capacity?capable of several thousand pounds per square foot. ? Allows buried utilities which results in lower cost and reduces freezing conditions ? The sheet pile tail walls can be extended to provide increased global stability if needed. ? Standard sheet pile and connectors with traditional installation techniques allow accelerated construction schedules.

Jan 1, 2008

By Peter de Kort

Tunnels in urban areas generally require deep excavations in soils under the groundwater table. In The Netherlands uplift loads are generally taken by piles installed into dense sand layers, which are hard to penetrate. To avoid nuisance and damage to the environment, piles often need to be installed using vibration free methods, which also have the advantage of low noise levels during installation. Drilling piles and obtaining a high uplift resistance is a contradiction in itself. Franki has adopted several installation methods based on the injection of grout during drilling and/or post grouting to overcome the difficulty of hard layers. This report presents two projects, situated in Rotterdam and Sneek, where vertical tension piles in floors, subject to high uplift loads, have been used. It also explores a project in Zeebrugge (Belgium), where tension piles are installed at an inclination of 1:1 to anchor a diaphragm wall for a quay construction. Test results presented in this report show, that vibration free and soil displacing piles can be installed in very dense sand layers and that a high uplift resistance can be achieved. It is also shown, that a variety of installation methods is available, even in limited space.

Jan 1, 2008

By H. Cheng

The Bohai Oil Company has applied all together 11 jack-up oil drilling rigs (movable platforms) (1) which can be classified in terms of their forms of foundations into two types: the integ­ral mat and the column legged, as demonstrated in figure 1. Figure 1 a) indicates the entire structure of the sunk cushion type, i.e. the one with a box-like sunk cushion serving as its foundation by directly sitting on the sea bed. The length, width and height of the outer sides for the sunk cushion stand at 45.8 x 38.0 x 3.3m ( for Rig Bohai No.2 ) and 50.6 x 33.2 x 4.88m ( for Rig Bohai No.6 ), the relative areas of theirs being 1475m2 and 2008m2 respectively and both bigger than the plane areas of the rigs. With a view to realize a convenient drainage of mud while sinking, two holes of 14 x 14m and 32 x 18m in size are constructed in the center part of the sunk cushion. When work sets off, the underside of the sunk cushion operates as a foundation, the sunk cushion being connected to the platform by hull columns which transmit the load of the platform down­wards to the sunk cushion that passes it further onto the subgrade. [ ] Column legs for rigs may also be grouped into two categories considering their features: columns with and without boots. The bodies of boot columns are made up of trusses, whose bottoms, are boot-shaped with a big diameter. The diameter of boot columns of the rigs applied by the Bohai Oil Company shows bigger and it may reach 12 or 18m. In the boot columns, the transmission of the platform&apos;s weight into soil is done by the underside areas of boots. While in the case of the vertical columns, which are of cylinder columns of steel with sealed bottom ends shaped inverted arch, the entire drilling platform is supported by the carrying force delivered by the bottoms of these steel cylinders and the frictional force rendered by their outside walls. Such a type of columns is featured by a small diameter, 3m in general. Figure 2 exhibits the schematic diagram of sections regarding the two types of column legs.

Jan 1, 2010

By Dardis J. T. II, P. G. Reinhall

"Impact pile driving of steel piles in marine environments produces extremely high sound levels in the water. It has been shown that current pile driving noise attenuation techniques provide limited noise reduction because significant noise is transmitted through the sediment into the water. To solve this problem, we have developed a double walled pile to decrease the total noise transmitted into the water.The double walled pile consists of two concentric tubes connected by a special driving shoe, allowing for an air gap between the two tubes. The double walled pile is driven into the sediment using traditional equipment by striking the inner tube only. The air gap between the inner and outer tube prevents the radial deformation wave produced by the pile hammer from interacting with the water and the sediment. In one embodiment of the double pile design the inner tube can be removed and repeatedly reused.In this paper we report on the results from a recent full scale field test in Puget Sound, Washington. The use of these double walled piles reduces the peak sound pressure over 20 dB relative to single walled piles. We also show that only a 3 to 6 dB reduction is obtained when a bubble curtain is used on a single walled pile.INTRODUCTIONImpact pile driving of steel piles in marine environments produces extremely high sound levels in the water. It has been shown that current noise attenuation techniques provide limited noise reduction because the noise from pile driving is transmitted through the sediment into the water. In [1,2] we showed, using modeling and field data, that the primary source of underwater sound from an impact driven pile originates from radial expansion of the pile as the compression wave propagates down the pile after each strike. The radial expansion is coupled to the compression wave through the Poisson’s ratio of steel. As discussed in [1], the supersonic radial expansion wave (with respect to the water) produces an acoustic field in the shape of an axisymmetric cone, or Mach cone. We showed in [3] that the ability of any sound shield that surrounds the pile in the water only (such as a bubble curtain or a surrounding double wall engagement) to attenuate the sound in the water is limited by the fact that an upward moving sound Mach wave is produced in the sediment and is transmitted into the water. To improve the performance of bubble curtains and other noise shields in the water, it is necessary to attenuate the noise emanating from the sediment into the water. Figure 1 illustrates how sound from the seabed leaks out from the sediment, limiting the effect of the surrounding bubble curtain."

Jan 1, 2017

By Takefumi Takuma, Masashi Nagano, Koji Kajino

As part of the construction of a multi-span pre-stressed concrete girder bridge for Japan’s new high speed rail line, landslide preventive piles were installed on the flank of a steep slope. The rotary pressin piling method was selected to install three parallel rows of long (up to 36m, i.e., 118ft) and large diameter (1,200mm, i.e., 47.2in) pipe piles safely into the slope as a deterrent measure. They were spaced at 2.5 Dia (3.0m, i.e., 9.8ft) on center and were staggered to allow the groundwater to migrate between the piles. Each pile had a sacrificial cutting shoe welded at its toe for speedy installation and was rotated and simultaneously pressed into soil on the slope through the stable bedrock thereunder to achieve a robust landslide prevention in a relatively short period of time.

By A. Partos

It was decided to build a fourteen-storied office building over a six-storied garage and a four-storied office building. The high vertical and horizontal loads required foundations on rock approximately 18m below street level. Drilled piers (caissons) were selected. Eight caissons (1.98m diameter) were installed through the six-storied garage and four caissons from a temporary deck at the location of a former two-storied building. Excavations were done by the slurry method. Proof testing of rock was done before construction by test borings and during construction with a core barrel of small diameter. Quality control measures included telecommunications between ground crews and the equipment operator on the garage roof; records of field observations and testing of bentonite slurry and rock; and a continuous evaluation of all information. Instruments were installed in one caisson to monitor load distributions and curing of concrete.

Jan 1, 2010

By Raffaella Granta

Mosul Dam is an earth fill dam located on the Tigris River, approximately 40 km (25 mi) northwest of Mosul, Iraq. The construction of the dam was completed in 1984. It is one of the largest multipurpose dams in the Middle East, and the largest dam in Iraq. The dam provides flood control, irrigation, power generation and water supply. At 113 m (371 ft) high and 3.65 km (2.3 mi) long, the reservoir has a storage capacity of 11.1 billion m3 (392 billion ft3) of water. The main hydroelectric power station has four turbines for an installed capacity of 750 MW. The discharge system includes two bottom-outlet tunnels of 10 m (33 ft) diameter, a five-gate service spillway and an emergency fuse plug spillway.

Oct 1, 2022

By James P. Hambleton, Anastasia Nally

This work focuses on the numerical simulation of multi-plate anchor systems (e.g., helical anchors) in sand subjected to vertical loading. In assessing the stiffness and capacity of these multi-plate anchor systems, full awareness of the abilities and limitations of the various analysis methods must be understood. This work first summarizes studies completed by others and then goes on to assess the failure mechanisms of multi-plate anchors in sand and the influence of (1) plate width-to-depth ratio, (2) number of plates, and (3) relative positioning of plates. The analysis makes use of (1) conventional limit analysis, (2) so-called modified limit analysis that employs reduced strength parameters to account for the influence of soil dilatancy, and (3) the displacement-based finite element method, which considers elastic as well as plastic deformation leading to failure. The work critically reflects on limitations in the current analysis methods for helical ground anchors. INTRODUCTION Helical anchors are a relatively low cost foundation type, typically consisting of a steel rod and single or multiple plate attachments. In recent decades, they have seen rapid growth, and as outlined by Merifield and Sloan (2006) and Hambleton et al. (2014). Design techniques for helical anchors have previously been predominately empirical, as much of the past research in this field is experimentally based. It is common practice for helical anchors to be modeled as horizontally oriented plate anchors in both numerical and experimental analysis. This work focuses on analysis based on the finite element method, including so-called finite element limit analysis and the conventional displacement-based finite element method, with some comparisons made to experimental studies. Numerical simulation of anchor pull-out capacity in cohesionless soils is stunted by the many difficulties faced when using numerical analysis with cohesionless soils. Additional variations can be seen when comparing the serviceability based load capacities to the ultimate load. In this work, both the force-displacement response (stiffness) and the ultimate anchor capacity are assessed, with more focus on the latter. This work focuses only on analysis techniques for multi-plate anchors with vertical loading in cohesionless soils. Many studies have been completed in this area, some of which assume a rectangular plate in a plain strain model (Rowe & Davis, 1982; Merifield & Sloan, 2006; Cerfontaine et al., 2019). Whereas others use axisymmetric conditions (Baker and Kondner, 1966; Saeedy, 1987; Murray & Geddes, 1987; Ghaly & Hanna, 1994; Sakai & Tanaka, 1998; Merifield et al., 2006;) and minimal studies considered both axisymmetric and plane strain in the one study (Vesic, 1971; Tagaya et al., 1988; Murray & Geddes, 1987; Sarac, 1989).

Jan 1, 2019

By Scott M. Mackiewicz

This project includes replacement of the historic vertical-lift span Meridian Bridge (U.S. Highway 81 over the Missouri River) that connects Yankton, South Dakota with rural Cedar County, Nebraska. The new 76-foot wide, 1,590-foot long steel plate girder structure required the use of drilled shaft foundations that extended into the underlying Carlile Shale formation. Designers indicated that an individual drilled shaft capacity of about 2,000 kips will be needed at each of the river piers, and based on the subsurface information, 8 to 10-foot diameter drilled shafts extending to about 115-foot would be required for support of the bridge structure. An Osterberg Load Test was performed on one test shaft to determine the ultimate skin friction and end bearing of the Carlile Shale. This paper describes the design and installation of the load test drilled shaft as well as presents the load test results as compared with predicted design values determined using FHWA methods.

Jan 1, 2008

By Gerry Houlahan

"The 2015 Outstanding Project Award (OPA), which recognizes the superior work of DFI members, was awarded for the San Francisco- Oakland Bay Bridge New East Span. The award was presented to representatives from Caltrans and the T.Y. Lin International/Moffatt & Nichol Joint Venture at the DFI 40th Annual Conference on Deep Foundations in Oakland, Calif. A committee selected this project based on size, scope and challenges of the project; degree of innovation and ingenuity exercised; and the uniqueness of the solution to the difficulties of the job. A bridge across the bay between San Francisco and Oakland was proposed as early as 1872, but it took until November 12, 1936, until it became a reality. The bridge spans to the west of Yerba Buena Island were conventional suspension spans, while the east spans used a steel cantilever truss design and simple steel truss spans. This double-deck bridge served the Bay Area well until 1989. In that year, the magnitude 7.1 Loma Prieta earthquake damaged the East Span of the San Francisco-Oakland Bay Bridge. The resulting interruption to service across the bay demonstrated the vital role this bridge plays in the economic and life safety activities of the Bay Area. The project owner, California Department of Transportation (Caltrans), determined that the safest, most cost-effective solution was a total bridge replacement. The Engineer-of-Record, T.Y. Lin International/ Moffatt & Nichol Joint Venture, working closely with Caltrans, the Metropolitan Transportation Commission (MTC) and the California Transportation Commission (CTC), was charged with developing a comprehensive design strategy that met the project’s stringent criteria for seismic safety. These criteria included the new bridge’s designation as a regional Lifeline Structure that must open to emergency traffic shortly after the occurrence of a 1,500-year return period earthquake"

Jan 1, 2015

By Avi Shonberg

With the advancement of offshore wind farm projects towards deeper waters and larger wind turbine generators, founda- tion solutions other than the monopile have received increasing attention over the past 5 years. Monopiles are the most commonly used foundation solution for offshore wind turbines, with 82% in European waters founded on monopile foundations (EWEA, 2019). However, 2018 saw a record number of suction bucket jacket (SBJ) structures, which consist of a three-legged jacket sup- ported by a suction bucket at each leg (Figure 1), installed for offshore wind. applications. SBJs have now been installed successfully at the Borkum Riffgrund 1, Borkum Riffgrund 2 and Aberdeen Bay offshore windfarms. Suction-installed foundations, referred to in this paper as suction buckets, suction caissons, suction piles or suction anchors, have been widely used in the offshore industry since the early 1980s for a range of offshore applications predominantly as anchors for floating offshore structures - where they are "the most widely used anchor types for deep-water mooring applications" (McCarron, 2011). Suction buckets, installed using pumps that generate suction forces by creating a pressure difference between the inside and outside of the bucket, allow for the installation to be undertaken with minimal noise and without the use of mechanical force. Therefore, a key difference between suction-installed foundations and other foundation types is that the installation design, which must consider the soil type, soil strength and installation specific risks (for example, soil stratification with significant differences in permeability) may have a direct influence on the dimensions of the foundation. While the number of SBJS installed for offshore wind applications has increased significantly in recent years, the installation process for SBJ struc- tures is yet to become standard practice and is considerably more complicated than the installation process for mon- opiles. This paper provides a brief

Jul 1, 2022

By Mauricio Coto

Three bidirectional static load tests (BDSLT) were executed on bored concrete piles, as part of the permanent foundations for two buildings sites located at the Sabana, San Jose, Costa Rica, separated at a relatively short distance of about 1 km. Unit skin friction values obtained for both sites, principally for the “Lahar” layer show that in general, friction pile capacity from the tests is higher than anticipated per static calculations from soil borings geotechnical parameters correlations. Results from the tests were also compared with dynamic load tests (DLT) executed at other two sites in the surrounding area, and with a Finite Element (FE) Analysis that model soil-pile interaction for one of the projects. On the other side, some construction issues were detected on one of the sites, which negatively affected the end bearing capacity, but being that pile friction was higher than anticipated, the required overall pile capacity was accomplished. The BDSLTs results of these tests help to better understand the geotechnical behavior of the soil layers in the Sabana. Moreover, they also show that is possible to optimize the design and construction of other bored pile supported buildings and structures on the zone.

By Jeffrey A. Gebhard

As part of the design and construction of the new St. Anthony Falls I-35W Bridge, a full-scale load test was conducted on a 6 1/2-foot diameter drilled shaft in the St. Peter Sandstone. This load test helped identify shaft-rock interaction properties, including end bearing and multiple zones of differing shaft resistance for design of the drilled shafts beneath the three piers adjacent the river. The load test was designed by Load Test, Inc., Braun Intertec and the design team of Figg Bridge Engineers/TKDA and constructed by Design Build Consortium of Flatiron/Manson. Oversight was provided by the Minnesota Department of Transportation. Based on these test results, the drilled shafts supporting the St. Anthony Falls I-35W Bridge were designed to reduce risk and maximize economy for the people of the State of Minnesota.

Jan 1, 2009

By Ray Zelinski

Caltrans sponsored a research project in 1992 which incorporated proprietary and generic pile types. The piles were subjected to axial tensile/compressive loads in deep, soft soils. Descriptions of various pile types and systems, scenarios leading to the proposal to test the systems, and load test results were/will be provided by other presenters at this seminar. Therefore, this paper will focus on the issues surrounding use of test results and proprietary pile systems on Caltrans construction projects. The primary issues facing Caltrans during implementation are as follows: 1) producing pile cap designs for a range of pile types and loads; 2) providing construction specifications which allow fair competition among the system vendors, yet assure design and ultimate capacities; 3) Develop quality control standards for pile system materials and installation techniques which guarantee pile durability for static and dynamic loads; and 4) assure that foundations have adequate lateral capacity.

Jan 1, 1993

By N. V. Nayak

Konkan Railway Project is one of the most ambitious railway construction projects in India, involving construction of a 760.km long, Broad Gauge (1676 mm), single track railway line, connecting Roha in Maharashtra State with Mangalore in Kamataka State. The railway line travels along the Western Coast of Indian subcontinent, through states of Maharashtra (382 km), Goa (105 km) and Karnataka (273 km) (Fig.1). The project alignment traverses through one of the most formidable terrains ever encountered, in the history of railway construction in India. In the State of Goa only, railway alignment is crossing 6 major rivers Terekhol, Chapora, Mandovi, Zuari, Sal and Talpona. Zuari Railway Bridge (1305.6 m), Mandovi Railway Bridges (I and II) (1182.7 m) rank as 2nd and 3rd long bridges, (first longest bridge being Sharavati Bridge (2.2 km} at Honavar) which have been constructed on Konkan Railway. All these three bridges have been constructed by M/s.Asia Foundations and Constructions Ltd. (AFCONS). This paper presents, case history of construction of pile/caisson foundations for Zuari and Mandovi Bridges.

Jan 1, 1996