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Technically speaking, the concept of NDT sounds like the "magic bullet" when faced with a questionable drilled shaft. All the Contractor or Engineer needs to do is select an NDT method, apply it, understand the details and extent of the defect and determine whether it will impact the load carrying capacity of the shaft during it’s design life. Unfortunately, it is not that simple. NDT is a tool utilized to indirectly assess the condition of the completed drilled shaft. For the most effective interpretation, NDT data should be correlated with the subsurface information, visual observation, and detailed shaft installation records. The basis for acceptance or rejection of drilled shafts should not be solely based on NDT. The parties responsible for specifying, interpreting and using the NDT results must understand the capabilities and limitations of the method to be utilized, in conjunction with the relevant subsurface conditions of the site, before selecting and specifying a system and acting on the results. This is necessary so that an appropriate NDT method can be specified and contracted. In this manner the results and roles of the responsible parties can be clearly defined.

Jan 1, 2004

By Osamu Taki

The innovative Soil-Cement Mixed Wall Technique emerged in Japan and obtained recognition in the engineering and construction communities in the 1980's. This technique was introduced to the United States in 1986. It was accepted as the most credible construction technique by the U.S. Bureau of Reclamation for ground stabilization and cutoff wall work in the Jackson Lake Dam Project, Wyoming in 1987 and 1988. It was also accepted as a remediation technique by U.S. EPA for a Superfund Innovative Technology Evaluation (SITE) demonstration on in-situ solidification/ stabilization. The Soil-Cement Mixed Wall Technique consists of mixing in-place soils with cement grout or other reagent slurries using multiple axis augers and mixing paddles to construct overlapped soil-cement columns. The overlapped column panel is then extended to form an underground continuous soil-cement wall for use as a cutoff wall or a structural diaphragm wall for groundwater control and excavation support. By arranging the column panels in various configurations, the technique becomes a versatile tool for stabilization of soft or liquefiable soils.

Jan 1, 1990

By William B. Conway

This paper will describe the large caisson pier foundations for four of the bridges crossing the Mississippi River in the New Orleans area; and will discuss some of the unusual problems encountered during their sinking. Certain settlement phenomena experienced during their service life will also be related: The four bridges in order of their construction: The Huey P. Long Bridge, River Mile 106.1, completed in 1935 The Greater New Orleans Bridge No.1, River Mile 96.0, completed in 1958 The Hale Boggs Bridge, River Mile 121.6, completed in 1983 The Greater New Orleans Bridge No.2, River Mile 96.1, completed in 1988 Each of these bridges employed large open-dredged concrete caissons as foundations for one or more of the river piers, with the smallest being the 65ft by 102ft caissons for Piers I and II of the Huey P. Long Bridge and the largest being the 99ft by 214ft caisson for Pier II of the Greater New Orleans Bridge No.2. The Huey P. Long caissons are founded in a dense fine sand at -170 while all of the other bridge caissons are founded in hard preconsolidated clay at elevations varying from -150 to -185. The Huey P. Long Bridge is currently being widened without increasing the caisson foundations under any of the river piers; and the design reasoning that led to this decision is presented.

May 11, 2007

By Krishna R. Reddy, Jyoti K. Chetri, Girish Kumar

Geotechnical engineering encompasses a major portion of the civil and infrastructure projects. The large amounts of energy and resources typically used in these projects leads to undesirable emissions and wastes which contribute substantially towards global environmental impacts (e.g., global climate change). This could further include secondary economic and societal issues which are often unaccounted in traditional engineering design of the geotechnical projects. In order to address this issue, it is imperative to integrate the broader environmental, economic and social implications into decisions of a geotechnical project. Recent years have seen a major impetus on life cycle assessment to evaluate the environmental sustainability of the geotechnical designs. However, there are no tools that can quantify the life cycle triple bottom line sustainability of potential design alternatives in a project with holistic considerations towards broader economic (indirect costs and benefits) and social impacts (stakeholder preferences, socio-environmental and socio-economic impacts). This study presents a new framework for quantitative assessment of life-cycle sustainability (QUALICS) for alternative designs in engineering projects. The framework integrates two multi-criteria decision analysis methods namely, the Integrated Value Model for Sustainable Assessment (MIVES) and Analytic Hierarchy Process (AHP), to support decision making on the potential design alternatives. In this study, a brief overview of the framework is presented. A case study demonstrating the use of QUALICS framework is discussed with its application to the sustainability assessment of two deep foundation systems, caissons and piles, over their design life. The technical designs of both systems are developed based on bearing capacity, both primary and secondary settlements, and structural integrity. The results from the sustainability assessment of the two deep foundation systems are discussed, and the most sustainable option based on different stakeholder preferences and site-specific conditions are identified.

Jan 1, 2019

By Richard Brink, Eric M. Klein, Kenneth B. Andromalos

"A portion of the roof for a 129 x 144-inch, nearly 100-year-old sewer outfall in the City of Baltimore had deteriorated to the point that it resulted in the development of a large sinkhole in a residential neighborhood. A subsequent video inspection of the sewer outfall indicated that there was a hole in the sewer outfall, and it would need to be repaired . After initial backfilling of the sinkhole and repairs to the water service lines, a conventional wood shoring system was used to support the excavation and expose the Main Outfall Sewer to inspect and repair it. This excavation was unsuccessful because of loose sandy soils and high groundwater conditions. An innovative use of a steel reinforced jet grout excavation support system was ultimately used to underpin an adjacent 20-inch water main and other nearby utilities, and provide access to the top of the Main Outfall Sewer some 22 feet below the street surface to facilitate inspection and repair of the sewer. This excavation support system was also successfully utilized in the final repair of the sewer roof by serving as a buttress for the new roof system.1.0 IntroductionThe project site is located in a residential neighborhood with brick masonry row houses situated on the south side of Chase Street and a brick masonry church on the north side of the street. Figure 1 illustrates the location of the site. The City right of way is 65 feet wide, and the street is 40 feet curb to curb. The centerline of the Main Outfall Sewer runs parallel to and a few feet south from the centerline of the street. Other utilities running parallel to the street include a cast iron 20-inch water line built about 1910, a 24-inch terra cotta storm drain, a 6-inch terra cotta sanitary sewer, a 4-inch cast iron gas line and a 40-inch electrical duct. Cross utilities included a 4-inch gas line and several smaller water and gas service lines to the church and row houses. One gas line that was not shown in the City's GIS database was exposed during the excavation."

Jan 1, 2005

By Yoshio Mitarai, Takeshi Nagatome, Yosuke Tanaka

"This paper describes an application of lightweight soil in a deep water area to stabilize an existing quay wall at the Port of Tokyo. Super Geo Material, abbreviated SGM, is a type of lightweight soil, which consists of dredged cohesive soil, cement and air foam, and is applied in coastal development work, such as port and airport construction. This paper reports a SGM construction project at the Port of Tokyo by using a SGM special plant vessel, which was deployed for the Tokyo International Airport (TIA) Expansion Project in order to achieve large-scale and rapid construction. The key issue in SGM construction is quality control. One key quality issue is control of the mix proportion of SGM in consideration of volumetric changes due to air foam-breaking during pumping and air foam shrinkage due to water pressure when SGM is placed in deep water. A smart technique for placing SGM is also necessary to prevent quality deterioration when SGM is placed in deep water, for example, increased bulk density and decreased shear strength due to water absorption. This paper introduces an actual case of SGM construction with a particular focus on quality control of SGM during construction.INTRODUCTIONSuper Geo Material, abbreviated SGM, is a lightweight stabilized soil which is used in coastal development work in Japan (CDIT 2008). SGM is applied as a backfilling material behind existing quaywalls or above underground structures in order to reduce earth pressure on the existing structure and improve seismic resistance. SGM has been applied in many coastal development projects. In particular, SGM was used at the Tokyo International Airport (TIA) Expansion Project (Haneda Airport) as the backfilling material at a quay wall at the joint between the reclaimed area and pier part in a new runway (Nagatome et al. 2010a & 2010b, Yamatoya et al. 2010, Mitarai et al. 2011). In this project, large-scale and rapid SGM construction was implemented by the special SGM plant vessels within 6 months under the condition of limited construction period.This paper introduces a new SGM construction project at the Port of Tokyo in 2011. This project employed the special SGM plant vessel, “Ryujin Mark II”, to achieve large-scale and rapid construction within a limited period. SGM was also placed in a deep water zone at the maximum water depth of approximately 15 m. Thus, quality control of SGM was a key issue for meeting project requirements. This paper describes the actual SGM construction in the Tokyo Bay area and quality control techniques for SGM, considering volume changes due to pumping and placement below water."

Jan 1, 2015

By Joel Moskowitz, Jan Cermak

"New York City has unique geologic conditions which must be considered when designing pile foundations. Where shallow foundations are not feasible, the City's subsurface conditions require a variety of deep foundation systems, ranging from high capacity rock socketed piles, to piles end-bearing on bedrock, to friction piles bearing in alluvial or glacial deposits. Pile load testing is essential in confirming pile capacities as pile analyses include assumptions on soil and soil-pile response, and pile driving equipment. Load test results must be interpreted to estimate the long-term pile behavior. Except for lightly loaded driven piles, the New York City Building Code (the Code) requires that pile capacities be confirmed by static load testing. The Code provides the number of static load tests required, test procedures, and acceptance criteria. In the last few decades, methods other than static load testing have been developed including dynamic and rapid (pseudo-static) load tests. Recently, those methods have also been employed on several projects in New York City. The traditional approach to pile load testing in New York City is discussed herein including engineering involved in the analyses of test data with examples. In addition, several projects which included non-static load testing are discussed INTRODUCTIONPile load testing complements the subsurface information and pile design by providing further data on pile-soil interaction for the selected pile type and installation method. Traditional approaches to pile load testing in New York City involve static load tests to verify the design capacity of the piles for a given minimum factor of safety.In the late 1950's, Dr. Phillip C. Rutledge summarized his views on the philosophy of pile foundations in an unpublished, in-house document. He viewed pile foundations as good illustrations of pertinent and impertinent aspects of geotechnical engineering. In the analyses of piles he divided engineering into four general types:(a) Theoretical engineering in which decisions are made based on theoretical analyses. This represents ideal engineering, in which all factors affecting the pile design are well established or, at least, few simplifying assumptions with known effects on the analyses are made."

Jan 1, 2005

By Bradley J. Fleming

Although soil improvement and its application to deep foundations is gaining popularity in the engineering community, this technique is not widely used in high seismic regions due to lack of fundamental understanding of both the behavior of improved soils under high-strain cyclic loading and the interactions between the pile, improved soil, and unimproved soil. This paper describes part of an ongoing Network for Earthquake Engineering Simulation (NEES) project, where two identical full-scale steel pipe piles were driven at a soft clay site in Oklahoma. The soil surrounding one of these piles was improved using the cement deep soil mixing technique in order to enhance its lateral load behavior. Both piles were tested for seismic resistance using dynamic and quasi-static loading. The pile in unimproved soil provided larger displacements with limited lateral force resistance. This pile was subjected to lateral displacements of up to 400 mm, but experienced minimum inelastic actions. On the other hand, the pile in improved soil reached its lateral capacity at a displacement of 100 mm, at which point the critical region at the base of the pile just above the improved ground experienced buckling and fractured due to low cycle fatigue. Compared to the pile in unimproved soil, the improved ground increased the system strength by 42%. Although the soil was improved over 2900 mm, the effective improvement depth was approximately 1300 mm below the ground surface. In this paper, it is demonstrated that the effects of block type soil improvement of limited horizontal and vertical dimensions can be described using a simplified theoretical approach involving a modification to the well-known p-y representation of soil response. An example using this method is presented and shown to give adequate support to a standard 12-inch diameter steel pipe pile embedded in soft soil.

By Masaki Kitazume

"Many earthquakes take place every year in Japan, in which the 1995 Hyogoken-Nambu earthquake and the 2011 Tohoku earthquake induced both a humanitarian crisis and massive economic impacts. As liquefaction which occur in a loose and saturated sand layer, induces quite large damages of infrastructures, the importance of liquefaction mitigation has been emphasized to minimize earthquake disasters for many years. Many kinds of ground improvement techniques based on various improvement principles have been developed for earthquake disaster mitigation. Among them, the grid type deep mixing method has been often applied to liquefaction mitigation. In the method, the stiff grid walls are constructed by mixing the soil and binder in-situ, which are expected to restrict the shear deformation of the soil within the grid walls so that the pore water pressure generation can be remained small. The high applicability of the method was confirmed in several earthquakes, including the 1995 Hyogoken-Nambu earthquake and the 2011 Tohoku earthquake. In this paper, the development of the method, some applications of the deep mixing method to earthquake disaster mitigation are briefly introduced. INTRODUCTION In Japan, many earthquakes take place every year in Japan, in which the 1995 Hyogoken-Nambu earthquake and the 2011 Tohoku earthquake induced both a humanitarian crisis and massive economic impacts. As liquefaction induces quite large damages, the importance of liquefaction mitigation has been emphasized to minimize earthquake disasters for many years. Table 1 shows the amount of damage to port facilities (Noda, 1991). According to the table, the amount of damage when liquefaction takes place is about 20 to 50 times larger than that without liquefaction. This highlights the importance of liquefaction mitigation to minimize earthquake disasters. There are many kinds of soil stabilization techniques developed for liquefaction in Japan. Among them, the deep mixing method (DMM), an in-situ cement stabilization techniques, was developed in 1970s in Japan and has frequently been applied to improvements of clayey and sandy soils (Kitazume and Terashi, 2013). The grid type DMM has been often applied to prevent liquefaction, where the grid of stabilized column walls function to restrict generation of excess pore pressure in the soil within the walls by confining the soil particle movement. The improvement effect of the method was first evaluated in the Hyogoken-Nambu earthquake in 1995 and was also evaluated in the Tohoku earthquake in 2011. In this paper, some successful performance of the deep mixing method to earthquake disaster mitigation in the two earthquakes are briefly introduced."

Jan 1, 2015

By Jin-Wei Huang, Bradley J. Fleming, Sri Sritharan

"Although soil improvement and its application to deep foundations is gaining popularity in the engineering community, this technique is not widely used in high seismic regions due to lack of fundamental understanding of both the behavior of improved soils under high-strain cyclic loading and the interactions between the pile, improved soil, and unimproved soil. This paper describes part of an ongoing Network for Earthquake Engineering Simulation (NEES) project, where two identical full-scale steel pipe piles were driven at a soft clay site in Oklahoma. The soil surrounding one of these piles was improved using the cement deep soil mixing technique in order to enhance its lateral load behavior. Both piles were tested for seismic resistance using dynamic and quasi-static loading.The pile in unimproved soil provided larger displacements with limited lateral force resistance. This pile was subjected to lateral displacements of up to 400 mm, but experienced minimum inelastic actions. On the other hand, the pile in improved soil reached its lateral capacity at a displacement of 100 mm, at which point the critical region at the base of the pile just above the improved ground experienced buckling and fractured due to low cycle fatigue. Compared to the pile in unimproved soil, the improved ground increased the system strength by 42%. Although the soil was improved over 2900 mm, the effective improvement depth was approximately 1300 mm below the ground surface.In this paper, it is demonstrated that the effects of block type soil improvement of limited horizontal and vertical dimensions can be described using a simplified theoretical approach involving a modification to the well-known p-y representation of soil response. An example using this method is presented and shown to give adequate support to a standard 12-inch diameter steel pipe pile embedded in soft soil,IntroductionPilings are the preferred foundation support for many civil engineering structures including highway bridges, railroad bridges, and port wharves. These structures and their foundations are subjected to forces created by earthquakes, wind, waves, water current, vessel impact, ice, and gravity. All loads applied to the superstructure must be transmitted to the foundation where they are resisted by the surrounding soil. With significant lateral loads, use of pile foundations may be the only solution to transmit large structural loads to competent soils. Piles supported by competent soils are relatively easy to design and costs are often attainable. However, thick layers of weak soils such as soft clays are widespread in high seismic areas (e.g., San Francisco, southern Nevada, Washington, Eastern Missouri, and Arkansas), exacerbating design challenges. Soft clays reduce the lateral resistance of the pile-soil system, making the pile foundation less cost effective. In this case, the current design practice is to use an increased number of larger diameter piles, which is a costly alternative (see SDC, Caltrans 2010). An innovative and more cost-efficient solution to this problem is to improve the soil within a short depth surrounding the foundation, thereby increasing its lateral stiffness. Some well-known methods for improving soil include deep soil mixing, stone columns, and simple soft soil replacement with select granular material."

Jan 1, 2017

By A. V. Rose

A redevelopment in the City of London has been constructed with a piled foundation system that is believed to be the first of its kind. The purpose of the research is to explore this novel foundation method, which involves the installation of closely spaced piles in a perimeter arrangement with a body of soil enclosed in the centre. Both centrifuge modelling and numerical modelling techniques are used.

Jan 1, 2011

By Anthony T. C. Goh, Zhiye Zhao, Laddu B. Jayasinghe, Hongyuan Zhou, Yilin Gui

"Ground vibrations from blasting are undesirable and they are very short in duration with high principal frequencies and high amplitude. Structural response to that kind of excitations may differ significantly from that generated by lower-frequency earthquake vibrations. In practice, the damage to nearby structures to generated ground vibrations has been controlled by various codes and regulations available. However, the existing vibrations limits are not always applicable, as they depend on the geological conditions of the site and the dynamic characteristics of the structure. This paper investigated the influence of the rock-soil interface on the response of pile foundation to ground-borne vibration from rock blasting, through numerical simulations using finite element software LS-DYNA. It is found that the slope of the rock-soil interface greatly influences the location of damage and the extent of damage on the pile. The bottom of the pile is subjected to a larger blast pressure and stresses are highly concentrated at the pile bottom. Thus, the pile bottom can fail in shear before it reaches its plastic moment capacity.INTRODUCTIONDrilling and blasting is the widely accepted method to large-scale rock breaking activities in civil engineering constructions due to its cost effectiveness, higher efficiency and ability to break hard rock. However, ground vibrations from blasting are undesirable and it can cause damage to nearby structures. In practice, the damage to nearby structures to generated ground vibrations has been controlled by various codes and regulations available. The existing vibration limits are not always applicable, as they depend on the geological conditions of the site and dynamic characteristics of the structure.Pile foundations are commonly used as foundations of high-rise buildings and bridges to transfer the heavy loads from the superstructure above through weak compressible soil strata into deeper, competent soil layers which have adequate capacity to carry these loads. In engineering practice, many piles are normally designed to carry mainly vertical loads and very little lateral loads, as typically the vertical loads (the gravity) are significantly larger than the horizontal loads such as wind loading. However, in recent years, there have been a number of reported case studies of translational soil movements that have induced stresses and bending moments that have damaged pile foundations and in some cases resulted in collapse of the superstructure. Typical lateral load include nearby construction activities such as an excavation for a basement or slope, the construction of a road embankment or a tunnel, as well as earthquakes (Abdoun 1997; Goh et al. 1997; 2003; Chen et al. 1999; Dobry et al. 2003; Boulanger et al. 2007; Black et al. 2007)."

Jan 1, 1900

By Andrew Z. Boeckelmann, David S. Graham, Paul J. Axtell

In the last fifteen years, several research studies have evaluated the ability to detect various types of deep foundation concrete integrity flaws with crosshole sonic logging (CSL) and thermal integrity profiling (TIP). This paper synthesizes the findings from the research, focusing on two studies that included CSL and TIP testing of drilled shafts with various types of flaws. The first, a 2016 research study of test shafts for the Wisconsin DOT, included inclusions inside and outside the reinforcing cage, intentional tremie withdrawal during concreting, and soft bottom flaws. The second, a 2021 study of production shafts for the Missouri DOT, included one shaft with and another without soft bottom conditions. After synthesizing the ability of each test method to detect each type of flaw, the paper presents recommendations for improving how CSL and TIP results are evaluated in practice. The recommendations highlight DFI‟s CSL interpretation protocol as well as the importance of evaluating TIP data versus time, not just depth. The paper includes example temperature-versus-time plots for various types of flaws and emphasizes how temperature-versus-time evaluation can be used to distinguish soft bottom conditions from standard bottom-of-shaft temperature roll off.

Oct 1, 2022

By Bo Westerberg, Mattias Andersson, Yvonne Rogbeck

"Deep stabilisation has been used in Sweden for decades. The method has been improved to allow it to be used in different types of soils and with new binders. One challenging soil type in Sweden is so-called sulphide soil, a fine-grained soil which contains organic material and iron sulphides. There have been some cases in Sweden of problems when using deep stabilisation in this type of soil, and in one case a slope failure occurred. This paper shows that it is possible to achieve good results with deep stabilisation in sulphide soils. Laboratory and field studies from a test site along the Botniabanan railway line in Sweden are presented. Geotechnical and chemical properties of the natural soil were investigated in the laboratory and one or more of these properties may explain the differences in the stabilising effect of sulphide soils. The strength of the laboratory samples and the columns in the field were tested and compared. It is shown that a satisfactory stabilisation effect can be achieved with the proper choice of binder, amount of binder added, curing time and mixing energy. In sulphide soils, more binder additive is needed than in “ordinary” inorganic clays.1. INTRODUCTIONThe term sulphide soils is used in this paper to refer to the unique types of sulphide soil commonly found in the coastal areas along the north-eastern coastline of Sweden between the cities of Gävle and Haparanda, a distance of about 900 km. Sulphide soils are in general very compressible, susceptible to creep deformation and normally show low undrained shear strength. A sulphide soil may have a negative environmental impact through acidification and chemical action if it is subjected to oxygen, for example during excavation or lowering of the ground water table, Mácsik (1999). In foundation engineering works, efforts are made, for environmental or/and economic reasons, to use the sulphide soil as the foundation instead of excavating it. Deep stabilisation by means of columns is a potential method for use when sulphide soil needs to be improved in order to reduce settlements or/and increase the stability of embankments.Sulphide soils were formed as sediments at river mouths and off the coast in the special environment prevailing at the time of sedimentation, Mácsik (1994). The water in which the sulphide soil was sedimented was brackish/sweet and the environment was typically deficient in oxygen. The environment prevented complete decomposition of the organic material in the sediments. As a result, sulphide soils were formed primarily in the form of a fine-grained composition of clay and silt minerals, iron sulphides and organic matter. Such environments still exist today and new sulphide soil sediments continue to be formed."

Jan 1, 2015

By Gilbert Chuah, Peter Middendorp, Joost Bakker, Soon-Hoe Chew

"The Rapid Load Testing (RLT) of foundation piles has been applied worldwide since 1984. Several International and national codes are available, such as the Japanese Code of Practice (2002), ASTM D7383-2010, German recommendation on Piling (2012) and Eurocode (2015). RLT methods like Statnamic and StatRapid are gaining popularity in Asia, Europe and North America. For checking the performance of piles, they are more economical, faster and environmentally friendly than Static Load Testing (SLT), while yielding good correlations with SLT results through an objective analysis method. To date (October 2016) hundreds of piles have been successfully tested by RLT method in Singapore. A number of these RLT tests were coupled with static load testing correlation tests, some of them with instrumentation for shaft load transferred. Examples of some correlation results for foundations installed in various geological formations in Singapore are presented in the paper. The findings from these results indicate that loading rate effects are negligible for Rapid Load Test results when foundations are socketed in competent non-cohesive soil layers and derive most of their capacity from these soil layers.INTRODUCTIONRapid Load Testing (RLT), by which a quasi-static load is applied to a foundation pile, is used increasingly as an alternative to Static Load Testing (SLT) for cast in-situ piles, such as drilled shafts or bored piles. It is recognized nowadays that the determination of the pile capacity with Dynamic Load Testing (DLT) through signal matching techniques such as CAPWAP, TNOWAVE and AllWave-DLT, yield a wide spread of results for cast in-situ piles (Stahlmann et. al, 2012), making it practically very difficult, if not impossible to calibrate the DLT results with SLT results. This spread is due to the empirical and subjective assumptions that are used to interpret the test data, especially for cast insitu piles (Holeyman et al. 2001, Viana da Fonseca in 2008, Herten et al, 2013). This is further complicated by the inhomogeneity of the concrete and variable cross-sections over the pile length for the cast in-situ piles."

Jan 1, 1900

By Frank Rausche

Why testing What tests can be done Dynamic load testing Loading device Measurements Analysis Examples

Jan 1, 2001

By Gerald Verbeek, Erick Baziw

Dynamic soil analysis (DSA) in geotechnical practice is intimately related to the capability of measuring the necessary soil properties of shear modulus and absorption. In DSA the methods of analysis are based upon the stress-deformation response of soils due to imposed shear strains. Typically the soil profile is numerically modeled as linear visco-elastic system. This technique is referred to as the Equivalent Linear (EL) method, and it requires the specification of the input parameters of low-strain (<10-5) shear modulus, modulus reduction, and the equivalent viscous damping ratio, which is directly related to the soil absorption value. Downhole seismic testing (DST) has proven to be a very accurate tool for estimating low strain shear modulus values as long as source wave raypaths are taken into account, especially for near-surface investigations. DST has also been utilized to estimate low-strain interval absorption values. In these cases standard frequency domain absorption estimation algorithms (such as the spectral ratio technique) are utilized where it is assumed that the source waves are traveling along the same travel path, which is obviously not the case for near surface DST investigations. This paper outlines a unique DST absorption estimation methodology, which is carried out in the time domain and takes into account source wave travel paths. 1. INTRODUCTION There is considerable interest in methods of geotechnical in-situ engineering that provide accurate estimates of the shear wave velocity and the associated absorption values in the ground, since these parameters form the core of mathematical theorems to describe the elasticity/plasticity of soils and they are used to predict the soil response (settlement, liquefaction or failure) to imposed loads (whether from foundations, heavy equipment, earthquakes or explosions).

Jan 1, 2019

By Abu B. Siddique, Anthony S. Crincoli

"The New Jersey Turnpike Section 2 widening program consisted of widening between Interchange 6 in Mansfield Township, Burlington County and Interchange 9 in East Brunswick Township, Middlesex County. To accommodate large volume of traffic the roadway was widened from 6 to 12 lanes with major modifications performed at four interchanges. The Section 2, NJTA Interchange 6 to 9 Widening Program is a 4.2-mile section of Turnpike roadway which included a total of 12 new or modified structures. In order to facilitate the construction process Section 2 was divided into three construction contract packages. This paper will cover the last and final Contract T869.120.203 which is 1.7 miles in length. The work generally consisted of eight new ramps connection to and from the toll plaza to the new inner and outer roadways. New mainline bridges were constructed over several ramps. A new bridge was constructed to take northbound outer lanes traffic over two ramps along with new mainline bridges over Black’s Creek, Georgetown Road, and Laurel Run. In addition, a new bridge was constructed to take a ramp over Laurel Run and the existing U-turn Bridge was replaced with a new one.For Contract T869.120.203 a total of 74 five-foot diameter drilled shafts has been constructed to support all pier foundations for bridges. Three drilled shafts were tested using Osterberg Load Cells to verify the estimated shaft resistance during design phase. One Osterberg Load Cell test was performed on a demonstration (sacrificial) shaft and the other two Osterberg Load Cell tests were performed on production shafts. This paper compares the estimated total, side and tip resistances with corresponding measured total, side and tip resistances and provided recommendations for future design purpose.INTRODUCTIONTo accommodate large volume of traffic the New Jersey Turnpike Authority (NJTA) decided to widen Section 2, which included Interchange 6 through Interchange 9. The Section 2, a 4.2-mile section of Turnpike roadway that was widened from 6 to 12 lanes with major modifications performed at four interchanges.The New Jersey Turnpike Authority (NJTA) procured AECOM to perform engineering services for the final design of Section 2, NJTA Interchange 6 to 9 Widening Program. Section 2 is a 4.2-mile section of Turnpike roadway that will widen from 6 to 12 lanes and will include a total of 12 new or modified structures. It encompasses modifications of the existing and the design of four new ramps at Interchange 7. The project also includes the modification of two local roads over the mainline, two local roads under the mainline, two maintenance U-turns, and retaining walls. In addition, the project consists of the design of noise walls, sign structures, storm water management basins and the more typical drainage, utilities, lighting, roadway, ROW, and signing and striping design."

Jan 1, 2015

It is my great pleasure as mayor of the city of Amsterdam to welcome you today to Amsterdam, and to the 10th International Conference on Piling and Deep Foundations. The history of Amsterdam has been connected intimately with your professions of geo-engineering and geotechnology, since its very first days. It is good to be aware that you are part of a very old tradition. The knowledge that we need today to build and renew the city has been gathered over a century long process so that we fortunately can stand on the shoulders of the giants before us. During the centuries people living in this part of the Netherlands have always struggled against the water. The same waters that brought the opportunity for a seafaring country to discover the world and to build an empire in the 17th century were a threat to the low lying Netherlands.

Jan 1, 2006

By Edmund Cardoza

In the spring of 1993, construction began on an ambitious building project in Boston, Massachusetts. The Shriners organization committed to offer state-of-the-art adolescent burn treatment and rehabilitation in its Boston facility by expanding in a most unusual way. In short, the concept included installation of caisson foundations and perimeter slurry wall panels to enable construction of a completely independent structure around and above the existing, continually functioning, hospital. Two distinct phases of work were detailed in the Contract Documents. At the completion of the first phase, patients will be moved into the new building, above, and demolition of the old structure, beneath, will be performed. In Phase I, sections of the slurry wall and caissons, located outside the footprint of the existing building, were planned. The next phase of the work includes the installation of the remaining caissons and slurry wall. Once excavation is completed, the balance of the new hospital structure will be constructed from the bottom upward, connecting to the under side of the new structure.

Jan 1, 1994