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By Timothy Nelson, Simon Burnworth

"The 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 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.The site was perfect; located one block east of bustling downtown Berkeley and its rapid transit station, and directly across the street from the western entrance to the UC Berkeley campus. Thousands of pedestrians pass by the site on a daily basis, thus granting BAMPFA the opportunity to reshape the corner of Center and Oxford Streets with a building that would not only welcome visitors to campus, but also serve as a creative hub for both the City of Berkeley and the UC Berkeley institution itself 1.The original museum plans, drawn up in the mid-2000s, called for complete demolition of the existing abandoned facility and replacement with a visually stunning structure designed by renowned Japanese architect Toyo Ito. Even at this point, the shoring and means and methods requirements of the project were identified as a challenging component, incorporating a shored excavation bounded on three sides by busy city streets and a fourth side by an operating bank and occupied apartment building. Furthermore, a sequenced demolition would be required for the printing press facility’s three-story Administration Building (also known as the Admin Block), one-story printing press warehouse (also known as the Press Building), and an adjacent parking structure. Degenkolb Engineers was retained at that time as the shoring engineer to design the shoring to facilitate this work."

Jan 1, 2016

By Rob van Dorp

"AbstractThe Monitoring & Instrumentation Committee (MIC) of DFI Europe has the objective to support DFI members in concern of risk management of geotechnical matters, where monitoring and instrumentation have added value.Work of the CommitteeA study by the committee showed that there are already several existing (national) guidelines. They all have their strengths and limitations and their focus may vary a little per country due to local regulations and typical local building activities, but the main question remains what added value another new guideline would have. More likely it would add to the confusion instead of providing overview.Companies with larger experience in geotechnical monitoring (often larger consultancy firm, contractors or clients) are already quite familiar with its benefits do not really need a new guideline in how to design and effectively apply sophisticated geotechnical monitoring systems for special projects.Therefore the aim of the MIC is to focus a little more towards smaller organizations - that are less familiar with monitoring and instrumentation - and the more ‘regular’ type of project that they are mainly involved in. The MIC wants to create a tool which helps them to create risk awareness, to understand the benefits of geotechnical monitoring and to provide them information about how and where to find the right partners and equipment to setup and apply appropriate monitoring systems for their projects.Monitoring and instrumentation benefits are for example:• Risk control during construction stage;• Costs reduction in design and construction (taken limitation of geotechnical aspects into account).• Prevent of unnecessary delays in construction work• Increasing general awareness of geotechnical risks and possibilities of monitoring.The cost of monitoring compared to the cost of failure and/or the savings that can be achieved play a role in the work of the committee. DFI members benefit from the shared knowledge by the MIC on monitoring and instrumentation within their process of risk management."

Jan 1, 2014

By D. M. Holloway

As a part of the 1-15 Reconstruction Project, static and dynamic (high-strain) testing methods formed the basis to estimate long-term axial capacities, and to assess the magnitudes of bearing capacity gains (setup) from the end of installation to the time of static/dynamic tests weeks later. This paper summarizes the results of nine full scale pile load tests to failure in compression, and how the designers used these data to finalize pile selection and penetration criteria bridge-by-bridge in the final design stages. Soil conditions along the project alignment ranged from deep, lightly over-consolidated Lake Bonneville clays interbedded with granular strata of varying consistency, to sites dominated by dense alluvial deposits of cohesionless soils well above the water table. The test sites were selected to bracket the conditions that are expected. Twelve-, 16-, and 24-inch-OD pipe piles are to be used to support the new bridges. The team plans to impact-drive all piles closed-end to final penetrations. The test piles varied from 35-ft-long pipes driven to refusal in the shallow dense sands at some sites, to 115-ft-long pipes stopping at 3 blows per foot in predominantly cohesive deposits. The capacities gained with time proved to be reasonably predictable, and significant setup was noted both in the cohesive and cohesionless strata. The test program objectives included providing the means to estimate long-term capacities from short-term (24- to 48-hour) restrikes following installation of foundation piles during production driving operations.

Jan 1, 1998

By Mike Muchard

STATNAMIC load testing augmented with embedded instrumentation has been successfully used to obtain structural and geotechnical design information on large diameter spun cast concrete cylinder piles on many large marine construction projects. The paper focuses on one particularly interesting large marine project involving a new bridge to St. George Island, Florida where instrumentation and STATNAMIC load testing was used in conjunction with static load testing on high capacity piles. The information presented includes embedded instrumentation measurements taken during pile fabrication (post-tensioning), during pile driving, during static load testing, and STATNAMIC load testing. As much of this data is the first of its kind on concrete cylinder piles, it is exciting to present the foundation industry with this additional insight as to the behavior of this pile type and the accuracy of the methods used to test them.

Jan 1, 2013

By Willie M. NeSmith

Cast-in-place piling are a staple of the deep foundation industry, and are used (in various forms) worldwide. In assessing the application of cast-in-place piles, it is of value to reflect on the development of the various systems, in order to understand how the current processes and equipment came to be. This paper traces the evolution of the cast-in-place industry. Emphasis is on developments in the United States; however, since there has been a substantial fusion of US and European processes, notable European developments are also discussed.

Jan 1, 2006

By N. Som

The pile capacity in cohesive and granular soils depends on a number of parameters. The values of these parameters as recommended by Indian Standard Code of Practice vary over wide ranges. A designer often finds it difficult to select appropriate values of these parameters for realistic estimate of a pile capacity. The present paper makes a critical review of the values of the parameters given in Indian Standard Code of Practice and suggests a realistic approach to selecting them in the light of recent research.

Jan 1, 1996

By Alexander Filotti, Richard Kalson

"In the last decade, the construction industry has witnessed significant changes in the project delivery systems and contractual relationships between the general contractors (GC) and Deep Foundation Specialty Contractors. The Deep Foundation industry, especially including industry specialty subcontractors, have experienced a significant increase in requests that project risks be transferred through contract documents to subcontractors and suppliers with a decrease in margins for the industry. GCs regularly revise their form subcontracts to take into account recent experiences/contractual trends and newly issued judicial precedent, an exercise that is less frequently undertaken by subcontractors and suppliers. These contradictory trends are at the base of the ethical analysis of subcontracts that comprises the subject matter of this paper. Using contracts as a risk management tool in order to mitigate the general contractor’s risks in the context of dynamic changes in the legislative environment will also be addressed. Furthermore, another possibility for risk mitigation for the industry is to actively promote the introduction of the latest technical developments into the contract documents.CONTRACTS’ ETHICSFor thousands of years, ethics have been a constant presence in our lives and have been debated by different branches of philosophy. In modern times, ethics in business started to be an imperative for the success of a globalized economy.“Ethics are standards by which one should act based on values. Values are code beliefs such as duty, honor, and integrity that motivate attitudes and actions.” (Rumbaugh 2004). Some of these values and actions have been carved in legislation in general and in business legislation in particular. More and more, unethical business practices (e.g., corruption) are identified as the root cause of poverty, underdevelopment, and war around the world. In the context of contract ethics, three aspects are of interest:•,Ethics of contract construction•,Ethics of contracting processes•,Ethics of risk allocation in contracts"

Jan 1, 2016

Jan 1, 1997

This specification, along with the drawings, encompasses all designs, materials, products, accessories, tools, equipment, services, transportation, labor and supervision, installation techniques, and testing procedures required for the installation of soil nail excavation support or earth retention systems. This is a Guide Specification designed to assist in the development of project specifications for soil nail excavation support and earth retention systems. This Model Specification is based on generally accepted industry standards but may require modification by the specification writer to accommodate unusual and/or unforeseen site and subsurface conditions and the particular circumstances of the project. Care must be taken to avoid internal inconsistencies. It contains language allowing for a Contractor-Designed Soil Nail Wall, which would be removed if the design is provided by the Owner (e.g. See Sections 1.2 and 4.1).

Jan 1, 2010

By Nikolas Schmitz

For today’s construction industry, large-diameter piles are common practice, as they are more competitive than drilling a larger number of smaller piles. More and more piles are installed by drilling rigs, replacing the installation by hammer, vibrators or caisson. Equipment capabilities and technics with rotary drill rigs are highly developed, but very costly and time-consuming when it comes to rock drilling, large diameters and deep foundations. Pile top drill rigs (PBA), based on reverse circulation drilling (RCD) technology, overcome these challenges and are an efficient solution for large diameter drilling (0.6 m to 8.0 m/19.7 ft to 26.3 ft) and drilling depths of up to 500 m (1,640 ft.)in various geological conditions onshore and offshore. The paper will explain benefits of RCD technology and prove this with figures from the Mumbai Trans Harbour Link project.

Nov 1, 2022

Jan 1, 2001

Jan 1, 2001

By R. J. Yan

There was a plant equipped with a 32000t Hydraulic Press to be built, under which a box foundation of 22.5m x 15m x 14.25m (depth) with a base slab of, varying thickness was proposed. The subgrade reactions, bending moments and settlements needed to be determined by means of in-situ model test. A model of the same materials as the prototype scaled to l/10 was embedded in-situ with simulated depth in the bedrock. A lot of data obtained from 39 bench marks, 32 elongation measuring points, 30 couples of electric resistance strain gauges and 24 pressure cells attached to the model foundation enables all the quantities required to be found out. Since it was put into operation, the settlements measured has reasonably agreed with the test results and the foundation has been in good condition.

Jan 1, 2010

Jan 1, 1990

By Heinrich Majewski, Rob Jameson

"Careful review of site conditions and constraints is essential to select the appropriate shoring system for each project. Key evaluation criteria include the geotechnical profile, groundwater and environmental conditions, adjacent buildings and utilities, schedule and any project specific access or other constraints. Typical earth retention schemes range from rock or soil nail walls, through conventional anchored pile and lagging walls to deep internally braced cut-off systems. The Owner’s design team will often develop the conceptual approach under their design studies, and this is refined with Contractor input through Design-Build or Design-Bid-Build procurement. In downtown San Francisco, underground construction must accommodate a unique combination of variable fill, soil, rock and groundwater conditions, potential for severe seismic loadings, and constrained sites within a dense urban environment. The quarter square mile of San Francisco’s Transbay and Rincon Hill districts has seen repeated cycles of development, destruction and re-building through earthquakes and the economy, and has been intensely redeveloped over the last decade. Over 50 acres of this land has been reclaimed from the Bay since the Gold Rush and within 3 city blocks the bedrock slopes from over 250 FT depth below the fills up to outcrops over 100 FT above sea level. A series of project examples from within this small area illustrate how varied shoring systems have accommodated the highly variable subsurface conditions while offering best value in terms of cost, schedule and appropriate protection of adjacent facilities.INTRODUCTIONA walk of 3 blocks from Rincon Hill on San Francisco’s Harrison Street, north through the Transbay area to Mission Street will traverse an urban zone which has been reinvented twice within its 150 year history in response to major seismic events. This small area highlights the range of subsurface conditions and urban environments which are encountered and accommodated in shoring schemes throughout the city. This route down the north side of Rincon Hill overlies a steep bedrock slope, outcropping over 100 FT above sea level at its south end and dropping to over 250 FT below sea level at Mission Street. A complex overburden soil profile, shaped by seismic activity and changing sea-levels has created layered soils ranging from soft estuary muds, dense sandy strata and deep clay layers, in turn topped with urban fill, frequently contaminated with debris from the Great 1906 earthquake. This route runs parallel to, and 350 yards inland of, the San Francisco shoreline resulting in groundwater elevation close to sea level with almost limitless recharge within granular layers. On the higher slopes of Rincon Hill, groundwater is typically observed flowing on top of and periodically within the fractured bedrock formation. The Transbay and Rincon areas were developed early in the Gold Rush era of San Francisco. After destruction in the 1906 earthquake and fire, they became a transit gateway into the city throughout the 20th Century. Demolition of the Embarcadero Freeway in response to earthquake damage and social pressure has opened this large area to redevelopment within the last 20 years, creating a new commercial and residential hub for the city. In its latest wave of building, planners are developing taller structures with deeper basements, in turn creating new construction challenges. Selection of shoring systems appropriate for these developments requires detailed evaluation. The process must address both the rapid spatial changes in subsurface conditions and the constraints surrounding, and specific to, each site in order to define shoring performance requirements. This paper presents an overview of the subsurface conditions and land use development of the Transbay and Rincon Hill areas, with examples of the shoring systems selected to meet site-specific conditions and requirements. The projects cited range from soil nail wall"

Jan 1, 2017

By Philip Derbyshire, Dale J. Scheffler

"Continuous Flight Auger (CFA) piling is a variation of Augered Cast-In-Place (ACIP) or augercast piling. In both cases a continuous auger with a hollow stem is used to drill a hole and a pile is formed by injection of cementitious material through the hollow stem as the auger is withdrawn. CFA differs from conventional American ACIP by the use of concrete rather than grout to form the pile, and by the type of equipment used to advance the auger into the ground and withdraw it. CFA installation uses a European style rig (i.e. fixed mast and rotary system) which can produce greater crowd and usually has a larger rotator or drill motor than the standard augercast setup. A standard augercast setup will consist of a lattice-boom crane and a set of leads to house the drill motor and auger. The auger size will range up to 24 inches (610mm). With CFA rigs larger diameter piles can be constructed, 24 to 36 in dia. (610mm to 915mm) are common and the technique has been applied with diameters up to 48-inch (1220mm). CFA makes use of sophisticated computer controlled monitoring systems, which have more recently been introduced for conventional ACIP piling. Developments in CFA have taken place over the last 25 years in Europe and particularly in the UK, but are relatively new in the USA. One application is in the construction of secant (overlapping) piled retaining walls. D.J. Scheffler Inc. recognized the potential of the CFA system following visits to the UK and has introduced its use into California for both secant piling and other applications.BACKGROUNDThe high price of real estate in many of the favored areas of California has increasingly led owners to want to build basements under their houses to increase the floor space available on a lot. Many of these areas are by the coast where the ground conditions are predominately granular and the water table is high. Conventional shoring and dewatering systems have often caused problems with adjoining properties. Clearly tangent walls are not suitable in these conditions because of leakage and loss of ground. The secant pile system, using CFA techniques, has proved very effective at overcoming the problems experienced by other methods. Other applications for CFA secant walls have included use for an emergency job on a highway following erosion caused by unusually heavy rainfall.METHODThe concept of secanting piles, whereby primary(female) piles are installed first and then secondary (male) piles are cut into the primary piles is not new. The method has been known for more than 30 years. Originally ‘Benoto’ grabbing rigs, developed in Japan, were used together with sectionalized double skinned casing and oscillators.This early method was slow, although very effective. More recently high torque rotary machines have been used. Contractors in the UK have increasingly used CFA techniques to further improve productivity of this type of piled wall. The improved capabilities of piling rigs available, as well as developments in concrete technology and instrumentation, have made this possible."

Jan 1, 2005

By Dr Karsten Galipp, Kai-Julian I. Hendler, Prof. Manuel G. Pinheiro, Dr Peter J. Bourne-Webb

With a share of approximately 11% of global greenhouse gas emissions, the construction industry contributes significantly towards climate change. This is why construction projects should not only be assessed on costs and technical solutions, but also on their carbon emissions. Life Cycle Assessment (LCA) is a tool which can quantify the environmental impacts of a construction project over its entire lifetime. The objective of this study was to determine the carbon footprint of three types of quay wall structures, namely sheet pile combi-walls, open piled decks and caissons using an LCA approach. Each of these quay walls were studied under the same boundary conditions, such as design life, ground conditions, dimensions, location and so on. The analysis showed that the sheet pile wall has the lowest carbon footprint whereas the open piled structure has the highest. Furthermore, it could be shown that the largest share of greenhouse gases (approximately 80%) is emitted during the production of construction materials. The transportation of materials and construction activities each contributed under 12% to total emissions. The sensitivity analysis showed that with innovative approaches, such as adapting the concrete mix design, the carbon footprint could be reduced by 26% to 40%.

May 1, 2022

By David H. Sanders, Ramin Motamed, Fahim M. Bhuiyan, Raj V. Siddharthan

Large-diameter drilled shafts (DS) are a critical part of a seismic-resistant system, and therefore it is important to be able to accurately model lateral resistance. To undertake the lateral load analysis of largediameter DS, a finite-difference p-y analysis program, NVShaft, is being developed at the University of Nevada Reno. Validation of the new program involved numerous p-y analyses using commercially available programs. Subsequent comparisons suggested the program's ability to yield reasonable predictions for typical diameter DS. Based on the I-15/US 95 load test program carried out in Las Vegas, NV, this study presents the evaluation of NVShaft in Nevada’s subsurface condition. Lateral load analyses of a 2 ft and an 8 ft diameter DS were attempted using NVShaft. The location of the applied lateral loads and the presence of cemented soil-layers were incorporated in the modeling. A good agreement between NVShaft prediction and the measured response was found for the 2 ft diameter DS. For the 8 ft diameter DS, a stiffer response was predicted. The inspections of the moment-curvature characteristics at different load levels suggested cracked response of the concrete due to prior axial load testing may be one of the reasons behind the deviation.

The intent of this manual is to provide guidelines for inspectors of drilled shaft construction otherwise referred to as drilled piers, caissons or bored piles. It should also be helpful to train beginning geotechnical engineers with limited first hand experience or for geotechnical engineers who are training inspectors. It is expected that the general guidelines and procedures described here will be supplemented by local geotechnical engineers working in a particular region based on local practice and experience. Since drilled shaft construction procedures vary widely based on local geology and size of project, an all-inclusive manual is not considered practical. This manual focuses on traditional topside inspection for routine drilled shaft construction. Other inspection and evaluation methods that rely on electronic equipment are available, but these methods require extensive training and experience in the interpretation of results. These more sophisticated methods of drilled shaft inspection and evaluation are common in construction, but they are usually provided by specialty subconsultants. The subconsultant will typically submit a report for each shaft, which will be reviewed by the geotechnical engineer. Other manuals are available to describe the electronic methods of drilled shaft inspection.

Jan 1, 2004

By John C. Tosh, Peter M. Kandaris, Sheldon John

Geologic, geotechnical and hydrologic studies were performed for the design of 115 deep, large diameter drilled shaft reinforced concrete foundations (6 to 12 feet) to support tall steel monopoles for a new 13-mile long 230/69kV transmission line in southwestern Arizona. The subsurface conditions along the alignment posed a wide range of challenges for performing investigation and design studies. These conditions include saturated, loose granular flood plain deposits with generally low lateral capacity, potential ground loss up to 23 feet due to occasional river flow (scour and embankment loss), liquefaction impacts from nearby active fault seismicity that can generate magnitude 6.5-7.0 earthquakes, and unsaturated alluvial and eolian sand-dominated soils to full depth with low lateral capacity. All conditions will require significantly deeper than normal foundation embedment (depth ranging from 22 to 77 feet) and will present construction difficulty due to ground instability from groundwater and dry soil sloughing. A phased investigation was performed to accurately characterize the conditions for design and construction, and included performing a review of existing data, detailed field geologic reconnaissance, a limited number of standard exploratory borings (limited access), seismic cone penetrometer soundings (SCPT) in saturated soils to better understand liquefaction and strength loss potential, and hydrologic analyses to estimate scour/ground loss potential. This paper describes the site conditions, presents details on the investigation team’s approach, documents findings in relation to deep foundation analysis and design, and discusses recommendations for foundation construction to help in reducing risk.

Sep 8, 2021