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By Stephen Slomski, Benjamin White, Bradley Klausing

Integrity assessment of drilled shafts can be determined by considering information from many points in the construction process. Observation of the drilling and shaft installation can provide additional confidence in the foundation element. Material testing is commonplace and provides another quality assurance. This information should be considered and is critical to the final evaluation of shaft integrity. Integrity testing is an in-situ method that evaluates the shaft as constructed. Several testing methods, each with its own strengths and limitations, are available to evaluate the integrity of a shaft. This article discusses three types of tests, thermal integrity profiling, low-strain integrity testing and high-strain dynamic testing, and their results from drilled shafts installed to support two county road projects.

Jan 1, 2025

By Jason Reinhardt, Devon Switser, Nick Strater, Bob Stier, Joseph Reed

Originally constructed from 1828-1850, the Chesapeake & Ohio (C&O) Canal was one of the first largescale civil works projects funded by the U.S. Government, with supplemental funds from Mary- land and Virginia. The canal's navi- gational system stretched along the Potomac River for 184.5 mi (296 km) from Washington, D.C., to Cumberland, Maryland. The C&O Canal's navigational system was primarily comprised of locally sourced materials such as stone, earth, timber, mortar and brick. The Paw Paw Tunnel was con- structed by the C&O Canal Company in lieu of building 6.7 mi (11 km) of canal along the Potomac River (referred to as the Paw Paw Bends). The tunnel is approximately 3,118 ft (950 m) long, 25 ft (8m) wide, lined with six million bricks, and included open cuts through the interbedded shale and siltstone on both sides of the approaches to the tunnel en- trances. The excavation passed through the Tunnel Hill Ridge and the Valley of Mill Run (a stream that still conveys water through the cut in the form of waterfalls). After the full section of canal through the project area was opened in 1850, it remained in commercial oper- ation for 74 years until 1924. Today, the Paw Paw Slope Stabiliza- tion Project is located in one of the most remote portions of the Chesapeake & Ohio Canal National Historical Park, approximately 155 river miles (250 km) upstream of Washington, D.C., and under the management of the National Park Service. There is a rich history of rock fall and slope instability within the cut on the downstream approach to the tunnel. This is due to a combination of

Apr 1, 2025

By Andrew Lees

Where in-situ ground is too weak to support piling rigs and other mobile plants, a temporary platform of stronger granular material may be constructed to distribute plant loads safely to the underlying ground. A critical step in the construction of a safe working platform is its design. Essentially, the optimal thickness of the platform material needs to be determined such that it is large enough to distribute piling rig track pressures safely to the ground without bearing failure, but not so large that it becomes unnecessarily expensive and time-consuming to construct. Platform failure can take several geotechnical forms including punching shear failure through the platform into the underlying soil and a rotational slip failure. Any, or a combination, of these could lead to platform failure and a catastrophic toppling of a piling rig. Safe design of these temporary struc- tures requires a calculation method that can cover these failure modes in a reliable manner. The T-value calculation method considers multiple failure modes since it is derived from validated finite element analysis (FEA) that has no predetermined failure modes. Since its introduction in 2019, it has been applied to the design of hundreds of working platforms around the world. On its fifth birthday, the method's author provides a quick overview and advice on its use.

Jan 1, 2025

By Dimitrios Konstantakos

When writing this article almost 10 years ago about the future of the deep foundations industry, little did I have in mind that ChatGPT would be created. Nevertheless, the mere act of writing up the article created a spark within me to prep up for what was coming. So, we put together some form of natural language communication with our deep excava- tion software, and although cumber- some, we could voice command it. When ChatGPT came to being, this allowed us to create the first AI assistant for generating deep excavation models. In November, we are releasing the first AI system for predicting pile capacity, which was one of the items described in the original article.

Jan 1, 2015

By Matthew Conte

Overgrown vegetation. Little to no effective drainage. Three or four different construction methods over the years. Live loads from above. Property line to navigate. Buildings on either side. I drove by this site for years wondering when someone was going to have to deal with it. That day came, and it turned out to be us. This particular project had typical attributes: limited space and restrictive conditions. This retaining wall system supported the neighbor's parking lot above, roughly 14 ft (4 m) in elevation change. At a length of 92 ft (28 m), both ends of the wall abut an active building in the lower property. Only a small parking area of roughly 50 ft (15 m) in depth lies before the heavily traveled state route in Westport, Connecticut. Roughly two-thirds of the existing wall was tiered, and the other third was taller, with a concrete masonry unit (CMU) wall that appeared to be part of a former structure. The existing wall was failing and leaning over the parking spaces. The drainage system showed signs of failure, and the vegetation was clearly retaining moisture and frost was heaving the walls a little more each year. During the initial kick-off of the project, it was decided we would immediately shore up this taller portion of the existing wall. That shoring would stay in place through construction. With active tenants and neighbors, the property owner needed a solution that would allow businesses to stay open and limit any disturbance to the above property. Very little documentation existed showing the construction of the walls or the soil conditions. Above, the neighboring property had added a small retaining wall when its parking lot was constructed. Soil borings were found, but nothing showing details on that newer retaining wall. The borings indicated structural fill was compacted in lifts beneath the lot, but nothing indicating any geotechnical measures beneath the wall, at the property line. We were forced to design a new wall considering the 'worst case' conditions. This new wall also required construction methods that would allow all aspects of the surrounding area to remain intact.

May 1, 2025

By Yasir Husain, Deepankar Choudhury, Hamzah M. B. Al-Hashemi, Marwan Alzaylaie

An existing warehouse spanning 12,000 sq m (130,000 sq ft), located in Jazan City on the southwestern coast of the Red Sea in Saudi Arabia, was supported by a reinforced concrete slab- on-grade, while its steel columns stood on bored piles and pile caps. Completed approximately a decade ago, the structure developed severe cracking and floor deformation reaching up to 170 mm (7 in), as per recent site surveys. The deformation evolved without any progressive instrumentation or moni- toring in place, and thus, neither the onset nor the time- dependent behaviour of the issue could be precisely estab- lished. The warehouse remained operational throughout this period, and the owners, faced with ongoing challenges, decided to announce a public bid inviting contractors and con- sultants to propose a feasible rehabilitation solution, given the unique nature of the site and the ongoing operations. To begin with, the city of Jazan is not an easy geotechnical ground to conquer. The region is defined by complex and problematic ground conditions: collapsible loess soil, Sabkha deposits (salt flats), salt domes (which are highly deformable over time), organic expansive clays, flood-prone zones, extreme temperatures, aggressive environmental effects and moderate seismic activity. Salt domes are large underground formations of salt that have pushed upward through overlying layers of rock due to their lower density. Over time, they can deform and shift, causing ground instability at the surface. These structures are particularly problematic for foundations, as the salt can dissolve with water infiltration or move plastically under stress, leading to uneven settlement or sudden subsidence of built structures. Furthermore, the structure in question had to remain in service, limiting the options for rehabilitation due to spatial, operational and construction-related constraints.

Aug 1, 2025

By Bengt Fellenius

I remember the 1983 conference and this "DFI News" note with its summary of my lecture - and how I cringed on seeing the heading of the note, claiming that I had "released the wave equation." The WEAP (wave equation analysis of pile driving) had been "released" about a decade earlier by the founders of GRL Engineers and Pile Dynamics, George Goble and Frank Rausche, marking the beginning of their great contributions to the geotechnical engineering practice "the quantum leap." I appreciate the opportunity, now 40 years later, to correct the heading implication. Several typos in the note, then irritating, are now more amusing, such as, "dull complex" instead of "full" and "restriction" instead of "restrike." My lecture tried to introduce some of the then recently developed dynamic monitoring and analysis state of the practice: the WEAP and PDA/CAPWAP (Pile Driving Analyzer/CAse Pile Wave Analysis Program). The lecture and the notes should be read in the light of how they were operated in early years. The mainframe computer and input was by means of punch cards. The field testing using the PDA was by lugging the analyzer, a bulky tape recorder, an oscilloscope, and power-cable and gage-chord bundles to the site. If travel was by air, the analyzer sat on the seat next to the engineer. For assessing the pile in the field, the measurements were printed out on a paper roll. In the mid-1980s, a screen was added to the analyzer, it became digital, and data were stored and accessible electroni- cally also in the field. No more tape recorder and oscilloscope. At about the same time, the PC arrived and the WEAP became available for running on the office machine. Process was slow; while the PC ran a WEAP, it was time for a cigarette and a cup of coffee. To think through the input to the analysis, there- fore, became an important time-saving effort. Soon thereafter, the CAPWAP also became available for use on a PC. The first International Stress Wave Conference in Stockholm in 1980 (it continued every fourth year, thereafter) started the international acceptance of monitoring. At the third conference, in Ottawa in 1988, the number of indi- viduals outside of GRL performing CAPWAP analysis amounted to 17, with 14 from outside the U.S. Today, the high-strain dynamic monitoring is routine wherever piles are driven, and its use has been extended to testing non-driven piles. The wave equation and high-strain dynamic method, then and now, is for assessing pile-soil response in terms of pile capacity and hammer perfor- mance. Over the years since, it has been extended to low-strain integrity testing and current advancement of tech- nology has been incorporated. For example, the connection between pile gages is now wireless and the analyzer is a tablet. The pile monitoring data can be sent to the "cloud" and enable remote testing. The process is so fast that an automatic signal matching can be made in real time on every blow. At some sites, every pile is tested, thus, the method is used for continuous quality control of the hammer-pile-soil system.

Jan 1, 2025

By Manny a. Fine

Manny Fine, who was once my boss and mentor, provides a sentient account of the perils of the specialist foundation subcontractor in a world of public sector design-build contracting. He opens by relating the comfort foundation specialists have with the private sector design-build model. A model that, he states, enjoys the freedom of innovation with what is believed to be a genuine interest and flexibility in concept, receptivity and contract in the private sector, which has led to public sector interest and dabbling in the design- build delivery method. Fine then describes a public sector arena for design-build fraught with difficulty for the specialist foundation subcontractor, which includes great effort for low return, contract restric- tions, narrow interpretation of alter- natives, and a low flexibility by the owner for alternative methods and risk assumption. His conclusion is that the design-build delivery method in the public sector results in duplication and wasted effort by the foundation specialist(s). He deems the evaluation process to be unsophisticated and lacking the ability to select the best proposal in terms of solution and or cost benefit and that the owner needs "to find ways to be more receptive to alternative or value engineered proposals." Now, 27 years later, we witness a well-established and flexible private sector design-build market driven by specialist foundation contractors and their partner consultants that has welcomed new technologies and driven innovation. Typically, there is more definition to the small- to medium-sized private projects (up to $15 million in value), whereas large design-build projects often see early contractor input and a team selected during the design process. The success of public sector design-build delivery has increased significantly since the time of Fine's commentary with many very suc- cessful applications and new 'models

Jan 1, 1998

By S. Harteis, D. Dolinar

Many mining operations rely on bulkheads to provide a barrier between impounded water or slurry and active mine workings. However, bulkhead failures could cause and have caused catastrophic flooding that puts the underground workforce at risk. The National Institute for Occupational Safety and Health1 (NIOSH) in collaboration with the Mine Safety and Health Administration (MSHA) is conducting research to evaluate the adequacy of existing design practices for water and slurry bulkheads. A key component of this research effort is documentation of the performance history and design parameters for bulkheads installed in underground coal mines during the last 20+ years. This research is part of a larger effort to develop general design guidelines and procedures for constructing and maintaining bulkheads that will help to ensure their long-term structural integrity, while significantly reducing the inundation risk for miners. This paper presents the results of NIOSH’s research to identify state-of-the-art bulkhead designs, including design criteria, leakage monitoring systems, and emergency warning systems. Underground observations and evaluations of existing bulkheads suggest that the most important design factors influencing their performance are the interface of the bulkhead with the surrounding strata and the potential magnitude of the hydraulic pressure to which they may be subjected. When a bulkhead has failed, leakage has generally been through the surrounding strata or along the bulkhead/strata interface, with the failure potential along the interface increasing with hydraulic head. It was also determined that development of a monitoring program to ensure the long term structural integrity of bulkheads is an important safety consideration. Current monitoring procedures range from weekly visual inspections to constant monitoring via pressure transducers and fluid level indicators. Where possible, these devices are used in conjunction with a computer based mine monitoring system to alert mine personnel when an emergency condition exists at the bulkhead installation.

Jan 1, 2006

By Fatemeh Pariafsai, Ali Doostvandi

To assess the stability of a soil slope considering uncertainty in soil characteristics (C, Φ), it is necessary to conduct repeated calculations to determine both the Factor of Safety (FS) and the Probability of Failure (PF). The absence of analytical solutions leads researchers to use surrogate approaches of probabilistic modeling. This study aims to assess the PF and FS of a saturated soil slope using one of the Machine Learning (ML) method subsets, the regression Least Squares Support Vector Machine (LS-SVM). The results are compared to those obtained from the Limit Equilibrium Method (LEM) to compare the accuracy of LS-SVM. According to the FS-PF plot, it is concluded that LS-SVM is a reliable tool for determining the stability of a multi-layered saturated soil slope, which significantly improves computational efficiency. Furthermore, since predicting FS and PF from field data requires fewer data points, it will result in significant time and cost savings. However, to avoid false predictions, limitations must be removed, for instance, each layer should be included in the analysis within its probabilistic distribution, so using this method is more efficacious in clay soils where there are values for cohesion, unlike sands (c=0). This helps training data to be prepared well and to prevent misprediction in local failures. In addition, training data are debated in terms of the percentage employed. Furthermore, showing the importance of dataset scattering is concluded that adopting data with uniform distributions plays a crucial role in preparing training data sets and consequently, in having a better prediction of the possible slope failures.

Oct 7, 2024

By Sarah Banks

"Here and there the grease and filth have caked solid, and the creek looks like a bed of lava; chickens walk about on it...and many times an unwary stranger has started to stroll across, and vanished temporarily." Upton Sinclair offers this revolting - yet accurate - description of the Chicago River in his book The Jungle, originally published in 1906. In the early 1900s, Chicago was a major industrial hub. The Chicago River was not only heavily used for transportation but also for the disposal of waste produced by the meatpacking industry, steel production, rail manufacturing and more. The South Fork of the river was the primary sewer for the Union Stock Yards. The meatpacking industry caused so much pollution, the river became known as Bubbly Creek. Chicago's older buildings were designed to be shut off from the river - no windows, certainly no homes or parks. A river view from an office or hotel was not something to brag about. It wasn't until the 1970s and the passage of the federal Clean Water Act that things began to change. The city now requires public access to the river in all parts and newer architectural designs ensure this is possible. Rather than sewage and industrial waste, the river now carries boat- loads of tourists and kayakers.

Oct 1, 2025

By Shawna Munn, Katie Castelo, Dave Wiley

Risk is inherent to work in the field of subsurface engineering, and many contract approaches have become so focused on shedding risk that they leave no room for one of the best tools in our industry, the observational method. Its development in subsurface engineering owes its foundation to Karl Terzaghi and Ralph Peck through their respective works dating back as early as Soil Mech- anics in Engineering Practice published in 1948 and "Advantages and Limitations of the Observational Method in Applied Soil Mechanics" in 1969. Throughout their fundamental works, a strong argu- ment for the observational method is made: "... the potential for savings of time and money without sacrifice of safety is so great that every engineer who deals with applied soil mechanics needs to be informed." (Peck 1969) Not every project will benefit from its use, but in today's risk management focused world, projects and contracts should be set up to allow for its use, while sharing the risk clearly and equitably between all parties. Without a proper contractual mechanism to leverage its use, perceived manage- ment of "risky unknowns" will over- ride substantive application of the method, and significant benefits may be lost as a result. As Terzaghi said, "A vast amount of labor goes into securing only roughly approx-imate values for the physical constants that appear in equations Therefore, the results of computations are not more than working hypotheses, subject to confirmation or modification during construction." It is our collective view that sub- surface engineers should take this task of confirmation and modification seriously. We should use the observa- tional method to derive performance- based designs that deliver design economy, constructability, cost and schedule advantages without sacrificing safety or quality. Collaborative style contracts provide a framework to approach shared risk and opportunity with appropriate incentives for the individual parties.

Aug 1, 2025

By Marya Gorczyca, Damian Siebert

Air rights projects are inherently challenging as they involve building in the "air space" above an existing structure. From a foundation engineering and installation standpoint there are numerous constraints and additional complexities to consider. This article describes how these issues were overcome for deep foundation design and construction at Lyrik Back Bay - Air Rights Parcel 12, the first successful air rights project over the Massachusetts Turnpike/Interstate I- 90 through this neighborhood in downtown Boston in 40 years. The project is unique in that it is both an infrastructure and commercial development project undertaken as a collaboration between a private development team S&A P-12 Property led by Samuels & Associates, and the state transportation agency, the Massachusetts Department of Transportation (Mass DOT), owner of the land and transportation infrastructure.

Oct 1, 2025

By Erik Westerberg, K. Rainer Massarsch

The paper was presented 30 years ago at DFI's 20th Annual Conference in Charleston, South Carolina, in 1995. Its main objective was to describe the operation and performance of vibrators with variable frequency and to illustrate their practical application in foundation engineering. Since then, powerful vibrators with variable frequency have been increasingly used in the foundation industry for installing/extracting piles or sheet piles, treating granular soils to decrease total and differential settlement, or mitigating the liquefaction hazard. However, the potential of variable frequency vibrators for pile installation. or ground compaction has not yet been fully realized. By adjusting the operating frequency of the vibrator, the penetration/extraction speed of piles or sheet piles can be increased signifi- cantly. At the same time, the emission of ground vibrations can be minimized. Some recent important developments for efficiently using vibrators are briefly summarized below. An important aspect of vibratory driving is "system resonance," at which the vibrator and the probe oscillate "in phase" with the surrounding soil. The relative displacement between the probe and the soil decreases during this phase. Probe penetration slows down, and ground vibrations increase. To effectively install piles or sheet piles in granular soils, the vibrator should be operated at a high frequency (typically above 30 Hz). The vertically oscillating pile emits horizontal stress pulses that are transmitted to the ground. This mechanism reduces the shaft resistance during driving in granular soils. Con- sequently, the shaft resistance of vibrated piles is often lower than that of impact-driven piles, the impact of which, by definition, occurs at res- onance of the pile-soil system. However, the shaft resistance of vibrated piles can be enhanced if, during the final phase of installation, the operating frequency is gradually lowered to achieve com- paction of the soil surrounding the pile shaft. It is also desirable that the vertical movement amplitude of the pile be gradually reduced to eliminate the formation of a gap below the pile toe. Electronic monitoring systems are available to assist the machine operator in determining system resonance dur- ing driving. Vibration sensors mounted on the vibrator or on the ground can determine, monitor and adjust the resonance frequency. Nowadays, ro- bust electronic systems can display the measured values to the machine operator and the geotechnical engineer on-site or in the office.

Jan 1, 1996

By Peter Faust, Mike Muchard

The I-205 improvements in Oregon include the seismic retrofit and widening of the Abernethy Bridge to withstand major earthquakes. When completed it will be the first earthquake-ready bridge that crosses the Willamette River in the Portland metropolitan area; establishing it as the regional north-south lifeline route after a disaster. To meet seismic performance goals, critical bridge piers were retrofitted with very large and deep nonredundant (single) drilled shafts with "outrigger" bents. New drilled shafts and columns were constructed on both sides of these piers supporting a new post tensioned "super beam." While the drHled shaft scope of the project is now finished, construction is still underway for the project, which is due for completion in 2025. Once the load is transferred to the new outrigger bents, the existing columns will be removed. Drilled shaft diameters for the river crossing ranged from 8.2-12.25 ft (2.5-3.7 m), with the largest shafts extending over 240 ft (73 m) in length. This size drilled shaft surpasses the typical dimensions used for transportation structures. Given the enormity of these shafts, combined with the complex geology and site constraints, the Oregon Department of Transportation required a prequalification process to select the foundation contractor, Malcolm Drilling.

Jan 1, 2025

By Morgan Eddy, Andy Steele

With its rich history and rapid urban development, the Mount Vernon Triangle neighborhood in Washington, D.C., is ready to welcome a new addition: Claret, a 12-story, 127- condo residence. Tasked to maximize below-grade space for the new development, Steelle Foundation converted an existing parking lot by excavating up to approximately 30 ft (9 m) deep. The team navigated many challenges, including proximity to an adjacent building, limited access to the site and a mandate to preserve a century-old Heritage Tree. a specialized foundation engineering approach. The catalyst for the project was the growing demand for high-quality residential spaces in the area, combined with the site's strategic location.

Mar 1, 2025

By Robert Tonning

Boston's Landmark Center, a historic site in the Fenway neighborhood, is undergoing a major transformation. Originally built in 1928 by Sears, Roebuck & Company, the building is being repurposed into a mixed-use development that will breathe new life into the structure while preserving its historical significance. A key aspect of Historic photo of Bo this project is the deep foundation system, which employs drilled micropiles. While these have been commonly used on construction projects for the past several decades, these truly "super piles" pushed con- ventional limits of both drill depths and working capacity in order to meet the project's requirements. The installation of these micropiles presented several challenges, from extreme depths and high capacities to tight timelines and complex site conditions. This article explores the engineering feats, challenges faced and innovative solutions that were developed and implemented throughout the process. Thanks to creative problem-solving and collaboration with the wider pro- ject team, Phoenix completed its work as a geostructural subcontractor ahead of schedule. The Landmark Center has a rich history in Boston's Fenway neighborhood. Before the present building was constructed almost 100 years ago by Sears, the site had been home to a number of factories, warehouses and other industrial buildings dating back to the late 1800s. The location was also near the former Fenway Railroad Yard, a modest transportation hub that served the surrounding area at the turn of the 20th century.

May 1, 2025

By Keshab Sharma, Jibendra Misra

Caissons and piles are mostly used as foundation types in bridges. Caissons are particularly suitable for bridges with expansive spans, locations with deep alluvial deposits, soil prone to lique- faction and when there's a notable risk of vessel collisions. However, they face challenges related to sinking and limited resistance against earthquakes. On the other hand, pile foundations are not well suited for deep-water scenarios due to their excessive length, diminished rigidity, susceptibility to vessel col- lisions and complications associated with construction. A potential solution to the issues mentioned above could be the adoption of CCPF. These foundations can also be applied to enhance existing caisson. foundations through retrofitting techniques in wind turbines, trans- mission lines and bridge foundations, demonstrating their adaptability and potential for improving the perfor- mance of foundation systems. There has been successful implementation in China, as evidenced by projects like the Qiongzhou Straits Bridge and the Longna Highway Yangtze River Bridge. Moreover, this foundation approach has been adopted for numerous cross- sea bridges globally, including ex- amples like the Benicia Martinez Bridge (U.S.) and the Hitsuichi-Jima Bridge (Japan). Research from 2016 has shown CCPF systems can be potentially used for offshore wind turbine foundations and retrofitting existing caisson foundations. The construction sequences of CCPF systems involve the sinking of caissons followed by driving the pile beneath the caisson. There are two possible options for connecting the pile with the caisson. The first option can be provided by ending the pile at the bottom plug level of the caisson, in which the pile is threaded into the caisson bottom to achieve a connection joint between the caisson base and the pile tops. This methodology enhances the flexibility of the foundation. The second method is to continue the pile up to the cap level of the caisson. The pile up to the cap level of the caisson provides better integrity than the first option between caisson

May 1, 2025

By Matthew Meyer, Rosa Castro-krawiec, Charles Bartlett

The PortMiami Tunnel project stands as an engineering milestone in Florida, marking the first large-diameter tunnel designed and constructed in the state. As we celebrate Deep Founda- tions Institute's 50th anniversary, it's apropos to revisit this groundbreaking work, first documented by Matthew Meyer, P.E., Rosa Castro-Krawiec, P.E., and Charles Bartlett, P.E., in the January-February 2012 edition of Deep Foundations magazine. Their account details the project's formidable chal- lenges and the innovative solutions that led to its success. Completed in 2014, the PortMiami Tunnel project was a monumental undertaking to alleviate commercial traffic congestion in Downtown Miami. The tunnel links the interstate high- way network to PortMiami in Biscayne Bay, easing city traffic while boosting cargo and cruise ship capacity. This project was not just a feat of engineer- ing but a catalyst for economic growth and regional development. One of the project's most remark- able aspects was its pioneering use of advanced ground improvement tech- niques, particularly deep soil mixing (DSM) for support of excavation (SOE) and groundwater control. Miami's geotechnical conditions presented a unique set of challenges, including highly permeable subsurface materials and high static groundwater levels. Traditional excavation methods were deemed too risky and costly, necessi- tating creative solutions. To launch and retrieve the 40 ft (12 m) diameter tunnel boring machine that was required to construct the tunnel, the project team opted for cutter-soil-mix walls with embedded.

Jan 1, 2012

By John Morris, Scott Stonecheck

The University of Pittsburgh wanted a new arena constructed for its collegiate wrestling, volleyball, and gymnastics, dance and cheer programs. Due to space constraints for the arena in the university's congested urban setting, the school selected a location atop a previously demolished football stadi- um originally constructed in 1925. The new Victory Heights Arena and Sports Performance Center is nestled between the Peterson Events Center, student residence buildings Panther and Irvis Halls, and other critical campus infrastructure. Due to the site's con- straints, a permanent tied back soldier beam wall system was programmed for the subterranean portion of the arena's perimeter foundation wall, with the soldier beams and tiebacks using a delegated design-build approach and the permanent wall facing being designed by the building's structural engineer of record. Design and construction of the soldier beam wall system required a mix of conventional and unique approaches to address topographical, geological and site challenges. This article will provide an over- view of the approaches to the various challenges, the design concept, effi- ciencies gained through the design assist strategies employed through the early phase of the project, and lessons learned from site and geological dis- coveries uncovered and safely over- come during the physical work.

Mar 1, 2025