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By Keith MacKay, John Carter, David Siddle, Fernando Faminia

"The River Green Residential development, is located in the municipality of Richmond, BC adjacent to the Fraser River. Ground conditions at the site consisted of medium to fine grained alluvial sands and a high groundwater elevation. A temporary low permeability retaining wall was required in order to facilitate the construction of an underground parking structure without inducing settlement of adjacent structures, which include the Richmond Olympic Oval; part of the legacy of the Vancouver 2010 Winter Olympics. Golder Associates Ltd. and GeoPacific Consultants Ltd. utilized Cutter Soil Mixing (CSM) technology to enable construction of a continuous combined low permeability cut-off and retaining wall around the perimeter of the property. The 350m long wall was keyed into marine clay at a depth of 28m below ground surface, and contained H-Pile reinforcement installed at regular intervals. The CSM technology provided many benefits for this project, allowing the combined cut-off and retaining wall to be constructed within a very narrow footprint (650mm width). The low noise impact and near vibration free construction of the CSM equipment provided minimal inconvenience to nearby stakeholders during construction. To reduce dewatering volumes during excavation and prevent significant water-table drawdown the Hydraulic Conductivity requirements for the wall were 1 x 10-7 cm/s or less. Project specifications called for a different strength requirement for upper and lower portions of the wall. The top 13 meters of the wall required an Unconfined Compressive Strength (UCS) of 4MPa to act as a retaining and cut-off wall, whereas the bottom 15 meters of the wall required a UCS of only 0.5 MPa to act only as a cut-off wall. Wet-grab and core samples were obtained from the panels to confirm the UCS and Hydraulic Conductivity specifications were met.INTRODUCTIONGolder Construction Inc. and GeoPacific Consultants Ltd. conducted the design and construction of a deep soil mixed cut-off and retaining wall system. The “dry-box” solution was used to surround the excavation of an underground parkade and prevent flows of groundwater into the excavation."

Jan 1, 2016

By Madan Kumar Annam, Hari Krishna Y, I. V. Anirudhan

"For completion of projects in time with positive results, improvements of productivity and effective project management procedures have become extremely important. This paper discusses a milestone project comprising 198 residential units of stilt plus 4 levels that highlighted the benefits of these key aspects. Success of ground modification procedure benefitting the entire cycle involving End Users, Suppliers, Bankers and Developer is discussed.Soil profile for a considerable depth comprises weak layers of silty clay and sandy clay with varying consistency. Deep foundations have been an automatic choice of foundation for major buildings constructed in similar environment. After serious geotechnical appraisal, reconsideration of the foundation system with an alternative solution of Ground Improvement was found to be optimal in terms of Cost and Time. Full raft foundation on the improved ground by installation of Vibro Stone Columns (dry bottom feed method) was considered as an alternative foundation system. The ground improvement works were completed within 6 weeks (as against 6 months to that of pile foundations) that was made possible through effective project management. Full size plate load tests were conducted to ascertain effectiveness of the ground improvement works. Success of the foundation system was proved by full scale monitoring of foundation settlement during and after completion of the project over a span of 2 years. This paper describes design considerations, quality control in the construction of Vibro Stone Columns (dry bottom feed method) and performance monitoring of the project thereafter.INTRODUCTIONGenerally in weak deposits, deep foundations like bored cast-in-situ piles and driven piles have historically been the foundation choice for major buildings and other structures. Construction of pile foundations is becoming a challenge due to their high cost, large construction time and due to severe environmental issues (noise pollution, ground vibrations and carbon footprint). Since the proposed building complex is located within the proximity of a well-developed residential locality, objections raised by neighborhoods to pile driving activities called for a rethinking on the foundation system.The top 6m to 8m of soil profile comprises of silty clay / sandy clay having highly varying consistency. GWT was encountered at 3.0m below the existing ground level. Under this situation, the reconsideration of the type of foundation system with respect to the geotechnical analysis gave a thought to assess feasibility of ground improvement system."

Jan 1, 2015

By Sushant Upadhyaya, Deniz Karadeniz, Ahmed Mohamed

Soil setup analysis provides opportunities for efficiencies in pile foundation design and installation. Soil setup gain with time was evaluated as part of the foundation design and installation for twelve bridges along the Interstate 64 corridor between York County and Newport News in Virginia. The substructure elements of the bridges consist of driven precast prestressed concrete piles or H-piles. This case study describes lessons learned to understand the soil setup phenomenon during the installation of the piles in coastal plain. We were able to make expedited decisions during construction by analyzing previously performed pile dynamic analyzer (PDA) test results within the project alignment. Data evaluation included analyses of PDA data obtained from initial driving and restrike after a few hours to 5 weeks. The test data showed pile resistance increase up to twice in most cases and as high as four times in some cases. Foundation design and acceptance based on soil setup can provide opportunities for cost savings and advanced scheduling during construction.

By Kazunori Matsushita, Masaru Sakakibara, Kenji Harada, Naotoshi Shinkawa, Mitsuo Nozu

The Sand Compaction Pile (SCP) method has been widely used as a typical countermeasure against liquefaction in Japan, and its effectiveness has been confirmed in many case histories of damages caused by the past large-scale earthquakes. A series of studies were conducted to evaluate the effectiveness of the compaction method and other factors, if any, in sustaining a seismic force that is greater than the assumed one and caused no damage. Based on the results of these studies, the Architectural Institute of Japan (AIJ) has indicated in its “Recommendations for Design of Ground Improvement for Building Foundations” published in 2006 that the liquefaction resistance ratio (tl/sz) of the composite ground, which consists of sand piles and surrounding compacted ground, is higher than the RL calculated by using the SPT N-values of the ground in-between the sand piles. In this paper, statistical analysis of safety factor against liquefaction, FL, was performed by using the SPT N-values of ground in Port Island and Rokko Island which were both fully reclaimed islands in Kobe city during the 1995 Hyogo-ken Nambu Earthquake (classified as intense shaking) and, together with the consideration of relative settlement, resulted in tl/sz of the composite ground being 1.5~2.5 times of tl/sz of the soil in-between piles after improvement. Furthermore, the liquefaction resistance curve of SCP-improved sites obtained from the relationship between SPT N-values and cyclic shear stress ratio during the 2011 off the Pacific Coast of Tohoku Earthquake, which was regarded as long-duration earthquake, was plotted to the left side of the curve originally proposed by Japan Road Association. Thus, the liquefaction resistance of the improved ground was found to be higher than that of the natural ground, even for the same SPT N-values, verifying the validity of the AIJ recommendation.

Jan 1, 2017

By Frédéric Rocher-Lacoste

On July 2nd, 2007, LCPC and LOADTEST performed a static loading test with an Osterberg-cell on a bored pile of 1600 mm diameter. The 56.50 meters deep test pile constructed by Trevi Spa for Soares da Costa group, was near the Cacheu river in Guinea Bissau. This test was conducted to validate the design of the foundations of the Sao Vicente bridge; a project undertaken by the Ministry of Public Works of the Republic of Guinea Bissau and funded by the European Development Fund. Sub-surface conditions at the test pile location consist primarily of layers of weak sands and clays. The piles were loaded statically using the O-cell® bi-directional method 25 days after concreting. The maximum sustained bi-directional load applied to the pile was 11.7 MN. At the maximum load, the displacements above and below the O-cell assembly were 6.6 mm and 81.9 mm, respectively. The resulting pile head behavior has been calculated for a combined skin friction and end-bearing load of 29.3 MN. The piles were also instrumented using LCPC removable extensometers, which made it possible to measure the mobilization of shaft friction and toe resistance. The adjusted test data indicated that this pile would settle approximately 12.2 mm for the service load of 12MN applied at the head of the pile. This paper provides a very brief presentation of the bridge project and the test pile instrumentation: LCPC removable extensometers and O-cell® instrumentation. The results are detailed and analyzed herein and the combined use of these two instrumentation systems is a world première.

Jan 1, 2008

By Aly Mohammad, Dongyi Yue

"The design of rock sockets for drilled shafts and piles proves to be a challenge for the Design Engineer. The magnitude of loads on the shaft and the behavior of the rock are critical in determining the required socket length. Several acceptable methods are available in the literature to analyze a rock socket under a combination of axial loads, lateral loads and moments. This paper will present a state-of-the-art methodology to analyze rock sockets utilizing deformation characteristics of the rock. This design methodology was implemented in the design of a major project in New York City.The project discussed herein is a marine transfer station planned for construction at East 91st Street along the East River in Manhattan. In order to support the piers and platform structures at a site with relatively shallow depth of the bedrock, rock sockets were required for the drilled shaft foundations. Rock sockets were utilized to provide the required fixity to the foundations and the structures. Acting at the top of the rock sockets are large shear forces and moments created by the lateral loads transferred from the structure.Upon review of the available techniques, a simplified method was proposed and used to analyze the rock sockets with a significant magnitude of lateral loading. The method recognizes two mechanisms through which the lateral shear and moment are transferred to the rock; a) load transfer through horizontal resistance of rock and b) the vertical shear resistance of the bond between socket and rock.The first load transfer mechanism was analyzed using the p-y curve method based on a rock model developed by Reese. The second was analyzed using a bond stiffness derived from the formula and curves utilized in the AASHTO Specifications for calculation of rock socket displacement. By comparing the two mechanisms, the main contribution to the large horizontal shear force that developed in the rock socket is identified.The paper will present a summary of the design methodology utilized in determining the length of the rock socket. It is believed that the presented method will provide substantial cost saving in selecting the most economical and efficient design length."

Jan 1, 2005

By Y. El-Mossallamy

The piled raft foundation was extensive applied in the last two decades in different soil conditions e.g. in soft to stiff clay as well as in medium to dense sand and even in highly weathered rock. The piled raft is now applied not only to control the foundation settlement but also to minimize the required raft thickness to reach the most economic foundation design. An innovative application of the piled raft is its special adjustment to cases of foundations with large load eccentricities or very different loaded parts of buildings to avoid the need of settlement joints, which are especially complex below ground water table. Recently, the piled raft is applied for foundations of highway and railway bridges with special serviceability requirements regarding the allowable total and differential settlement as well as tilting. Actually numerical analyses are the mostly used design methods for piled rafts. For all day design practice a simple and modest design method is highly needed -at least in the first design stage- to check the feasibility of the piled raft on the specific project conditions. In this paper, a general overview on the recent innovative applications of piled rafts in Germany will be presented in a short overview. The results of the simple design method will be discussed and compared with the results of more enhanced numerical methods.

Jan 1, 2006

By Yoshinori Kurumada, Tatsuo Nagatsu, Keiji Uchida

"Cement deep mixing method has been utilized in the process of construction of an underwater tunnel in Singapore. The soil was improved by this method to prevent undesirable heaving of the soil below the excavated area. Quality control experiments approved the effectiveness of CDM method in increasing the strength of the soil and prevention of undesired heave of the ground. The process of the construction of this project and the quality control experiments results are discussed in this paper.INTRODUCTIONThe Marina Coastal Expressway is a 5.3 km long underwater highway tunnel with five lanes in each direction. It mostly comprises a twin box culvert structure (53.3 m exterior width and 10.89 m height) and was opened by the Land Transport Authority of Singapore (LTA).The contract zone C485 was the most challenging area of the construction; it involved a 700 m long underwater tunnel of which 400 m was built beneath the seabed at the mouth of the Singapore River. A double steel pipe sheet pile wall was built as a temporary cofferdam to keep water out of the excavation site, and the cut-and-cover method was used for excavation. In order to ensure a sufficient cross-sectional area for the flow of the Singapore River, the construction was divided into two phases focused on the left bank (Stage 1) and right bank (Stage 2).The Cement Deep Mixing (CDM) method was used to improve the ground, which comprised soft marine clay, to ensure safety during the excavation. The efficiency of this method in increasing the soil’s strength was approved previously. The design standard strength was quck = 800 kPa. Based on the study conducted after the construction, the average the Unconfined Compression Strength (UCS) of the soil stabilized by the CDM method was quf =3,000 kPa. This paper discusses the effect of the CDM soil improvement construction on the reduced displacement from the excavation and the quality control of the soil improvement."

Jan 1, 2015

By Hayel M. El-Naggar, Mohamed Sobhi, Mamdouh M. Hamza, Marawan M. Shahien

"This paper presents the results of two lateral load tests on large bored piles in soft clay deposit for a major site in northern Egypt. The tests are carried out on 0.8 m diameter piles. One of the tests is carried out on the pile where the clay starts from the ground surface. The other test is carried out on a pile after surface improvement by replacing the top 1.50 m of the clay deposit by compacted granular soil. The results of the tests show the influence of the surface replacement layer on the lateral load versus lateral displacement relationships of the loaded pile. The results of the two tests are used to calibrate a 3D Finite Element Analysis model for the pile. The model is used to investigate the influence of the thickness and lateral extent of the surface replacement layer on the behavior of laterally loaded large bored piles.INTRODUCTIONLateral loads for piles are produced by seismic events, wind, wave action, ship impact, traffic, and land slide forces. The lateral resistance of a pile is controlled by the stiffness and the strength of the material of the pile and the soil surrounding the upper portion of the pile. In most situations, the soil surrounding the upper portion of the pile is too weak to sustain the design lateral loads. Thus there is a need to increase the lateral resistance of the pile or groups of piles. Such an increase may be achieved by either increase number of piles or increase pile diameter. Alternatively, an economic way to increase the lateral resistance is to improve the soil surrounding the upper portion of the pile (Rollins and Brown, 2011; Faro et al., 2015).Ground improvement has the ability to increase the lateral resistance of the pile by increasing the passive resistance of the soil surrounding the upper portion of the pile. The ground improvement techniques have the potential for being more cost-effective and reducing construction time. In spite of this fact, such techniques are rarely implemented in practice. Further, there are relatively few tests or records available in the literature to guide engineers in evaluating the actual effectiveness of this approach. In addition, there is no standard or methodology to aid engineers in designing increase of lateral resistance with surface ground improvement. There are specific improvement methods for each soil type, whether it is loose cohesionless soil or soft cohesive soil and these methods are provided by Michell (1981), Tershai and Juran (2000), ASCE (1997), and Rollins and Brown (2011). Furthermore, there are number of case histories that add a new hole in the sight, such as the cases provided by Brown et al. (1987, 1988), Mokwa and Duncan (2001), Rollins et al. (2005), Rollins and Cole (2006), Cole and Rollins (2006), Rollins, Snyder et al. (2010) , Rollins, Gerber, and Kwon (2010), Rollins and Nasr (2010), and Gerber et al. (2010)."

Jan 1, 2016

By A. Lyndon

Vertical and lateral load tests were carried out on two 13 m deep bored cast-in-place instrumented piles, socketed into weathered sandstone. The first pile, 1200 mm in diameter, was loaded vertically to a maximum of 16000 kN and then loaded to failure under lateral load (1900 kN). The second pile, 1500 mm in diameter, was tested under lateral load up to a maximum of 2400 kN. It was found that the deflections of the 1200 mm pile were more than twice those of the 1500 mm pile under similar loads. The soils on the site are not easily tested in the laboratory, or by conventional insitu site investigation techniques, parameters needed in design can only be reliably obtained from pile test results. In this report shear moduli are back analysed from the vertical load test and the two lateral load tests. For these similarly installed piles very different design parameters were determined from the lateral load tests, the only known major difference between the piles being that the 1200 mm pile was loaded vertically before it was loaded laterally. Changes in G values needed to match performance under vertical load if applicable to lateral loading could have accounted for a significant amount of the difference.

Jan 1, 1989

By Seth H. Hamblin, Leo J. Hart, John E. Regan

The Route 6 /10 10 Interchange Design/Build project, located in Providence, Rhode Island, involves the design and construction of five (5) new elevated bridge structures to replace and reconfigure the existing interchange and to provide a link between Route 10 northbound and Route 6 westbound. Due to site logistics, headroom restrictions, and depth to bedrock, 50 ton drilled micropiles installed in the deep medium dense sand strata were initially proposed as the deep foundation solution. Post project award, Geosciences Testing and Research, Inc. (GTR) performed various analyses and developed an alternate driven pile solution using steel Tapertube. The results of these analyses indicated that driven steel taper tube and steel pipe piles could develop greater capacities than the drilled micropiles in the granular soil layer, thereby reducing the number of foundation elements, decreasing construction schedule and providing a more cost effective foundation alternative. A comprehensive driven pile load test program was subsequently executed by GTR and the Design Build Team led by Barletta Heavy Division of Canton, Massachusetts, to assess the performance of Tapertube and steel pipe piles, including pile drivability, load-deformation characteristics under static and dynamic loading, and to develop site-specific design parameters in two (2) distinct test areas. The test pile program included dynamic, static compression, tension and lateral load tests on each test pile. Load test measurements were automated with embedded Vibrating Wire Strain Gages (VWSG) to measure load transfer with depth. The execution and results of the successful pile load test program are presented and offer unique case study and valuable data for the use of Tapertube piles on deep foundation projects in the New England region INTRODUCTION The Rhode Island Department of Transportation (RIDOT) Route 6 / Route 10 Interchange is located west of downtown Providence. Originally constructed in the 1950’s as a highway bypass around the historic Olneyville neighborhood, the interchange consists of a series of nine (9) bridges and ramps that serve as a vital east-west link between Interstate 295, 95 and 195. Based on recent bridge rating assessments, seven of the nine bridge structures are rated “structurally deficient”. With many bridge structures shored with temporary supports as many as 15 years ago, the interchange is in critical need of replacement. In 2018, RIDOT awarded the Route 6/10 Reconstruction Design-Build Project to 6/10 Constructors, Joint Venture. Led by Barletta Heavy Division of Canton, Massachusetts, the Design Build team includes O&G Industries, DW White Construction, Aetna Bridge Co. and AECOM. The scope of work includes the replacement of the bridges and ramps, and will provide direct access from Route 10 northbound to Route 6 westbound. Valued at over $400M (US), this is currently the largest project awarded in RIDOT history.

Jan 1, 2019

By Tsuyoshi Honda, Kazuhiro Kaneda, Masayuki Imai, Kazuo Konishi, Kunio Higashinaka

"In recent years, the demand for measures to control liquefaction of existing airport runways and harbor structures has increased. However, from the perspectives of constructability and cost, application of grid-form deep mixing walls to these types of structures requires the formation of wider grid spacing as compared with conventional designs. In this research, we focused on the extent of liquefaction and ground surface settling when grid spacing is made wider than conventional designs. We conducted centrifuge model tests, and confirmed the liquefaction suppression effect when grid-form modifications involving wide grid spacing are adopted under asphalt pavement. The tests were conducted under conditions that included changing the grid spacing and groundwater level. When the groundwater level was high, an increase in water pressure was observed, even within the grid. However, when the groundwater level was low, the increase in water pressure inside the grid was suppressed. We also found that if the generation of water pressure can be suppressed, the amount of settling due to liquefaction can also be controlled.INTRODUCTIONOne construction technique used as a countermeasure to liquefaction is grid-form deep mixing walls. Grid-form deep mixing walls are a construction technique for which improved grid-shaped wall bodies are built into the ground below the surface using a deep mixing method. This construction technique minimizes shear deformation by surrounding liquefied ground with improved wall bodies, thereby preventing liquefaction (Fig.1). With conventional designs, grid-form deep mixing walls determine the grid spacing that can deter liquefaction based on a ratio of the grid spacing L to the improved depth H (ratio = L/H). Ordinarily, designs are implemented with an L/H ratio of 0.8 or less (PWRI, 1999).In recent years, a demand for measures to control liquefaction of existing airport pavement and harbor structures has increased. However, when liquefaction countermeasures are implemented at these types of facilities and structures, the construction work must be implemented while the facilities and structures remain in service. Therefore, temporal and spatial constraints must be considered. In addition, unlike conventional liquefaction countermeasures, performance requirements are such that, even if some degree of liquefaction is allowed, the performance is acceptable as long as the amount of settlement is within a predetermined value. Therefore, if grid-form deep mixing walls are applied to these structures, grid spacing that is wider than conventional standards is desired."

Jan 1, 2015

By Henry Zhang

This paper presents two case studies of large diameter driven tubular steel piles for the ongoing Woolgoolga to Ballina Pacific Highway upgrade (W2B). This project forms part of Australia’s largest regional infrastructure project and will upgrade about 155 kilometers of highway to four-lane, divided road. There are more than 170 bridges on W2B, and driven tubular steel piles are adopted on 43 bridges between Glenugie and Ballina. Driven piles terminating in soil or basalt is a big challenge faced by both designers and piling contractors due to 1) the uncertainty of expected pile unit shaft and base resistance in different soils; 2) whether plugging is formed; and 3) highly variable basalt strength and thickness near top of the rock. If these risks are not adequately managed during design or construction stages, it could lead to unexpected project delay, extra time and cost or pile toe damage in basalt. This paper describes two case studies, one for piles designed to terminate in soils and the other for piles designed to terminate in basalt. How these risks were assessed and managed during detailed design, procurement, hammer selection, pile installation and verification will be discussed in details with lessons learnt summerised in the conclusion.

Nov 1, 2022

By Yoshinori Kurumada, Masaya Watanabe, Kenji Sasa

"The Port of Yokohama is strengthening its international competitiveness as a strategic container port in order to respond appropriately to global exchange and shipping demands. Thus, the Minami Honmoku main Pier is currently being developed. The high-standard container terminals MC-1 and MC-2 have already started their service, and the development of the container terminals MC-3 and MC-4 is currently in progress.Because the South Honmoku Pier plays an important role in waste disposal management of Yokohama, a final waste disposal site (controlled final landfill site) is being developed in Block 5 to provide long-term and stable reception of waste that will be generated in the city. For this project, a revetment with water-blocking properties and an extension approximately 1.7 km in length is being built in order to prevent water from leaking from the disposal site. The base part of the revetment will be subjected to foundation improvement using the Cement Deep Mixing (CDM) method in order to secure water shielding of the soft sediment underneath the water, prevent slipping of the seawall, reduce the amount of subsidence, and increase the foundation support force.This report presents a preliminary study on using CDM on reclaimed soil and the construction process of the development project of the disposal site in Block 5 of the Minami Honmoku Pier, which has been underway since 2007.ABOUT MINAMI HONMOKU PIERThe development of the Minami Honmoku Pier started in 1990. It was designed to develop high-standard berths with greater water depths in order to handle the increasing volume of foreign container cargo and growing size of vessels. Figure 1 shows the layout of Minami Honmoku Pier. In April 2001, the Phase 1 (MC-1 and MC-2) began services. This is the newest pier in Port of Yokohama.This pier has one of Japan’s largest terminal areas (40 ha) and is equipped with 22 row-type mega gantry cranes capable of handling the newest ultralarge container ships. The pier has a quay with a water depth of 16 m, which is the first in Japan. The pier is equipped with advanced facilities and equipment to let Port of Yokohama be internationally competitive and function as an international commercial hub. An innovative system for high-efficiency transport is currently being introduced; it includes the installation of waiting vehicle lanes and a reservation-based loading and unloading system.Since the fiscal year 2007, a new container terminal (MC-3) with a -20m deep quay capable of handling the increased size of container ships and the diversification of port logistics has been under construction and is nearly completed."

Jan 1, 2015

By Ralphie Adams, Tiana Rasmussen, Ashley E. Shirer

Transmission line foundation designers must rely on limited subsurface information, from easily accessible locations, resulting in subsurface uncertainty, increased design risk and increased construction costs. This paper presents a different approach for foundation analysis conducted in mountainous and alluvial floodplains located northwest of Phoenix, AZ. The region is dominated by fault-bounded, northeast dipping mountain ranges, where rock types and drillability can vary from granite to intact basalt. The valleys between are comprised of “basin-fill” deposits ranging from conglomerates and cemented soils to lose alluvium. Recently deposited alluvial fills can vary in depth significantly from location to location due to erosion and deposition from active and historic hydraulic features. To limit the subsurface uncertainty for foundation design, a phased approach using geophysical surveys along with detailed geologic reconnaissance was employed. Both compression wave and shear wave velocities were measured in order to identify the depth and properties of loose erodible materials from more scourresistant cemented, conglomerate, and rock deposits. These analyses were used in combination with limited subsurface drilling and sampling to evaluate direct embedment steel pole foundations for over fifty structures. Post analysis results from limited construction drilling reports were used to assess this approach.

Sep 8, 2021

By Alexander J. Verstraeten

The design and construction of foundations for power transmission line towers present some special problems. This paper describes a system of design and construction for these foundations that was developed in Europe and has attained general use there because of its reliability and cost effectiveness. Transmission line foundations distinguish themselves by having to deal not only with compressive and lateral loads, but with uplift loads and, because of the wind (in some regions earthquakes), with dynamic loading. The construction of transmission line foundations distinguishes itself mainly in the great number of inaccesible locations involved, resulting in extensive geotechnical investigation and logistical problems in moving men, materials and equipment.

Jan 1, 1987

By Larry Stearns, Lori Tiefenthaler

Remediation of contaminated soil represents a significant market for application of Deep Soil Mixing (DSM). Eighty-one percent of U.S. Environmental Protection Agency (EPA) Superfund Program’s site remedies have involved contaminated soil. Contaminated soil is frequently treated by In-situ Solidification/Stabilization (ISS). ISS treatment of contaminated soil involves mixing binding agents into soil using DSM techniques. DSM is a core business for many DFI members. Members may improve and broaden their services to clients by learning about the recent ISS treatment of contaminated soil at a Superfund site. ISS treatment is part of the EPA-selected remedy for a Superfund Site in the metro New York City area. The property has seen heavy industrial use for more than a century. Soil at the site is contaminated with a variety of volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs) including coal tars and heavy metals, principally arsenic and lead. Beginning in 2017 and continuing through 2018, approximately 150,000 cubic yards (115,000 cubic meters) of soil will be treated by ISS at the case study site. Portland cement and slag cement are mixed into the soil by DSM techniques using GPS guided excavators to immobilize the hazardous constituents within the treated soil. ISS treatment by DSM will contribute to redevelopment of this valuable property. This paper will describe ISS constructability and performance, case study grout mix design with geotechnical results for strength and permeability, and deep soil mixing techniques. INTRODUCTION In-situ solidification and stabilization (ISS) is a deep soil mixing (DSM) technique applied in the environmental remediation field to physically encapsulate, or chemically bind, contaminates of concern such that the impacts to human health and the environment are mitigated. Common remediation applications of ISS include mixing cementitious reagents into contaminated soils to form a monolithic mass with desired performance characteristics, and the installation of vertical subsurface walls designed to control groundwater movement. A key characteristic of ISS is that the contaminated soils are treated in their existing location at the project site and then are left in place after treatment. Typical performance characteristics of the ISS treated soils include improved unconfined compressive strength (UCS), reduced hydraulic conductivity (HC), and reduced leaching potential of soil contaminants. Increased shear resistance of the treated soil may also be a performance requirement where seismic loading is a concern.

Jan 1, 2018

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

By Vladimir M. Korolev

The field studies conducted at the experimental-production sites allowed to develop the technology of arranging drilling piles in loess subsiding grounds over 25 m deep and over 250 mm in diameter, to select optimal compositions of flush fluids, to assess the carrying capacity and field of use of the piles under test and to produce a special equipment. The dependence of the ultimate axial pressing-in load on pile driving into the non-subsiding section, its diameter and method of fulfillment, as well as the ground moisture dependence of the specific ground resistance along the piles' side surface within the limits of the subsiding section were determined. The study results allowed to reduce the length of the work piles and the number of bars in the reinforcement frames. The obtained experimental data enable to give a preliminary assessment of the piles' carrying capacity under complicated engineering-geological conditions of subsiding grounds.

Jan 1, 2002

By Kiyotaka Ohno, Nobushige Yasuoka, Yosuke Hioki

"The diameter of improved columns adopted by the original DJM Method had been 1000 mm, however, in order to comply with the social need for construction cost reduction, the Expanded Dry Jet Mixing (EX-DJM) Method with maximum column diameter expanded to 1300 mm was developed between 1998 and 2001 and has been widely applied since then. From the first application of EX-DJM in January 2002 for a first construction project, the total volume of improved soil has reached 325,000 m3 in 17 projects up to September 2014. Because of the advantages of the EX-DJM such as reduction of construction costs and periods leading to reduction in the number of improved columns, adoption of this method is expected to increase in the future. This paper describes the advantages of the EX-DJM, its construction results and case examples including those applied to restoration projects after the Great East Japan Earthquake, 2011.1. BACKGROUND OF DEVELOPMENTThe Dry Jet Mixing (DJM) Method is a soil stabilization method in which a powdery or granular binder is pneumatically fed into and mixed with soft soil to induce chemical reactions that stabilize and strengthen the soil. It was developed by government - private collaboration in Japan between 1977 and 1979. Up to March 2014, the total volume of soil improved by DJM method reached 33,500,000 m3. The initial diameter of improved columns of the original DJM Method was 1000 mm. In order to comply with the social need for construction cost reduction, the Expanded Dry Jet Mixing (EX-DJM) Method with maximum column diameter 1300 mm was developed between 1998 and 2001.2. ADVANTAGES OF EX-DJMThe construction equipment for the EX-DJM consists of two major parts, which are DJM machine and binder plant are shown in Fig. 1.The construction machine is of double mixing-shaft type with its column diameter expanded to 1200mm or 1300mm. In association with the increase in the column diameter, the binder feeder has also increased its discharge rate by approximately 1.69 times. Same as the increase rate of the area of original diameter 1000mm to diameter 1300mm are shown in Fig. 4."

Jan 1, 2015