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By Jerold Bishop

The application of the ?electro-hydrodynamic effect? (EHDE) to civil engineering has been made in the construction of drilled piles. Equipment for the commercial application of this process was developed in Russia in the late 1980's. The process is approved for general use by the Russian Federation building code and numerous projects have been successfully completed with this technique. EHDE is a process by which a moderately powerful shockwave is released in the bottom of a drill hole filled wet concrete slurry. The energy is carried outward through the fluid with minimal loss because it is an incompressible medium. Repetitive discharges provides a series of energy pulses which will compact the soil along the pile shaft and at base of the pile. The process is analogous to repeated applications of low energy blast densification or to dynamic compaction. In general, the process is not depth dependent. Repeated application of this treatment in a drilled pile hole can increase soil density at the base and along the shaft of the pile, as desired. The overall result is that the geotechnical capacity can be improved significantly. Test results documenting improvements are presented and other applications considered.

Jan 1, 2007

By Nagarajan. D, Raja Rajan. K, Vijayakumar. T

Major bridges crossing mighty rivers must be constructed in flowing water. Constructing the sub-structure in water has been a challenging job for contractor. Special construction techniques with marine fleets to be adopted for waterfront construction. Enabling works like temporary piling platform and cofferdam used for pile and pile cap construction. Apart from this, enabling works like load out jetty to transport the materials from land to water; temporary walkway for access of workman to work location; temporary access bridge for construction vehicles movement; temporary liners for tower crane foundation; Concrete block to act as dead man anchor for barge movements were all required by the contractor for smooth functioning of site as per construction schedule. Investment in enabling works by contractor plays a significant role on profit margin of the project and of course with utmost safety. Design of enabling works for waterfront structures involves hydrological data like afflux, bathymetry survey, current force, scour depth and wave force to be taken cautiously for safe and economic design. Type of foundation and pile/well cap top level corresponding to water levels shall influence the construction scheme. Usage of geotechnical software like Wallap and Plaxis required for enabling work design to enhance the safety of the structure. Bathymetry and soil condition play a critical role in design and construction of enabling works. Water Discharge quantity in river along with water levels like low water level, high flood level, seasonal fluctuation of water levels has a great impact on design of enabling works. Establishing enabling works for waterfront construction near to an existing bridge is an additional challenge for the contractor. Along with design, constructing the enabling works in water requires special construction methodology and sequence of work. This paper shall provide insights on overview of design and construction of enabling works for waterfront construction.

Nov 1, 2022

By Andrew Baxter

This paper focuses on the design of steel bearing plates to transfer load from tiebacks and tiedowns to a concrete mass. It lists and describes the various available procedures for design of bearing plates as well as explains the design procedure recommended by the authors, which incorporates the Post Tensioning Institute (PTI) recommendations. The paper includes a step-by-step design example following the recommended procedure that captures the most important aspects of plate design. The dimensions of the plate calculated from this example are compared to the design dimensions obtained from various other procedures, including those by American Association of State Highway and Transportation Officials (AASHTO) and VSL International, Ltd. (VSL). The paper also includes the results of numerical modeling of the plate that will help the reader understand important aspects of plate-concrete interaction. The authors envision that this paper will serve to create an understanding in the geo-industry of suitable design methods and help improve procurement of bearing plates for tiebacks and tiedowns.

By V K. Panwar, Sampat Raj

At a Fertilizer plant located in the southern part of India, 74 numbers of pump foundations have shown non-uniform settlements causing the tilting of pump foundations under self-weight primarily due to the presence of varying thickness of the heterogeneous subsoil beneath the pump foundations and soil erosion because of water seepage through deeper excavations in the close vicinity. Various corrective measures have been explored and taking due cognizance of the prevailing subsoil conditions, site constraints, and constructability aspects, micropiling has been adopted. This paper presents the site problem and details of remedial measures adopted for rehabilitation of the distressed pump foundations. The main objective of this paper is to provide guidelines for designer during design and detail engineering stage to avoid similar nature of problems and also to provide a solution concept to tackle similar nature of problem(s) if encountered at site.

Nov 1, 2022

By Les R. Chernauskas

? What is Integrity Testing? ? Cross-Hole Sonic Logging (CSL) ? Single-Hole Sonic Logging (SSL) ? Typical Specifications ? Case Histories ? Observations and Conclusions WHAT IS INTEGRITY TESTING? General Definition ? Process in which the condition or structural makeup of an object can be evaluated with respect to defects such as a reduction in cross section (void or crack) or reduction in material strength (water, slurry, soil mixed with concrete). ? If the defect is severe enough, it can reduce or alter the load carrying ability of the object.

Jan 1, 2001

By H. Shiri

Iran's largest natural gas field is South Pars, geologically an extension of Qatar's 900-Tcf North Field. South Pars was first identified in 1988 and originally appraised at 128 Tcf in the early 1990s. This Field contains 38.6 % of the gas resources of Iran and is regarded as the largest offshore gas field in the world. Offshore geotechnical site investigations are one of the key activities of upstream fields operators to supply the EPC contractors with the required results for designing approaches of offshore complexes. In the mean time a lot of marine site investigations have been carried into execution within the phases of South Pars development. The authors are currently trying to create the fundamentals of investigating the small- and large-scale spatial variability of the South Pars Gas Field in Persian Gulf/ IRAN. Part of this investigation is the providing of an extensive data base of the offshore geotechnical properties of South Pars. Such a data base, will enable a model to be developed of the large-scale variability of these properties. In addition, this data set will provide a data whereby general trends to be established, as well as, providing relationships between geotechnical parameters and spatial parameters utilizing probabilistic and data mining methods like ANN (Artificial Neural Network) in Geotechnical Engineering.

Jan 1, 2006

By Bartho J. Admiraal

"As part of the Schiphol-Amsterdam-Almere project, the largest aqueduct in Europe is being built in order for the A1 motorway to cross the Vecht River. The A1 consists of 12 lanes and the total width of the aqueduct will be 65 m (213 ft). The total length of the structure will be 620 m (2035 ft). Speed of construction is essential for the DBFM-contract, which forms the primary reason for choosing a building method with a horizontal water retaining barrier created by low pressure grouting. After final checks on the water tightness of the silica based layer (softgel), excavation to a depth of approximately 12 m (40 ft) below the water table could be started in order to build the aqueduct.This paper presents a new approach for the calculation of the required grout volumes needed to ensure a “softgel” layer without gaps or holes. The approach applies measurement of deviations due to execution aspects in a probabilistic model. With this model, one is able to study the effects in a field application, i.e. multiple rows of grouted spheres. The results are visualized in order to analyze the risk of holes more easily. It is evident that the existence of a hole means a major leakage. By completing multiple runs, the strategy for grout volumes can be adjusted to minimize this risk.INTRODUCTIONThe Dutch Department of Waterways and Public Works invests over € 4 billion between 2012-2020 to increase the capacity of 63 km (41 mi) motorways of one of Holland’s major corridors. The A1/A6 will be transformed over a distance of 20 kilometers (13 mi). Near Muiden, the current drawbridge on the A1 for crossing the Vecht river will be replaced by a new aqueduct to be located slightly south of the existing bridge."

Jan 1, 2016

By A. B. Cerato, M. K. ElSawy, A. Elgamal

"Helical piles are gaining popularity as foundations for new construction as well as retrofitting option for deficient foundations. More recently, large diameter helical piles are used to support structures in regions characterized with high seismic hazard. Even though they have proven to be viable in seismic areas such as New Zealand, where they experienced little damage during the Christchurch earthquake, the knowledge about their seismic analysis and performance is largely lacking. Therefore, there is a need for comprehensive study to evaluate their performance under seismic loading. The current objective of this study is to investigate the performance of helical piles through a full-scale testing program that was performed at the NEES/UCSD Large High Performance Outdoor Shake Table (LLHPOST). The experimental setup involved ten steel piles of different configurations installed in dry sand. The piles were loaded with different masses and were subjected to different earthquake signals to simulate different dynamic behavior. This paper compares the performance of different moment curve fitting methods used to interpret the test data. Furthermore, the effects of different frequency content of loading on the pile response is illustrated in terms of deflection along the shafts of tested piles with different configurations.INTRODUCTIONEarthquakes are a major hazard for structures situated in seismic regions, and dynamic loading must be a design consideration. Successful design of a foundation system entails providing a safe and economic foundation solution to resist earthquake loading. Different foundation options have been used to support buildings in high seismic regions. Helical piles represent a viable foundation option that offers several advantages in terms of ease of installation, lower cost and environmental impact, ability to approximate the axial capacity directly from torque readings and more (Perko 2009). However, they are not typically considered as an option in many seismic regions. Meanwhile, several buildings supported on helical piles in New Zealand have survived the Christchurch earthquake with negligible damage, which encourages performing further research to understand the behaviour of these piles under seismic loading.A helical pile consists of a steel shaft fitted with a steel helix/helices. The helical pile is installed by applying torque to its head via mechanical torque. Nowadays, helical piles are used in a wide range of applications such as foundations for light posts and residential houses. The static behaviour of helical piles has been studied extensively and is relatively well understood (Tsuha and Aoki 2010; Mittal et al. 2010; Sakr 2011; Elsherbiny and El Naggar 2013; El Sharnouby and El Naggar 2012; Elkasabgy and El Naggar 2015; Weidong et al. 2015 and Bagheri and Naggar 2015) However, the dynamic and seismic behaviours of helical piles is seldom investigated (Elkasabgy and El Naggar 2013). This underscores the knowledge gap currently present regarding the seismic behaviour of helical piles."

Jan 1, 2017

By Aaron L. Sacks, David R. Good, Srinivas Yennamanda, Joseph K. Carey

Construction of Parcels 6 and 7, the second phase of The Wharf, began in 2019 and geotechnical construction was completed by December 2020. The overall project consisted of horizontal site, parks, and office buildings. The Wharf’s Phase 2 development includes approximately 1.2 million ft2 (110,000 m2) of above-grade construction including five multi-story, mixed-use buildings constructed over up to three levels of underground parking. The site is located between the WMATA Green Line Tunnels to the north and the Washington Channel to the south; it is bisected by a 108-in. (2740-mm) diameter DC Water outfall pipe. This arrangement, along with very difficult ground conditions, created challenges in the geotechnical design and construction. The support of excavation for this complex project required several different methodologies, including sheet piles, soldier piles, displacement piles, tiebacks, deep foundation anchors, jet grouting, and internal bracing with multi-tier rakers. Ground improvement was also required for support of spread footings in soft soils over the garage footprint. Underpinning of the active 108-in. (2740-mm) diameter DC Water outfall pipe running on a north/south alignment through the center of the site between the two garage structures was also performed. Since portions of the support of excavation are below the groundwater table, an extensive pre-excavation dewatering program was necessary and was separate from the foundation package. On the north side of the project, support of excavation (SOE) was required on a curved alignment, offset approximately 10 ft (3 m) from the outbound Green Line tunnel. Due to the proximity of the tunnel, a stiff, near-zero displacement wall was required. A portion of the buildings extend over the tunnels, imparting load to the tunnels to approximately restore original overburden loads excavated for the basement space. The building foundation is a 3 to 4-ft (0.9 to 1.2-m) thick mat slab anchored into the Potomac clay formation. Continuous movement monitoring of the tunnels was performed by an automated system. This paper describes the design and construction of the SOE and foundations for this high-profile project, which required collaboration between the Owner, Engineer, Construction Manager, and Specialty Geotechnical Contractor to solve many challenges.

Oct 1, 2022

By Steven D. Scherer

The highest earthquake risk in the United States east of the Rockies is along the New Madrid Fault System, which extends for 193 km (120 miles) through the Central Mississippi Valley from northeastern Arkansas, through southwestern Missouri, western Tennessee and western Kentucky to southern Illinois. Historically, this fault has generated some of the most powerful earthquakes in U.S. history, notably three Magnitude 8 events in 1811. Apart from the West Coast, this region experiences more earthquakes than anywhere else in the United States, with more than 200 events recorded along the fault annually. These events are typically of much lower magnitude than those experienced in California. Most are too small to be felt. However, should a significant event occur, damage can be expected to be widespread because of the underlying geology. In recent years, earthquake preparedness and seismic upgrade of vulnerable structures has become a focus for a number of State Departments of Transportation, including those in Illinois and Missouri where there is a potential for future damage. This paper presents three case histories illustrating three different techniques used to retrofit interstate highway bridge foundations bearing on potentially liquefiable soils. Friction minipiles were installed at the approach span of the I-57 bridge crossing the Mississippi River near Cairo, Illinois to provide additional support to the pile caps in the event of liquefaction of the underlying sands during a seismic event. In St Louis, Missouri, rock-socketed minipiles were installed to increase the capacity of drilled shaft foundations supporting a section of Interstate 64. In Mounds, Illinois, compaction grouting was used to densify loose sand deposits beneath a pile-supported interstate bridge on I-57.

Jan 1, 2001

By Arash Saeidi-Rashk-Olia, Dunja Peric

Energy piles are gaining increased popularity due to a growing demand for clean energy. To further advance the understanding of soil-structure interaction in energy piles, recently-derived analytical solutions have been implemented to investigate the impact of stratigraphy on the soil-structure interaction. This was accomplished by comparing the measured and predicted head displacements, axial strains and stresses in an energy pile embedded in the actual homogeneous and layered soil profiles, as well as into synthetic homogeneous soil profiles. The analytical solutions for homogeneous soil profile captured the smooth experimentally observed response versus depth very well. In the case of a layered soil profile, the corresponding analytical model was capable of capturing nuances in trends of axial stress and strain versus depth at the interface of different layers. The analytical predictions for the layered profile appear to be slightly less accurate than for the homogenous profile. The experimental data obtained from the layered profile appear to be a bit more scattered than those from the homogeneous profile. In the former case, the interplay of the individual soil layers with the pile occurs while maintaining the continuity of the pile stress and displacement at the interface of different layers. The response throughout each layer of the layered profile is quantitatively different than the corresponding homogeneous response. Nevertheless, qualitatively the response throughout each layer of the layered profile is similar to the response of the pile embedded in the corresponding homogeneous layer.

Sep 8, 2021

By Lance Helwirg

New high and low double outfall bridge structures for a juvenile fish bypass system have been constructed on the Washington Shore approximately two miles downstream from the Bonneville Dam on the Columbia River. The high and low outfalls each extend approximately 400 feet into the river from the Washington shore and are designed to release juvenile salmon into the river at above-water discharge elevations for improved survival rates. The two outfall structures include post-tensioned concrete double box flume girders approximately 7 feet high by 13 feet wide, which will be submerged in river flows as high as 15 feet per second. Each of the 6 offshore foundation piers is composed of a single 10-foot diameter reinforced concrete drilled shaft with a permanent steel casing embedded into the river bottom approximately 100 feet. Challenging outfall design conditions included designing the entire structures to be submerged for long periods of time in 15-feet-per-second river water flow with a 60-foot cantilever at the end of each outfall, and with the superstructure 70 to 80 feet above the river bottom. Figures 1-1,1-2, and 1-3 show the high and low outfall structure overhead photos and elevation view.

Jan 1, 2001

By John D. Thornley

Alaskan villages typically store a one-year supply of fuel to reduce significant delivery costs. Alaska Village Electric Cooperative (AVEC), an electric utility cooperative providing power to 51 Alaska villages, has made a concerted effort to upgrade and improve their undersized and aging facilities. The Village of Stebbins, located south of Nome on Norton Sound is receiving upgrades to its AVEC bulk fuel facilities. Stebbins offered unique challenges from a foundations perspective due to the nature of the soil. The geotechnical investigation found the soil below roughly a third of the footprint of the bulk fuel facility to be thawed with seasonal freezing and the remainder was found to be warm permafrost with ground temperatures of between 30°F and 32°F. This is a unique and challenging arctic engineering design issue because foundations are designed differently for frozen ground conditions. Driven piles were selected because of site constraints, such as the design flood elevation and the change from thawed to frozen ground conditions. The pile design specified that the pile embedment depths would be selected based on the results of pile driving analyzer (PDA) testing during construction in the thawed ground and maintained within the frozen ground portion of the footprint. Difficulties during pile driving in the frozen ground resulted in several piles becoming severely damaged, requiring subsequent removal. This resulted in a reevaluation of the means and methods for pile installation. Additional fieldwork was performed to further characterize the subsurface soils and their frozen nature. Options for installation of piles in difficult areas were evaluated including ground thawing, predrilling, and reducing embedment depths. Presented within this paper are the findings from the initial and subsequent field explorations, discussion of the design methodology, and the decisions that led to successful installation of piles at this challenging remote village.

By John D. Thornley

Alaskan villages typically store a one-year supply of fuel to reduce significant delivery costs. Alaska Village Electric Cooperative (AVEC), an electric utility cooperative providing power to 51 Alaska villages, has made a concerted effort to upgrade and improve their undersized and aging facilities. The Village of Stebbins, located south of Nome on Norton Sound is receiving upgrades to its AVEC bulk fuel facilities. Stebbins offered unique challenges from a foundations perspective due to the nature of the soil. The geotechnical investigation found the soil below roughly a third of the footprint of the bulk fuel facility to be thawed with seasonal freezing and the remainder was found to be warm permafrost with ground temperatures of between 30°F and 32°F. This is a unique and challenging arctic engineering design issue because foundations are designed differently for frozen ground conditions. Driven piles were selected because of site constraints, such as the design flood elevation and the change from thawed to frozen ground conditions. The pile design specified that the pile embedment depths would be selected based on the results of pile driving analyzer (PDA) testing during construction in the thawed ground and maintained within the frozen ground portion of the footprint. Difficulties during pile driving in the frozen ground resulted in several piles becoming severely damaged, requiring subsequent removal. This resulted in a reevaluation of the means and methods for pile installation. Additional fieldwork was performed to further characterize the subsurface soils and their frozen nature. Options for installation of piles in difficult areas were evaluated including ground thawing, predrilling, and reducing embedment depths. Presented within this paper are the findings from the initial and subsequent field explorations, discussion of the design methodology, and the decisions that led to successful installation of piles at this challenging remote village.

Jan 1, 2017

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 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 Jun Ohbayashi, Yoshiyuki Yagiura, Hiroaki Miyatake, Masuo Kondoh, Naotoshi Shinkawa

"Reducing the improvement ratio of ground improvement is an extremely efficient way to reduce the construction cost and construction period of mitigation measures for soft ground. The Arch Action Low Improvement Ratio Cement Column (ALiCC Method) is one method for this, and it is being increasingly applied to sites. This method enables us to rationally evaluate the embankment loads that are acting on cement improved soil columns and unimproved ground, by considering the arch action generated in the embankments and from there thusly allocate improved soil columns in spans of a greater distance than those needed for conventional methods. As a result, it serves to reduce construction costs and the construction period, while also minimizing the settling of the embankment and differential settlement, by placing numerous improved soil columns in the ground immediately beneath the embankment at equidistant intervals. In this report, we give a basic overview of the ALiCC Method, report typical construction results from real life cases that have been carried out, and make comparisons with other construction methods in order to report on the effectiveness of this design method.OVERVIEW OF ARCH ACTION LOW IMPROVEMENT RATIO CEMENT COLUMN (ALiCC) METHODIn the area of mitigation measures for soft ground, a significant role is played by ground improvements using improved materials such as cement. For this reason, a reduction in construction costs and construction period required for ground improvements has become of greater importance. The Public Works Research Institute carried out joint research with Kiso-Jiban Consultants Co. Ltd., Kitac Co. Ltd., and Fudo Tetra Co. Ltd. over a period from 1998 through 2002, and, from that, developed the ""Arch Action Low Improvement Ratio Cement Column Method"" (hereinafter referred to as the ""ALiCC Method"") that enables ground improvement with a lower improvement ratio (the improved area ratio is approx. 10% to 30%) than is required for conventional methods, while also ensuring stabilization and minimizing the settling of embankments.In the area of mitigation methods for soft ground by deep mixing, the dominant method until now has been that (50% or more of improvement ratio) shown in Fig. 1. This method comprehensively improves the area under the face of the slopes of both sides of the embankment. This is based on the calculated stability against rotational slip, which states, ""the most effective way to ensure the stabilization of the embankment environment is to carry out improvements of the area under the face of the slope."" Therefore, for the area under the face of the slope, ground improvement by deep mixing was done, and for the soft ground in the area under the middle part of the embankment, accelerated consolidation methods (hereinafter referred to as ""conventional method"") such as sand draining method and paper draining method were used. Mitigation measures that combine these improvement methods have also been mainstream for a long period of time and are used to prevent side deformation around the embankment. However, there have been some problems that have occurred, such as a situation where consolidation settling occurs in the center area under the embankment where no improvement had been carried out. This phenomenon leads to a situation in which the improved soil columns in the area under the face the of slope are pushed to the outside, which results in side deformation occurring around the area of the embankment, and additionally the occurrence of a step due to a situation of differential settlement between the improved ground and the consolidation advancing part, which results in cracks in the embankment."

Jan 1, 2015

By Cheng Lin, Guoming Lin

"This paper presents a case history for the design, construction and long-term performance monitoring of a driven prestressed concrete (PSC) piled foundation supporting a large liquefied natural gas (LNG) tank in Savannah, Georgia, USA. Following a geotechnical investigation, a design stage pile test program was performed with three objectives: to study the densification effect from pile driving on the liquefaction resistance, to test axial and lateral pile capacities, and pile behavior under lateral loads. The test program comprised five piles driven on a test pad constructed adjacent to the tank foundation. Cone penetration testing (CPT) was performed before and after pile installation to test soil densification effects from the pile driving and liquefaction potential was re-evaluated based on the soil densities after pile installation. The axial load tests involved static load testing, high strain dynamic testing, and Statnamic testing. This paper presents the findings of the densification effects, compares results from different axial testing methods and discusses the procedures to use the load test results in the pile design. The paper also comments on the construction issues and presents performance data with 10 years of monitoring.1. IntroductionThe project site is located at the Kinder Morgan’s Elba Island LNG Terminal on the Savannah River which is three miles downstream of the downtown Savannah, Georgia. This LNG terminal was initially developed in the 1970s as an LNG import terminal. The facility includes five LNG storage tanks with two larger tanks which were constructed in 2003 and 2006, respectively. The terminal is currently being converted into a liquefaction and export facility. This paper discusses pile foundations for Tank D4 which is a double walled insulated steel tank built to hold one million barrels of LNG in 2003. This tank has an outer tank diameter of 258 feet, an inner diameter of 252 feet, and liquid height of 113 feet. A number of geotechnical challenges were present in the foundation design and construction.??The site is a typical coastal deposit site featuring a thick layer of very soft under-consolidated clay (up to 40 feet in thickness);??The bedrock is a couple of thousand feet deep;??There is a sand layer that is liquefiable under a high seismic design category (0.5% possibility of exceedance in 50 years)."

Jan 1, 1900

By Schmitz Stefan, Stephan Jee-Sun

"Due to the reunion of Western and Eastern Germany in the late 80’s, a multitude of infrastructure projects had to be executed. A good portion of these projects required improvement of the motorway system. In the southern region of Leipzig, in the eastern part of Germany, it was required to connect two existing motorways. Parts of the new motorway pass old strip mining areas. These strip mining areas consist of up to 70m thick backfill material. Especially the upper 20m are very inhomogeneous soil material with a very low bearing capacity. In order to increase the bearing capacity, to decrease the differential settlements and to homogenize the soil parameters, soil improvement using sand-gravel columns was required. Bauer Spezialtiefbau GmbH executed the installation of approx. 711,000 linear meters of columns with a length from 5 m to 25 m. For the project, 11 rigs with frame leads up to 40m were used to install the 43,000 columns with a diameter of 0.8m in 27 weeks.1. INTRODUCTION1.1 Site LocationThe construction site is located in the south-eastern part of Germany, in the south west of the city Leipzig.The area to be treated had a size of approx. 500,000 m² to allow the construction of dam/embankments and a highway bridge.1.2 Required WorkIn addition to the general earthworks and the installation of geogrids and fibre mats, a total amount of more than 710,000 linm of Gravel-Sand Columns with different lengths due to the given soil conditions had to be installed:•nos. 4,206 Columns length 5m ? 21,030 linm•nos. 4,581 Columns length 10m ? 45,810 linm•nos. 10,820 Columns length 15m ? 162,300 linm•nos. 19,634 Columns length 20m ? 392,680 linm•nos. 3,574 Columns length 25m ? 89,350 linmFor the installation of the columns Gravel-Sand with the grain size of 0/32mm was used. The total amount of Material was 580,000mt"

Jan 1, 2015

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