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By Alessandro Bertero, Dylan Pearson, Wesley Schmutzler, Matteo Bertoni

"The SR 83/US 331 highway is located in the Florida panhandle, where it connects the Walton County beaches to the I-10 corridor. The roadway is of vital importance to the economy of the area as well as its safety since it represents the primary hurricane evacuation route from southern Walton County. The Florida Department of Transportation (FDOT) decided to increase the number of traffic lanes from two to four and improve the geotechnical properties of the moderately deep, very loose foundation soils, that had affected the highway rideability for years. The soil mixing was selected as the method to meet the unique deep ground improvement challenges of the project. The design required that Shallow Mixing Method (SMM) be used to build a 10-foot thick platform that transferred axial load to the bottom soil layers through a series of Deep Mixing Method (DMM) columns. Upon completion over 8,300 SMM columns and 1,500 DMM columns had been installed, with no remedial work required. Also, only 1% of the almost 1,500 specimens tested did not meet the specification requirements. This paper will describe the challenges encountered and provide valuable information that may be useful for other future projects, including details not previously published.INTRODUCTIONThe counties of Walton and Okaloosa have been a very popular vacation destination for many ears. The 50-mile long coastline boasts beautiful, sugar-white beaches and waters the color of emeralds. The popularity of the area has been growing even further, over the last few years. A consequence of this phenomenon is a fast-paced increase of the traffic flow on the SR83/US331 highway, especially at the bridge that connects the Walton County beaches across Choctawhatchee Bay (Fig. 1) to the heavily traveled I-10 corridor. The highway plays a very important role for the area also as a commercial link and as the primary hurricane evacuation route from southern Walton County. The increase in traffic has produced higher travel time, when not a complete traffic paralysis, and exacerbated the issue of ground settlement where accelerated wearing of road foundation occurred due to the presence of very loose, moderately deep, soils, that had afflicted the highway for several years. The Florida Department of Transportation (FDOT) decided to put an end to these issues by increasing the number of traffic lanes from two to four and improving the geotechnical properties of the foundation soils. The Design-Build Maximum Price Request for Proposal (RFP) issued for the expansion of the Choctawhatchee Bay Bridge saw the participation of numerous D/B teams which produced various technical solutions. Among them, the FDOT selected the Skanska/Parsons Brinckerhoff (General Contractor) proposal which provided for the use of soil mixing as the ground improvement technology. The design/build team assigned Foundation & Geotechnical Engineering (Designer of Record) the ground improvement design which Treviicos South (Specialty Contractor) would execute."

Jan 1, 2017

By Scott D. Thomson

The client for this project specializes in the use of state-of-the-art technology to fabricate and assemble composites and metal-bonded structures for commercial and military aircraft programs. One of the key components for this operation at the client's plant is a highly precise computer-numerical-controlled router known as the Shoda Machine. This machine tool was installed at the plant in July 1998 for the manufacture and inspection of aircraft parts, and it is extremely sensitive to deflections. To monitor the occurrence of deflections, an internal laser system continuously checks the machine calibration. Deflections in excess of 5/1000-inch in the foundation on which the machine rests require costly periodic re-leveling and recalibration of this tool. Therefore, a significant problem arose when measured deflections during machine operation were as large as 20/1000-inch. In addition, the foundation was cracked in at least three places as a result of elastic foundation movement caused by dynamic loading as well as shrinkage and loss of base support. Deciding on a remediation procedure to alleviate or eliminate these problems involved the following important considerations: (1) achieving the client's need for reducing deflections to less than 5/1000-inch, (2) minimizing the repair cost as much as possible, and (3) reducing the time required for implementation of the foundation remediation solution. After evaluating the advantages and disadvantages of several alternatives, jet grouting was selected as the most suitable solution. The jet grouting program provided columnar elements of soilcrete to remediate the Shoda Machine foundation.

Jan 1, 2003

By Joram M. Amir, Ernst Niederleithinger, Nikolaus Schneider

"Abstract: Diaphragm walls are used to provide a stable and watertight confinement for the construction of tunnels, underground railway stations, deep basements and other structures requiring deep excavations. Water seepage and soil loss through the joints have occurred on several occasions, causing extensive damage. This may have been due to uncontrolled concrete flow between the joints, unexpected geologic conditions or just poor workmanship.Different ways of quality assurance are applied on construction sites. Most of them rely on recording parameters of the construction equipment and conventional concrete quality control. In the frame of the EUREKA/ZIM project DiWaQ we have looked at several ways to perform non-destructive quality control. Some methods are to be applied after excavation before concreting (phase 1); others after the wall is completed (phase 2).For phase 1 we have used two different principles for checking the shape of the excavation, especially the joint to existing panels. A mechanical device which can be adapted to the excavating equipment was developed; field tested and validated on test and construction sites. It is described in detail in another paper in the same volume. A sonar-based device with a 10 mm resolution has shown good performance in the lab, but is still under development.For phase 2 different temperature sensors have been lowered into access holes to monitor the hydration heat developed during concrete curing. The same tubes can also be used to perform electromagnetic and ultrasonic crosshole measurements across or along joints to detect flaws. Especially the ultrasonic method has shown promising results on validation specimen at the BAM test site at Horstwalde, but limitations as well. Success substantially depended on the joint type, flaw size and distance of the sensors to the joint."

Jan 1, 2014

By Brian Langdon

The DRIVEN GROUT PILE was developed in 1989 by DeWitt Construction, Incorporated. This piling essentially consists of a cost-in-place concrete piling that reacts on a steel boot that is driven to bearing. This report will describe the driven grout pile, its background and its installation. The advantages and disadvantages of this system are also discussed. Finally, the results of actual field installations are presented and discussed. BACKGROUND The DRIVEN GROUT PILE was developed out of a need for a low-cost high capacity piling (100 ton) that could be installed with ordinary pile driving equipment. This search was motivated by attempting to incorporate the material economy of an auger-cast piling with the "empirical load test" of a driven pile. Typically, the least cost material for piling in the 100 ton range is concrete (grout). A grout shaft with minimal reinforcement can withstand a compressive load of 100 tons for a material cost in the range of $6.00 to $8.00 per lineal foot. A pipe piling with a capacity of 100 tons has a unit material cost ranging to $13.00 per lineal foot. The marriage of these two advantages resulted in the DRIVEN GROUT PILE. A pile that utilizes the economy of a reinforced grout shaft and has the loading confidence of a driven pile.

Jan 1, 1990

By Rudolph P. Frizzi

"Abstract Pile design for building structures in the United States is typically performed by: 1) investigating and assigning engineering parameters to the respective ground bearing materials, 2) calculating ultimate pile to ground (geotechnical) capacity which is then reduced by a Safety Factor deemed appropriate by a registered Design Professional thereby arriving at an allowable pile geotechnical pile capacity, and 3) determining the required pile structural section using allowable pile section material properties. It is advantageous to use a Working Stress Design Method (WSDM) approach as one system of loads (service loads) are used in both the geotechnical and structural evaluation. There are a variety of methods used to determine the ultimate and allowable geotechnical capacity, and Building Codes often require a registered Design Professional to determine the appropriate method(s) and capacities. The International Building Code is the Code typically referenced in building design and construction in the United States. Structural design usually follows Building Code requirements and Allowable Stress Design (ASD) procedures. As design of the overlying structure typically follows a Strength Design Method (SDM) approach using factored loads, in some cases piling is first designed for pile-to-soil interaction using service loads, followed by evaluating the pile geometry for factored loads. Construction is the finalization and implementation of the designed piling. As such, project-specific technical specifications are typically developed by a registered Design Professional such that a project Owner can bid, buy, and instruct a Contractor as to the desired piling work and acceptance criteria. There are several Industry groups, including DFI, PDCA, ADSC, and ACI that provide guidance documents which the registered Design Professional can refer to in developing the piling technical specifications. It is the author’s opinion that the registered Design Professional is best suited to observe and verify the piling installation; many Building Departments require verification and documentation by a registered Professional as a condition of final acceptance.INTRODUCTIONPile design for building structures consists of: investigation, design, specification, and verification. In major metropolitan areas within the United States, Building Codes typically identify minimum requirements for each of the above steps. The International Building Code (ICC, 2012) is the Code typically referenced in building design and construction in the United States. Recognizing the ground conditions as well as piling construction means and methods can vary on a site-by-site basis, latitude is given to the registered Design Professional and Contractor to optimize the piling system for the respective project conditions. Field testing and quality control / assurance measures are typically implemented to verify the design intent is attained for the production pile elements."

Jan 1, 2014

By Carl D. Ealy

Work is being done to web enable the FHWA Deep foundation Load Test Database. Originally designed to function in the client server environment via modem, access to the database both for data maintenance and user queries has been upgraded to take advantage of the Internet and current and future information technology innovations. The DFLTD will be part of an Automated Geotechnical Information and Design Aid System, the object of which is to assist those involved with managing and maintaining our nation's highway infrastructure. The system will also meet the needs of university and other research institutions for a statistically meaningful source of high quality data for the development and verification of improved analysis methods, in-situ testing methods, etc.

Jan 1, 2002

By Bernard Hertlein, Chia K. Tan

"The move to LRFD methods for structural design by AASHTO, ACI, AISC , ASCE, and the FHWA has been a major change for the American construction industry. The deep foundations industry has arguably been placed most at risk by this situation, because of the need for, and the difficulty of providing, reliable quality assurance.LRFD is attractive for both the owner and the engineer because it promises cost reductions, but the assumption underlying LRFD is often overlooked - that the acceptable margin of safety can be rationally reduced, thus saving costs, provided that all the factors involved are closely controlled. This means that both the quality of the materials and the quality of the construction work must be closely monitored, and held to an acceptable standard.This paper describes the type of comprehensive quality management program that is needed in deep foundation construction projects based on LRFD. Case histories are used to illustrate the importance of both adequate inspection and reliable testing to a comprehensive quality management program.IntroductionOver the last thirty years, the major organizations that set standards and practice policies for the American construction industry, such as the American Association of State Highway and Transportation officials (AASHTO), the American Concrete Institute (ACI) , The American Institute for Steel Construction (AISC), the American Society of Civil Engineers (ASCE), and the Federal Highway Administration (FHWA), have embraced Load and Resistance Factor Design (LRFD) as an alternative to, and in some cases, a complete replacement for, Allowable Stress Design (ASD). AASHTO first published a new set of LRFD-based design guidelines for bridges in 1996, with several revisions in 1997, 1998, and 1999 (AASHTO, 1996). The 1996 AASHTO Bridge Design Code was the first in the United States that required foundations to be designed using LRFD procedures. LRFD has a clear advantage over conventional ASD where variability in material strength, bias in design methodology, and degree of construction quality can be rationally accounted for to achieve an acceptable level of risk."

Jan 1, 2005

By Brian J. Olson, Kevin Haiar

Originally constructed between 1939 and 1941 as part of Franklin D. Roosevelt’s New Deal programs, the Bonneville to Hood River 115 kV Transmission Line required an infrastructure upgrade to remain reliable and in-service. The line traverses the rugged landscape of the Columbia River Gorge on the Oregon- Washington border, featuring steep, talus slopes; uneven, rocky terrain; and a variety of environmental sensitivities. This paper details the design and construction of 27 micropile foundations for new, fire- hardening steel poles through a particularly challenging stretch of the alignment. The difficult access and environmental constraints at these sites designated them as helicopter-accessible and precluded the collection of detailed geotechnical information prior to construction. Micropiles provided a viable foundation alternative due to their portability and flexibility during construction. Detail will be provided on the extensive preliminary desktop study performed, as well as the process of developing engineering designs to successfully accommodate for variability and unknowns in complex geological conditions. With an increasing number of electric power projects traversing challenging terrain and facing similar obstacles, this project stands to provide valuable lessons learned to the industry.

Sep 8, 2021

By Tracy Brettmann

The Highway 146 Bridge Expansion Project across the Clear Creek Channel in Houston, Texas was designed on driven precast concrete piles. However, during construction, the piles along one side of the bridge along the main channel encountered obstructions and couldn’t be installed. These obstructions turned out to be the remnants of a previous bridge foundation at this location, which was unknown to the designers since that bridge had been demolished 40 years ago. Those old foundations were massive 20 ft by 40 ft (6 m by 12 m) pile caps 11 ft (3.3 m) thick supported on precast concrete piles 37 to 55 ft (11 to 17 m) long. The foundation re-design for these locations involved installing a single 78 inch (2 m) diameter drilled shaft up to 125 ft (38 m) long to replace the originally planned driven pile supported pile cap. The drilled shafts would need to be installed within very tight tolerances since they were supporting a single bridge column directly above it. In addition to drilling through the obstructions, this work would need to be completed from barges in 30 ft (9 m) of water capable of dealing with both the current and tides affecting this area. The shafts were installed using a multi-step process. The first step involved coring a larger diameter 100 inch (2.5 m) hole through the reinforced concrete pile cap and removing the concrete inside. This was followed by the installation of a 72 ft (22 m) long permanent casing to and removing the soil and existing precast piles inside. Finally, the drilled shaft excavations were advanced to the completion depths (uncased) using bentonite slurry as the support fluid.

May 1, 2022

By Jakub Szary

Excavation and shoring adjacent to the above-grade Gilmore train station and elevated guideway was undertaken in 2019. A perimeter secant pile cut-off wall was constructed to a depth 37 m (121 ft) below ground surface consisting of 1.0 m (3.3 ft) diameter drilled piles spaced 750 mm (2.5 ft) on-center, tied back with soil anchors, and reinforced with W610 steel sections every 4th pile. A bracing/jacking system was also constructed to support 3 free-standing guideway caissons within the excavation. An automated instrumentation program was installed to monitor movements of shoring walls and train infrastructure in real time and consisted of a robotic total station, inclinometers, tiltmeters, strain gauges, extensometers, and anchor load cells. Baseline monitoring was able to establish diurnal and seasonal movements within the structure, strongly correlated with temperature. The system actively monitored various shoring elements and train infrastructure in real time and alerted the project team when values exceeded predetermined threshold values. Remote reconfiguration of the automated system allowed for more frequent monitoring during jacking of Pier 29 in March 2022. Monitoring data was in agreeance with on-site manual surveying results and jacking dial gauges, and proved to be a reliable monitoring system for construction applications.

Sep 1, 2022

By G. R. Dasari

New Austrian Tunnelling Method (NATM) has been analysed by Finite Element method in two and three dimensions by Strain Dependant Modified Cam Clay (SDMCC) Model. The effects of construction sequence, stiffness of shotcrete and time dependency of shotcrete on surface settlement magnitude due to the NATM have been studied. Settlements obtained in 2D analysis, as expected, found to be more than the observations. The surface settlements obtained in 3D analysis found to be about 3 times less than equivalent plane strain analysis. This is due to mobilisation of soil strength around the tunnel face and soil-tunnel lining interaction. About 40% settlements occurred due to excavation of face at the monitor section and 60% after the excavation crossed monitor the section.

Jan 1, 1996

By Jesse R. Jacobson

A large casino complex in Cherokee, North Carolina recently underwent a $633 million expansion that involved substantial foundation challenges. The site is located in a valley on the southern edge of the Great Smoky Mountains National Park, where subsurface conditions typically consist of varying thicknesses of fill overlying alluvium, residuum, partially weathered rock and rock. The fill and alluvium contain cobbles and boulders as large as several feet in diameter. The residuum and partially weathered rock are very thick in some areas, and the depth at which consistently high quality rock is encountered is highly variable. To reduce the foundation costs for the expansion, continuous flight auger (CFA) piles were proposed in lieu of micropiles. CFA piles are not generally used in this geologic environment and concerns regarding their selection included: (1) an uncertainty that CFA piles could be successfully constructed given the difficult conditions and (2) a lack of regional data regarding unit resistance values and load transfer characteristics. To address these concerns, a design-phase test program was undertaken to evaluate pile constructability, develop an understanding of the load transfer behavior, and establish the required pile lengths. The program included soil test borings, shear wave velocity measurements, timed auger probes, instrumented pile load tests and observation of exhumed piles. It was demonstrated that CFA piles could be advanced through the fill, cobble/boulder-laden alluvium, residuum and into the partially weathered rock, albeit with some limitations. Under axial loading, the pile response was very stiff and relatively high unit resistance values were measured. Pile instrumentation allowed for the evaluation and use of design pile lengths shorter than that tested, and the overall reduction in pile lengths yielded a 40 percent reduction in foundation cost. In general, CFA piles were determined to be a suitable, economical foundation alternative.

Jan 1, 2011

By M. England

Keywords: Bi-directional tests, Osterberg cell, O-cell®, static load tests, Timeset® Static load testing, where loads are applied vertically to the top of the pile and often referred to as 'top down testing', has been used for many years and has become a 'standard' test for the world of foundation engineering. The method, although well developed, cannot be used under certain circumstances, magnitude of load being a particular issue. There is a finite limit to the load capacity that can be applied with either kentledge, the use of reaction piles or anchors, and as the loads increase, the costs escalate dramatically. A novel test method seeks to overcome all the associated problems of large scale and restrictive area "top down testing", utilising static load testing techniques. The method requires the foundation element to be divided into two or more sections and these can be loaded axially as required using a portion of the foundation element as a reaction. This paper presents some recent applications and developments in the use and application of the bi-directional testing technique using the Osterberg Cell or O-cell® and outlines some of the many advantages of the system. Recent bi-directional test loads applied to bored piles have mobilised capacities of 279 MN and with flight auger piles up to 25 MN.

Jan 1, 2006

By James S. Graham

Foundation pile driving hammers used in New York City in the past 100 years have been drop, steam, compressed air, diesel, and hydraulic. In 1992, the first hydraulic hammer in the New York City area was purchased by Norwalk Marine Contractors, Inc. from Junttan in Finland. It was bought because of its variable energy and ease of mobilization, not because of its higher transferred energy. Heller and Johnsen engineers instrumented hydraulic hammers on nine jobs. The measured transferred energy for the nine jobs was found to average approximately 80 percent. There is no clear consensus regarding the reasons for the hydraulic hammer being more efficient in delivering energy to the pile as compared to single-acting steam/air impact hammers. To minimize pile damage during installation, and to minimize footage overruns, an up-to-date version of the wave equation software that includes an efficiency value of 0.95 for hydraulic hammers is now used.

Jan 1, 2000

By Robert C. Rabeler

Soil and Materials Engineers, Inc. (SME) has utilized drilled cast-in-place (D-CIP) piles on a number of projects in the midwest. These foundation systems have typically consisted of drilling an 8 to 9-inch diameter borehole with a rotary type drill rig or driving a casing with a small hammer. A structural steel member is installed in the center of the excavated space, and the borehole or casing is grouted to complete the installation of the D-CIP pile. This type of piling system has also been called: mini-pile, micro-pile, or drilled-in pier. The capacity of these piles varies depending upon subsurface conditions, as well as the structural capacity of the pile. The structural capacity can be modified based on the size and yield strength of the structural steel member. SME has used the D-CIP piles for underpinning of lightly-loaded structures for a number of years. Steel brackets can be welded to the structural steel member in the center of these piles, and the bracket extended underneath existing foundations to provide proper foundation support. D-CIP piles have also been used for new construction where access was limited. Recently, SME had the opportunity of providing design as well as construction monitoring services for a unique project where these piles were used, but at much higher capacity. The project involved adding seven additional floors on top of a five-story building (total of 12 stories). New columns were extended through the existing building to support the new floors. Access to construct foundations was available to one level of underground parking beneath the structure, as well as to a basement area. Access required equipment to travel through a 3-foot wide hallway. A special duplex drilling machine was used to access the foundation locations and to install the piles in a limited headroom condition. Eight-inch diameter D-CIP piles were extended to a depth of approximately 40 to 50 feet below grade and socketed into a dense clay till or sandstone, and No. 18 or No. 20 threaded bars were installed in the center of these piles. The design pile capacity was as high as 190 kips and were verified by a compression load test. The load test was performed with limited access and headroom. These piles were installed by Spencer White and Prentis Foundation Corporation (SWP). For conditions where rock or hard soils are encountered at reasonable depths, D-CIP piles can provide working load capacities comparable to larger driven steel piles. The ability of the equipment to access very restricted areas, combined with the high capacities results in a very attractive solution to a number of difficult foundation problems.

Jan 1, 1999

By Stefano Trevisani

Abstract The FIEC Sustainability Vision states that “risks should be identified and allocated in a fair manner across the project team from the early stages of the design phase. A partnering approach, where objectives and timescales are agreed in advance together with all relevant partners in the value chain, offers a useful solution to improve on site efficiency and reduce disputes”. An alliance or collaborative form of contract involving all parties is the best way to ensure fair contract conditions and proper risk allocation in construction projects. Collaborative contracts are particularly useful where there is uncertainty or undefined information or in the event of technical difficulties and other risks difficult to allocate among the parties involved in the project. Owners sometimes require even special output in terms of innovative technical solutions or special performance. In addition, this particular form of cooperation has been construed and developed with the intention of avoiding and mitigating another great risk associated with the construction industry (especially in complex projects): disputes and conflicts, which are often a major cause of delays, increased costs, loss of reputation and opportunities. In contrast, Alliances are a way to increase and strengthen business relationships, technical and economic innovation and effectiveness, in a worldwide global context where the waste of resources must be avoided in order to guarantee future recovery and growth. Of course, the total cost of a project is usually a key factor and the main driver for the Owner and the Contractors in deciding the type of relationship between them as well as the subsequent relationship with subcontractors and lower-tiers. This paper and presentation, will explain the main features and the principle benefits that the use of collaborative contracts can bring to all parties involved in the construction project, including the sustainable financial return that might be achieved if costly and time consuming disputes can be avoided.

Jan 1, 2014

By Patrick J. Hannigan

The pile foundation designer typically performs a subsurface exploration program and static pile capacity calculations before selecting a pile foundation type, length, and capacity. During construction, a pile installation criterion must be established to meet these design requirements. This installation criterion usually consists of a minimum penetration resistance or blow count to confirm pile capacity and may also include a minimum embedment requirement. This text will focus on use of wave equation analysis and dynamic measurements to meet design requirements. BEFORE THE WAVE EQUATION Since the mid-1800s, over 450 dynamic formulas for pile driving control have proliferated. In their simplest form, these formulas relate hammer energy to the work of soil resistance, or simply: W ? h = R ? s (1) Where W = ram weight h = ram drop height or stroke R = pile capacity s = pile penetration per blow

Jan 1, 1990

By Sam Warren, Antonio Marinucci, Genesis Z. Figueroa, Anne Lemnitzer

Drilled Displacement Piles (DDP) provide an ideal deep foundation solution that combines the benefits of ground improvement with traditional advantages of piling systems. This paper consolidates data from 20 construction projects in which more than 30 DDPs were installed and tested axially. High quality site exploration data (e.g., Cone Penetration Test and Standard Penetration Test) were evaluated to derive geotechnical analysis parameters. The test sites consisted of mostly mixed soil types with strongly stratified layers of sand, silt, and clay. Pile diameters ranged between 40 cm and 61 cm. Test results were compared with predictive methods developed specifically for DDPs as well as methods used in general geotechnical practice. The accuracy of the empirical methods is presented in terms of total pile capacity, pile length/diameter, and soil type. The large majority of all examined methods underpredict the in-situ pile capacities. It was also found that the difference between the tested and predicted capacity is strongly related to the level of improvement in the surrounding soil due to the piles’ installation. A general comparison between predictive axial accuracy and the observed level of ground improvement upon installation is also discussed.

May 1, 2022

"The development of non-destructive testing (NDT) methods for deep foundations occurred in several parts of the world, gradually coming together into the present state of the art. The compilation of this brief NDT history is the best effort of several knowledgeable members of the Deep Foundations Institute (DFI) Drilled Shaft Committee, coupled with the recollections of several historically important contributors to the science. It is not intended to be exhaustive, but rather concentrates on the origins of the methods in common use and on which this manual focuses.Modern NDT methods, and the spread of knowledge about them, have expanded through application to real foundations projects by the original researchers, sometimes inspired by their own curiosity, sometimes to respond to the cost and time limitations imposed by static testing, and sometimes to address the questions raised on research projects funded by large government agencies such as the Federal Highway Administration (FHWA) in the USA, and various European transportation agencies. Initial attempts were primitive by today’s standards, and equipment limitations often restricted successful application to relatively simple cases. As electronics improved and confidence in them increased, the early researchers began commercial promotion of their methods, published their findings in professional journals, and shared experiences at conferences held by such groups as the DFI, the International Association of Foundation Drilling (ADSC), the International Conferences on the Application of Stress-Wave Theory to Piles and other venues such as ASCE and Transportation Research Board (TRB) conferences.NDT methods were developed to fill a need to assess the quality assurance of deep foundation elements. New pile types and higher design loads prompted engineers to verify the safety of their foundations via additional testing during construction. Static load testing was the traditional method to assess performance, and this method has been used for centuries and perhaps even millennia.Relatively recent alternatives to static load testing for determining the capacity of drilled shafts include the bottom load test method. This method uses a jack embedded in the lower portion of the pile (bottom load test) and was first reported to be used from Canada in the early 1970’s (Gibson& Devenny 1973). The concept immediately caught on in Israel, where it was used as a quality control measure for small-diameter piles drilled in rock (then a new technology). The method was later patented in the US by Jorj Osterberg, and offered as a commercially available service in thelate 1980s (Osterberg, 1989)"

Jan 1, 2004

By Peter Cali, David Yang, Rakshya Shrestha, Ralph Griffin, Sushil Kafle, Motoji Watanabe

"As a part of the ‘US Army Corps of Engineers - New Orleans to Venice, Louisiana Hurricane Protection Project’, deep mixing ground improvement was designed to reinforce the soft ground for the emergency repair of a 7297-foot (2,224 m) long section of the Mississippi River West Bank levee in Buras Levee District under the contract ‘Emergency Levee Repairs – Contract P-17A, Plaquemines Parish, Louisiana’. The ground improvement utilizes a series of soil-cement panels oriented in the transverse direction of the levee. Each soil-cement panel consists of overlapped columns installed by the deep mixing method (DMM). DMM is performed from the existing top of levee and extended to competent stratum at depths varying from 26 feet (7.9 m) to 47 feet (14.3 m) below the working platform. The main purpose of the DMM panels is to provide shear resistance to the levee against lateral loads at high flood water condition. The DMM panels support the additional vertical load created by the increased height of the levee for hurricane protection and control the long-term settlement of the remediated levee, which might otherwise occur due to the compression of soft foundation soils. The total amount of DMM treatment is approximately 54,000 cubic yards (41,500 cubic meters). This paper reviews the project background, subsurface soil conditions and presents the design, construction and quality control of the deep mixing work for this levee repair project.INTRODUCTIONIn August 2005, Hurricane Katrina caused major damage to the federal and non-federal flood control projects in southeast Louisiana. In September 2005, Hurricane Rita caused further damage to this flood protection system. In an effort to minimize further damage and to enhance the protection level, certain non-federal levees located on the west bank of the Mississippi river in Plaquemines Parish, Louisiana were incorporated into the New Orleans to Venice Hurricane Protection project by the US Army Corps of Engineers (USACE). DMM techniques were then utilized by the USACE in several of these emergency projects and in many medium sized projects between 2006 and 2010 (Bruce et al. 2012). This project (called P-17A hereafter) which forms a part of this protection system is executed under the contract Emergency Levee Repairs, Contract P-17A. This is one of the largest projects of the USACE after LPV- 111. The huge LPV-111 project (5.5 miles (8.9 km) of levee) treated by DMM), the largest DMM project ever conducted outside Japan, began in 2010 and was completed in 2012 (Cali et al. 2012, Bruce et al. 2012).DMM is utilized at P-17A to construct a series of soil-cement panels oriented in the transverse direction of the existing levee to provide shear resistance to the levee against the lateral load during high flood water condition. The project extends 7297-foot (2,224 m) along the West Bank Levee of the Mississippi River in the Buras district of Louisiana, parallel to Louisiana Highway 23 (LA-23) as shown in Figure 1. It is located approximately 60 miles (96 km) south-east of downtown New Orleans."

Jan 1, 2015