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By Joel Moskowitz

A new office complex is being constructed within 25m of the Hudson River in New Jersey. The project, about 140 m by 100 m, will include 4 basements under the entire footprint. The perimeter was to be secured by a 0.8 m thick diaphragm wall, laterally supported by high capacity tieback anchors to rock. Columns were to be supported on footings or piers to rock at a nominal bearing pressure of 3.8 MPa at depths up to 17m. Although some variation in rock quality was observed in borings, a substantial vertical seam of weathered and/or decomposed rock, 1 to 2 meters wide by as much as 8 meters deep, was encountered during construction necessitating field redesign. In some locations the seam dipped below more competent rock. Footings were redesigned for support on drilled caissons, or soft rock was excavated and replaced with concrete necessitating a reduction in bearing pressure of the footings by one half.

Jan 1, 2002

By Shahriar Vandani, Andy Herlache, Andrew Bro, Wei-Yu Chen

"The Presidio Parkway Project will reconstruct approximately 1.6 miles (2.6 km) of highway, including seven new bridges, three new cut-and-cover tunnels, and a new undercrossing connecting the Golden Gate Bridge to the City of San Francisco, California. The project site is approximately 5.6 miles (9 km) from the San Andreas Fault, capable of producing magnitude 8 earthquakes. Seismic hazards include strong ground shaking, soil liquefaction, ground settlement, and lateral spreading. The Main Post Tunnels (MPT) are two parallel cut-and-cover concrete tunnels approximately 1100 feet (335 m) long. The MPT site underlain by loose sandy soils susceptible to liquefaction and lateral spreading. Excessive racking and permanent displacement due to lateral spreading are identified as the main seismic vulnerabilities. Analyses showed that without ground improvement, tunnel racking of over 5 inches (13 cm) and permanent lateral tunnel displacement of up to 15 feet (4.6 m) could be anticipated. Cement Deep Soil Mixing (CDSM) is proposed to mitigate slope displacements and increase lateral stiffness of the foundation materials to reduce tunnel racking. A series of 2-D fully dynamic time domain analyses were performed to evaluate the performance of CDSM, confirm that performance criteria are met, and optimize the CDSM geometry and replacement ratio. The use of CDSM reduced the permanent tunnel displacement from over 15 feet (4.6 m) to less than 1 inch (2.5 cm). Tunnel racking was also reduced significantly. The adopted analytical approach presented herein can be considered for future tunnel design projects in seismically active areas.Introduction The Main Post Tunnels (MPT) are an integral component of the Presidio Parkway project which will replace the existing facility with a new multi-lane roadway between the Golden Gate Bridge and the City of San Francisco. The MPT are two parallel cut-and-cover concrete tunnels approximately 1100 feet (335 m) in length. As shown on Figure 1, the project site is located in a seismically active area, about 5.6 miles (9 km) east of the San Andreas Fault and 12.5 miles (20 km) west of the Hayward Fault. The San Andreas Fault can generate magnitude 8 earthquakes while the Hayward Fault is capable of producing magnitude 7.3 earthquakes. The design Peak Bedrock Acceleration (PBA) is 0.46g for the upper level design earthquake. The project alignment is shown on Figure 2."

Jan 1, 2014

By K. Law

"The Hatch Product Transport (HPT) system is a highly flexible and configurable route selection and sequencing system for controlling large bulk material handling facilities. The system has a generic control algorithm that can be configured to suit any material handling facility. It can also be easily reconfigured to cater to plant expansion or modifications without incurring significant disruption to the existing production, costs in testing, and re-commissioning, thus achieving cost savings throughout a facility’s lifecycle.This new material handling control system has been installed at BHP Billiton’s Port Hedland iron ore terminal to facilitate its expansion to beyond 100 Mt output capacity."

Jan 1, 2006

By Chandramohan P. V., Ravi Kishore

"An underground reservoir was to be constructed at Doha in Qatar. Simsima lime stone is present at the bottom. When the reservoir is empty, there will be uplift at the bottom but this will change to downward load when it is full. The rock at the bottom had high bearing capacity to resist downward load. But uplift had to be resisted by piles or anchors. The reservoir has a size of 120mx80m. Shrinkage and creep of concrete coupled with thermal contraction imposed a horizontal movement of 26mm on the extreme piles. So, piles have to accommodate this as well. This unique situation needed a unique solution. The solution was to provide piles with flexible high tensile strands to take tension. An annular space near the head of the pile would facilitate horizontal movement as well. Compression load was directly passed on to the raft bearing on rock.INTRODUCTIONAn underground reservoir for storage of drinking water was to be constructed at Doha, Qatar. The reservoir was proposed to have a plan size of 120m x 80m. Clear height inside the reservoir was proposed as 17.2m, from the bottom of roof to the top of bottom raft. Overall height of the reservoir at the outlet from the top of the roof to the bottom of raft was to be 21.2m. For the sake of inspection and in order to prevent pollution from the surroundings a gallery was planned around the reservoir. This could accommodate pipelines as well. This gallery was 3.0m wide on three sides and 8.4m wide on the outlet side.The gallery had removable gratings as cover in order to facilitate maintenance. Capacity of the reservoirwas proposed to be 40million gallons. The reservoir is divided into four compartments with baffle walls in each one for water circulation. Roof of the reservoir is kept at 300mm above ground level. There are two levels of car park on top of the reservoir. Top of the reservoir roof is at +14.35. Bottom varies from - 6.68 to -7.08. Lowest water table is at +6.00. Concrete structure of the reservoir was designed by a local consultant. The Navayuga Engineering Company was entrusted with the construction. Please see Figs 1 and 2."

Jan 1, 2017

By Mark S. Greenleaf, Alec D. Smith, Mary Vittoria-Bertrand, Heather B. Scranton, Jean Louis Z. Locsin

"Rhode Island’s new $163.7 million, 2,265 ft (690 m) long, four-lane Sakonnet River Bridge sits just south of the existing bridge in Portsmouth/Tiverton. The bridge, a critical transportation system link between Massachusetts and Rhode Island, has a steel I-girder main span and concrete New England Bulb Tee approach spans. The foundation work was done between October 2009 and July 2010, and the bridge was completed in February 2014.Foundation design and construction challenges make the project noteworthy. There were thick layers of silty glacial soils with bedrock as deep as 400 ft (122 m) below the waterline, coupled with high foundation capacity demands at the river piers in 50 ft (15 m) of water. The Sakonnet was one of the first major bridge projects in the country to incorporate AASHTO Load and Resistance Factor Design (LRFD) guidelines for foundation design and construction. Because of these and other challenges, the engineers conducted two design-phase load test programs on several foundation elements. These programs were successful and allowed the engineers to adjust the final foundation design prior to the start of construction. During construction, the contractors drove thirty 6 ft (1.8 m) diameter steel pipe piles, each with a novel recessed steel plate insert, to depths of 130 to 200 ft (40 to 61 m) at the three river piers. The insert provided increased resistance of the steel pipe piles and saved about $9 million. Also, 457 14x117 en bearing or friction H-section piles were driven to between 50 and 190 ft (15 to 58 m) at five land piers. All piles were driven relatively close to the existing bridge, which remained in service during construction, due to the project team’s precautionary use of instrumentation and the installation of a jacking system.Area GeologyThe Sakonnet River is up to 60 ft (18 m) deep along the bridge alignment and is underlain by a deep bedrock valley. The bedrock valley is buried by at least 350 ft (107 m) of soil, which includes a complex sequence of interbedded glacial soils (glacial till, glaciolacustrine deposits and glaciofluvial deposits), overlain by geologically recent estuarine deposits. The soils having the greatest impact on the foundation resistance are the glaciolacustrine (fine sandy silt or silt) and glaciofluvial (silty sand with gravel, cobbles, and occasional boulders less than about 2.5 ft [0.8 m] in size). The soil overburden decreases toward the east and west banks of the river, as the bedrock surface rises."

Jan 1, 2015

By John A. Egan, Nathaniel Wagner, Micaela Largent, Jonathan P. Stewart, Debra Murphy, Jeremy Butkovich

The Millennium Tower is a 58-story reinforced concrete building that was constructed in San Francisco, California between 2005 and 2009. The Tower is founded on an embedded pile supported mat with pile tips bearing in dense marine deposits that overlie an over-consolidated marine clay layer known locally as Old Bay Clay. This clay layer experienced stress increases from Tower self-weight and from multiple episodes of de-watering between 2006 and 2018 at the Tower site and neighboring sites. Settlements of the Tower foundation have been measured since 2006 and lateral deflections of the Tower have been inferred and measured since 2009. Available information on this case history include geotechnical site conditions and data from a monitoring program that tracked foundation settlements, Tower tilt, groundwater levels at the Tower site, and ground inclinations over time. This presentation will discuss the ground deformation mechanisms that caused the observed movements, the degree to which the movements can be predicted, and lessons from this case history for the design of deep foundations for tall buildings in San Francisco and geologically similar regions.

Sep 8, 2021

By Dharmil S. Patel, Zoyav S. Benyaminov, Cassandra A. Wetzel

Rehabilitation of the Henry Hudson Bridge is nearing completion, connecting Spuyten Duyvil in the Bronx to Inwood Hill in Manhattan, New York. Constructed in 1936, the Henry Hudson Bridge spans 840 feet over the Hudson River. Challenging geotechnical aspects of this Project required a team of innovators to overcome. Rehabilitation of the existing bridge involved the replacement of sixteen bent pedestal substructures, two abutment pilasters and installation of new deep foundations at the skewbacks. However, the Bridge, roadways, adjacent Metro-North Railroad (MNR) structures and New York City (NYC) Parks land were to remain open to the public for use, with minimal disturbance. In addition to physical constraints, geologic site conditions varied widely across both sides of the River, with varying bedrock quality and depth, greatly impacting the proposed design and construction. Extensive analysis of bedrock conditions was conducted to locate areas of potential wedge failure. The implementation of anchors was used to reinforce rock stability where pedestals and pilasters were replaced. This paper describes several challenging technical and natural aspects overcome in the rehabilitation of the Henry Hudson bridge foundations, including varying geologic site conditions, access restrictions, construction limitations, project specifications and design requirements.

Sep 8, 2021

By Roy A. Imbsen

Following the 1989 Loma Prieta earthquake, California Department of Transportation (Caltrans) expedited an effort to evaluate and retrofit important state-owned toll bridges to en­hance performance of the state's transportation systems during and after major (credible) earthquake events. Imbsen and Associates, Inc. (IAI) along with their sub-consultants, were awarded a contract to conduct seismic evaluation and to develop retrofit design for Benicia-Martinez Toll structure, to meet a "Serviceable" performance requirement after the event of a "Safety Evaluation Earthquake." This paper describes the design and construction specifications for the deep foundations supporting the main spans of the Benicia-Martinez Bridge. Benicia-Martinez Toll Structure (George Miller Bridge), a high-level deck-type welded truss bridge with welded girder approach spans, carries Interstate Route I-680 over the easterly end of Carquinez Strait near San Francisco, CA. The nearly 5000 ft long main truss structure consists of ten spans, ranging from 330' to 528' in length, supported on cellular reinforced con­crete pier structures. Foundation systems across the waterway, consist of cellular reinforced concrete footings, supported by groups of 6' diameter, concrete filled, steel caissons, resting on 5' deep rock sockets, at depths of 50' to 150' below the water level. Seismic evaluation of the existing foundation systems accounted for spatially varying ground motion along the length of the structure, variability of foundation material strength (i.e. at bed-rock), variation and effects of scour depth on the performance of the foundations, and dy­namic soil-structure interaction. Performance of caissons beyond their elastic strength, as well as their effects on the behavior of the foundations and substructures were evaluated and considered in establishing foundation vulnerabilities. Several retrofit strategies were considered leading to a final retrofit strategy to strengthen end connections of existing caissons, as well addition of new caissons to provide adequate lateral force resistance for the foundations. Final design package includes specifications as well as construction methods and requirements for existing and new caissons, under traffic, and pile load testing procedures for design loads of up to 12500 kips per caisson.

Jan 1, 1998

By Mohammad Nasim

Vertical expansion of existing structures frequently requires foundation retrofitting to enhance the capacity of existing foundations for supporting additional loads. Owing to their small diameter, a variety of suitable drilling methods available for installation, and smaller installation equipment capable of operating under limited headroom conditions, micropiles are often preferred for foundation retrofitting. This paper presents a case history demonstrating application of micropiles to underpin the existing foundation of the Washington D.C. Children?s National Medical Center (CNMC) for its future expansion. Located at 111 Michigan Avenue in northwest Washington, DC, portions of the hospital currently extend five stories above grade and three levels below-grade as parking garages. The hospital intends to expand the surgical wing up to the current build out (five stories) above the remaining portion of the existing parking garage. The original foundations consist of 80-ton Raymond Step-Tapered piles. New loading on the foundations required each Raymond pile to be capable of supporting 150 tons. Results from quick load tests on existing piles indicated that two entire column lines (Column Line A and B) would experience loads beyond their capacity, requiring enhancement of the existing foundation at these locations. The design and construction of the foundation upgrading work was particularly challenging due to various project constraints related to a high groundwater table, micropile installation under limited head room, and ensuring that the parking garage remained fully operational for the entire duration of construction. The paper presents the challenges faced during testing of existing foundations amid a high groundwater table, design developments of underpinning options to support the additional column loads, difficulties and challenges encountered during installation of the micropiles and construction of the micropile pilecaps, and value engineering options developed during various phases of the project. Understanding that micropiles are often a preferred option for foundation retrofitting, the case history is expected to provide a baseline design approach and innovative solutions to typical challenges faced during construction, thereby reducing potential cost overruns during design development and construction of similar future projects.

Jan 1, 2008

By Shields H. Arup

The paper describes the innovative foundation reuse and strengthening works for two buildings in Central London. A 1950s building on piled foundations (65 Whitfield St) and a 1930s building (67-69 Whitfield St) on 3m deep pad foundations were both extended upwards by two new stories. The Client for the project is Derwent London, with Make as their architect, Main Contractor Multiplex and Engineer Arup. Little was known about the foundations of either building at the start of the scheme. Extensive investigations of the existing foundations and ground conditions were carried out in both buildings. At 65 Whitfield St, investigations identified piled foundations, but found that pile lengths were short and variable. As a result, strengthening works solutions were adopted whereby the increase in column load was shed into new mini piles constructed around the existing pile caps. At 67-69 Whitfield St, deep pits were used to investigate the foundations and reuse was justified based on understanding of the pad dimensions, concrete strength, and strength and stiffness of the underlying geology. For both buildings the residual risk was closed out through monitoring during construction. The combined reuse of the structural frame and foundations of both buildings facilitated a sustainable solution, breathing a new lease of life into outdated buildings.

May 1, 2022

By Andy Boeckmann

Engineers and owners widely recognize the benefits of foundation reuse - cost savings, reduced construction schedules and reduced environmental impacts, among others. Yet for many projects with existing foundations identified as reusable, reuse is an idea that is discussed at length before cold feet prevail. To address this disconnect, Deep Foundations Institute (DFI) formed the Foundation Reuse Task Force in 2021, which intends to promote reuse, leveraging experience among DFI members and collaborating across pertinent committees. Indeed, the task force includes about 40 members drawn from the Subsurface Characterization for Deep Foundations, Sustainability and Testing and Evaluation committees. One of the first orders of business for the task force was to create a database of successful reuse projects, developing short summary documents highlighting the database projects and recruiting reuse-focused presentations for the ITS Money program. Solid progress has been made on each front: the case history database includes 12 cases so far; the first three summary documents were recently published to DFI's website and foundation reuse projects have been well represented among the past year's ITS Money program. The reuse case history summary documents are available at www.dfi.org/foundation-reuse- case-histories; each of the three is also discussed below. The summary documents demonstrate the feasibility and benefits of foundation reuse. The documents are therefore a useful tool for foundation engineers to share with owners, structural engineers and anyone else who may be hesitant to pursue foundation reuse. The task force continues to welcome new members and anyone interested in joining can contact Andy Boeckmann. The task force is also eager to highlight additional reuse success stories. Anyone with case history information to share is also encouraged to contact Boeckmann.

Jul 1, 2022

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 Sushant Upadhyaya, Deniz Karadeniz

As part of the widening of I-64 in Williamsburg, Virginia, an extensive subsurface exploration program consisting of Standard Penetration Tests (SPT), Cone Penetration Tests (CPT), Dilatometer Tests (DMT), and Vane Shear Test was performed. In addition to these in-situ tests, an extensive laboratory testing program was completed including Consolidated-Undrained Triaxial, Unconsolidated-Undrained Triaxial, Direct Shear, and consolidation tests. The strength and the compressibility properties are deemed conservative for Yorktown and St. Mary’s Formations when evaluated based on the current topography, the existing overburden pressure and SPT values. SPT exhibited low blow counts especially within Yorktown Formation due to the increased excess pore water pressures resulting in a localized liquefaction at the tip of the split spoon sampler corresponding to remolded or fully softened strength of the soil. Therefore, the applicability of the SPT correlated soil parameters somewhat leads to conservative designs with deeper piles to achieve a desired structural load demand. Generally, the in-situ estimated soil design parameters are found to be comparable with the laboratory test results corresponding to long-term resistance gain with time. It is of practical importance to employ realistic soil design parameters for design applications such as pile foundations to provide cost and schedule savings. This paper presents a discussion on the soil strength estimates and variability from in-situ and laboratory tests for realistic strength characterization of Coastal Plain deposits.

"The Morris Island Lighthouse (MIL) is located between the jetties leading to the Charleston Harbor and Folly Beach, S.C. The present structure is the third lighthouse to occupy this location. The first navigational aid was erected in 1673, and consisted of a raised pan filled with pitch, which was set afire at night to guide early ships. The next structure was built in 1767, and constituted the first real lighthouse, standing 42 ft (12.8 m) in height. In 1838, a second lighthouse was built on the site, and it measured 102 ft (31 m) in height and featured a revolving light. This structure lasted until 1862 when Confederate troops, during the Civil War, destroyed it to deny its use to Union troops.Navigators steered these waters without a lighthouse for nearly a decade until 1876, when the current structure was built under the direction of the U.S. Army Corps of Engineers (USACE). In 1886, the Charleston area suffered a M7.6 earthquake. Significant damage was caused throughout much of the area, including a slight “list” of the lighthouse to the northeast. As a result, the cast of the beacon was reduced from 18 mi (29 km) to about 6 mi (9.7 km), causing much distress to navigators until the beacon platform was releveled and remains at this list to the present day.Conditions for ConcernThe current lighthouse was originally constructed about 1,200 ft (366 m) from the shoreline. Over the years, USACE has undertaken several programs to meet the increased shipping and navigation demands in the Charleston Harbor. Around the turn of the last century, two jetties were constructed, which drastically changed the approach direction for ships entering the harbor. In subsequent years, the harbor began to experience accelerated siltation."

Jan 1, 2017

By E. Watkins, M. B. Daza

Although there have been great advances regarding the understanding of mine fires in underground mines in the last century, fires remain high risk incidents. During fire scenarios, many crucial decisions and actions can be made that greatly influence the outcomes of these scenarios. Underground worker decisions are mainly based on training and experience, which in some cases can be complemented with previous analysis of fire effects. In order to review the guidelines that should be taken into account for this kind of examination, a numerical analysis of effects produced by a shuttle car fire under five different ventilation conditions was carried out. The analysis provides some insightful recommendations for firefighting personnel such as time for direct attack and best attack position for first responders and fire brigade groups. Also, the most critical parameters for each scenario were determined. Finally, all results were systematically organized and a first approximation of a fire classification based on the tenability limits was provided for first responder and fire brigade groups. The methodology used in this study for the fire classification could allow for the most appropriate decisions by firefighting personnel increasing the probability to put fires out without compromising their health and safety. INTRODUCTION While there have been great advances regarding the causes of mine fires in underground mines in the last century “small fires have occurred and always will occur in underground mines” (Conti, Chasko, Wiehagen, & Lazzara, 2005). The response time and decisions made during an underground mine fire are critical elements that have direct influence on the event outcome. Mine fires can grow in size quickly causing catastrophic consequences, thus rapid and suitable response actions can result in the difference between an minor emergency situation and a disaster. Upon the confirmation of a fire, a decision must be made regarding whether to fight the fire or evacuate the mine. Even though all underground coal mines possess emergency response plans and firefighting personnel are highly trained, decisions can be complemented with previous numerical analyses. Such analyses could contribute with the knowledge of potential fire effects and consequently with fire preparedness in the mine. Preparedness in underground mines is an important element to reduce the probability of the negative consequences of a mine fire. The time elapsed between the detection of the fire and response in the early stage is a serious component since small fires can produce larger and more serious consequences. If a mine fire cannot be put out within the short time after discovery, the chance of getting the system back in balanced or the success of safely controlling and extinguishing a mine fire is reduced (Conti et al., 2005, Conti, Chasko, Wiehagen, & Lazzara, 2000, Trevits, Yuan, Teacoach, Valoski, & Urosek, 2009, Brake, 2013). As confirmed by Conti and others, if a mine fire cannot be controlled by direct firefighting methods the probability of extinguishing the fire, without sealing is greatly reduced (Conti et al., 2005). However, response actions such as direct extinguishment must be carried out without compromising the health and safety of the firefighting personnel (Kim, Lönnermark, & Ingason, 2010).

Jan 1, 2019

By Per Eriksson

For light buildings on clay, foundations on L/C-columns is in many cases a competitive alternative to piles when the thickness of the clay is moderate (<20 m). The method is applicable for the above mentioned depth when the clay is normally consolidated, and for thicker deposits when the clay is overconsolidated at depth. This case study concerns a shopping mall in Nordby, Sweden, founded on L/C-columns (5-15 m in length) and generally spaced 1.45-2.0 m (spacing 0.7 m was used below pillars). The base slab was built as a raft foundation, using fibre reinforced concrete.

Jan 1, 2000

By K. Viking

This article deals with some of the civil engineering related problems to be encountered when offshore wind energy projects transform from prototype offshore wind energy converter farms, developed and installed during the 1990&apos;s, to commercial farms that&apos;s currently planned to be built. The offshore wind energy converter (OWEC) installations encounter a wide range of problems, only partial of these are geotechnical. In Europe both onshore and offshore wind farms have, from a historical point of view, usually been founded by using the monopole technique, installed with traditional impact hammers, or by using gravitational foundations. However, the rapid development of bigger turbines and larger wind farms, together with increasing considerations of fatigue aspects, has lead to financial benefits of developing and exploring other foundation techniques. This paper reviews some Scandinavian experiences regarding critical components of the design phase in relation to connecting the superstructure to the ground, and some of the main considerations of how the loads applied to the structure are transferred to the surrounding soil. Keywords: Offshore Wind Turbines, Wind Farms, Foundation, Pile, Gravity Structures

Jan 1, 2005

By K. Viking

This article deals with some of the civil engineering related problems to be encountered when offshore wind energy projects transform from prototype offshore wind energy converter farms, developed and installed during the 1990?s, to commercial farms that?s currently planned to be built. The offshore wind energy converter (OWEC) installations encounter a wide range of problems, only partial of these are geotechnical. In Europe both onshore and offshore wind farms have, from a historical point of view, usually been founded by using the monopole technique, installed with traditional impact hammers, or by using gravitational foundations. However, the rapid development of bigger turbines and larger wind farms, together with increasing considerations of fatigue aspects, has lead to financial benefits of developing and exploring other foundation techniques. This paper reviews some Scandinavian experiences regarding critical components of the design phase in relation to connecting the superstructure to the ground, and some of the main considerations of how the loads applied to the structure are transferred to the surrounding soil.

Jan 1, 2013

By John F. Spence

Ever since opening, the M25 motorway to the west of London has carried a rapidly increasing volume of traffic. The section of M25 between the junctions with the M3 and M4 motorways, which is in the near vicinity of Heathrow airport, is the most heavily trafficked section. Piling and ground treatment was required for motorway widening works over this route, which is 7 miles long. The foundation works were undertaken next to the live motorway and beneath the flightpath for aircraft landing and taking off at the airport. The paper describes the foundation construction techniques used, and the how the methods were affected by the live motorway and the height restrictions imposed by the airport. A unique method of piled retaining wall construction is also described.

Jan 1, 2007

By Clyde N. Baker

Foundations for the Sohio Corporate Headquarters in downtown Cleveland have column loads of 11,400 kips, which increase to 15,000 kips with wind loading. An extensive exploratory program was conducted and comprehensive studies made to select the economically dependable support for the 46-story structure. A test on bond or socket friction for the caissons has usable values.

Jan 1, 1984