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By Tracy Brettmann

Equipment ? Hollow Stem Auger ? Drill Bits ? Leads/Torque Arm ? Hydraulic Gearbox ? Hydraulic Power Unit ? Grout Pump ? Crawler Crane

Jan 1, 2004

By Gordon King

The City of Atlanta Water Department required the construction of a two sludge tanks and a wet well at the existing Chattahoochee Water Treatment Plant. Western Summit won a design build contract to build the project and proceeded to evaluate the wet well size options, and construction procedures. The final design required the construction of a 1 million gallon tank. The proximity of the underground tank to adjacent roads and existing plant structures ruled out laying back the excavation. As a result a tied back sheet pile retaining wall was initially proposed.

Jan 1, 2003

By B. Broms

The "Bawang Pile" (in english "onion" pile) described in the article consists of a cased concrete shaft and an expanded base. The steel casing is first driven by an internal drop hammer and then the base is formed in-situ by the raming the concrete at the bottom of the slitted casing. This new type of pile can be used for underpining (small head room) of buildings and as foundation for transmission towers or lamp posts. Full-scale load tests in compression and in tension on the Bawang pile and on steel pipe piles demonstrate the dramatic increase of the ultimate capacity due to the expanded base. Guidelines for the design of such piles are proposed.

Jan 1, 2010

By Robert L. Parsons

This paper describes the results of a detailed analysis of a loess deposit at the deep foundations test site established by the Kansas Department of Transportation. Multiple CPT, SPT, and pressuremeter tests were conducted as part of the investigation. This paper includes an evaluation of the effectiveness of common correlations used with the CPT, SPT when used for classification of loess and estimating its properties. Results show that common correlations must be used with caution as significant errors in estimation may result from using methods developed for other soil types. Laboratory testing included direct shear, triaxial, collapse, and consolidation testing, with many of the tests conducted on both vertically and horizontally oriented samples to evaluate anisotropic behavior. The results showed that strength properties could be considered to be isotropic.

Jan 1, 2009

By Carl-John Grävare

This paper deals with some of the systems and equipment that are being developed and/or are in use in Scandinavia. The main subject is the development of loading tests on the piles using monitoring equipment. This paper also describes ground improvement using lime-cement columns, expander body piles and steel core piles.

Jan 1, 2000

By Randy R. Huberty

Although originally designed with deep foundations consisting of all driven steel H piles and drilled caissons, a unique application of Augered Cast-in-Place (ACIP) piles as an alternate design resulted in a significant cost savings for the Midfield Terminal Project at the Pittsburgh International Airport. The project was enormous in scope covering an area two miles long by one mile wide, with changes in elevation of over 200 ft. The varying geology combined with the large amounts of fill required resulted in a complex set of geotechnical design parameters that had to be evaluated through both load testing and analyses. A total of almost 400,000 lineal feet of ACIP piles were installed for this project.

Jan 1, 2001

By G. G. Goble

Significant progress has been made in the past decade in determining the load bearing capacity of pile foundations. Developments in the means of prediction of pile capacity as limited by soil strength have been substantial, particularly in the use of dynamic methods. The use of currently available equipment, analytical procedures, and practices in the field, will often produce material economies on a job by allowing increased loads with proven factors of safety. This approach justifies the minimum number of piles required for a safe foundation in a wide range of job sizes and soil conditions. To avoid exposing the reader to excessive detail in the body of this paper, technical topics have been covered more thoroughly in several appendices. I. Wave Equation Analysis of Piles Appendix A II. Dynamic Monitoring and the Pile Driving Analyzer Appendix B III. Case Method Capacity Calculation Appendix C IV. Case Pile Wave Analysis Program Appendix D 1 Preliminary Analysis In designing driven pile foundations, there must be a close relationship between design, construction control procedures, driving practices, and the size of the job. Small commercial buildings or residences involving loads that are only a fraction of the pile capacities do not justify the expense of detailed design processes or elaborate construction controls. Nevertheless, some preliminary analysis of the job requirements and a limited subsurface investigation must be made to understand existing conditions and the possible foundation solutions. In other words, it is necessary to determine that driven piling is the best overall choice of foundation.

Jan 1, 1988

By S. Ali Bastani, Ashley Varni

Design acceleration response spectra (ARS) are directly correlated with dynamic forces and estimated dynamic bridge displacements, which make them a critical aspect of dynamic bridge design. Nonlinear site response analyses are performed for a 1,400-linear-foot bridge site with a SC soil profile at the sides and a SF soil profile in the middle to evaluate the soil profile effects on the bridge analyses. One-dimensional seismic response analysis is commonly performed for site-specific response analysis. SHAKE or similar one-dimensional total-stress equivalent-linear approaches have been used since the 1970s. However, the equivalent linear method has deficiencies when the subsurface soils are susceptible to strain softening. Therefore, various assumptions are made when using the equivalent linear method by practitioners to estimate the SF soil profile site response. With recent advancements in constitutive models, effective stress models have become more popular. Although the effective stress models are generally more complicated and require additional input parameters, they shed further light on the liquefaction mechanism and its effect on the surface ARS. An equivalent-linear one-dimensional seismic response analysis and a non-linear effective-stress seismic response analysis, using DEEPSOIL, were performed to evaluate the ground surface ARS for a proposed bridge site in Orange County. The soil shear strengths were estimated based on cone penetration test results using empirical relationships. The shear modulus degradations (backbone curves) of soil layers were adjusted to match the estimated soil strength at failure. The ARS curves developed from each method were compared to determine the most suitable method for estimating a site-specific design ARS curve for a liquefiable site. Considering that the bridge abutments and the outer bents are founded in bedrock, while the middle bents are founded in liquefiable soils, ARS curves were created for each subsurface condition. Taking into account limitations of the structural analysis software, recommendations were made to combine the multiple ARS curves into a single ARS curve for the structural bridge design.

Jan 1, 2018

By Shane Baker

Cementation Foundations Skanska Ltd encountered many significant challenges in designing and constructing the foundations for the LNG (Liquefied Natural Gas) tanks and associated structures at the Isle of Grain, Kent, UK. With LNG cargo ship levels fixed by the adjacent English Channel, the platform could not exceed critical thickness in order to achieve final grade level, so a safe and efficient working platform for construction equipment on extremely poor alluvial soils was designed and installed. The detailed pile design also required particular analysis of the pile group behaviour and considered seismic load cases not usually associated with UK pile design. Continuous flight auger (CFA) piles were the chosen foundation solution and design was verified through preliminary and working pile tests both axially and horizontally. Contaminated land and existing foundations from a previous oil terminal meant that removal of spoil was extremely costly so specific measures were taken to minimise the off-site disposal. The management of a package of general Civil Engineering in addition to the piling scope, coupled with an unrelenting production program has forced a raising of the bar for this foundation technique.

Jan 1, 2006

By Peter Chou

A total of 117 slope stabilization drilled piers were installed as part of a major hillside revitalization project. The 110-million dollar development, known as Stratford at Kenwood, included an 18-story upscale senior residential tower, a 3-story healthcare building, and 4-story condominium buildings, offering approximately 580,000 square feet of living space with panoramic views of Downtown Cincinnati, Ohio. In an effort to establish a flatter hillside plateau for the new 4-story condominium and to create a cut and fill balanced jobsite environment, an 800-foot long row of drilled piers and a 600-foot long multi-tiered shear key system was used to terrace existing 1.5H to 3H: 1V steep slopes and support the new fill. These slope stabilization features reduced the amount of spoils needed to be wasted off-site and mitigated the risk of slope instability. An ODOT/FHWA research indicated that spacing of stabilization piers and necessity of top-connecting elements are highly dependent on pier diameter, spacing, soil type, depth to potential failure surface, surcharge loads, and pier deflection. Due to pre-existing deep buried swales, various load combinations, and the complex mechanism of soil arching effects between adjacent piers, both analytical and numerical computer modeling was performed to estimate the loading on each pier. New generation multiplexed, 3-Dimensional, Micro-Electro-Mechanical-System based inclinometers were installed between selected piers to confirm the pier design, and monitor the fill placement, as well as long-term slope stability.

Jan 1, 2009

By [D. N. ] Naresh

During different activities pile installation like pile boring, concreting etc., it is likely that various problems, depending up on site condition may be encountered. There are possibilities that some of the activities if not correctly followed may affect the pile capacity. This paper describes few problems encountered during pile execution at different sites and presents the remedial measures undertaken to overcome them.

Jan 1, 1996

By Anne Lemnitzer

Full-Scale cyclic field testing was performed on a 3x3 pile group consisting of nine cast-in-drilled-hole (CIDH) reinforced concrete shafts and a comparable single-shaft in order to investigate group interaction effects. Both specimens were constructed with pile diameters of d = 0.61m (2 ft), fixed head boundary conditions, and placed in stiff clayey soil at a test site near the LAX Airport in Southern California. Internal instrumentation was installed in the single pile as well as in three piles within the pile group to obtain pile curvatures. External instrumentation controlled the lateral displacement of the specimens. A combination of experimentally and analytically obtained p-y curves for the single pile was used to simulate results for piles located in the group when field data were not available. All test specimens were tested to structural failure and excavated after test completion to investigate pile damage and plastic hinge formations. Calculated group interaction factors ranged between 1.0 at very small displacement levels of <2.5 mm (0.1 in), 0.8 at the initiation of the pile-soil-pile interaction, i.e. between 4 mm - 15 mm (0.16-0.6 in), and increased towards 0.9 near structural failure (displacement >25 mm or 1 in). A literature set of p-multipliers was found to reproduce an accurate fit to the available load displacement test data from the group.

Jan 1, 2010

By Jorge Beim

Helical Piles are increasingly being used to support and rehabilitate structures subjected to compressive axial loads. Traditionally, empirical correlations between installation torque and load capacity of helical screw piles are used as the field quality control. Load tests, however, are always recommended to validate the installation process and design methodology. This paper describes a test program performed on helical piles installed at the National Geotechnical Experimentation Site of the University of Massachusetts - Amherst campus (UMass-Amherst), well known for its deep varved clay deposit. Seven of these piles were submitted to Dynamic Load Tests using the Pile Driving Analyzer® (PDA), and also to Static Load Tests. Good agreements were obtained between the results of the dynamic and static load tests, encouraging the use of the former testing method as a viable alternative to the latter for determining the compressive load capacity of helical piles installed in cohesive soils. The results of the load tests were also compared to the predictions based on torque correlations, resulting in correlation coefficients which were higher than the ones traditionally used.

Jan 1, 2012

By James S. Graham

Specifications for treated round wood piling are presented for the engineers consideration. Included in the text are background information, technical committees, Chellis, quality, treatment, static and dynamic stresses, accessories, and existing codes and standards. The specifications are also available using Word Perfect on 3.5 or 5.25 inch size disks provided by the National Timber Piling Council. Note: DFI recommended wording is wood, head, and toe, instead of timber, butt, and tip.

Jan 1, 1992

By Joel Moskowitz

A new office complex is being constructed within 25m of the Hudson River in New Jersey. The project, about 140 m by 100 m, will include 4 basements under the entire footprint. The perimeter was to be secured by a 0.8 m thick diaphragm wall, laterally supported by high capacity tieback anchors to rock. Columns were to be supported on footings or piers to rock at a nominal bearing pressure of 3.8 MPa at depths up to 17m. Although some variation in rock quality was observed in borings, a substantial vertical seam of weathered and/or decomposed rock, 1 to 2 meters wide by as much as 8 meters deep, was encountered during construction necessitating field redesign. In some locations the seam dipped below more competent rock. Footings were redesigned for support on drilled caissons, or soft rock was excavated and replaced with concrete necessitating a reduction in bearing pressure of the footings by one half.

Jan 1, 2002

By Sanjeev Malhotra

The American Petroleum Institute (API) method of predicting pile capacities in sands is reviewed. Factors that influence pile capacity such as soil parameters, pile parameters, loading effects and installation effects are listed. In addition, the simultaneous occurrence of physical phenomena such as grain crushing, pile shaking, stress-redistribution and plugging add to the uncertainty in the prediction model. To better understand the method of prediction, each parameter and the associated uncertainty is revisited. It is evident that these factors are inter­related and sometimes compensating. This discussion also draws attention to the influence that pile installation procedures can have on pile capacities and highlights the need for field experience with various pile installation procedures for designers. In summary, the strength of the method lies in its simplicity and ease of application, but the possible savings generated by an improved method are too substantial to ignore.

Jan 1, 2000

By Scott A. Walker, Roberto A. Lopez, Lori A. Simpson, David A. Shook

500 Folsom Street is part of the new Transbay neighborhood in San Francisco, which is being redeveloped after the 1989 Loma Prieta Earthquake damaged a freeway viaduct; removal of the viaduct created parcels of land available for development. The development consists of a 42-story residential tower with a six-level basement. The slender, core-only structure was designed using performance-based seismic design. Subsurface conditions include undocumented fill, Dune sand, marsh deposits, sand, and clay, all overlying sloping bedrock of the Franciscan Formation. The building is supported on a 10-foot-thick mat foundation approximately 62 to 72 feet below street grades; clay, sand, and bedrock are all present at mat subgrade. Under a portion of the mat, sand susceptible to liquefaction was present. The variable subgrade conditions and potential for ground failure, along with the depth of mat subgrade below street grade, created a challenge for the design and construction team to solve. The ground below mat subgrade needed to be improved to mitigate the liquefaction potential and provide more uniform support. The areal extent and depth of ground improvement necessary to support the mat with an acceptable amount of deformation was determined. Settlement was analyzed and subgrade moduli were provided for design of the mat, with multiple iterations performed to converge between the geotechnical and structural models. Based on the project schedule and logistics, it was beneficial to work from street grade to improve the ground. In order to target the depths below the mat and minimize wasted effort and materials within the depth of excavation, grids of jet grouting were determined to be the most economical ground improvement method; however, it was challenging to install the columns from 65 feet above the top of the target zone. During installation, QA/QC was performed to check that the jet-grouted columns were installed to the design depth and diameter and developed the design strength.

Jan 1, 2018

By Kazimierz Gwizdala

In recent years, in Poland the ATLAS piles have been successfully applied for some constructions near Gdansk. The piles have been used as foundations for housing and another areas of civil engineering, in delta Vistula geotechnical region, characterized by weak, highly compressible soils represented by mud and peat, lying in sub-surface layers, several meters thick. Usually below are dense sandy soils or gravel. In all cases, the base of ATLAS piles rested on sandy soils. The analysis of pile bearing capacity has been discussed and verified by static pile load tests (SPLT). The load-settlements characteristics obtained were satisfactory. In the paper, the results of geotechnical investigations as well as calculations and load tests are shown. The ecological aspects of ATLAS piles application within highly urban areas of the cities and complex geotechnical conditions are emphasized.

Jan 1, 2006

By B. H. Moore

The opportunity to evaluate the pile design procedures used on a major project is an infrequent occurrence. It is even more infrequent that the project involves piles with significant tension and horizontal capacities. This report synopsizes over twenty years of design and construction experience on just such a major pile founded structure. The philosophy governing foundation design procedures is described and discussed. The order and extent of full scale pile testing are evaluated. Principal points in the specifications are established and their effect on construction progress and claims are noted. The report concludes with recommendations for future projects.

Jan 1, 2010

By Jan A. Nilsen

This paper describes a key element in the construction of a major project undertaken by Harbourfront Corporation in its efforts to rejuvenate the central Toronto waterfront. The Spadina Pier forms one of the two major structures of the $10 million marina complex. Completed in early 1986, the 150 metre(490 ft.) long by 43 metre(140 ft.) wide pier structure will contain a 320 car parking garage as well as providing the foundation of a 17-story residential tower and a two-story retail/commercial complex. However, the pier structure posed a considerable challenge to its developers due to the the many restrictions imposed on the site by the environmental authorities which ruled out the construction of dykes or the placing of other fill materials on the highly contaminated bottom sediments. In addition, access at the site was restricted by its proximity to the main harbour navigation channel and a grain elevator berth. The original design called for a cofferdam to form an integral part of the finished structure. However, the contractor chose to regard the cofferdam as a temporary structure and proposed to construct the pier in the dry by enclosing the 10,000 square metre(107,600 sf) site with a 450 metre(1480 ft.) long single wall steel sheet pile cofferdom 7.5 metres(25 ft.) from the final pier structure. This paper will describes the design and construction of the cofferdam. Prior to finalizing the pier design, a geotechnical investigation of the shale bedrock was undertaken as well as a small sheet pile test cell program to evaluate the feasibility of driving a Canadian manufactured cold-rolled sheet pile into the bedrock. Relying on the design parameters for the shale bedrock, Foundation designed the cofferdam utilizing a post-tensioned bipod bracing system to resist a 7 metre(23 ft.) hydrostatic head as well as the maximum wind and wave forces expected at the site. The bipod bracing system consists of diagonal H-pile raker piles and verticle pipe piles anchored to bedrock with post-tensioned anchors grouted into bedrock.

Jan 1, 1987