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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 A. Eslami

In recent development of piled raft design, the contribution of both raft and piles to tolerate the loads is taken into account, depending on the stiffness and contributions of involved elements i.e.; piles, raft and surrounding soil. The piles are usually required not to ensure the overall stability of the foundation but to act as settlement reducers. One alternative method of foundation design is therefore to introduce piles purely as a means of improving or enhancing the stiffness of the base soil by structurally disconnecting the piles from the raft. In this paper, two and three dimensional finite element analysis of disconnected pile-raft systems are performed on three case studies including a 12-storey residential building in Iran, a 39-storey twin tower in Indonesia, and the 256m height of Messeturm tower in Frankfurt, Germany. The analysis include different geometrical parameters, e.g., pile spacing and embedment length, arrangement and raft thickness for foundation system to obtain the optimized design functions and to clarify the role of each parameter and method of analysis. The parametric study results and comparison to a few field measurements indicate that by concentrating the piles in the central area of the raft foundation leads to the optimum design with the minimum total length of piles. This achievement can be considered as a criterion for project cost efficiency. On the other hand, disconnected piled-raft systems can significantly reduce the settlements and raft internal bending moments. Finally, the comparison indicates that simple and faster 2D analysis has almost the identical results to 3D analysis which is complicated and time consuming.

Jan 1, 2008

By Yeruva Ramanareddy, Sohail Wajid, Ahmed Shaz, K. Bhavani

"CP-06 is an NATM cross passage which connects up-line and down-line metro tunnels near Kilpauk Medical College, Chennai. It lies completely in loose silty sand to dense sand with water table almost touching the ground surface after Chennai floods. Pre-grouting was done before excavation to seal the area and to ensure no-loose pockets. The heading was excavated successfully but while benching excavation huge water ingress started seeping out. Sand also permeated along with water which became unstoppable due to cavity formation and caused the up-line tunnel to sink considerably. A large grouting exercise was carried out with different grout materials and techniques both from the ground surface and inside of tunnel to stop the water ingress and stabilize the tunnel. This paper describes the chronology of events that occurred in the tunnel during CP-06 issue. It elaborates all the different grouting techniques involved in the whole process of the tunnel stabilization. It includes a finite element analysis using Rocscience RS2 9.0 software showing the possible cause of sand incursion with water from the CP invert which lead to the tunnel settlement. This paper also describes the after effects and the lesson learnt from the whole incident.INTRODUCTIONConstruction of Metro Rails has become the latest alternative to cope up with the transportation demand of the growing urban cities population. L&T SUCG JV constructed Chennai Rail Metro Phase II Contract UAA-04 which included design and construction of approximately 4 km of route length of underground mass transit railway including 3 underground stations. This package also includes 12 cross passages which are NATM tunnels connecting upline and down-line side of TBM tunnel for safe evacuation of passengers in case of emergency. As per NFPA guidelines, this is a mandatory structure and there should be atleast one cross passage in 244m tunnel length.CP-06 is a cross passage connecting upline and downline tunnel between Pachiyappa College Station and KMC Station, in Chennai Metro. During the construction of CP-06, heavy water seepage of around 450 liters per minute was encountered during second round of benching excavation after full heading was excavated. An inflow of around 12-15 cum of sand and silt was also observed inside the tunnel along with the seepage water, which created piping inside the TBM tunnel causing it to settle continuously with time. A huge effort was made to stop the water ingress along with loose sand which was causing the running tunnel to settle, involving all possible grouting methods and temporary support installation."

Jan 1, 2017

By Lee Sieng Kai

This paper presents the result of the analysis of strain-dependent concrete modulus from full-scale static axial compression load tests conducted on more than 200 instrumented cast-in-place barrettes and bored piles over the past 12 years, covering commonly adopted grades of concrete for heavy foundation construction in Malaysia and Singapore. The concrete modulus values, Ec, analysed were directly back-calculated from the material of the instrumented test piles by means of placing a layer of vibrating wire strain gauges near the pile head region. The best fit curve for back-calculated concrete secant modulus versus measured axial strain follows non-linear behaviour for both categories of test pile samples analysed. The result of the analysis seems to suggest that using average constant modulus value would generally lead to a significant error in load distribution computation, particularly at high stresses region.

Jan 1, 2006

By Dawn C. Tattle

[ ] Panoramic View of Completed Facade Supports The following case history describes the installation of earth retention systems, historical facade supports and structural caissons by Anchor Shoring & Caissons Ltd. at the Air Canada Centre/Raptors Stadium Project in Toronto, Ontario, Canada. The Air Canada Centre/Raptors Stadium project includes a 140,000 square foot office tower, a 20,000 seat basketball arena and their support facilities. The arena within the complex will also have the ability to host hockey, ice shows, concerts and family events.

Jan 1, 1997

By N. S. Yet

This paper shall present the design and construction of bored pile and diaphragm wall for the proposed MHA complex in Singapore. The work was carried out by L&M Foundation Specialist Pte Ltd and PWD Consultants Pte Ltd was the consultant for this project. A brief description of the project is first presented to illustrate the scope and scale of the work involved, which includes the construction of bored piles and diaphragm walls and installation of steel stanchions in the bored piles. This is followed by a description of the methodology used to analyse and design the wall and bored piles. As both towers in this project are supported on bored piled foundation and are constructed by top down construction method, the analysis of the wall has taken into consideration the sequence of work phase by phase and this was carried out by means of a commercial finite element program called CRISP. Modelling of the problem will be briefly described and the findings from the numerical analysis will be presented. This is followed by a description of the structural and geotechnical design aspects of bored piles. The paper shall then describe the difficulties encountered for this project and solution used to solve the problem. The subsoil condition will be described with special mention on the encounter of very strong granitic rock at depth above the maximum excavation level of the basement at certain locations, hence necessitating the drilling of rock for a considerable depth for both bored piles and diaphragm wall. At this juncture, the construction method used to drill through the rock will be briefly described. For construction of bored piles, penetration of rock was carried out by chiselling or drilling using reverse circulation rigs. For construction of diaphragm wall, it requires the employment of Bauer hard rock cutter which uses cutting wheels fitted with roller bits and are capable of excavating into granitic rock of compressive strengths more than 100 MPa.

Jan 1, 2000

By Anthony H. Tawil

Modern, high-speed machines used in the manufacture of paper require foundations with stringent settlement constraints. To fulfill this requirement, caisson piles, extending into bedrock, were selected to support a paper machine in Baie Comeau for the Quebec North Shore Paper Company (QNSPCo.). This was the fourth machine in an existing paper mill, and its construction was part of an expansion program which included the building of associated structures such as a wood room and chip storage building, and other facilities, Figure 1. The paper mill in Baie Comeau, Quebec, is located in an area which has extensive deposits of sensitive marine clay which are transformed into a viscous liquid when disturbed by external forces such as the driving of piles. Loss of ground and soil disturbance as affected by piling activity assumed considerable importance in the design and construction of the caissons particularly in view of the proximity of existing plant facilities, including another paper machine.

Jan 1, 1987

By Andy Schroeder

Located in Hamilton, Ontario Canada, Berminghammer Foundation Equipment, is a manufacturer of advanced foundation equipment with 30 years of experience. The company is represented in more than 20 countries world wide, maintains an extensive Research and Development team, and has earned a reputation for finding the most practical solutions to the most challenging projects. The vertical travel lead, referred to as "VTL" system, was first developed and patented by C.W. Bermingham in the 1970's. This lead system was developed in response to the fundamental limitations of either a fixed lead or hanging lead system. The fixed lead system is well suited to level job sites with few obstructions and has the advantage of faster positioning of the lead, the hanging lead is very adaptable to different elevations and batter piles but takes much longer to position. Therefore the Vertical Travel Lead was developed to combine the advantages of fixed leads, fast and accurate positioning, with the ability to adjust the height of the lead base up or down. The VTL lead is connected to the boom by a sliding connection which allows the lead to be elevated or lowered below grade. The advantages of the VTL system were recognized by many foundation specialists and they have become the Industry standard in Canada , US Railway Construction , and many parts of the USA.

Jan 1, 1997

By E. E. De Beer

This paper describes a method for the determination of the settlement of an individual H-bearing pile, based on the results of CPT-tests. As implied by the nature of the problem, no analysis performed on one pile can be regarded as generally valid for a whole piling foundation project because, even on one site, the pile behaviour varies from one pile to another. Consequently, no precise mathematical analysis has been established; the proposed procedure represents a simple model for the determination of the probable settlement behaviour of an H-pile under a compressive load. Prior to the settlement computations, the rupture load and the resistance distribution along the pile have to be determined. Since the method for the determination of the H-pile bearing capacity from the results of CPT tests has been described elsewhere (de Beer, 1971, 72; de Beer et al., 1982; Arbed, 1985), no details will be given in this paper. The proposed method is valid for both uniform and non-uniform H-piles. The computed results have been satisfactorely compared to the static loading tests performed on different types of piles in clayey and sandy soils during an ECSC research program on H-bearing piles (1983-1987).

Jan 1, 1987

By Michael Arnold, Jonathan Delgado

In 2017, Bauer Foundation Corp. (BFC) was awarded the contract to install the deep foundations for the new 17-story Hotel Tower and the Low Rise Casino Expansion at the Seminole Hard Rock Hotel and Casino in Tampa, Florida. The site was underlain by extremely challenging Florida Limestone geology and surrounded by occupied existing buildings and infrastructure. To overcome the challenges of the difficult subsurface conditions, and to successfully complete the foundation installation without impact to the surrounding buildings and casino operation, Langan Engineering (EOR) and BFC were required to modify both the design and installation techniques during construction. The scope of work included 147 temporarily cased drilled shafts to depths up to 230 ft (70 m) below ground surface (BGS), 76 permanently cased micropiles up to 200 ft (61 m) BGS, and more than 300 augered-cast-in-place (ACIP) piles up to 125 ft (38 m) BGS. Voids and zones of high permeability in the limestone created many challenges for execution of the foundation scope including ACIP piles overbreaks of more than 400% above neatline volume, and construction induced ground subsidence/collapses adjacent to structures supported on shallow foundations. This paper will discuss site limitations, design and construction challenges, difficult geology, varied soil conditions, and lessons learned. PROJECT The project is located at Seminole Hard Rock Hotel and Casino Tampa, Florida, as shown in Fig. 1. Seminole Tribe, the owner, started the construction of a new 17-story Hotel Tower and the Low-Rise Casino Expansion at the beginning of 2017.

Jan 1, 2018

By I. H. Wong

The large diameter caisson foundations and their construction methods for three 50 to 60 storey high buildings in Singapore are described. The caissons are 5 m to 8 m in diameter and 40 m to 100 m deep, excavated either by hand or mechanised excavators or by drilling and blasting. Performance of the 50 storey DBS Building is described.

Jan 1, 2010

By A. Mazzucato

This paper presents the experimental results of driving and load tests on an instrumented pile driven into a test pit filled with fine homogeneous sand.

Jan 1, 2010

By Julie Shang, Tim Evans, Michael McDonald, Yu Guo, Bingfeng Xue

Effective chemical grouting represents a technical and economic solution to many challenges related to soil stabilization and blocking the flow of water. Chemical grouts are facing increasing demands in durability, environmental impact and value. To better meet these challenges, a novel and cost effective process was developed to produce a sodium silicate that increases the ratio (i.e. silica to alkali) beyond what has been used in traditional silicate-based grouts. The move to a lower sodium form of silicate was anticipated to have two desirable performance enhancements; a reduction in leachable sodium and improvement in the durability of the silicate grout. An in-depth study was performed at the University of Western Ontario Geotechnical Research Centre to quantify improvement in durability as well as other performance properties such as compressive strength. The study began by first modelling the gelation time and reaction kinetics of the high ratio sodium silicate over a range of silicate concentrations using two different setting agents as well as with/without a hardener. As expected, reducing the level of sodium produced a much more water resistant grout. These same formulations also showed a four order magnitude reduction in permeability. Somewhat surprising, test results showed the higher ratio silicate having much higher compressive strength. At the time of this abstract, the high ratio silicate was moving to the trial stage for geotechnical applications while the petroleum industry was further along with several successful field trials for water blocking as well as cement remediation. This paper will review the chemistry, testing and features of this next generation form of sodium silicate. Introduction Sodium silicate based grouts have been used for decades for soil stabilization and water control. Over the years, several silicate-based systems have been tailored for specific application conditions to maximize performance and reduce cost. Past research has also focused on the selection of setting agents and hardeners for silicate grouts. A constant in the development effort has been the grade of sodium silicate. The vast majority of chemical grouts have been formulated using a ~3.2 ratio sodium silicate. As a very brief overview on the meaning of “ratio” and why it is so important to performance properties. The ratio describes the proportion of sand to alkali or SiO2:Na2O used to make different grades of sodium silicate. Comparing a 2.2 ratio to a 3.2 ratio, it is easier to polymerize and set the 3.2 ratio. Upon setting and forming a silica gel, the system has higher compressive strength values and improved durability with a reduced level of syneresis (i.e. shrinkage). This leads to the question if 3.2 is better than 2.2 why not go to 4.2 or higher?

Jan 1, 2018

By P. A. Neill, O&apos

The caisson foundation for Vent Building No. 6, at the southern landfall of Boston's Third Harbor Tunnel, was installed inside an unbraced concrete cofferdam 250 feet in diameter and about 70 feet deep. As a spectacular engineering feat, the cofferdam itself certainly ranks first. However, the foundation work within was no routine caisson job and made its own contribution to the state of the art. Comprised of 5 ft. diameter caissons socketed 10 to 16 feet in sound rock, it posed serious challenges in logistics, space limitations and time, requiring development of unique, purpose-made equipment. The unexpected discovery of significant depths of shattered rock overlying acceptable sound rock, along with other surprises of lesser import, compounded the problems. How these challenges were planned for, met and overcome is the subject of this paper.

Jan 1, 1994

By Elizabeth M. Smith

The kcICON design-build project in Kansas City, Missouri includes widening the existing roadway, improving interchanges and grade separation bridges, and replacing the Missouri River Bridge. The Missouri Department of Transportation (MoDOT) typically utilizes steel H-piles and steel pipe piles as driven pile support for bridges. After bidding the kcICON project, the cost of steel rose significantly and the design-build contractor used an innovative approach to reduce foundation costs without significantly affecting the project schedule. The kcICON team conducted a value engineering evaluation of alternative foundation types for use at four grade separation structures. The result of the value engineering evaluation was selection of precast, pre-stressed concrete (PPC) piles as the preferred foundation alternative. Terracon developed a test program to evaluate the performance, capacity, and suitability of PPC piles at the site using a PDA and CAPWAP analyses. This paper presents the value engineering design, rationale for selection of PPC piles, results of the pile test program, and findings during production pile driving. The collaborative approach to the project by MoDOT and the kcICON team, combined with testing and a site-specific design approach, resulted in substantial savings for the design-build contractor.

Jan 1, 2009

By Jon H. Gould

This paper describes the following at the new Advanced Solid Rocket Motor (ASRM) nozzle manufacturing facility, which is being constructed inside an existing manufacturing facility: 1) generalized subsurface conditions, 2) pile load test program and evaluation, 3) pile selection, 4) problems associated with pile driving operations, and 5) production pile installation. The poor subsurface conditions, known and unknown underground obstructions, and work environment inside the existing building, used to manufacture the Space Shuttle external fuel tanks, required special pile installation equipment, procedures, and work schedules to install the economical pile foundation system ahead of schedule and without a lost time accident. GEOTECHNICAL STUDIES In April and May 1990, 16 soil test borings were drilled inside the existing building with a truck-mounted drill rig. The borings extended to depths ranging from 60 to 65 ft (18.3 to 19.8 m) below the floor slab. Typically, the silty and clayey soils were sampled by pushing "undisturbed" Shelby tubes, and the more sandy soils were sampled by driving a Standard Penetration Test (SPT) split-spoon sampler. The unconfined compressive strength, water content, and unit weight of the Shelby tube samples were measured in the laboratory. A geotechnical report was issued in May 1990 presenting the results of the field and laboratory testing and foundation recommendations (Gilbert, 1990).

Jan 1, 1992

By K. Viking

The vibratory characteristics of full-scale sheet piles, vibratory driven into the ground, have so far not been described systematically in detail. This paper concerns the preliminary results of a series of full-scale field tests where both the driveability and induced ground vibrations have been continuously monitored. Furthermore, the results of measured ground vibration levels have been measured at two different sites characterised as having hard and easy driving conditions. In the light of the presented results, the paper briefly discusses how the complexity of a driveability and vibration prediction can be subdivided into three parts, namely, vibrator-, sheet pile-, and soil-related parameters, all of which significantly affect both the driveability and induced ground vibrations.

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 R. T. Stain

Integrity testing of deep foundations is now common practice in Europe, indeed in the City of London such testing is a contractural requirement on every site. This paper is in two parts: Part 1 describes the most commonly used test methods and their applications. Part 2 presents a case history where both of the above techniques were used.

Jan 1, 1987

By Thomas Passlick

By means of further developed machines and techniques and with growing experiences in jet grouting, the challenge of this building method becomes more and more complex. To keep the concerning risks as low as possible, the requirements on the quality assurance continuously in­crease. The construction of a 37.0m deep seated slab for the Amsterdam metro station Vijzelgracht in marine clay represents such a complex task. This paper summarises the required measures of quality assurance. In particular a new hydraulic measuring device is introduced with which it was possible to detect the column diameter of 2.6m at a depth of 37.0m during the production process and with a very high accuracy.

Jan 1, 2006