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By D. E. Sherwood

Recent developments in high torque hydraulic rotary rigs has lead to the construction of secant bored pile walls by rotary drilling methods in circumstances where earlier methods were difficult and in some cases impossible. The evolution of secant bored pile wall construction is described including classical, rotary drilled and continuous flight auger construction methods. The paper then details the restraints which have been created in recent inner city redevelopment, many of which were not relevant in the early days of the technique. Typical examples of walls are presented to show the adapatability and advantages of the secant bored pile wall method. A number of in-situ retaining wall construction techniques are then compared in detail with regard to relative cost, technical quality and practicality.

Jan 1, 1989

By W. Sondermann

"AbstractWith the increasing demand in reuse of inner city areas and the urgent need for deeper foundation pits under cramped circumstances, adjacent structures close to and high ground water level, the well-known established technologies especially with small to mid-sized dimensions are often too time consuming and occasionally not economic to install lateral support systems. The alternatives for these specific cases could be the usage of the deep mixing technology to create lateral support systems in reinforcing the deep mixing elements additionally to transfer the horizontal loads from earth – and water-pressure.With increasing demand in depth and water tightness, verticality and overlapping of single column solutions are becoming the key in execution. In addition, for some applications subsoil-conditions were not ideal for wet deep mixing technologies. The tubular soil mixing system (TSM) as a combination of mechanical mixing and support of hydraulic cutting by jet grouting can provide solutions toovercome these challenges.1. Current market conditions and trendsThe present financial crisis and the efforts not only to consolidate national budgets, but also to rescue certain banks, have not left the building industry unaffected either. Some drastic cutbacks to public budgets, along with the increasingly restrictive granting of credit for the financing of construction projects, have led to enormous over-capacities in the building sector, with purely negative impact. As a consequence of these negative developments, many companies are experiencing the pressure to restructure more quickly and to reduce costs but at the same time to keep the consequences of all activities, both externally and internally, within limits acceptable to employees, owners and finance institutions and last but not least consumers."

Jan 1, 2014

By S. K. V. Avasarala

This paper presents a case history of design, prediction, probe and production pile driving monitoring, loading tests and installation of over 3,300 prestressed concrete piles for a building complex consisting of 12, 5- and 6-story over parking buildings. The project was recently completed in three-phases over a span of 4 years. The subsoil conditions were explored by performing 25, Standard Penetration Test (SPT) borings throughout the site. Various types of driven pile foundations were considered and following an evaluation of high structural loads and site-specific constraints such as variable depth of bearing layer of Florida limestone and quality of clay and limestone layers, a prestressed concrete pile support system was selected as the most economical and effective foundation approach. The building foundations were designed for a pile capacity of 353 kN (40 tons) in compression, 45 kN (5 tons) in lateral capacity for a deflection of 0.64 cm (0.25 in.), and 133 kN (15 tons) in uplift capacity. The axial and lateral allowable pile capacity and lengths were predicted using SPT91 and LPILE computer programs, which are generally used in Florida. The validation of these capacities was derived from 144 probe piles and performance of 12 pile loading tests on selected probe piles. Prior to installation of probe or production piles, a termination criterion was established using 1-dimensional wave equation analyses in addition to the design pile embedment requirement. The predicted pile capacities compared very well with the capacities from the loading tests on probe piles. This information was effectively utilized as part of the overall quality control program to install a total of 4,186 prestressed concrete piles (including 144 probe piles) in different building areas across the project site to depths ranging from 8 to 21 m (25 to 90 ft) below existing ground elevation as part of foundation support system. This engineered, monitored, and tested foundation solution provided an effective and satisfactory basis for completion and approval of the foundation work for this 12, 5- and 6-story over parking building complex. A recent reconnaissance has indicated that all the building foundations are performing satisfactorily.

Jan 1, 1995

By Makoto Kimura

Failure tests on laterally loaded single and pile group are analyzed with a 3-dimensional elasto-plastic finite element program. In the analysis, the mechanical behavior of the ground is supposed to be elasto-perfect plastic with Drucker-Prager's yielding criterion. The nonlinearity of the piles is simulated by assuming a hyperbolic relation between the bending moment and the curvature of the piles. The influence of the axial stress on the cast-in-place concrete piles is also considered in the numerical analysis. It is found that the mechanical behavior of the piles subjected to lateral loading, such as the load-displacement relation up to an ultimately large deformation, and the distribution of bending moment in the pile group can be well simulated.

Jan 1, 1996

By B. N. Hira

A multistoreyed residential complex was at the penultimate stage of construction by ONGC at Nazira, Assam. The site was situated at high earthquake zone. The subsoil was very weak and contained soft to medium clay with water table almost at the ground level. The bearing capacity of soil was quite poor particularly with predicted settlement beyond permissible limit. In this situation, the conventional shallow and deep foundations were found uneconomical and ground improvement with granular piles was considered as the viable solution. ONGC approached the Central Building Research Institute with the request to design granular piles along with R.C.C. foundation and other suitable cost effective measures. CBRI collected relevant geotechnical informations and supplimented the data by conducting field tests at site and laboratory tests at Roorkee. Rational design of 30 cm dia. and 5.00 meter deep granular piles were suggested with isolated and combined RCC footings over the reinforced soil. In addition to several structural and geotechnical advantages, the granular pile foundation provided considerable economy in the cost of construction. The paper presents the salient geotechnical and structural informations of the challenging project and provides the design details of the innovative granular pile-system. It also furnishes the design approach of the RC footings and other elements of the foundation.

Jan 1, 1996

By Paul J. Axtell

Self-hardening cement-bentontie (c-b) slurry walls were constructed as shear walls to stabilize the downstream slope of Tuttle Creek Dam near Manhattan, Kansas. The slope stabilization was required to protect the existing pressure relief well system located at the downstream toe of the dam. The wells require protection from slope deformation induced by liquefaction of the foundation sands during or immediately after the design seismic event. The shear walls are transverse to the axis of the dam, unreinforced, and relatively brittle members that may be exposed to relatively large shear strains, and possible cracking, during or immediately after shaking. An extensive laboratory investigation was conducted on recovered core samples to optimize the mix design and stabilization scheme. Furthermore, as is the topic of this paper, a portion of the laboratory investigation was to determine the large-strain, or post-peak, shear strength of the c-b material for use in limit-equilibrium slope stability analyses and numerical deformation modeling to assess the magnitude of permanent deformation caused by the design earthquake. These data may be beneficial to other projects that are considering the use of unreinforced c-b slurry walls for seismic retrofit purposes.

Jan 1, 2010

By Brian Isherwood

TransCanada Pipelines, Calgary (TCPL) is one of North America's leading transporters of natural gas through its energy transmission business. TransCanada also operates significant complementary businesses in energy marketing and energy processing in North America and internationally. The main trunk pipeline crossing Canada comprises as many as six pipes, 30" to 48" diameter delivering up to 7.8 trillion cubic feet of natural gas per day. To maintain the maximum operating pressure of 1000 psi, it is necessary to provide compressor stations at 60 to 100 km spacing. One such station is located at Potter, in northern Ontario, some 80 km north of Timmins, referred to as Station 102. The station contains two compressor plants, 'A' and 'B' Each incorporates a gas turbine driven centrifugal compressor unit. 'A' Plant uses an aero-derived gas generator (jet engine) rated at 15 MW (19,000 HP).

Jan 1, 1997

By Charles H. Dowding

Whenever piling vibrations are significant, construction activities associated with pile driving and/or excavation can produce permanent displacement. These permanent displacements are more detrimental to structural performance than the hair sized, cosmetic, plaster cracks that might be produced by slightly exceeding reasonable vibration controls. Case studies are presented which demonstrate the relative importance of permanent displacements compared to directly produced transient vibration displacement within a horizontal distance of one pile length. Special attention is paid to settlements produced by densification of liquefiable sands. SOURCES OF TRANSIENT AND PERMANENT DEFORMATION DURING CONSTRUCTION Confusion over multiple sources of facility deformation caused by adjacent construction complicates the discussion of the relative importance of vibration induced cracking. None of the recent scientific investigations of vibration induced cracking (Siskind et el, 1980), involved deformation other than that produced by ground vibration from rock blasting. Thus these studies carry the implicit assumption that no ground deformation occurred other than that produced by the transient vibration. In other words there is no permanent deformation other than that which is typical of the older residential structures investigated.

Jan 1, 1991

By Charbel Khoury, Kwabena Ofori-Awuah, Kofi B. Acheampong

"Following heavy rains in spring of 2014, Prince George’s County officials issued a mandatory evacuation for homes in the Piscataway Hills subdivision of Fort Washington, Maryland where a landslide along a 1700-foot hillside destabilized homes, collapsed the single access road, and resulted in water and sewer mains break. Forensic investigations, including geologic assessments, test borings and in-situ Cone Penetrometer and Dilatometer soundings, were performed to evaluate subsurface conditions and provide stabilization options for the roadway and slopes. Post-failure ground movements were monitored using inclinometers. Critical failure planes were identified within the underlying 30-foot thick Marlboro Clay formation, a known geologic hazard with historic occurrences of landslides and slope failures.This paper discusses the remedial design for stabilizing the landslide and 60-foot hillside slope failure, and protecting the roadway. Amongst several feasible options, driven piles were selected in consultation with the County and retained contractor based on cost, environmental impacts and site constraints. Constraints included private ownership of hillside slope, upslope buildings safety; deep-seated failure, relocation of underground water and sewer mains, and accelerated construction schedule.Pile design included global slope stability analyses and lateral pile analyses using several loading configurations to optimize pile geometry and spacing, and determine a value-engineered design satisfying both serviceability and strength limit states to achieve long-term stability with factor of safety of 1.3. Soils within the active landslide plane were assumed to provide no resistance, while soils below the failure plane provided lateral resistance. This stabilization scheme, which extended along the 1700-foot roadway section and toe of hillside slope area, consisted of 410 steel HP16x141 piles in two to three rows driven to depths between 60 and 70 feet below the Marlboro Clay stratum at 5 to 7-foot spacing."

Jan 1, 2017

By Juan J. Campo

The Freeport-McMoRan Main Pass Mine development in the Gulf of Mexico is a complex designed to extract up to 67 million long tons of sulphur over a 40 year period. The initial development includes 15 platforms and 13 bridges located in water depths ranging from 208 to 214 feet, approximately 15 miles east of the Mississippi River Delta. Three additional platforms were designed and installed for the oil and gas development in the complex. Over 110, 000 short tons of steel were required to fabricate the structures. As the sulphur is extracted significant subsidence is predicted over a major portion of complex in the shape of a very large bowl. Vertical elevations are predicted to change as much as 65 feet. Horizontal movements and mudline slope changes cause adjacent platform decks to move as much as 30 feet relative to each other. Differential soil movement is predicted between piling of individual platforms causing the piling to spread, resulting in significant lateral loading on the piling. Relative vertical soil movements are predicted along the lengths of the piles which causes "up drag" or "down drag" forces on individual piles. This paper addresses the design of the piling for the structures in the complex. Design criteria will be discussed explaining how the more traditional offshore environmental and gravity loadings were combined with the unique loading caused by subsidence. Design and analysis procedures will be explained and analysis results presented. These results include the incorporation of 100 ksi steel in thicknesses up to 5 inches in some of the tubular piles. Comparisons will be made between conventional offshore structures and these structures designed to accommodate the subsidence.

Jan 1, 1992

By Thomas A. Printz

The wide use of carbon steel in construction and engineering projects makes this engineering material accountable for approximately 85% of the total annual steel production worldwide. Despite the lack of corrosion resistance of carbon steel, it is incorporated into the permanent work for marine applications, power plants, transportation projects, chemical processing, mining, petroleum production and refining, pipelines, mining and construction equipment. Corrosion is an electro-chemical process that occurs in the presence of water and air. When an electric current is introduced to water or soil, the rate of carbon steel corrosion increases rapidly. Gaseous atmospheric constituents that are capable of electrolytic activity can also increase the rate of corrosion. Corrosion tends to be more rapid in environments in which the steel is exposed to water, and then air, rather than being constantly submerged. The exposure to seawater increases steel pitting because the electrical conductivity is improved in salt water.

Jan 1, 2013

By Patrick Bermingham

This report presents the results of six STATNAMIC loading tests that were carried out on four different pile types at the CALTRANS 280 Test Site (Bridge No. 34-46) in conjunction with the Tension Pile Test Program. The STATNAMIC testing was performed by Berminghammer Corporation at the request of the California Department of Transportation, Office of Geotechnical Engineering. Others performed the static tension (uplift) and compression loading tests which werecarried out on the piles tested using the STATNAMIC method. A summary of the STATNAMIC test results is presented and discussed, and the appropriate results are compared with the static test results

Jan 1, 1993

By Kanchan K. Sen

The North Shore Connector (NSC) project will extend the Allegheny County Port Authority?s Light Rail Transit System from downtown Pittsburgh below the Allegheny River to the North Shore via twin bore tunnels. Jet grouting, diaphragm walls, and soil mixing were selected as cost-effective technically viable ground improvement and support of excavation techniques. Jet grouting was specified to provide break-out (egress) and break-in (ingress) block sections at the tunnel boring machine (TBM) launching and receiving pits. Jet grout treatment was also used adjacent to buildings with shallow foundations and below retaining walls along the tunnel alignment. A new method for measuring jet grout column diameter based on electrical resistivity was employed on the project. New equipment was introduced in the U.S for constructing soil mix temporary support of excavation using a soil-mix technique termed Cutter Soil Mixing (CSM) due to the use of two vertical cutting wheels that have evolved from diaphragm wall trench cutter technology. The system allows for continuous water tight soil mix panel construction including steel beams. This paper highlights some applications of jet grouting and various support of excavation systems (e.g. slurry walls, cement bentonite walls and CSM walls), including new innovative techniques (e.g. Cyljet and CSM) used under the constraints of an urban environment.

Jan 1, 2010

By Emilie Lapointe, Fernando Famania

"A reliable determination of the in-placed cement factor, as defined by mass of cement over volume of final element of treated soil, allows the optimization of cement usage to achieve treated soil requirements. Cement determination tests were performed on soil-cement samples, both fresh (as per ASTM D5982) and hardened (as per ASTM C1084). This paper reviews the calibration work required for the D5982 determination of cement content by the heat of hydration method used on soil-cement samples obtained by wet-grabbing. Using the correlation curves in the field provides a rapid assessment of cement content hence optimizing the cement injection rate to match laboratory tests previously conducted. Cement determination tests on hardened soil-cement specimens from wet-grabs and cores were performed using the oxides method. Samples, both cored and wet-grabbed, were tested in a given cement-treated element, and in different soils to inform on the expected variation in cement content from field installation. Results indicate that both cement determination methods are valid for forensically determining cement contents and that they provide better assessment than the conventional field reporting methods. The methods can be used to optimise the cement usage as well as for Quality Assurance, especially when coring quality is poor.INTRODUCTIONThe degree of improvement, and inherent strength, which is attained in a deep-mixed soil is a function of many factors. The binder type, the existing soil, the mixing conditions and the curing conditions are the categories of factors influencing the strength of a given cement-treated soil as agreed by the deep mixing community and as summarized by the Coastal Development of Technology [CDIT] (2012). Given a site with existing soils and conditions requiring soil improvement using a given binder, the designer and/or contractor can control the mixing conditions. Mixing conditions are inclusive of the degree of mixing, mixing duration and the quantity of binder. Once a deep mixing method has been chosen to mix optimally the in-situ soil, the quantity of binder is the only remaining factor to be optimized. The quantity of binder, in the construction industry is commonly referred to as the field binder factor [ar] and defined by the mass of binder over the volume of soil treated with kg/m3 as unit. In research, the quantity of binder is referred to as the binder content [Cc] and expressed as a ratio of the mass of binder over the mass of dry soil mixed."

Jan 1, 2015

By Carole L. B. Mitchell

The South 180th Street Grade Separation underpass in Tukwila and Renton, Washington, USA, permits vehicular traffic to pass beneath Burlington Northern Santa Fe and Union Pacific railroad tracks. The railroad tracks were temporarily relocated onto a shoofly crossing while the permanent bridges were constructed. The maximum underpass depth is approximately 25 feet (7.6 meters [m]). The majority of the sidewalls are supported using alternating reinforced and unreinforced secant pile walls. Temporary and permanent struts brace the top of the excavation. Because the groundwater is about 15 feet (4.6 m) above the base of the excavation and the subsurface materials are loose to medium dense fill, alluvium, and soft flood plain organics, the base of the excavation was strengthened and sealed using wet cement deep soil mixing (CDSM) methods. During construction, CDSM-treated ground temporarily acted as part of the railroad shoofly shoring while the remainder of the underpass was excavated on either side of active railroad tracks. The combination of secant pile sidewalls and CDSM bottom seal allowed for easy excavation, even during wet conditions. Using a 35-foot-thick (maximum) (10.7-m) CDSM layer both to act as a bottom seal and to resist uplift pressures is a unique, dual-purpose application of CDSM technology in the United States.

Jan 1, 2004

By Seth H. Hamblin, John E. Regan, Dimitrios Palantzas

"Through reliability-based calibration of larger pile load test databases, recent developments of the Load Resistance Factor Design (LRFD) methods, which include geotechnical load and resistance factors for deep foundations design, have advanced the state of practice for geotechnical engineering. These load test databases upon which the current geotechnical load and resistance factors have been developed are limited, however, and do not provide sufficient data to support the development of resistance factors for uplift (tension) pile capacity. As such, some recommended resistance factors for uplift capacity estimation methods are simply derived by reducing the recommended resistance factors for piles in compression by a factor of 0.10.The results of three (3) tension loading tests performed to failure on 508 mm (20- in) square precast, prestressed concrete piles, driven though granular soil in southeastern Massachusetts, are presented and compared to static pile capacity calculations and dynamic analyses performed using the Pile Driving Analyzer (PDA) during installation. These results are presented along with current recommended LRFD resistance factors for driven piles under uplift (tension) loading conditions. These comparisons offer an assessment of the applicability and limitations of current resistance factors methods for piles under uplift loading and may be useful additions to the existing database for future calibrations of LRFD resistance factors for driven prestressed concrete piles in sand.IntroductionIn 2010, two (2) natural draft cooling towers were constructed by Kiewit (Kiewit) Construction Company of Woodcliff Lake, New Jersey at the Brayton Point Power Station in Somerset, Massachusetts. These massive 500 foot tall, 400 foot diameter cooling towers were designed to convert the existing “open loop” system into a “closed loop system” thereby dramatically reducing the thermal impact to Mt. Hope Bay.Based on design guidance from the German VBG Design Code and the Massachusetts State Building Code (MSBC), tension (i.e. uplift) and lateral loads due to wind loads and design seismic events represented the critical loading conditions.Weighing approximately 190,000 kips upon completion, the cooling tower loads are transferred to 44 foundation nodes (i.e. pile caps) evenly spaced along ring beams which run the circular perimeter of each tower base. Each pile cap node was designed to resist a 2,000 ton compression load, 200 tons in tension (i.e. uplift), and 600 tons in the lateral direction."

Jan 1, 2015

By Alexander Nikolic

The paper presents the foundation design and construction of a landmark urban redevelopment scheme in central London, UK. The scheme comprises the new Tottenham Court Road Underground station, Crossrail interchange box and associated over-site commercial development. The paper focuses on the design, procurement and construction of large diameter bored piles, up to 68m in depth, which form the foundation support system for the over-site commercial development at Denmark Place. The congestion below ground required an intricate foundation design solution which has been a catalyst for developing innovative load transfer arrangements and has resulted in the advancement of pile construction technology in the UK. The foundation system was also designed to cater for the construction of two significant elements of proposed below ground infrastructure. Selected large diameter piles have been constructed within 1.1m of live underground railway tunnels. An innovative D-shaped pile was constructed in a zone subject to particular spatial constraints. The proposed Crossrail tunnels will be bored within 1m of selected over-site development piles. In addition, a 30m deep excavation forming a new escalator box will be constructed in direct contact with the over-site development piles. The stakeholder engagement process is described together with the foundation design development and buildability assessment. The benefits from early collaboration between the designers and specialist contractors are highlighted. From an analytical design perspective, the entire foundation construction sequence was modelled in detail in order to assess the soil structure interaction and any potential adverse effects on existing elements of underground infrastructure. The results from the three dimensional numerical modelling simulation are compared with field monitoring data.

Jan 1, 2011

By David C. Kraft

A major manufacturer and user of machine tools had the need to install a screw press machine at its plant site with the following design load requirements: (1) Vertical Compression Live Load = 2000 kip (8896 kN) and Dead Load = 1000 kip (4448 kN), (2) Rotational Moment = 6600 ft-kip (8950 kN'm). The screw press machine was to be located within an existing manufacturing building. The bottom of the footing base was located 15 ft (4.6 m) below existing floor slab. A geotechnical investigation of the site indicated a 17 ft (5.2 m) thick initial stratum of stiff to very stiff clay underlain by a 14 ft (4.3 m) thick stratum of loose to medium dense sand. Beneath the sand stratum was soft rock described as weathered shale. Obvious concern was raised on the possible effects of the dynamic motion of the screw press and potential resulting settlement within the loose sand stratum. This combination of large loads and dynamic motion resulted in the selection of a helical pile and tieback system to support the concrete foundation. The helical pile foundation system consisted of a group of vertical helical piles installed into the shale rock and a group of inclined helical tiebacks set into the remaining portion of the clay stratum. Four load tests were conducted on the vertical helical piles in order to establish compression load capacity. The results of these load tests as reported herein, led to the addition of a limited number of tubular steel push piles in order to meet the project required Factor of Safety on the design loads. All of the helical piles, push piles and inclined helical tiebacks were successfully installed and the screw press is now installed and operational.

Jan 1, 2003

By Tatsunori Matsumoto

In order to investigate the variation of the load-displacement relations of piles in a site, vertical load tests were carried out on 25 small diameter steel pipe piles. Out of 25 piles, 15 piles were close-ended pipe piles attached with a blade at the pile toe and 10 piles were open-ended pipe piles. To carry out these load tests in a short period, two types of rapid load test methods, Spring hammer load test and Falling mass load test, were employed. The load tests of all piles were completed in two days with 180 blows in total. In order to estimate a static load-displacement of a pile, non-linear damping method was used. It is shown from the test results that the performance of the pipe piles such as the ultimate pile resistance and the initial pile head stiffness is improved by re-driving.

Jan 1, 2006

By V. M. Troughton

Further pile load testing has been carried out at Canary Wharf to compare the performance of base grouted and ungrouted bored piles founded in the Thanet Sand. The testing regime included three preliminary test piles and two working test piles. The results of these tests are summarised in Table 1 below. Two of the preliminary test piles were located only 14m apart to compare the performance of a base grouted and ungrouted pile in similar ground conditions. The load/settlement behaviour of these two preliminary test piles are compared on Figure 1. All the piles were drilled under bentonite with a drilling bucket. In the base grouted piles four grouting tubes were placed with the reinforcement cage to within 500mm of the pile toe. After the pile had been concreted these grouting tubes were then extended to the pile base by drilling and packers were installed. Grout was then injected into the four tubes simultaneously.

Jan 1, 1991