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By Thomas W. Scott, Manh N. Tran

Marine environments present a range of challenges for pile construction. This paper contains a discussion on the design and construction of marine piles for a recent Toll Shipping wharf upgrade in Burnie, Tasmania. The project involved several new structures including mooring, berthing and ramp dolphins supported by driven tubular piles with rock sockets, and an onshore mooring dolphin and ramp abutment supported by bored piles. Through the project, a range of construction challenges were experienced, including availability of tubular piles, the different penetration depths of driven piles into rock, the ability to drill out sockets when the piles were raked, the difficulty in verifying the design intent, latent conditions and ship impacts. The paper will present a summary of the different factors that influenced design concepts for the structures involved in the upgrade, and the challenges involved in the design of the structures. Following this, the paper will describe the methodology used to verify the design (including a pullout test), observations made during pile construction and lessons learned on how to limit risk throughout construction.

Nov 1, 2022

By Scott A. Walker, Gabriel J. Alcantar, Brian Zuckerman, Ramin Golesorkhi

"The stadium development consists of construction of a 68,500-seat, open-air NFL football stadium for the San Francisco 49ers. The main structure will consist of a 7-story above grade steel structure supported by over 3,000 piles. Berkel and Company Contractors, Inc. (Berkel) was selected as the design-build pile contractor who used their auger pressure grouted displacement (APGD) piles for this project. During an indicator pile installation and pile load test program, fifteen piles were tested to develop installation criteria to support demands of 150kips tension and 180 kips compression. Following the indicator pile program Berkel installed 3088 piles in 30 working days. Throughout pile installation data were collected with an automated data acquisition system (DAS). During pile installation field engineers from Treadwell & Rollo observed the pile installation as well as the real-time data from the DAS. Strategic staging and pre-production planning by Berkel along with consistent collaboration with the design team created an atmosphere for a successful and on schedule project completion.IntroductionThe new San Francisco 49ers Stadium in Santa Clara, California will be a 68,500-seat facility, a rendering of which is shown in Figure 1. The main structure will consist of a 7-story above grade steel structure supported by more than 3,000 piles. The north, east and south portions of the stadium are designed as an open seating bowl, while the western portion includes open seating at the lower levels and seven-story tower which houses over 150 suites.The stadium project includes the stadium structure, as well as elevated open pedestrian walkways, commercial community space, and three new pedestrian bridges spanning a nearby by creek. Sustainable designs and innovations such as a green roof, photovoltaic panels, a ground source geothermal system, stadium-wide Wi-Fi capability, and access to public transit are provided throughout the project. The stadium is designed as an open, light, and airy structure and is surrounded by an existing amusement park, office buildings, the Santa Clara Convention Center, and the training facility of the 49ers."

Jan 1, 2015

By Aaron L. Sacks, David R. Good, Srinivas Yennamanda, Joseph K. Carey

Construction of Parcels 6 and 7, the second phase of The Wharf, began in 2019 and geotechnical construction was completed by December 2020. The overall project consisted of horizontal site, parks, and office buildings. The Wharf’s Phase 2 development includes approximately 1.2 million ft2 (110,000 m2) of above-grade construction including five multi-story, mixed-use buildings constructed over up to three levels of underground parking. The site is located between the WMATA Green Line Tunnels to the north and the Washington Channel to the south; it is bisected by a 108-in. (2740-mm) diameter DC Water outfall pipe. This arrangement, along with very difficult ground conditions, created challenges in the geotechnical design and construction. The support of excavation for this complex project required several different methodologies, including sheet piles, soldier piles, displacement piles, tiebacks, deep foundation anchors, jet grouting, and internal bracing with multi-tier rakers. Ground improvement was also required for support of spread footings in soft soils over the garage footprint. Underpinning of the active 108-in. (2740-mm) diameter DC Water outfall pipe running on a north/south alignment through the center of the site between the two garage structures was also performed. Since portions of the support of excavation are below the groundwater table, an extensive pre-excavation dewatering program was necessary and was separate from the foundation package. On the north side of the project, support of excavation (SOE) was required on a curved alignment, offset approximately 10 ft (3 m) from the outbound Green Line tunnel. Due to the proximity of the tunnel, a stiff, near-zero displacement wall was required. A portion of the buildings extend over the tunnels, imparting load to the tunnels to approximately restore original overburden loads excavated for the basement space. The building foundation is a 3 to 4-ft (0.9 to 1.2-m) thick mat slab anchored into the Potomac clay formation. Continuous movement monitoring of the tunnels was performed by an automated system. This paper describes the design and construction of the SOE and foundations for this high-profile project, which required collaboration between the Owner, Engineer, Construction Manager, and Specialty Geotechnical Contractor to solve many challenges.

Oct 1, 2022

By José Carlos A. Cintra

This paper addresses a new experimental procedure to measure the shaft friction and the base resistance of bored piles during static load tests. It is proposed that a set of polystyrene foam discs, placed between the shaft and the base of the pile, be used instead of the usual instrumentation. Throughout the initial stages of the loading test, the foam discs will allow only the mobilization of the shaft friction. The load x settlement curve clearly shows that the shaft friction vanishes at low settlement values. As the load test proceeds, the base resistance is also mobilized. This procedure was used in two belled piles bored at the Experimental Foundation Field of the University of São Paulo, at São Carlos, Brazil. Both piles were 8 m long and had a shaft diameter of 0.6 m. The enlarged base had a diameter of 1.5 m and a height of 0.9 m. Twenty foam discs with a thickness of 20 mm each were placed between the enlarged base and the shaft of the pile. The load tests indicated ultimate shaft frictions of 28 and 30 kPa for measured settlements of 8.98 and 7.39 mm. Base resistance values at failure were 617 and 499 kPa, for a chosen settlement of 10% of the pile base diameter. The proposed approach seems to be straightforward, efficient and inexpensive.

Jan 1, 2002

By Pawan L. Sethi

Design and construction of deep foundations and basements is increasingly becoming more complex, as the density and frequency of urban development increases. This growth brings various associated challenges in the form of design considerations and construction challenges. This paper discusses some of the challenges routinely encountered as well as some specific complications in this area, based on author’s experience gained through exposure as specialist contractor (designer), consultant and specialist consultant, along with some information on how these challenges were overcome. The paper highlights some of the key aspects of design coordination and importance of having an awareness of the overall perspective. Examples will be used to illustrate practical problems and the approaches used to respond.

Nov 1, 2022

By S. P. Mukherjee, Smita Tung

"Piles are generally subjected to uplift in case of under ground and water front structures. Sometimes piles are also to resist uplift loads in transmission towers, dry rock, and so on. Experimental investigations of single piles and pile groups have been carried out using model hollow circular aluminum piles, having 25.4 mm outer diameter and lengths of 600 mm, 750 mm and 900 mm. Pile groups of 2?1 and 2?2 arrangements have been used in the experimental investigations. L/d ratio has been kept equal to 24, 30 and 36 in all the cases. All the single piles and pile groups have been tested under vertical uplift. Spacing between two piles in a group has been varied with respect to pile diameter such that spacing to diameter ratios of pile are 3, 4 and 5 in case of pile groups. An attempt has also been made to analyze those models of single piles and pile groups under vertical uplift by PLAXIS 3D software. Good analogy has been observed between the results of experimental and numerical studies. A parametric study has been carried out to observe the variation of ultimate uplift capacity of pile groups with spacing and depth of embedment. It is observed that for a particular embedment length of pile and a particular group arrangement the ultimate uplift capacity increases with increase of spacing. It is also investigated that for a particular spacing and particular group arrangement, the ultimate uplift capacity increases with increase of embedment depth. Those variations have also been presented with graphs which are generated considering non dimensional forms of parameters. The paper brings out change in pullout capacity of pile groups with spacing and embedment depth of piles.1. INTRODUCTIONPrediction of uplift capacity of single piles and especially of pile groups is one of the most interesting areas of research in geotechnical engineering. Pile foundations are frequently used to transmit the superstructure loads to deeper strata if the subsurface soil is of inadequate strength. The worst possible case may be considered to occur when all the piles in a group subjected to uplift. In cohesionless soils, the shaft resistance is an important source of pile capacity under axial loading, especially when the pile is subjected to uplift loading. Poulos and Davis (1980) recommended estimating the uplift capacity of piles as 2/3 of the downward shaft resistance. Later Ramasamy et al. (2004) indicated that the upward shaft resistance is significantly less than the downward shaft resistance. Some studies were conducted on the behavior of a single pile under uplift loads, such as those by Sowa (1970), Vesic (1970), Das and Seeley (1976), Levacher and Sieffert (1984), Rao and Venkatesh (1985), Chattopadhyay and Pise (1986), and Shanker et al. (2007). Das et al. (1976) conducted a model study to test the uplift capacity of single piles and pile groups buried in sand, and they also determined a relationship between the efficiency of a pile group and its spacing. Chattopadhyay and Pise (1986) proposed an analytical method for predicting the uplift capacity of piles embedded in sand and obtained reasonable agreement between experimental and theoretical results. Gaaver (2013) investigated experimentally that an upward displacement of about 1.4–2.5% of the pile diameter is required to attain the net uplift capacity for both single piles and pile groups. The uplift resistance of pile groups depends on the several variables like group size, shape, spacing to diameter ratio of piles, embedment depth to diameter ratio of piles, soil type and its density and soil-pile friction angle."

Jan 1, 2015

By Joseph A. Sopko

The first documented procedures for designing frozen earth structures are over 50 years old, implemented long before the introduction of the Finite Element Method (FEM). Since that time, the development of three-dimensional models has made the traditional and often over-conservative methods relatively obsolete. This paper discusses a new approach that is largely dependent on the analysis of internal stresses with the frozen structure and comparison to frozen soil laboratory tests. A specific design process is discussed related to initial field investigation, laboratory testing, structural and thermal analysis, and performance monitoring. The design results are compared to case histories in the field that verify the procedure. BACKGROUND One of the first documented methods to designing frozen earth retaining structures was by Sangar (1968). Methodical refinements were published by (Harris 1995) and published by the International Symposium on Ground Freezing in 2002 (Andersland et al. 1991). The structural design or thickness of the frozen mass was based on the unconfined compressive strength of the frozen soils. Two simple equations for determining the thickness of a frozen shaft are shown in Fig. 1 and the first two equations below.

Jan 1, 2019

By Babak Mamaqani, Pirooz Barar

The Heights project was located at Fashion Valley North, San Diego, CA. The scope of the project was to replace two existing commercial buildings with a large 7-story multi-family residential building. There was an existing 1:1 slope on the north side of the site. A permanent soil nail wall, 1,000 linear ft long, with a maximum height of 100 ft, was needed to replace the 1:1 slope at the north side of the project to accommodate the development. Previously there was a design for the permanent soil nail wall which required up to 115 ft long soil nails with large diameter rebars and 13 in. thick permanent facing. PB&A was engaged by the owner to conduct soil nail design optimization and value engineering to reduce construction costs and improve scheduling. First, the SnailPlus program was used to check the stability under static and seismic conditions and to design soil nail lengths and sizes. Then, soil nail head forces were calculated to design the permanent facing using FHWA recommended procedure. Another challenge of the project was to evaluate the interaction between a future San Diego Gas and Electric (SDG&E) tower and the soil nail wall. Finite element analyses were conducted with the PLAXIS program to ensure the deflection of the future tower would be within the acceptable range. The soil nail design optimization helped the owner to save approximately $800,000 in construction cost and improved construction scheduling.

Sep 8, 2021

By Julie H. N. Hampden, Per G. Reinhall

"Executive summary: Impact pile driving of steel piles is a common construction practice in freshwater and marine environments for the building of structures and foundations. This practice produces extremely high sound levels underwater that have proven injurious to aquatic fish and wildlife. To limit impacts to sensitive species, resource management agencies employ a variety of different strategies including timing restrictions to limit in-water construction windows to those months when there are low flow conditions in lakes or rivers, to those hours when tides are low, or to periods of the year when species of concern are least likely to be present in the project vicinity. In addition, permitting agencies have identified noise thresholds above which sensitive species could be injured, resulting in additional project conditions to curtail the extent of project noise impacts including: limiting the number of piles or pile strikes per day, requiring biological monitoring, and mandating the use of noise attenuation techniques, such as bubble curtains and cofferdams. Numerous studies have shown current noise attenuation techniques are costly and provide limited or variable noise reduction [1-3]. This is because the noise from pile driving is not only transmitted through the water column, it is also transmitted through the sediment back into the water column [1, 4-8]. Though these protective measures may help to reduce project impacts, they also result in additional complexity, expense, and potential risk for project delivery. Marine Construction Technologies, a Public Benefit Corporation, in collaboration with University of Washington and Washington State Department of Transportation, has developed a pile that can be installed with standard pile driving technologies (vibratory or impact hammers) and consistently decreases the total noise transmitted into the water. The double-walled pile is relatively quiet in comparison to unattenuated piles or existing noise attenuation techniques. This technology not only reduces the risk to sensitive species by minimizing the extent of potential impacts, it also reduces potential risks to project delivery by limiting the size of monitoring areas, minimizing the need to cap daily production rates, and eliminating the need for deployment of additional noise attenuation devices. Results from finite element modeling of the pile, scaled prototype testing, and full scale field testing in Commencement Bay (October 2014) and Vashon Island (October 2015) in Puget Sound, Washington indicate a reduction the peak sound pressure between 14 and 20 dB relative to single walled piles at a range of approximately 10 meters. These tests also confirm that the double-walled piles provide drivability similar to standard steel piles. In addition, preliminary calculations for capacity and structural characteristics demonstrate that double-walled piles provide equivalent or better performance than same-sized standard piles."

Jan 1, 2017

By Sung-Ryul Kim, Woong-Jong Park, Juhyung Lee, Si-Hoon Lee

"A bucket foundation has been considered to be a potential foundation technology for offshore wind turbines. In this study, a series of 1-g model tests were performed to analyze the accumulated rotation of suction bucket foundations under long-term cyclic horizontal loads. The model suction buckets were made to have the embedment ratios of 0.5 and 1. The dry model ground was prepared to have two different soil densities by air-pluviation method. A horizontal cyclic load over 104 cycles was applied varying the loading amplitude. Test results showed that the accumulated rotation of the bucket foundation increased with the increase in the number of cycles and load magnitudes. Based on the model test results, a new equation was proposed to evaluate the accumulated rotation of the bucket foundations in sandy ground under long-term cyclic horizontal loads.INTRODUCTIONRecently, a bucket foundation has been considered to be a potential foundation technology for offshore wind turbines. In terms of economy, a bucket foundation has been considered to be an economical foundation type at sea beds where ground condition is clay or medium dense sand.A bucket foundation resembling a bucket is a kind of suction-installed foundation units. It is a skirted steel foundation which is open at the lower end and closed at the upper end by a lid. The embedment depth ratio (L/D) of a bucket foundation is usually less than one. Figure 1 shows an example of a bucket foundation. Offshore wind turbines are subjected to long-term cyclic loading by wind or currents. A bucket foundation is installed in soil grounds, so the long-term cyclic loading may induce the accumulation of soil deformation.In this study, the accumulated rotations of the bucket foundations in sandy ground were investigated under long term cyclic horizontal load. The number of cycles up to 104 cycles was applied varying load magnitude. The accumulated rotations of the bucket foundations in sandy ground were analyzed based on the test results."

Jan 1, 2016

By Darren S. Diehm

"Construction for the restoration and expansion of 102-year-old Wrigley Field in Chicago, Illinois began at the conclusion of the 2014 baseball season. This six year project involves structural upgrades to the Stadium, improvements to the facade, infrastructure, restrooms, concourses, suites, press box, and bullpens, as well as the addition of restaurants, patio areas, batting tunnels, video boards, an adjacent Office-retail Tower and a new Hotel. The Bleachers were demolished and replaced, and a new underground Clubhouse was constructed for the Chicago Cubs beneath a new open-air Plaza. The 1060 Project is privately funded, projected at $750 million (US). The work will be completed in phases during consecutive off-seasons, each with a maximum 23-week duration extending through the Chicago winter. Ownership mandated that on-going construction cause no disruption to the Major League Baseball season, have no impact on hosting concerts and other special events, and it should not adversely affect seating capacity, or diminish the fan experience.The 1060 ProjectAfter purchasing the Chicago Cubs baseball team in 2009 from the Tribune Company, the Ricketts family began planning the renovation and improvement of Wrigley Field and its near neighborhood surroundings in Chicago, Illinois. What came to be known as the 1060 Project was officially announced at the annual Cubs Convention in 2013. Construction began on the $750M privately funded project in October 2014 at the conclusion of the Major League Baseball season. In their vision, the Ricketts committed the 1060 Project to three primary goals. First and foremost as a MLB franchise, the work should provide a meaningful contribution toward winning the World Series and ending the championship drought which stretched to the last win in 1908. Second, the project should be focused on preserving and improving Wrigley Field. Finally, the project should be committed to outcomes that enable the team to be a good neighbor and provide economic and social benefit to the local community.Constructed as Weeghman Park in 1914 for an estimated total cost of $250,000, the stadium provided seating for 18,000 fans and a home for the Chi-Feds and Whales of the National Federal League. The Chicago Cubs were enticed to move from the West Side Grounds in 1915. In the next 100 years, the Wrigley Field would be sliced apart and expanded, double its seating capacity with the addition of double deck grandstands, be enclosed by bleachers (and an ivy covered wall), and, in 1988, experience its first nighttime baseball game with the addition of lighting.The 1060 Project has a total budget of $750M, with an expected construction value of $350M. It is projected to add over 2,100 jobs to the economy and be completed before the 2020 baseball season. The work will be completed in phases during consecutive off-seasons, each with a maximum 23-week duration extending through the Chicago winter. Ownership mandated that on-going construction cause no disruption to the Major League Baseball season, have no impact on hosting concerts and other special events, and it should not adversely affect seating capacity, or diminish the fan experience."

Jan 1, 1900

By Krishnendu Mandal

"For a multi-story building project in Kolkata, a pile load testing program was conducted to minimize pile performance uncertainty resulting from variable subsurface conditions and to verify the pile load vs. settlement response. The program consisted of performing five (5) instrumented load tests on augured cast-in-place (ACIP) pre-production test piles. Vibrating-wire strain gages and extensometers were installed in the test piles at strategic locations to enable measurements of the load vs. deformation behavior of the test piles. This paper presents a description of site subsurface conditions, test pile installation, instrumentation setup for a maintained load test (MLT), static compression pile load test results, and pile instrumentation result interpretation. Average mobilized unit shaft resistance values are calculated.2.0 INTRODUCTIONThe project site is located in Kolkata, near river Ganges, and the proposed development plans consist of constructing six (6)25-story (G+25) towers; see Fig. 1 and Fig. 2 below for approximate site location and proposed development layout, respectively. The buildings were designed to be supported on ACIP piles. A field load test program was implemented to verify sub-surface conditions and pile design. The test program consisted of installing Five (5) instrumented test piles numbered LP1A and B through LP6A and B, and performing static compression load tests on these piles. The piles were instrumented with vibrating-wire strain gauges and extensometers, so that the pile shaft resistance distribution along pile length and the pile toe resistance could be interpreted using direct instrumentation measurements."

Jan 1, 2015

By Remco Offenberg, Marcel Bielefeld, Martijn van Delft

The question of the continued suitability of existing foundations arises when the function of the superstructure changes. This can occur when the superstructure is replaced or when the existing structure is expanded, leading to higher loads on the existing foundation. Quite often it is a challenge to define the suitability (with respect to integrity, bearing capacity or both). The lack of information on the existing foundation (such as pile dimensions, installation records, original soil investigation, design calculations, etc.) makes it frequently seemingly impossible to assess whether the foundation or foundation elements can be re-used. The paper outlines the tools available to an engineer to evaluate existing foundation piles for potential re-use. The paper illustrates the application of these tools through a few case studies from The Netherlands, including the evaluation of a 400 years old bridge foundation to address increasing traffic loads.

May 1, 2022

"The Metropolitan St. Louis Sewer District (MSD) in Missouri, the country’s fourth largest sewer system, is upgrading its storm and wastewater infrastructure in a 23-yearlong, $4.7 billion initiative called “Project Clear.” Historically, during times of intense precipitation, the current sewer system becomes overwhelmed. The primary goals of this project are to improve water quality and to alleviate many wastewater concerns in the St. Louis region by planning, designing and building community rainscaping, system improvements and an ambitious program of maintenance and repair.Part of the system renovation has focused on constructing underground tunnels for storm water storage, permitting controlled drainage of runoff, and preventing overflows into rivers and streams. Construction plans for these storage tunnels called for eight vertical intake and ventilation shafts to be bored from the ground surface. These shafts will then be intercepted in the bedrock at a depth of about 150 ft (45.7 m) during the excavation of the 3,000 ft (915 m) long underground tunnel that will be about 28 ft (8.5 m) in diameter. According to John Deeken , a geotechnical engineer with Black & Veatch Corp. and construction manager for the Maline Creek project, the drilling and blasting technique for creating the shafts was ruled out because the project was located in a residential neighborhood. “We could have used rock coring or a cutter head, but the drop shaft for this project is constructed within 10 ft (3.05 m) of an existing 108 in (274 cm) diameter sewer main,” Deeken said. “We had to take precautions to avoid damage to it.”A primary planning mandate of all MSD Project Clear phases requires minimized impact on traffic and residents. The canister drilling method enabled work to be confined to the median of a residential boulevard running perpendicular to the side street without detouring traffic. In addition, canister drilling offered a highly-precise means to create the shafts, leaving a smooth-sided borehole, right on target. Ground conditions in this 132 in (3.35 m) diameter intake shaft were wet due to the high groundwater levels and close proximity to the Mississippi River. “They’ve been finding shale in 2 to 6 ft (0.6 to 1.8 m) layers between weathered layers of Mississippian limestone,” said Dan Spiecher, technician at Center Rock (CRI). “The 2 ft (0.6 m) layers we can punch through. The 6 ft (1.8 m) layers slow us down.”"

Jan 1, 2017

By Nasr Sheta

"After Hurricane Sandy, the stability of an earth slope in the Atlantic Highlands, New Jersey in the United States was deteriorating due to slumping soils and erosion from flooding. A slope stability evaluation indicated the slope did not satisfy the requirements of the local building code. A triple-tier, pile-supported and mechanically stabilized earth wall was designed and constructed to stabilize the slope. The construction was planned from a 3-m-wide roadway and, because of rough terrain and limited work space at the site, a cast-in-place drilled-pile construction was deemed impractical due to slow pile production. An alternative procedure was utilized by pre-drilling holes, and installing precast tip-and-shaft-grouted (PCTSG) piles, which extended to competent soils to improve slope stability. A grade beam, connecting the PCTSG piles along with soldier beams and concrete lagging were used to form the lowest tier of the slope stabilization, while the middle and higher tiers were built as mechanically stabilized earth. The stability of the proposed stabilization was analyzed using 2-D non-linear finite elements. After construction, monitoring of the wall continued for about 8 months to check its performance, and indicated lateral and vertical wall movements were less than 25 mm and 6 mm, respectively, indicating effective slope stabilization.INTRODUCTIONStabilizing earth slopes using piles to connect near-surface unstable soils to underlying stable ground masses has been investigated by many researchers, who presented various approaches to evaluate the contribution of the pile system towards improving the stability of the slope. Some of these approaches consider the piles as structural elements receiving forces from the upper sliding ground mass and transmitting these forces to the underlying stable one. The force from the top sliding mass is applied at between one third and one half of the pile embedment into the top sliding mass, Anagnostopoulos et al. (1990), Fukuoka (1977) and Matsui et al. (1988). The point of application of the sliding force was explored based on successful case histories while addressing the safety factors for both geotechnical and structural design, Vessely A. et al. (2007). The development of numerical analysis techniques utilizing the method of finite elements (FE) also enabled better analysis and design of slopes stabilized using piles. A FE-based approach was successfully utilized to design slope stabilization with target safety factor based on the shear and bending demands and the spacing of the piles, Pradel D. et al. (2010).After Hurricane Sandy in October 2012, the stability of many properties constructed atop earth slopes located along the coast of the Atlantic Ocean has become a concern due to storm-induced erosion. This paper presents the analysis, design and construction of a hybrid slope stabilization system utilized at one of these storm-impacted properties, which is located in the Atlantic Highlands, New Jersey in the United States. The subject property consisted of a two-story residential dwelling and a parking structure, and was built on top of an about 8-m-high earth slope having crest at about elevation 10 m (el 10) and toe at about el 2."

Jan 1, 1900

By Timothy Nelson, Simon Burnworth

"The University of California’s new Berkeley Art Museum and Pacific Film Archive will showcase a collection of art and film in a facility that pairs an existing 1930s-era printing press facility with a new, architecturally unique auditorium wing. The centerpiece of this adaptive-reuse project is the existing 3- story art-deco Administrative Building, which will be integrated into the new museum and provide approximately 18,000 square feet of usable space. Degenkolb Engineers, as the shoring engineer of record, along with Condon Johnson & Associates Inc., the shoring contractor, worked together with general contractor Plant Construction Company to design and build a temporary structure to facilitate the complex retrofit, renovation, and expansion of the Admin Building. This paper will discuss the challenges faced by the design and construction team, the sustainable solutions implemented on the project, and the collaboration between teams to meet the unique constraints of the project and the site.INTRODUCTION AND PROJECT BACKGROUNDThe Berkeley Art Museum and Pacific Film Archive (BAMPFA), which currently resides in a 1970s-era post-modern concrete structure just south of the University of California Berkeley (UCB) campus, was in need of a new home after an engineering evaluation revealed that the building possessed seismic deficiencies. Pressed for space, the University looked within its portfolio of properties and identified the site of the former University Printing Press facility as the place to build BAMPFA’s new home."

Jan 1, 2017

By Sara Anderson, Rachel Nicholls, Tim Chapman, Janice Windle

"In city center sites around the world, and in particular in London, foundation reuse is becoming increasingly widespread as the ground is filled with detritus from previous developments. This paper sets out a systematic framework to consider the need for and benefits of foundation reuse and key issues to be resolved for foundation reuse to be successfully adopted on redevelopment projects. Once foundation reuse has been identified as a potential foundation solution there are several key stages in the design and construction process where the decision to reuse foundations needs to be assessed. The paper concludes by emphasising the importance of ensuring that the foundations being installed now can more easily be reused in the future.INTRODUCTIONThe concept of re-using foundations is not new, and has been adopted on an isolated project-byproject basis for many years. However, over the past decade, interest in the potential of reusing existing piles and caissons within Europe has increased significantly, with a growing interest in the United States of America and Japan. The need has been driven by necessity: on many urban sites the space available for new foundations diminishes with each new set of piles, and these problems can only grow in the future.Initiatives such as the European Union's RuFUS (Re-use of Foundations for Urban Sites) research project have resulted in identification of the key issues for technical viability and risk that have previously hampered potential foundation reuse projects.There is a need to define a systematic approach to the reuse of foundations so that the risks associated with reuse can be identified, managed and mitigated. This requires improvements in knowledge to provide confidence in the long term behaviour of the foundation support and address the risks involved in reusing existing foundations to overcome perceived obstacles in making foundation reuse a realistic option for many sites."

Jan 1, 2005

By Adnan A. Malik, Tadashi Maejima, Jiro Kuwano, Shinya Tachibana

"The helical piling system provides solution to many geotechnical related problems due to its quick installation, higher compressive and pullout resistance, no wastage of material, workable in limited areas and reusability. However, its use as a foundation for bridges and high-rise buildings is still limited as compared to other piling methods. In the present study, the performance and load settlement behavior of screw and straight pile is investigated under cyclic compressive load in dense ground conditions. To achieve the set objectives, pile load tests were conducted in a cylindrical steel container. The model ground was compacted with dry sand at relative density of 80%. It is observed from the test results that screw and straight pile resistance reduced when the cyclic load is applied at allowable pile resistance state. The reduction in the ultimate pile capacity is more in straight pile than in screw pile. However, straight pile showed higher ultimate pile capacity than screw pile under similar pile tip diameter. The effect of helix bending deflection on load settlement behavior and ultimate pile capacity increases under cyclic loading.INTRODUCTIONScrew pile is one of the new developments in deep foundation, which is growing tremendously fast because of its quick installation technique, less noisy operation, no wastage of material and involvement of minimum manpower. Screw piles have an edge on straight pipe piles due to its high bearing capacity and uplift resistance. The installation mechanism of screw pile is different from straight pile. Torque and pressure is required to install the screw pile whereas hammering, pressure and vibration is required to install straight pile. As the installation mechanism is different between screw and straight pile, therefore, the ground disturbance that is produced during their installation is also different. The ground disturbance produced during the installation also depends upon the pile tip condition i.e. open or closed ended. Sakr, (2009) stated that the compressive capacity of screw pile in 3 to 5 times higher than driven piles having the same shaft diameter and length. The reason for this increase in pile capacity is due to helix, which is generally 2 to 2.5 times the pile shaft diameter. Larger helices can give higher end bearing capacity but it requires very powerful machinery to install in dense grounds. For instance, if large helix screw pile is installed in a dense ground then helix-bending deflection will start affecting the end bearing capacity (Yttrup and Abramsson, 2003; Malik et al. 2013 and 2015). According to Malik (2015), the equations of thin plate (Young and Budynas, 2002) with uniformly distributed load on the plate can give reasonable estimation of helix deflection due to dense ground conditions."

Jan 1, 2016

By Ali Nasirian Ph. D., Gabriel Carvajal

To facilitate the safer and more secure transportation of inmates from San Diego Central Jail to the new San Diego Courthouse, the County of San Diego committed to building a new transfer facility as part of the downtown developments. The transfer facility includes a three-story underground structure adjacent and connected to the Central Jail and a 60-ft deep, 23-ft diameter, 320-ft long tunnel. The tunnel starts at County Jail, passes underneath Western Regional Detention Facility (Old Jail) and, ultimately, connects to the State Courthouse. Condon-Johnson & Associates, Inc. (CJA) was selected to install the temporary shoring shaft for the underground structure as well as three arrays of canopy pipes to support the tunnel’s Sequential Excavation Method (SEM) construction. CJA installed the rectangular 56-ft deep access shaft shoring with three levels of bracing, and a combination of secant piles, soldier piles, and timber lagging. The shoring also included a sliding bridge at top to provide access for trucks to enter and exit from county jail during the duration of construction. Following shoring and shaft excavation, CJA installed and grouted 7-5/8” dia. canopy pipes in 3 reaches, parallel to the longitudinal design line of tunnel with a slight lookout angle. CJA installed 24 each canopy pipes, 99-ft from face of shaft at reach 1, 21 each, 80-ft length canopy pipes at reach 2, and 21 each, 75-ft length pipes at reach 3. CJA confirmed canopy pipe alignment via Inertial Sensing Gyro. To mitigate the possibility of settlements caused by the tunneling operation underneath Old Jail strip footing and grade beams, CJA also performed void fill grouting. Sleeve port grout pipes (SPGP’s) were installed inside the Old Jail basement and grouted with the use of packers as the tunneling operation passed underneath the Old Jail. In detailing various aspects of the construction, this paper aims to magnify the innovative solutions for shoring, canopy pipe installation and void fill grouting challenges as well as the state of the art quality control measures undertaken by CJA.

Oct 1, 2022

By Arash Khosravifar Ph. D. P. E., Thomas Torkelson P. E., Milad Souri Ph. D. P. E.

Kinematic demands from lateral ground deformations can be a major cause of damage to maritime and highway transportation structures such as wharves, piers, and bridges. These kinematic demands are different from the ground deformations in the free field in that the resisting forces from piles will reduce the ground deformations to some extent (i.e., pile pinning effect). Current design codes for wharf structures allow the beneficial resisting forces from pile pinning effects to be incorporated in pseudostatic slope stability analysis (e.g., ASCE/COPRI 61-14). While design guidelines that are specifically developed for bridge foundations provide recommendations on how to incorporate the pile pinning effects (e.g., Caltrans 2012), their applicability to wharf structures need to be evaluated. This study uses the results of a large-scale centrifuge test on a pile-supported wharf structure to evaluate the accuracy of available Newmark sliding block analysis in estimating the lateral ground deformations. Pile pinning effects are incorporated based on the approach outlined by Caltrans. The results of this study support the use of existing pile pinning methods that were primarily developed for bridge foundations in maritime structures (e.g., wharves and piers). It was found that median Newmark displacements provide a good estimate of the permanent end-of-shaking displacements and that the median plus 1 standard deviation Newmark displacements provide a good estimate of the peak transient displacements. Design considerations for use in the Newmark sliding block analysis to estimate the kinematic demands on piles are discussed.

Oct 1, 2022