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By Basem Sh. Hazzan

In the last four decades significant effort has been devoted to designing piles in expansive clay soils. Nevertheless, only a scant effort has been devoted to the elimination of heave forces acting on the upper part of lightly loaded piles. For this purpose, an investigation site was established in Karmiel in Northern Israel. On this site sixteen unloaded cast-in-situ piles, both uncoated and coated, were installed in a moderately expansive clay soil in the end of summer 1996. The piles were executed to different depths ranging between 2m and 7m and were observed over a period of 27 months. Another nine unloaded cast-in-situ bored piles were installed at the end of summer 1998 for carrying out pullout tests. These piles were embedded two meters from the ground surface. Results obtained from observations and from full-scale static pull out tests showed that separating the piles from the surrounding clay in the active zone by a twin walled sleeve eliminated the heave forces significantly. The scope of the work is, determining of the elimination degree of the heave forces due to the provision of the above sleeve.

Jan 1, 1999

By J. J. Beresford

The primary function of a support slurry is to provide stability during excavation. Today foundation structures can be designed around the additional friction afforded by the absence of the filter cake attributable to the use of polymeric fluids as support slurries. These fluids use pseudoplastic fluid viscosity to advantage over the fragile thixotropic gel structures of bentonite. Many of today's polymeric fluids are environmentally acceptable for disposal directly to municipal sewers.

Jan 1, 1989

By Helmut Hass, Marco Ziller

"Abstract: 1 Sophia Spoortunnel Marco Ziller, Trevi S.p.A.:For the construction of 14 cross passages connecting the twin tunnels of the Sophiaspoortunnel the Artificial Ground Freezing technique was applied as temporary soil improvement. AGF by Brine and Liquid Nitrogen was implemented. Automatic data acquisition and recording systems were installed to monitor the variation of the temperatures in the soil during the freezing intervention in order to control the behaviour and the efficacy of the treatment.IntroductionThe Sophia rail tunnel is a bored tunnel with a length of 4.24 km, comprising two separate parallel tubes with an outside diameter of 9.45 m. The twin tunnels were excavated by a TBM equipped with hydroshield. Seven service shafts, approximately 30 m deep, were constructed in between the tunnels. From each shaft two cross passages were constructed connecting the shaft with both tubes, for a total of 14 cross passages.The Artificial Ground Freezing technique utilizing both the Brine and Liquid Nitrogen methods was used for temporary waterproofing and soil support to allow the excavation of the cross passages. The natural soil to be frozen was consisting in loose sand and clay under a hydrostatic pressure up to 250 kPa.For the measurement of the ground temperature. Automatic data acquisition and recording systems were installed to monitor the variation of the temperatures in the soil and at the contact with the tunnel lining. Furthermore, a comprehensive computerized system of sensors and cryogenic valves was designed and implemented in order to manage the whole Nitrogen process.Soil Main CharacteristicsThe soil stratigraphy is generally consisting in Clay (Holocene) from ground level to -15 m depth, followed by Pleistocenic Sand, from -15 to -25 m, and Clay below -25 m."

Jan 1, 2014

By Derek J. Lennon

Ground conditions in central Glasgow generally comprise loose granular deposits overlying stiffer soils. CFA piling would normally be preferred for urban sites in these ground conditions, but flighting of the superficial deposits has on occasions resulted in building damage. Over the last five years rotary bored piling with vinyl polymer support fluid has proved to be an economic alternative to bentonite slurry. Two case histories in central Glasgow are described in this paper, one for piles founding in granular soils and one for piles founding into bedrock. A comparison is made between the methods required for disposal of the liquid waste from bentonite and vinyl polymer slurries.

Jan 1, 2006

By Alun J. Davies

This paper describes a design-build project for the construction of a tanker wharf for 150,000 dwt vessels. The tankers deliver oil from offshore oil fields to a Transshipment terminal on the south coast of Newfoundland. The project described is an expansion to a previously constructed facility, adding an additional berth. The first berth was designed conventionally as concrete structures supported on groups of independent, single piles. The second berth was awarded to Peter Kiewit Sons' Co. Ltd. based on an alternate design which utilized a "jacket" concept whereby prefabricated steel frames are placed on the seabed and serve as permanent templates and also give lateral support to the piles, thereby increasing their load capacity. This led to economies and time savings. Discussed herein is the design process and the field installation, covering the jackets, driven pipe piles, and the rock anchors.

Jan 1, 2000

By Darrell Wilder

When designing excavation support systems in urban environments, it is often necessary to consider the effect of vertical surcharge loads from adjacent structures. Several methods are used in practice to establish the horizontal surcharge-induce pressure on the excavation support. According to the experience of the authors, these methods often seem to overestimate the effect of the surcharge and may have significant impact on the construction costs. This paper explores several of these procedures and provides a discussion as to the reasons for the differences in surcharge effect predictions between different procedures. It also provides practical recommendations for designers dealing with excavation support design.

Jan 1, 2006

By George K. Burke

Underpinning of a structure has been traditionally expensive, time consuming, and, in many cases, caused as much settlement to the existing structure as it was trying to prevent. As underpinning is normally one of the initial tasks and on the critical path on a construction project, there is immense pressure on the subcontractor to speed up his operation so the new structure can proceed; this can cause an adversarial relationship to develop between the owner, engineers, general contractor and subcontractor. Since its introduction to the North American market in the late 1980's, Jet Grouting has not solved all these problems, but where utilized, has shown economical benefits, a faster and safer installation, and a minimal movement of the structures being underpinned. A history of the development of jet grouting is presented; a comparison of this technique versus other grouting methods, a description of the jet grouting system with emphasis on the triple rod systems; case histories of jet grouting used for underpinning and conclusions and references are included to follow the program's themes of: - Recognizing Solutions to Today's Problems - Defining Tomorrows Challenges - Putting America on a Solid Foundation

Jan 1, 1991

By Carole L. B. Mitchell

The South 180th Street Grade Separation underpass in Tukwila and Renton, Washington, USA, permits vehicular traffic to pass beneath Burlington Northern Santa Fe and Union Pacific railroad tracks. The railroad tracks were temporarily relocated onto a shoofly crossing while the permanent bridges were constructed. The maximum underpass depth is approximately 25 feet (7.6 meters [m]). The majority of the sidewalls are supported using alternating reinforced and unreinforced secant pile walls. Temporary and permanent struts brace the top of the excavation. Because the groundwater is about 15 feet (4.6 m) above the base of the excavation and the subsurface materials are loose to medium dense fill, alluvium, and soft flood plain organics, the base of the excavation was strengthened and sealed using wet cement deep soil mixing (CDSM) methods. During construction, CDSM-treated ground temporarily acted as part of the railroad shoofly shoring while the remainder of the underpass was excavated on either side of active railroad tracks. The combination of secant pile sidewalls and CDSM bottom seal allowed for easy excavation, even during wet conditions. Using a 35-foot-thick (maximum) (10.7-m) CDSM layer both to act as a bottom seal and to resist uplift pressures is a unique, dual-purpose application of CDSM technology in the United States.

Jan 1, 2004

There are many ways to classify structural slurry wall elements, but the DFI committee chooses to limit these descriptions to three functional requirements, namely: design function, plan configuration and type of panel reinforcement. (See Figure 1 in Part IV for panel classification). Slurry walls can function as: 1. Curvilinear or linear elements for temporary and/or permanent structures to resist lateral forces transferred from the ground, water, earthquakes and various surcharge loads. 2. Load bearing elements in various plan shapes to resist vertical forces. 3. Combination Elements to resist combined forces under conditions 1 and/or 2. For example, elliptical shafts with various openings for tunnels and conduits have been commonly used for deep excavations.

Jan 1, 2005

By Leo Panian, Ryan Nagle, Priyanshu Singh, Gina Carlson, Wayne Magnusen

"This case study presents the design and construction of an integrated foundation and ground improvement solution utilizing deep soil mixing (DSM) and micropiles. 270 Brannan is a midrise office building in San Francisco that straddles the historic shoreline that was reclaimed in the 19th century. Subsurface conditions include shallow bedrock inland of the historic shoreline, and steeply dipping bedrock overlain by 60 feet of compressible deposits and liquefiable fill on the bay side. Project challenges included mitigating the liquefaction and lateral spreading hazards, addressing settlement concerns in the fill and the bay deposits, developing a cost-effective foundation support solution, assuring satisfactory seismic performance, and addressing construction restrictions with existing adjacent structures.DSM combined with micropiles was identified as the most cost-effective solution for the ground conditions. The DSM panels act both as a liquefaction mitigation mechanism and a foundation support system. Resistance to seismic overturning is provided by uplift-resisting micropiles. The DSM-micropile solution allows the use of efficient conventional spread footing foundations, integrating isolated micropile groups to anchor the shear walls. Successful installation of the system relied on a program of field testing to validate the design and conformance with the design criteria.INTRODUCTIONThe regular grid of surface streets within San Francisco’s South of Market (SOMA) district provides little evidence of the geotechnical complexities that lie below. In the late 1800s, sand dunes, bedrock hills, cliffs, marshes, and mud flats were flattened and filled, concealing their locations and characteristics. The 1906 San Francisco earthquake and fire leveled many buildings in SOMA; new buildings were built after 1906 – often on top of rubble and debris from the structures that came before. Locally, the combination of natural geology and historical interventions can produce complex subsurface conditions that vary dramatically over short distances. This is particularly true at locations where tidal mudflats once met bedrock hills at the shore of San Francisco Bay.This case study describes an integrated foundation and ground improvement system implemented for a multistory “Class A” office building at a complex SOMA urban infill site. The system utilizes cement deep soil mixing (DSM) in combination with spread footings and micropiles to address a range of design and construction issues, including liquefaction and lateral spreading mitigation; consistency of earthquake ground motions; shallow foundation support; seismic uplift resistance; and avoidance of loading adjacent basement walls. The system was implemented by a technically-sophisticated owner through a process that included constructive collaborations between the project geotechnical engineer, structural engineer, general contractor, and specialty foundation and ground improvement contractor(s). The system is designed to cost-effectively provide a high level of seismic performance."

Jan 1, 2017

By Timothy L. Roberts

For many years practicing geotechnical and structural engineers in Texas and Louisiana were reluctant to include augered cast-in-place (ACIP) piles as a viable deep foundation alternate. Three primary concerns were the lack of a final driving resistance to confirm adequate capacity, the inability to inspect ACIP piles prior to installation, and the fact that pile integrity is highly dependent on the skill of the ACIP pile contractor's field personnel. The Deep Foundations Institute (DFI) Committee on Augered Cast-In-Place Piles has responded to these quality control concerns by establishing standards of practice for ACIP pile installation and ACIP pile inspection. Regional areas of the country have different subsurface soil and rock conditions and many times this will influence local installation and inspection requirements. The best way structural and geotechnical engineers can address quality control concerns is to be familiar with the DFI standards of practice, to know the special requirements for a particular project site, and to incorporate them into a well-written ACIP pile specification. The purposes of this paper are to: 1) review the main fundamentals of a successful quality control program, 2) describe how these fundamentals can be applied to the installation of ACIP piles, and 3) add personal experiences from ACIP pile projects in Texas and Louisiana. Nondestructive test methods are frequently used as a quality control tool to evaluate questionable piles. An additional brief discussion of two nondestructive test methods is presented to complete the paper.

Jan 1, 1998

By Ron Bromenschenkel

The State of California, Department of Transportation is currently retrofitting a major interchange near the San Francisco area. The project is located in a highly traveled area of Oakland with light rail commuter service near many footings. Over 600 micropiles are being used in conjunction with CIDH piles for footing stabilization. A specially designed Soil Nail pile will support footings for a new light rail utility structure. Pile testing features in this contract serve as points of interest for future foundation designs. The presentation focuses on substructure issues of this incterchange retrofit. Both design and construction considerations will be covered. Design Considerations: ? Project Description ? Structure inadequacies ? Design criteria ? Design contraints ? Retrofit strategy ? Consultant analysis ? Pile Designs and Test Sites ? Contract Specifications ? Construction Plan and Cost

Jan 1, 1998

By Gene Bryant, Wesley Schmutzler, Matteo Bertoni

The levees where the Mississippi River and the Lower Wood River meet near East Alton Illinois have been a problem area for years due to underseepage. The first phase of the deep cutoff wall was a 2,000-linear foot section that was completed in 2016 for the Illinois Flood Prevention District Council. This section was installed along the Wood River and the Mississippi river to depths of over 135’, The United States Army Corps of Engineers was tasked with continuing the cutoff wall along the Mississippi river. The wall was a continuation of phase I with depths up to 140’. The 1,000’ long cutoff wall was installed through fill, loose sands, cobbles, and sandy clay. The cutoff wall was terminated in either Glacial Till or sound rock. In order to provide wall permeability equal to or less than 1.0 X 10-6 cm/sec a self-hardening slurry (SHS) composed of ordinary Portland cement, slag cement, and water was utilized. The depths reached on this project using SHS is the deepest done to date in the United States. Along with the permeability requirements, a very narrow range for the unconfined compressive strength was specified at 50 – 180 PSI. In order to monitor the ground movement and water level fluctuations during the excavation of the panels with the Hydromill or Clamshell, 6 automated inclinometers were installed and monitored continuously during panel excavation in phase 1. Seven automated piezometers were monitored in phase 2. This paper will give an overview of the project with emphasis on the effect of the excavation on the instrumentation, specifically the reaction of the piezometers as the last panels were installed. INTRODUCTION The project is in Illinois, about 1000 feet downstream from where the Wood River Creek enters the Mississippi River between East Alton, IL and Wood River, IL adjacent to State Highway 143 (Fig. 1). The Wood River Lower Cutoff Wall Phase 2 Project (WR2) was awarded to TREVIICOS SOUTH (TIS) in September 2017. The Main Project features are: Construction of work platform, inclinometers installation and removal, cutoff wall construction by the Self-Hardening Slurry method (approx. 135,000 sf) up to 140' depth, clay cap installation, and site restoration. The levee system along this stretch of the Mississippi River has been plagued by under-seepage for several years. The phenomenon has worsened to varying degrees, depending on location, to the point that remediation was needed to ensure that Levee failure would not be an issue in the future.

Jan 1, 2019

? Hollow Stem Auger ? Drill Bits ? Leads/Torque Arm ? Hydraulic Gearbox ? Hydraulic Power Unit ? Grout Pump ? Crawler Crane

Jan 1, 2003

By Christopher M. Kenney

Augered-cast-in-place (ACIP) piles have been utilized on commercial projects throughout many parts of the country for years, but are only beginning to be scrutinized for use on major infrastructure projects and other critical structures in some regions. Numerous engineers are aware that ACIP piles are an economical foundation alternative, and many technical papers have been presented that provide reliable methods of estimating ACIP pile load capacity. However, designers may not yet appreciate that the load-settlement behavior of ACIP piles is very similar to that of drilled shafts. This paper analyzes ACIP pile case histories from throughout the country and demonstrates that ACIP pile settlement under applied load is consistent, predictable, and very similar to the documented behavior of drilled shafts. This paper also presents a simple but accurate method of estimating ACIP pile settlement at the design load, and illustrates the need to estimate the equivalent diameter of the as-built ACIP pile when estimating pile behavior. Finally, this paper presents back-calculated values of the drained elastic modulus from the ACIP pile case histories that may be useful to those using more sophisticated methods of estimating ACIP pile settlement.

Jan 1, 2001

By Sanjeev Malhotra

The American Petroleum Institute (API) method of predicting pile capacities in sands is reviewed. Factors that influence pile capacity such as soil parameters, pile parameters, loading effects and installation effects are listed. In addition, the simultaneous occurrence of physical phenomena such as grain crushing, pile shaking, stress-redistribution and plugging add to the uncertainty in the prediction model. To better understand the method of prediction, each parameter and the associated uncertainty is revisited. It is evident that these factors are inter­related and sometimes compensating. This discussion also draws attention to the influence that pile installation procedures can have on pile capacities and highlights the need for field experience with various pile installation procedures for designers. In summary, the strength of the method lies in its simplicity and ease of application, but the possible savings generated by an improved method are too substantial to ignore.

Jan 1, 2000

By Jean-Pierre Hamelin

Ground movements induced by underground excavation are always of critical concern, particularly in urban areas. Compensation grouting now appears as a safe means to control these movements. The paper presents new advanced systems developed by the specialist contractor to bring, at all stages of the project, an efficient control of operations and presents a case history taken from the project at Tren Urbano, Rio Piedras Section, constructed beneath an historic commercial section of San Juan de Puerto Rico.

Jan 1, 2000

By John P. Turner

The behavior of tieback retaining walls depends on many factors, including soil properties, groundwater conditions, construction sequence, spacing and stiffness of tiebacks and soldier piles, tieback loads, and others. The primary design considerations for tieback walls are 1) adequate stability and 2) limiting wall movements. Traditional design methods rely on apparent earth pressure diagrams and experience to predict the forces which must be supported by the tiebacks to provide adequate stability. The required soil properties depend upon whether the soil is sand, soft clay, or stiff clay. Design to limit wall movements is more difficult and the usual approach is to design the wall with an adequate factor of safety for stability and then evaluate wall movements during construction through the use of load tests on individual tiebacks and monitoring of wall movements by optical surveying, slope indicators, and extensometers. If excessive movements are likely to occur, it is often not known until construction is well underway. This approach is reflected in the fact that few tieback walls fail due to a lack of adequate stability, while most litigation involving tieback wall performance is related to excessive movements. Much progress has been made in recent years in methods for predicting the movement of all types of insitu retaining walls (Clough et al. 1989, Clough and O'Rourke 1990). These methods are based upon both experience and analytical methods. This paper reviews the methods currently available for evaluating both the stability and movements of tieback retaining walls. Case histories involving excavations constructed in the downtown Seattle area are used to evaluate the applicability of the available methods to Seattle conditions and to illustrate the importance of soil behavior in tieback wall performance.

Jan 1, 1990

Jan 1, 1985

By Mark R. Svinkin

Construction vibrations may be harmful to adjacent and remote structures, sensitive instruments and people. Construction vibration sources have a wide range of energy, displacement, velocity and acceleration transmitted on the ground. Effects of different dynamic sources and soil conditions on construction vibrations is analyzed. Consequences of construction vibrations are developed in various ways. It is important to assess intolerable vibrations before the beginning of construction activities. Guidelines for preconstruction survey are presented. Pre-construction survey and prediction of anticipated vibrations by IRFP method, monitoring and control of measured vibrations are important steps in preventing intolerable vibration effect.

Jan 1, 2000