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By Allan Sylvester

This paper will discuss the design, construction, and performance of the support of excavation on the San Diego State University LRT Station. The vertical elements of the system include drilled secant piles and drilled soldier piles. We will discuss the geo-technical characteristics, design and construction considerations, loading criteria, construction techniques, schedule constraints, and performance of the pile and support of excavation systems. In consideration of the conference theme, there will be a discussion of the successful accomplishment of meeting the interim milestone dates of the Contract. The project team cooperatively worked to design and install approximately 1,100 drilled secant and soldier piles as well as excavate and install the balance of the support of excavation elements in such a manner as to minimize the disruption to campus students and operations.

Jan 1, 2002

By P. Dupeuble

Diaphragm walls, owing to their method of construction are discontinuous structures. A new technology for the construction of joints between panels has been developed. This new process allows for the construction of diaphragm walls with mechanical and watertight continuity.

Jan 1, 2010

By James Green

It has often been said that the best contracts written are by people who are suspicious of each other. The Spanish philosopher, Ortega y Gasset, said: "Every contract is an Act of Distrust." The arena for dispute settlement outside of the courts is increasing day by day - contracts, especially construction and civil engineering contracts, are written containing arbitration clauses for settling disputes - the very drafting of standard forms of contract, do in some instances by their very construction, create an ambiguity as to intent and provide a breeding ground for dispute. I come from a land far across the sea - the most southern land before the South Pole. Being a young country, 150 years old, we are still progressing - being far removed from the trouble free zones of the world and nuclear free we enjoy a lifestyle second to none.

Jan 1, 1987

By Larsson Lars-Erik, Rani Isa, Martin Jönsson, Håkan Bredenberg, Mats Larsson

"IntroductionSteel Core Piles are used extensively in Scandinavian countries, where hard rock is found within reasonable depths. A steel core is cast into a drilled steel tube casing and a rock hole is extended below the casing. This pile type is considered a very reliable type of pile, and for urban environment it has several advantages compared to other types of piles. One critical phase of the installation is the drilling of the casing. Usually a DTH (Down The Hole) hammer is used. Drilling in fine grained soils, e g silt, below the ground water level, may give rise to an excessive volume of soil material flushed up from the point of the casing, resulting in unacceptable settlements around the pile installation area.Using a new method for drilling of the casings, the ELEMEX-method has proven to significantly reduce the risk for such problems. In the paper a case record from a ground improvement project in central Stockholm is described. Ground settlements around the drilling area were carefully monitored over a longer period. Both the new drilling method and the conventional DTH casing drilling method where used, so that the corresponding ground settlements could be compared. Settlement records and comments are included in the paper.The paper also gives a description of the project. The installation of new piles and foundation constructions cover a whole city block in Stockholm downtown. The reason for the replacement of the old, damaged wooden piles were due to their destruction caused by a long time lowering of the ground water table. The paper gives a description of the new drilling method as well as an overview of usual urban foundation issues and their solution in Sweden, Finland and Norway.Drilled Foundation MethodDrilled Foundation, using drilling methods originally developed for drilling of large diameter rock holes, is today a standard method for the installation of piles, tiebacks, drilled pile walls and other foundation components, especially in urban built up areas where other techniques as drop hammers, augers, vibratory hammers and other equipment fail to meet the requirement, se ref(1). Drilled foundation is for example used for"

Jan 1, 2014

By Jared M. Green

This paper presents the wall stabilization design and implementation for a 541 linear ft masonry and concrete gravity-type retaining wall flanking the west perimeter of a 7.37 acre parcel in Bronx, New York. This paper will discuss the results of static and dynamic stability analyses performed for the pre- and post excavation phases for the proposed 300 ft wide open-cut of up to 14 ft of contaminated soil below the toe of the retaining wall. The wall stabilization consisted of over 74 inclined drilled and grouted anchor dowels, and 55 tiebacks drilled and grouted to the underlying mica schist bedrock. Three over-lapping rows of jet grout columns were chosen as the foundation solution for the existing retaining wall. This paper focuses on the design, construction and performance of the jet grout curtain wall. The jet grout wall served three purposes: 1) underpinning and excavation support for the removal of contaminated site soils, 2) permanent hydraulic barrier, and 3) resistance against a deep seated failure within the thick clay layer present at the site. The originally designed jet grout wall had unexpected negative effects to the existing retaining wall. The jet grouting program was modified while the Observational Method (Peck 1969) was employed to keep wall movements to a minimum. This paper discusses the diagnostic methods used to determine the cause of retaining wall movement; the implementation of a remedial ground improvement program; the modification to the jet grout installation procedure; and the ultimate performance of the jet grout wall.

Jan 1, 2011

By Clyde Baker

Drilled shafts for many situations offer an economical alternative to driven piles. The Federal Highway Administration (FHWA) has spent considerable time and money in research and developing design and construction guidelines for drilled shafts. However, the full potential of the technology may not be realized because of the uncertainty of the effects of construction on the actual service behavior and the lack of either reliable quality control tests to check for or evaluate defects, or inexpensive load test procedures. Static load testing is very expensive and it is not feasible to load test each shaft on a project. Therefore, other means are necessary to confirm or evaluate the integrity of the completed drilled shaft or to determine the capacity of the completed shaft.

Jan 1, 1989

By S. T. Kok

This paper presents a case study in West Malaysia for passive piles failure in very soft marine clay in open excavation. In this particular case, the thickness of the very soft marine clay ranges from 5 m to 7 m (16 ft to 23 ft) from the ground surface. Preliminary site investigation reported SPT ?N? value of zero for the very soft marine clay. The design was based on a deep foundation utilizing driven piles to support the superstructure. During pile cap construction, the piles were subjected to uncontrolled open excavation, inducing bending moment in the piles, resulting in some cracked and broken piles. Analyses were carried out using an existing three-dimensional finite element code with a non-linear soil model to predict the response of these piles during excavation. Finally, the predictions of pile responses during excavation were compared satisfactorily with the observed results.

Jan 1, 2009

By Ian Vaz, Takefumi Takuma

"The New Orleans area has been repeatedly flooded by major storms and hurricanes since its French colonial era. After severe flooding in May 1995, the U.S. Congress authorized a massive flood protection project called the Southeast Louisiana Urban Flood Control Program (SELA) in 1996 to improve interior drainage in Orleans, Jefferson, and St. Tammany parishes. However, the project was not fully funded before the landing of Hurricane Katrina in 2005 and Hurricane Rita, which breached many of the area’s levees and flooded 80 percent of the city. Finally, the project was fully funded in 2008 and has been worked on towards its 2017 completion. Another large project simultaneously worked on in the area is the Hurricane and Storm Damage Risk Reduction System (HSDRRS). This system was designed for a 100-year level of flood risk reduction. One particular project within the HSDRRS rendered successful due to an unconventional method of pile driving that was utilized to install sheet piles to reinforce an existing concrete I-wall. This paper will discuss how and why this non-vibratory method of sheet pile installation allowed the project to be successfully completed ahead of schedule.INTRODUCTIONSteel sheet piles were utilized on many of the SELA and HSDRRS projects for permanent cutoff walls under concrete I-walls or T-walls or for temporary earth retaining walls of drainage structures. Although the SELA Project was established in 1996 after severe flooding the year before, hardly any work was done on it until the two catastrophic storms Hurricanes known as Katrina and Rita triggered its revival. These two hurricanes also triggered the HSDRRS soon after the storms’ devastation. The SELA project authorized to improve interior drainage systems while the HSDRRS project was authorized to raise or restore levees and floodwalls mainly along Lake Pontchartrain, the Mississippi River, and Lake Borgne in addition to other areas. Figure 1 shows the SELA Projects that have been completed, are still under construction, or approved for construction. The projects fully highlighted in yellow within the map specified the press-in piling method. These improvements included drainage systems, pump stations, surge walls, and outfall canals as enhanced protection for future storms similar to Hurricane Katrina that caused so much damage by inundating the New Orleans area in August and September 2005 respectively (Facts and Figures, 2012). The completion of these projects were the responsibility of the U.S. Army Corps of Engineers, New Orleans District.Due to the fact that many of the projects were in densely populated areas, the Army Corps of Engineers specified a non-impact, non-vibratory press-in piling method for driving and extracting sheet piles for many of the projects to mitigate noise and vibration impacts. The soft soil conditions in the New Orleans area was also a contributing factor in the Army Corps of Engineers’ decision to specify this piling method due to the risk of settlement for existing historical as well as modern structures. In addition, there were other projects that elected to use the press-in method without any contractual requirements. One of these projects was the Inner Harbor Navigational Canal Reach II Emergency Interim Repair which was part of the HSDRRS project that has been under construction since its authorization in 2005 (Facts and Figures, 2012)."

Jan 1, 2017

By Tomohide Takeyama, Yuki Yoshida, Masaki Kitazume

"Abstract A series of centrifuge model tests was conducted to investigate the failure pattern and stability of cement treated clay ground having an unsupported vertical slope. The model ground was subjected to monotonically increasing centrifugal acceleration until it failed due to the enhanced self-weight. The test results were compared with the numerical analyses in which the treated soil was simulated by the Smoothed Particle Hydrodynamics (SPH) method. In the simulation, the Dracker- Prager model is employed as the constitutive model. In order to simulate the brittle behavior of the cement treated soil, it is assumed that the unconfined strength is gradually reduced to a certain value which corresponds to the residual strength due to accumulated plastic strain. It was found that the simulation by using SPH method can express the brittle failure observed in the centrifuge model tests.IntroductionBecause of economical and environmental concerns it has become more difficult in recent years to obtain enough soil to construct reclaimed land for airports, electric power plants, manufacture plants and so on. On the other hand, it has become difficult to find and construct disposal sites for waste subsoil or dredged soil. These circumstances have encourage geotechnical engineers at present to use these poor quality materials as filling materials more than they were used one or two decades ago. Several soil admixture methods have been developed to improve their properties and to manufacture high quality fill materials.The deformation and strength characteristics of cement treated soils have been investigated in Japan, which have revealed that the treated soil is characterized by a brittle behavior with quite high compressive strength and quite small strain at failure, and the treated soil with relatively high strength shows tensile failure instead of shear failure. Regarding to evaluate the stability of structures adjacent to or buried in the treated ground, Kitazume (1998) and Kitazume et al. (2003) investigated the earth pressure of cement treated ground by the centrifuge model tests. And they emphasized that the failure pattern of the cement treated ground was much different from that of ordinary ground. After the Hyogoken- Nambu earthquake in 1995, many design codes for the seismic stability were revised in Japan, so that seismic stability must be evaluated more precisely. The dynamic earth pressure of ordinary grounds is usually calculated by a pseudo-static limit equilibrium method based on the Mononobe- Okabe’s method (Okabe, 1924; Mononobe and Matsuo, 1929). This calculation method is also applied to the cement treated ground, although its applicability has not been thoroughly clarified."

Jan 1, 2014

By Jim Steding

L.G. Barcus and Sons, Inc. recently completed a three-phase project for the expansion of Presbyterian Hospital in Albuquerque, New Mexico for McCarthy Construction Co., the Construction Manager for the project. It was a challenge that allowed Barcus to demonstrate many of it's strengths. Safety of people and property, restricted access, low headroom conditions, extensive planning to maintain hospital operations and a tight schedule were all key elements affecting the successful installation of the Augered Cast-In-Place Piles. Phase I began with installing and performing a 450-ton pile load test on an 18-inch diameter Augerpile 65 ft long. The load test was installed and performed directly in front of the Emergency Room entrance. Space was limited and the E.R. had to remain open with uninterrupted ambulance access. The results of the load test were outstanding. In fact the test pile performed so well that some of the job piles were shortened from 75 ft long to 65 ft long. [ ]

Jan 1, 2003

By Timothy D. Stark

Jet grouting has increasingly become one of the ground improvement technologies used to address seepage concerns and to provide strength improvement of soils. The technique of jet grouting uses high pressure/velocity jet fluids to erode the existing soil and then to mix the cuttings with cement slurry to form soilcrete. Excess slurry or spoil is ejected to the surface. If the native soil is not completely mixed with slurry, the resulting columns will have soil inclusions which can reduce the strength of the column and/or increase the permeability of the column. A jet grout test program at Tuttle Creek Dam shows that the completed large diameter columns contain perhaps 40 to 50% or more of native soil that was not broken up and mixed during the jet grout process. The test program included excavation of full-scale columns to a depth of 35 ft (10.7 m) for visual inspection and testing. Additionally, six of the columns were cut or sectioned to investigate the interior of the columns. The observed inclusions include significant amounts of both fine grained (silts and clays) and coarse grained (fine sands and sands) soils. Evidence suggests at least two explanations: (1) fine grained soils can be difficult to erode and break up into small enough particles that can be ejected to the surface, especially if at low natural water content, and (2) when large diameter columns are being excavated, the excavated roof of the cylindrical cavity may be unstable and may collapse. With this roof instability large slabs of material can break off, fall into the slurry and escape the cutting and mixing action of the rotating jets. This paper describes the Tuttle Creek Dam test program, inclusions observed in the completed columns, and suggests potential causes of the inclusions.

Jan 1, 2009

By Elizabeth M. Smith

The kcICON design-build project in Kansas City, Missouri includes widening the existing roadway, improving interchanges and grade separation bridges, and replacing the Missouri River Bridge. The Missouri Department of Transportation (MoDOT) typically utilizes steel H-piles and steel pipe piles as driven pile support for bridges. After bidding the kcICON project, the cost of steel rose significantly and the design-build contractor used an innovative approach to reduce foundation costs without significantly affecting the project schedule. The kcICON team conducted a value engineering evaluation of alternative foundation types for use at four grade separation structures. The result of the value engineering evaluation was selection of precast, pre-stressed concrete (PPC) piles as the preferred foundation alternative. Terracon developed a test program to evaluate the performance, capacity, and suitability of PPC piles at the site using a PDA and CAPWAP analyses. This paper presents the value engineering design, rationale for selection of PPC piles, results of the pile test program, and findings during production pile driving. The collaborative approach to the project by MoDOT and the kcICON team, combined with testing and a site-specific design approach, resulted in substantial savings for the design-build contractor.

Jan 1, 2009

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 Robert A. Field

Static-Load Piledriving utilizes a hydraulic push to facilitate the installation of a pile. The pile is not rotated, impacted or vibrated. A smooth pushing force advances the pile incrementally into the ground. Static-Load devices must have a reaction mass to push against. The most simple form of a Static-Load device is a jack; more advanced equipment, such as the Still Worker, also utilizes this approach. This paper focuses on the use of the Still Worker on three challenging projects. In each case, the existing site conditions made it risky, or unattractive, to utilize conventional impact, vibratory, or drilled-shaft equipment.

Jan 1, 1997

By R. G. Horvath

The Statnamic loading test is a new and innovative method for testing deep foundations. The test is relatively inexpensive, quick, easily mobilized, provides for direct measurement of applied load and corresponding displacement, and is capable of very high loading capacities. The long duration of the applied loading, as compared to a dynamic loading test, allows for a straightforward determination of the static behaviour of the foundation tested. A new method of analysis of the Statnamic loading test, the Equilibrium Point Method, is presented. A description is given of the pile-soil model and a demonstration of how the static load-displacement behaviour of deep foundations may be predicted from the Statnamic loading test data. The Equilibrium Point Method of analysis is applied to three types of deep foundations in soils which respond differently to fast loading rates. These case histories, from Canada and the United States, include data from static loading tests for direct comparison, and demonstrate the ability of the Equilibrium Point Method to predict static behaviour of the deep foundations.

Jan 1, 1993

By D. Michael Holloway

The realignment of Interstate 880 replaces the double-decked (Cypress) viaduct collapsed in Oakland, California during the 1989 Loma Prieta Earthquake. The California Department of Transportation (CALTRANS) evaluated several pile foundation schemes for supporting the proposed structures. Structural support demands led to the selection of steel pipe piles (16-, 24-, and 42-inch-(406-, 610- and 1067-mm-)diameter), filled with concrete and steel reinforcement. Deep penetrations required through layers of very dense/cemented sands in some locations, caused serious drivability and pile integrity concerns. The need for large pile driving hammers and large diameter steel pipe piles pushed the engineers and prospective contractors well beyond the limits of local experience. Such questions as the feasibility of driving the pipes closed-ended through dense upper strata, and quantifying the effects of installation on the long-term capacities of the piles, led CALTRANS to develop a comprehensive pile test program to address the design and construction issues effectively. The results were furnished to prospective bidders on the production stages of the ensuing contracts.

Jan 1, 1996

By J. P. Welsh

Ground Modification construction is rapidly evolving in the United States. An assessment of the construction status of Ground Modification methods with their dates of introduction and general acceptance in the United States is summarized. Seven of these techniques are discussed in depth with short case histories; namely, Dynamic Deep Compaction, vibro-compaction, vibro-Replacement, chemical grouting, compaction grouting, slurry grouting and jet grouting. Additional case histories are presented to illustrate the trend of combining Ground Modification techniques to solve specific site problems.

Jan 1, 2010

By M. D. Khattar

The paper describes the salient construction features of the Pile foundation work for the Railway viaducts in Algeria. Six viaducts were constructed for execution of the Railway line between Aintemouchent and Benisaf in Algeria. The work was executed by the Indian Railway Construction Company Limited of India (IRCON) for the Algerian National Railways (S.N.T.F.). These six viaducts had multiple spans of 36M resting on hollow piers of heights upto 69M. Most of the piers were founded on piles of 1 and 1.2M dia bored piles going upto 22M deep through cal­careous rocks and were designed for Railway loading in seismically active area. The work involved 356 piles & constituted a very important aspect of the whole work. The concrete in the piles was made with sulphate resistant cement and the integrity of the concrete was tested with Sonic method so as to ensure the quality. The piles were driven with the help of a hydraulic oscillator and the concrete was laid with a tremie pipe. Problems as encountered during execution have been explained.

Jan 1, 1989

By M. A. El-Sohby

The paper describes some problems encountered with the foundation of a deep drainage caisson constructed on the Nile Bank in Cairo. The use of suction dredging while sinking the caisson led to a piping failure of the sandy soil in the base which was loosened during the process of pumping. A study was carried out to investigate the problem and a procedure was adopted to retain the stability of the caisson.

Jan 1, 2010

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