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By A. K. C. Chan

Recent hotel investment projects in China often involve very tight programmes for design and construction. An example given in this paper involves a 24-storey reinforced concrete hotel tower with 460 bedrooms and a 3-level podium commercial complex. The building is supported by relatively widely spaced columns and shear walls below which 88 number large diameter piers were excavated through fill, silty and bouldery clay on to dolerite and slate at depths between 15 to 3 0m below ground level. Whereas much experience has been accumulated in Hong Kong, hand-excavated pier foundation was only adopted for the first time in Dalian. This paper describes and discusses the various factors influencing the choice of the type and design of the foundation system. The criteria for determining appropriate founding levels are then explained. During installation, revisions to the acceptance procedure were made to cater for local conditions. Emphasis is placed on the role of the geotechnical engineer in making on-site decisions during construction. The advantage of the foundation system in accommodating on-site changes resulting from local complex ground conditions is demonstrated. The pier foundations were successfully completed ahead of programme.

Jan 1, 2010

By Basem Sh. Hazzan

In the last four decades significant effort has been devoted to designing piles in expansive clay soils. Nevertheless, only a scant effort has been devoted to the elimination of heave forces acting on the upper part of lightly loaded piles. For this purpose, an investigation site was established in Karmiel in Northern Israel. On this site sixteen unloaded cast-in-situ piles, both uncoated and coated, were installed in a moderately expansive clay soil in the end of summer 1996. The piles were executed to different depths ranging between 2m and 7m and were observed over a period of 27 months. Another nine unloaded cast-in-situ bored piles were installed at the end of summer 1998 for carrying out pullout tests. These piles were embedded two meters from the ground surface. Results obtained from observations and from full-scale static pull out tests showed that separating the piles from the surrounding clay in the active zone by a twin walled sleeve eliminated the heave forces significantly. The scope of the work is, determining of the elimination degree of the heave forces due to the provision of the above sleeve.

Jan 1, 1999

By Osamu Taki

This paper presents the system, the strength of column, the design concept, and the applications with four case histories from the past project as the general aspect of Geo-Column (trade mark of single soil-cement column by SCC Technology, Inc.). In the system, it shows the installation process and drilling/mixing tool with the mixing process. In the design concept, it shows how to design Geo-Column against the vertical and horizontal load. Finally, it shows the applications with four case histories, (1) building mat foundation, (2) isolated foundation on the pedestrian bridge, (3) bridge spread footing and slope erosion control wall in the channel, and (4) cut-off wall and shoring wall in the underpass roadway to the railroad.

Jan 1, 2000

By J. Nakayama

Down-the-hole hammer is commonly recognized as the most powerful drilling equipment for weathered to fresh rock formation including boulders. However, its drilling diameter is restricted by reasons of difficulty to actualize large diameter drillhead and to ensure discharging means of cuttings. Cuttings are usually removed by flushing i.e. uprising return air after compressed air actuates hammer, but in case of large diameter drilling, as the clearance between drill rod and surrounding wall of hole become fairly large, necessary up-hole air velocity to transport cuttings can not be maintained. In case of marine or underwater drilling or high groundwater table, orthodox down-the-hole hammer is obstructed its operation by water. This single head hammer drill combined large diameter drillhead with reverse circulation of drilling fluid enables large diameter drilling extending to 1.5 m, i.e. actualized large diameter mechanical drillhead incorporated with ensured cuttings removal means enabled this range of drilling. This paper introduces its features and actual applications to large diameter bored pile drilling for varied sorts of rocks in maritime construction projects.

Jan 1, 1996

By M. T. Davisson

Pile compression load capacity prediction methods are divided into four categories for purposes of discussing their reliability compared to static load test results. The categories considered are: 1) static analysis, 2) driving formulas, 3) wave equation analysis, and 4) dynamic measurement and analysis. It is concluded that any method of static analysis that works for the geological deposit in question may be satisfactory. However, any given method can be quite wrong when applied to other deposits of soil that are different in terms of their engineering and geological characteristics. Dynamic formulas are found to be theoretically unjustifiable. The ready availability of the wave equation analysis for microcomputers eliminates the need to utilize dynamic formulas. The wave equation analysis is found to be the best analytical method for making predictions both for design and for construction control. Dynamic methods of measurement and analysis are found useful, but have limitations that have caused troubles on many projects. Two case histories are presented that show the limitations of dynamic measurement and analysis, and of the wave equation analysis. Soil deposits exist that defeat both the wave equation and dynamic measurement techniques; static load tests are currently the only method of proving the load capacity of piles in such soils.

Jan 1, 1991

By Jorj O. Osterberg

The Osterberg (O-Cell) Method makes it possible to separate the side shear resistance (skin friction) from end bearing. The O-Cell is placed on or near the bottom of a drilled shaft and after the concrete is poured and cured, an equal upward and downward pressure is applied. From the test, the load-upward deflection curve in side shear and the load-downward deflection curve in end bearing are drawn. Typical curves are shown where the ultimate load in side-shear is reached and where the ultimate load in end bearing is reached. Several examples of tests in which the test load reached ultimate loads far in excess of what was expected are shown. The side shear in rock sockets is shown to be much larger than generally estimated. Examples are given of where side shear is smaller than expected and the reasons discussed. Disturbance of the sides of drilled holes due to poor construction techniques and ways to avoid these conditions are considered. Examples of bottom hole disturbance are given and ways to prevent the disturbance are discussed. A graph showing the actual measured capacity of drilled shafts compared to the estimated capacity as a function of the hardness and strength of the soil or rock is presented.

Jan 1, 1999

By J. Moskowitz

Construction of the new JFK International Airport Light Rail System (LRS) began in 1998 with a pre-construction load test program. This $1.2 billion design-build project consists of approximately 13 kilometers of elevated twin rail. The elevated rail system is supported on nearly 500 piers requiring deep foundations. The presence of underlying compressible and liquefiable soils as well as space constraints precluded the use of large spread footings. In the 1980's the Port Authority undertook extensive testing to evaluate various piles and drilled shafts types. The LRS piling sub-contractor and the Geotechnical Engineer conducted additional tests for this project to identify the most cost effective deep foundation type. Candidate piles types included: Monotube®, Tapertube®, and closed ended pipe piles. The tapered pile types were found to be the most cost effective and the project utilized both the Monotube® and Tapertube® piles. This paper presents the results of the load test program and the issues related to pile driving induced vibrations and ground movement.

Jan 1, 2000

By Stephan Großwig, Karolina Nycz, Arne Kindler

"Commonly used anchor monitoring systems are mainly based on the use of anchor force meters. However, experience shows that the reliability of the display of force meters lowers over time. Other measurement and test methods like for example fibre bragg grating method require a comparison with an unloaded optical fibre and give only selective information about the bearing behavior. Moreover the obtained information has to be interpreted. In the following article, first measuring results of an anchor monitoring system based on measurements with optical fibre are presented. The new monitoring system is based on the Rayleigh technology and was used to test the load bearing behavior of the anchor grout body as well as for the evaluation of the grout body condition in concrete-damaging groundwater.INTRODUCTIONThe first fibre optic sensors came onto the market about three decades ago. Initially used as special solutions only in selected cases, now they have found use in almost all areas of technology, especially in areas, where electrical sensor systems reach their limits. The first application examples of spatially resolved fibre-optic sensors in the field of geotechnics have been in existence since the mid-1990s, in projects such as the assessment of the of radioactive repository location sites (Hurtig et al. 1994), for the monitoring of landfill sealing systems (Hurtig et al. 1995) or within the framework of the rehabilitation of mountain farming landscapes (Schreck et al. 1998).The company's first own works in the field of glass fibre measurement technology have been in existence since 1993. The first carried out projects were a monitoring at the Edertalsperre (Dietz et al. 2001), a monitoring with glass fibre tendon at a flood bridge in Carinthia as well as monitoring within the framework of the Storebælt crossing. In all cases, the structure was permanently monitored by means of individual-point measurements. Since 1993 various fibre-optic sensor solutions for geotechnical applications have been introduced to the market (Voet, Glötzl 1996, Hurtig et al. 1994)."

Jan 1, 2017

By P. V. Chandramohan

"In ports, piled berths are designed and constructed for berthing of ships with a finite draught. Piles in a bridge foundation also have a large free stand above scoured level. The piles of these structures have to withstand large horizontal forces imparted by the impact of the approaching vessels or due to longitudinal and transverse action in a bridge. It is also imperative that these piles have to project out of the dredged / scoured bed. These piles are normally designed as slender compression members subjected to bending also. They are subjected to vertical load tests for assessing the soil resistance. Lateral load tests, as a rule, are also stipulated. IS and IRC codes stipulate a deflection criteria for lateral load test to arrive at the capacity. These tests are usually conducted on a working pile by jacking out two piles. At the time of the test, pile will be free headed. But in service, piles are fixed head. There is a large difference in deflections between a fixed head and a free headed pile. Besides, a free headed pile will be subjected to a much higher bending moment than the fixed head one. This will put the working test pile under risk of breaking during the test. The problem is analyzed with case studies. INTRODUCTION Vertical capacity of piles is assessed by static formulae. This formula is based on the soil properties obtained from random soil exploration and laboratory and in-situ testing. Since soil is not a homogeneous medium, properties can vary. The design parameters taken for computations may be different from the ones at the interface of the pile with the soil. The best way is to find out is by a load test. The code IRC:78-2014 has rightly stated that initial load test is part of the design process. This is true with the vertical load test. But there are certain problems with the purpose and inference of the lateral load test. In both the tests the criteria for acceptance is the quantum of movement of the point of application of the load. In the former, the movement is vertical and depends more on the compression of the soil than the compressive strain in concrete. But in the latter, this movement is partly on account of the flexural rigidity of the pile and partly due to the horizontal compressibility of the soil. The role of rigidity of the pile is more when compressibility of the soil is higher. Lateral load test is done by jacking one pile against another because it is difficult to get an independent horizontal reaction. Please see Fig.1 Photo."

Jan 1, 2015

By Arpit Parikh

"Ground Water or Pore water pressure development in Sandy Soil formation is Critical situation in foundation analysis and design.Moreover it become severe while associated with higher liquefaction probability in river bank areas. It is difficult to find cost optimized solution for liquefaction mitigation under limited budget allocated for the project. Here in these research paper the attempt has been made to have clear picture of liquefaction by using various techniques and field tests. And its mitigation by suitable foundation type. In Bangladesh, On Bank of River Meghana, Power plant structures are proposed. The particular site is full of fine sand having partial silt throughout from EGL to 55 m depth. Hence in addition to Conventional Boring / Drilling operations, CPLT, SCPT, SCHT and PMT had been performed to arrive deterministic effect of liquefaction. By use of Geologismiki software and some excel based programs developed which indicates that Certainly liquefaction occurs under the event of earthquake. By Checking past records of Bangladesh we found, there are small magnitude earthquakes are inevitable and frequent. Hence fourth to overcome the bad effect of liquefaction, the deep pile foundation -Driven Pre Cast Solid Square Pile of 400 mm dia. had been suggested for various types of power plant structures. Which densify the soil and ground will improve in resisting liquefaction.1. INTRODUCTIONA Detailed Geotechnical/Foundation design Analysis had been done to arrive at optimum foundation design solution in highly probable liquefaction zone of Silty Fine Sand near Dhaka City of Bangladesh for proposed 750 MW Cyclic Power Plant. Hence about 24 no. of (Borehole) Boring and Drilling up to depth of 55 m from existing ground level has been carried out. Additionally, 09 nos. of Static Cone Penetration Test (SCPT), 02 Nos. of Dynamic Cone Penetration Test (DCPT), 02 Nos. of Pressure meter test (PMT), 02 nos. of Cyclic Plate load test (CPLT) of suitable capacity with 06 nos. of Seismic Cross Hole Test (SCHT) in boreholes had been carried out. The purpose of PMT and SCHT was to have clear idea about the Seismic behavior - knowhow of site. According to Basic principles of Soil Mechanics and foundation design, it is proved that PMT & SCHT are dynamic test. These tests stimulate field condition of occurrences of earthquake. In later stages of analysis, it is found that site have high probability of liquefaction through use of Geologismiki – Liquefaction Analysis Software. Author of these research paper also felt earthquake vibrations – strong aftershocks during site study where Epicenter of the earthquake was in Myanmar during month of august 2016."

Jan 1, 2017

By Dennis Nottingham

Spin-fin pipe piles can develop large loads in tension, thus have evolved as a foundation product of great potential. Currently, over 500 spin-fin piles have been used successfully in dolphins, docks, buildings and bulkheads. Spin-fin piles are pipe piles with plates welded near the tip at a batter-in-screw fashion. Thus, as the pile is driven, the pile screws into position. Tests show this pile type to have highly unusual stress/strain relationships, wherein plunging failure is usually never reached either at normal or large deformations. Tension capacity can approach pile capacity in bearing; thus, large reserves are usually available for tension. Tests have been performed on 8-5/8-inch to 24-inch-diameter piles in silt, sand, and gravelly soil, to provide a broad spectrum of data.

Jan 1, 1990

By Martin B. Hudson, Daniel Brescia, Zhangwei Ning

Due to the complexity and sensitivity of surrounding environments, instrumentation and monitoring (I&M) is critical for many urban deep excavations. The objects to be monitored include shoring bulkheads, retained embankments, adjacent buildings and roads as well as underground utilities. However, there are also plenty of constraints on the implementation of I&M such as: congested site space, difficult access to instruments, coordination among multiple contractors, and installation permits for private or public properties. Because of these constraints, sometimes the implementation of the initially planned I&M is delayed, its scope is reduced, and/or the continuity of monitoring is interrupted. For these reasons, it is important to implement the I&M with robust and redundant capabilities while providing minimal interference to the project construction and schedule. This paper describes state-of-the-art I&M technologies including automatic motorized total station (AMTS) with camera and automatic leveling device, reflectorless AMTS and IoT- based wireless sensors based on a case study of an on-going deep excavation project. INTRODUCTION In urban environments, deep excavations requiring the construction of temporary shoring bulkheads are becoming increasingly common, with the associated need to provide protection of the surrounding built environment during construction. Protection of the surrounding environment requires planning, engineering, construction, monitoring, and excessive shoring movement mitigation. The I&M is a vital component of the deep shoring implementation. In public projects, geotechnical I&M is often placed within the general contractor’s scope, whereas the majority of deep excavations are privately undertaken. For those private developments, sometimes the developer contracts the geotechnical I&M directly with the project geotechnical engineer or by a geotechnical I&M specialist hired by the project geotechnical engineer. In either the public project or private development case, the effective deployment of the I&M system relies heavily on coordination and collaboration with the project contractor.

Jan 1, 2018

By Philip Dubbeling

Conventional dynamic sheetpiling techniques are ill-suited to urban development because of the emission of excessive noise and ground vibrations. Drilled shafts and slurry walls alleviate some of these environmental concerns but add additional problems due to large bulky machines, reliance on dusty concrete plants and urban trucking grief. To solve these problems, pre-fabricated sheetpiles are hydraulically jacked-in by reaction principle using a compact and lightweight press-in machine, a so called the "Silent Piler". Through scientific analysis, definition and systemization of press-in machines and methods, new construction concepts such as the one-step approach, implant structures, functional design and life cycle design have been developed to comply with new basic construction principles.

Jan 1, 2006

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 Emre Biringen

Over the past decades, there has been an increasing recognition of the strategic use of pile-supported rafts in design of heavily-loaded structures to reduce total and differential settlements. However, such a hybrid foundation construction method has not been widely utilized in many countries, including the U.S., due to code limitations. In current practice, the foundation design is based on either (i) the bearing capacity of the raft supported by the subgrade soils, or (ii) solely the pile capacity. This paper addresses the potential use of such hybrid piled-raft systems, where the structural load is shared by both by the piles and the subgrade soils directly beneath the raft, in foundation design of power plant structures. The study assessed some of the characteristics of piled-raft behavior by undertaking three-dimensional finite element analyses of two raft sizes, and various pile layout patterns, including the rafts with piles distributed evenly and only in the central area of the raft. The computer software PLAXIS 3D with the Mohr-Coulomb constitutive soil model was used to facilitate the modeling of such cases. The results presented in this paper indicate how strategically locating the piles could reduce the differential and total settlements.

By Magnus Ruin

The dry deep mixing method for stabilization of soft soil has been used in the Scandinavian countries for 25 years. The typical application has been stabilization of soft inorganic clay. Today the method is used more frequently in organic soil with good results. The Limix System, introduced in the USA by Hercules Grundläggning AB and TREVIICOS Corporation, is a cost-effective dry deep mixing method used to stabilize most types of soft soil. This paper presents the general principles of stabilizing organic soil with the dry mix method and two case histories of soil stabilization projects in organic soil. Between October 2000 and June 2001 the Limix System was used in England to stabilize soft organic alluvium at the Channel Tunnel Rail Link, Contract 440. During year 2000 the Limix System was used in soft organic soil in Holland near the Groene Hart Tunnel entrance to support trench excavations for slurry walls and concrete barrettes.

Jan 1, 2001

By Reda M. Bakeer

"Measurements obtained during load testing of two steel H-piles driven at a site in Northeastern Mississippi are discussed. The general site conditions, equipment used, testing procedures and results of the pile load tests are presented. Both piles were tested in compression and one of the piles was subsequently tested in tension. The piles were instrumented with strain gauges and extensometers to measure the mobilized soil resistance and pile movement. Three different “zero strain” conditions were used to determine the mobilized soil resistance and residual loads due to driving or a load cycle. It was concluded that the effect of residual loads on driven piles could be significant. Driving residual loads influenced the magnitude and distribution of the load transfer curves more than those due to a load cycle. Results of the tension test were impacted by the residual loads from the previous compression test performed on the same pile.INTRODUCTIONSeveral factors affect the performance of a deep foundation system including the subsoil conditions, loading settings, pile type and installation method. Residual stresses develop in piles particularly due to pile driving, but they are typically not accounted for in the analysis (Fellenius 2002). Siegel and McGillivray (2009) presented an assessment of residual loads measured during load testing of instrumented auger-cast-in-place (ACIP) piles. The magnitude and distribution of residual stresses along the pile shaft and toe depend on the pile installation method, previous load cycles and time effects. Poulos (1987) reported that residual load due to driving at the pile toe is independent of pile driving equipment and may significantly affect the results of a pile load test. Hunter and Davisson (1969) reported results of pile load tests performed in compression on fully instrumented piles driven in cohesionless soils along with a discussion of the effects of residual loads. Tension loads of about 445 kN (100 kips) were measured at the pile toe after driving. Unloading residual compression load at the toe was detected as “apparent” tension since the instrumentation was zeroed prior to the test. The researchers suggested a graphical approach to obtain the “corrected” load distribution curves considering that residual load will dissipate following the tension test. Holloway et al. (1975) conducted a study on the effect of residual stresses due to pile driving and developed a computer software that accounts for residual loads. Briaud and Tucker (1984) suggested a method to account for residual loads based on the results of 33 pile load tests performed in mostly cohesionless soils."

Jan 1, 2017

By Franklin M. Grynkewicz

As part of the Boston Harbor clean up project, the new 1,000 mgd Deer Island Sewerage treatment plant includes ten 240 feet high egg-shaped "residuals" tanks. Contract documents called for these structures to be supported on 2,600 sixteen inch concrete filled pipe piles. The project site is underlain by highly variable glacial and marine deposits. Subsurface conditions vary from one extreme where firm glacial deposits exist at subgrade to the other extreme where 70 feet of medium stiff clays overlying weathered bedrock must be dealt with. The most common profile consisted of 15-20 feet of sands, 20-40 feet of marine clays, and 20-60 feet of stratified glacial deposits (commonly called tills) overlying Argillitic bedrock. Post bid redesign work, initiated as a cooperative effort between the owner and the general contractor, demonstrated that an $8 million savings could be realized if high capacity 48 inch diameter caissons replaced the specified pipe piles. A highly unusual arrangement of having the general contractor and specialty subcontractor providing input to the owner's engineering team allowed the redesign work to proceed on a "fast-track" schedule.

Jan 1, 1992

By Mohab Sabry, Emre Biringen

"Over the past decades, there has been an increasing recognition of the strategic use of pile-supported rafts in design of heavily-loaded structures to reduce total and differential settlements. However, such a hybrid foundation construction method has not been widely utilized in many countries, including the U.S., due to code limitations. In current practice, the foundation design is based on either (i) the bearing capacity of the raft supported by the subgrade soils, or (ii) solely the pile capacity. This paper addresses the potential use of such hybrid piled-raft systems, where the structural load is shared by both by the piles and the subgrade soils directly beneath the raft, in foundation design of power plant structures. The study assessed some of the characteristics of piled-raft behavior by undertaking three-dimensional finite element analyses of two raft sizes, and various pile layout patterns, including the rafts with piles distributed evenly and only in the central area of the raft. The computer software PLAXIS 3D with the Mohr-Coulomb constitutive soil model was used to facilitate the modeling of such cases. The results presented in this paper indicate how strategically locating the piles could reduce the differential and total settlements.INTRODUCTIONUnder the high applied loads coming from the superstructure, the addition of piles is primarily required to improve the factor of safety against failure when a raft does not provide adequate bearing capacity. If the bearing capacity of the raft is sufficient to carry the total load with a reasonable safety margin, then the addition of piles is usually intended to reduce the settlements to an acceptable amount. In current practice, the design process for pile-supported raft foundations conservatively concentrates on providing solely the pile capacity to carry the total structural load without taking the contribution of the raft into account. This paper addresses the potential use of hybrid piled-rafts in controlling foundation settlement of power plant structures by considering the support of both the piles and the subgrade soils beneath the raft to carry the load."

Jan 1, 2017

By Gordon] [Reavis

Halliburton Services and Brown & Root have developed a unique foundation system that blends oilfield and construction technologies to construct deep foundations which offer significant advantages across a variety of soil profiles. This highly efficient system is being developed to meet the construction industry's needs into the 21st Century. Based on a concept initially introduced to Halliburton Services by V.L. Schellhorn in 1987, Halliburton combined their existing cement slurry mixing and pumping technology with oilfield drilling practices and a new tool design to field test the viability of the concept. Results looked encouraging, and Halliburton asked it's sister company, Brown & Root to evaluate and further develop the process. With Brown & Root's knowledge of the construction industry, the original concept has developed into a viable and efficient foundation construction system.

Jan 1, 1993