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By Cassandra A. Wetzel

"Rock socketed mini-piles are a desirable foundation alternative when design capacity is more than 40 tons and there is limited access. In this case history mini-piles were designed to support between 75 and 200 kips at 12 locations adjacent to a perimeter wall, a party wall and at cast iron column piers. Limited geotechnical information, low overhead clearance, and active building population tested the creativity of the team to get the piles installed. The key geotechnical concern during installation of the mini-piles was the presence of a glacial till layer above the bedrock surface that restricted the seating of the casing into bedrock with a track mounted drill rig. Soil loss during the advancement of the rock socket using an air hammer was excessive and increased the risk of subsidence. Over a three week period the engineer worked with the contractor to modify the design, means, methods, and materials to install piles with adequate load capacity. This paper will present the changes in design and construction methods that were required.INTRODUCTIONRock-socketed mini-piles are a common and desirable deep foundation alternative to support loads more than 40 tons in New York City. Limited vertical clearance, accessibility, vibration control, and load capacity make this pile type attractive; it also does not require a static axial load test when socketed into rock. This added benefit makes this alternative all the more feasible.The installation of a drilled pipe extending to bedrock through a glacial till deposit presented challenges to the contractor and engineers to confirm the casing is seated sufficiently into the rock prior to drilling the rock socket. The loss of soil between the steel pipe and the till/bedrock interface can compromise the performance of the pile and soil loss can result in settlement of the ground surface.This paper presents the design and construction method changes made on one project during the installation of ten limited access rock socketed mini-piles."

Jan 1, 2017

By David A. Hart, Barry P. Osborn, Richard J. Totty, Ana T. Carvalho, Max B. Elliott

This paper addresses the experience designing and installing bored piles for the King’s Cross area. This includes continuous flight auger and rotary bored piles, with a range of diameters between 600 mm and 1200 mm, reaching a maximum depth of 56 m below ground level. Existing Network Rail Thameslink twin bored running tunnels are located directly beneath the subject plots. These tunnels have an external diameter of 6.6 m and the crowns of the tunnels are very shallow, in some cases just 10 m below the existing ground level. Some plots needed piles to be installed in close proximity to the tunnels, which required additional control measures and contingency plans. Pile verticality was monitored as the tip of each pile advanced and in-tunnel monitoring readings were verified and are presented. Lessons learned from designing, installing and testing the piles and monitoring the tunnels are addressed in this paper.

May 1, 2022

By Rouzbeh Afsharhasani, Moses Karakouzian, Brandon Kluzniak

"The Vegas High Roller is the centerpiece of a new development parcel adjacent to the Las Vegas Strip. At a height of 550 feet, the High Roller is currently the tallest observation wheel in the world. The design team conducted a geotechnical site investigation to characterize the alluvial soils and cemented layers encountered and to provide foundation design recommendations for the observation wheel, boarding platform, and temporary structures needed to erect the wheel structure. This paper presents a case history of the geotechnical design process, including development of a ground model and design parameters, high-strain dynamic axial load tests, and settlement monitoring during construction. Results indicated that design parameters were conservatively assumed and that the majority of the axial load was transferred to a near surface caliche layer, thereby resulting in insignificant settlement of the foundation system.IntroductionThe engineering of the Vegas High Roller is similar in concept to that of the London Eye and the Singapore Flyer. The wheel has 28 cabins, each with a capacity of 40 persons. The top point of the structure is 550 ft above ground level at the site.A geotechnical site investigation program was undertaken and subsequent analyses were performed to provide foundation recommendations for the observation wheel legs, boarding platform columns, and temporary structures directly associated with construction of the observation wheel."

Jan 1, 2017

By Ali Bouafia

Five full-scale horizontal loading tests of piles carried out by the LCPC in France are interpreted in order to analyse P-Y load-transfer curves. The experimental piles are either bored or jacked into quite homogenous sandy soils and instrumented by strain gauges for measuring bending moments along the pile. Successive differentiation and integration of bending moment profiles have led to derive respectively lateral soil reaction and displacements then to construct the load-transfer P-Y curves. The initial horizontal lateral reaction modulus was derived from these curves and shows linear variation with depth in accordance with Gibson soils profiles. P-Y curves are validated by back-computation of the pile on the basis de these curves and the horizontal reaction modulus was compared to the recommendations frequently used in pile design practice.

Jan 1, 2002

By K. Viking

It's well known that conventional impact hammers, usually are the method to use in order to drive precast prestressed concrete piles. However sometimes the vibratory technique might be considered as a suitable alternative due to favourable soil conditions. It is also well known that piles driven into granular soils can be installed more efficiently by the use of a vibratory driver compared with impact hammers. However, the use of the vibratory technique is seldom regarded as the first choice, since the technique is constrained by several uncertainties related to the pile capacity, and concrete piles to cope with tensile stresses. With the opportunities of having suitable subsurface conditions and a fair amount of piles to be installed, it was anticipated that the use of the vibratory method could result in a significant reduction of the installation costs. Part of the uncertainties of using a vibrator was intended to be eliminated by restriking the vibratory driven pile with an impact hammer and use a Pile Driving Analyzer? (PDA) to correlate recordings of soil resistance to driving with measured rate of penetration, and to evaluate the static capacity and load/settlement characteristics of the vibratory driven pile by conducting static load test. The conducted test study of using a vibrator to drive the precast prestressed test pile (14-in. square by 30-ft-long) did not turn out to the author's complete satisfaction. The present paper focuses mainly on a numerous practical engineering issues in relation to the use of the vibro-technique to drive precast prestressed concrete piles in granular soils. The obtained experiences of using a PDA to monitor vibro-driven piles, with its potential and limitations, is presented and discussed. Furthermore, a simple method of how to subjectively pre-estimate the soil resistance due to vibratory driving is presented and discussed. The reasons for the partly unsuccessful test study are discussed in great detail based on the obtained experiences. Suggestions of how to better approach a similar situation in the future are also provided in great detail

Jan 1, 2004

By Sathya Subramanian, Jun Yuan Ryan Lee, Angelina Yi Tian Theng, Kai En Low, Soon-Hoe Chew, Yeow Chong Tan, Kai Yang Toh, Pei Ling Goh

Conventional Quality Assurance and Quality Control (QA/QC) methods for Cement Bentonite (CB) walls rely on destructive coring, which is carried out at specific curing times like 28 days or 91 days. The key parameters determined are strength and permeability. Hence, the conventional methods will not be able to give any indication on strength and permeability until later stage of curing. This delayed QA/QC hinders quick remediation when unsatisfactory strength or permeability values are obtained. To address this limitation, this study utilizes non-destructive resistivity monitoring system to provide indications of the parameters at early days of curing. By continuously assessing resistivity of CB at various depths, this method aims to provide predictive indicators of long-term strength and permeability, enabling proactive interventions before the conventional 91-day coring, if needed. A comprehensive case study is presented, which includes scaled model in a laboratory, as well as a actual measurement in the field. The large-scale laboratory setup models the actual thickness of the CB wall in the field (0.8 m). Specially designed and fabricated resistivity devices are installed in the laboratory setup, and two sections in the field CB wall. Findings show that in terms of resistivity development with curing time, the field resistivity continuous monitoring data displays a similar trend to those resistivity measurements conducted in the laboratory-scaled model. Cored samples were also taken in the laboratory and field at specific curing time of 91 day. The resistivity correlated well with the cored samples’ strength and permeability values. 

Oct 7, 2024

By George J. Tamaro

The design and construction of foundations in the New York City area are usually dictated by the widely varying geologic conditions encountered in the five boroughs, particularly along the spine of Manhattan Island. Rock extends well above sea level at the northern reaches and falls to depths in excess of 250 m at the barrier islands at the southern extremities. These highly variable geologic conditions, significantly affected by glacial activity, dictate different design and construction approaches throughout the five boroughs of New York City. Extensive rock removal is required at the north while long piling is dictated in the south. Similar changes can occur within a project site on Manhattan Island. This paper will describe these conditions in general, will identify the various solutions used to solve these problems and will summarize various foundation types used in the New York City area.

Jan 1, 2000

By Axel J. Pollak

Since the late 1960's the Interstate Division for Baltimore City (IDBC) has been planning and developing the Interstate Highway System for the city to meet regional planning goals. The principal goals are to provide convenient access to the central business district and the port while diverting through traffic away from these congested areas. Interstate Route 95, an eight-lane highway carrying north-south traffic, has headed the city's priority list; during the 1970's its construction proceeded steadily from both east and west towards the harbor. Closing the final 8800-ft (2670-m) gap under the harbor will complete Interstate 95's construction. This final portion, known as the Ft. McHenry Tunnel project, will be built in nine construction contracts. Construction costs of the complete project are expected to exceed $700 million, making it the costliest single project in the Interstate Highway System. Full funding is being provided initially by the Federal Highway Administration (FHWA), and the Maryland Department of Transportation will re-pay the 10 percent local share from toll receipts within the first three years of operation.

Jan 1, 1989

By D. X. Xu

A pump station was constructed at the food of a steep mountain, very close to a riverside. To protect the pump station from being washed out, and to guarantee the stability of the steep hillside behind the pump station and the safety of the foundation pit when the station was built, cast-in-place R.C. diaphragm walls (Fig. 1) were clesigned in front of and on both sides of the pump station. This wall was 130m long, 0.8m wide and 29m deep. The diaphragm walling on both sides of the pump station served to prevent landslides and to fix anchor piles. The 55m long diaphragm walling in front of the pump station served as a temporary shuttering which kept earth and prevented water from permeating when the pump station was under construction. After the pump station project was finished, static blasting method was used to blow up the wall body which was 10m beneath the ground so that the water from the river could come into the pump station. The remaining wall body below this level was kept to prevent soil from being washed out. [ ]

Jan 1, 2010

By David R. Sutfin, Joseph Lodde

110 N. Carpenter is new commercial building located in the West Loop neighborhood of Chicago, Illinois. The new home to the McDonalds Corporation work headquarters, accelerated project delivery methods were essential to meet the scheduling demands for this project along with other projects slated to start in the region. As such top-down construction methods were utilized to allow for above and below grade construction to proceed in parallel in lieu of more conventional bottom-up construction methods, thus compressing the project schedule. To achieve this plan, perimeter secant pile walls were constructed in conjunction with interior columns/drilled shafts and a shear wall core constructed from inside a temporary cofferdam. The use of secant pile walls allowed for efficient accommodation of a variety of loading conditions including: exterior curtain walls loads, perimeter column loads, tower crane foundation loads, and in-plane shear loads. Furthermore, this system allowed for efficient and fluid operation of equipment on site in order to accommodate the 90-day window allotted for initial foundation construction. INTRODUCTION 110 N. Carpenter is a recently-constructed 9-story commercial building located on the old Harpo Studios property in the West Loop neighborhood of Chicago, IL. The construction of this 55,750m2 (600,000 ft2) structure is significant to the continued commercial development of Chicago as nearly 46,450m2 (500,000 ft2) of the building houses the new world headquarters for the McDonald’s Corporation, which had moved from Chicago to the suburb of Oak Brook in 1971. McDonald’s recommitment to this urban environment is not only a reinvention of the long-established fast food giant but the anchor for a broader redevelopment of the West Loop neighborhood. Since the opening of this building was seen by the developer, the City of Chicago and others as a key to future local projects, innovative solutions were required to showcase forward-thinking design as well as expedite the construction process. The final result of the design/planning process is a structure consisting of nine levels of above-grade commercial space and two levels of below-grade parking, providing approximately 300 parking spaces. The above-grade structure consists of a reinforced concrete flat plate system, including two-way slabs, columns, and two core/shear wall systems for lateral support. With an average depth of 7m (23ft), the below-grade structure consists of interior components similar to the above-grade structure (structural slabs, columns, shear walls) but includes a perimeter secant pile wall that was designed to support lateral earth pressures; vertical forces from the exterior curtain walls, perimeter columns, and the construction tower cranes; and in-plane lateral forces to reduce the demand on and quantity of interior shear walls. The use of a secant pile wall is a key component to the project because it accommodated the use of top-down construction methods to accelerate the construction schedule.

Jan 1, 2019

By Lawrence F. Johnsen, Felix Ferrer, Dino Tomasetti, Cassandra A. Wetzel

"A 17 story building was constructed at the Brooklyn Navy Yard on a site with a long history of development. Most recently the site supported a dewatering well and craneway to service two adjacent drydocks. The subsurface conditions generally consist of the following strata and approximate depths: miscellaneous fill and debris to 20 ft., organic soils to 35 ft., liquefiable sand to 45 ft., varved clay to 65 ft., glacial till to 95 ft. and gneiss bedrock.Hollow core bar piles replaced 18 in. diameter caissons on a 1.67:1 basis. The resulting service loads on the hollow bar piles were 600 kips compression, 21 kips lateral, 180 kips tension and 450 inch-kips moment. The top 30 feet of the hollow bar was cased with a 16 in. x 0.375 in. Grade 50 steel pipe. The piles were socketed 6 feet into bedrock. An extensive load testing program confirmed the axial and lateral load capacities. The paper will also discuss some adjustments to the installation procedure based on the load test program.PROJECTThe hollow bar piles were installed to support a 95,000 sf footprint, 17-story office building at the Brooklyn Navy Yard. The Brooklyn Navy Yard was first developed in the late 1700’s to build merchant vessels. The federal government purchased the old docks and adjoining 40 acres in 1801. The site was an active U. S. Naval Shipyard from 1806 to its decommissioning in 1966. At its peak in World War II it employed 70,000 people, 24 hours a day. Since 1966 the property has been converted to private manufacturing and commercial activity.The site is located between Dry Docks 2 and 3. The adjacent drydocks extend 40 to 43 feet below grade. The drydock walls are restrained by tierods extending back to deadman anchors. The site is also underlain by piles that were installed to support rail lines and a craneway. The building footprint also covered an 85 ft. wide, 70 ft. deep dewatering well which had a thick slab. The structural engineer for the project, ARUP, designed the building to span over the dewatering well.SUBSURFACE CONDITIONSIn September 2014, Langan Engineering conducted a geotechnical engineering study for the project. Figure 1 provides a subsurface profile through the long axis of the site. The general soil profile was very erratic but generally consisted of miscellaneous fill and debris to 20 ft., organic soils to 35 ft., liquefiable sand to 45 ft., varved clay to 65 ft., glacial till to 95 ft. and gneiss bedrock. The fill contained numerous obstructions from the over 200 years of site development. The organic soils were mostly very weak and compressible organic silt. The depths and thicknesses of the varved clay, and sand varied"

Jan 1, 2017

By Ting Chinsu

Diaphragm wall with tie-back cable is widely used for deep excavation, especially in the area with high density of buildings. This paper presents the measured earth pressure distribution on diaphragm wall during excavation. The earth pressure cells used in field were successfully installed in deep slurry trench by a new type of simplified manipulator. The sizes of the deep excavation are 26m X 36m on plane and 9m in depth. The construction site is located between two multistorey buildings at the main business section of Beijing city. In this paper the field measurements of earth pressure distribution and the analyses based on the comparison between calculation and measurement are very valuable to improve the current calculation method for diaphragm wall design.

Jan 1, 1991

By H. Mori

Construction of cast-in-place piles with enlarged bases has become popular in the cities in Japan facing to the sea coast, where the subground soil is soft alluvium deposited to depths often exceeding 30 m. The groundwater table is a few meters below the ground surface. Skin friction of piles may become negative due to ground subsidence or reduced due to liquefaction of loose sand during an earthquake. To support highrise buildings, depths of bearing strata to which piles are embedded often exceed 50 m. Due to such geotechnical conditions, methods and equipment to build cast-in-place concrete piles mainly built by the reverse circulation method have been developed since the 1970s. In the first half of this paper, the authors review the cur-rent practise of building cast-in-place piles with enlarged bases. Then they introduce the TFP system developed in recent years, and discuss about the procedures to control and monitor enlarging of bases.

Jan 1, 1989

By Grischa Dette, Thomas Schröder, Holger Merski

For the construction of the tunnel for the new Berlin S21 light rail line, a construction pit had to be built below the crossing B 96 federal road. For this purpose, the construction pit M’ has been built beforehand as a preliminary structure for the later S21 Berlin. A crucial element of this structure is a 2.50 m deep reinforced concrete deck slab which carries the B 96. During the later construction of the S21, it became clear that the existing preliminary structure could not be used without major modifications. Consequently, the construction pit design was gradually upgraded – still with the aim of retaining the basic concept of a trough structure with a jet-grouting cut-off. As construction progressed, for reasons of stability it became necessary to develop a fundamentally new concept with an underwater concrete base replacing the jet-grouting cutoff. This paper describes the planning and construction of a cut-and-cover structure with an underwater concrete base – a layout that brings with it the difficult task of underwater excavation and concrete placing without direct accessibility from above. Special emphasis is placed on describing the innovative approaches in connection with a remotely controlled underwater dredger from the Norwegian offshore industry for excavation works. Furthermore, the sophisticated underwater technologies for concrete placing in the confined surroundings are described.

May 1, 2022

By Trevor I. Addenbrooke

Stress reducing piles were used for the first time at the Queen Elizabeth II Conference Centre near the Palace of Westminster in London, UK. The inclusion of these piles directly beneath heavily loaded columns was to reduce the high anticipated bending stress in the foundation raft, and to eliminate local yield of the London Clay beneath the column locations. Load cells were placed in one of the stress reducing piles during construction. The data showed that the pile carried about 30% of the column load. This can be contrasted with conventional piled raft design where the pile carries upwards of 80% of the column load. The build up of load on the pile and pile displacement have been accurately reproduced using coupled finite element analysis. These numerical results demonstrate the value of geometrically simple axially symmetric analyses for modelling a pile-enhanced raft. On site, excavation preceded construction of the raft and subsequent pile loading. Failure to model this construction sequence caused the shear strength to mobilize at the base of the pile first, during loading, whereas following the construction sequence caused the shear strength to mobilize at the top of the pile first.

Jan 1, 2002

By Vladimir M. Korolev

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

Jan 1, 2002

By Paul A. O’Brien, Gary A. Chapman, Thomas G. Cuniowski

"The new Amcor B9 paper mill in Botany, NSW, Australia, involved the design and construction of a new paper mill founded within the Botany Basin Sediments. There were numerous design and construction challenges to address, including tight settlement tolerances for the paper machine footings (6 mm total and 1/2000 mm differential limits), high variable and cyclic loads, deep (>25 m) bedrock and uncontrolled fill material across the site. The mill structure design incorporated a deep driven precast and CFA piled foundation solution, with a comprehensive swathe of testing to validate pile capacity and expected settlements. The pile design for the mill structure included the installation of approximately 1000 piles, with pile testing comprising dynamic testing and a static load test on precast piles. With consideration of Sydney’s increasing demand for development space in relative close proximity to the city’s CBD, industrial areas in the Botany Bay area are likely to make way for heavy or complex commercial and residential structures. Therefore, a better understanding of the engineering behaviour of sediments underlying these areas would allow for efficient foundation solutions. This paper presents a discussion on effective foundation testing techniques and the effects that the behaviour and characteristics of the Botany Bay sediments impose on deep piled solutions.2 PROJECT DETAILS2.1 New paper millThe project involved the construction of the largest recycled paper machine in Australia. The paper machine is 330 m (1080 ft) long, 22 m (72 ft) high, and capable of producing 1.6 km (1 mile) of paper per minute. Construction commenced in early 2011 and new paper mill officially opened in early 2013. The early works contract was awarded to Baulderstone Construction Pty. Ltd. (Lend Lease Corp. Ltd.), with the D&C contract awarded to a consortium headed by Leighton Contractors Pty. Ltd. (CPB Contractors Pty. Ltd.), which included Golder Associates Pty. Ltd. as the geotechnical designer and reviewer.2.2 Site history and effect on local topographyThe site has been used as a paper mill since 1902, and as such, has layers of uncontrolled fill and buried objects within the upper fill materials associated with historical industrial use. The fill material generally comprised of loose and very loose sands, with isolated pockets of cohesive materials, peats, pulped paper and general construction waste. In addition, during construction, underground storage tanks were identified at depth, indicating the historical extent of filling across the site was extensive. The presence of this generally uncontrolled fill was a factor for determining that the most cost effective foundation solution for the paper mill was piled foundations, to bypass these materials."

Jan 1, 1900

By Jeffery L. Ottesen

Early construction delays can jeopardize timely completion of subsequent work. As an early construction activity, and due to many unforeseen issues, deep foundation work inherently bears great potential for impacting the critical path of a planned construction schedule. This article describes two construction projects where delays related to deep foundation work forced the Contractor to consider various schedule recovery alternatives to mitigate those delays. Specifically, deep foundations on Vancouver BC's Millennium SkyTrain light rail extension and on a Mill Facility in the United States are discussed. This article cites examples of permitting delays, alleged design changes, differing subsurface conditions and changed construction methodology, the effect each problem had on the project, the mitigation means implemented by the Contractor to minimize adverse impacts of the problem, and Lessons Learned for each scenario.

Jan 1, 2002

By Donald T. Robertson

This paper presents case histories of driven concrete pile damage detected with dynamic testing methods utilizing strain gages and accelerometers embedded in the pile at the prestressing yard during pile construction. Data from the embedded instrumentation is compared with data taken with external bolt on instrumentation and other test methods such as low strain testing on the same pile. In the most severe cases, the piles were extracted revealing and corroborating the embedded data collector results.

By Chengcan Wang, Jin-Tae Han, Young-Eun Jang

"The waveform micropile is a newly developed foundation type for increasing the bearing capacity with the created shear keys on the pile’s shaft. Analyzing the increment of resistance at the shear key zone is a crucial factor in the design of the waveform micropile. Hence, centrifuge tests were carried out employing six different models, including a waveform micropile in the axial loading condition. The analysis results of the load-settlement curves showed that the waveform micropile achieved a higher bearing capacity compared to the micropile without shear keys. In addition, the test results revealed that the load-settlement relationship was affected not only by the pile shape but also by the locations of the shear keysINTRODUCTIONA micropile is a small-diameter pile, typically constructed with a less than 300 mm diameter. Generally, the micropile’s construction involves drilling, grouting, and insertion of a reinforcement material, such as a thread bar. The micopile can be utilized in a variety of fields for reinforcing the foundations of existing structures. It also has advantages for accessing challenging areas like limited-access construction sites, including those with a low headroom space and adjacent structures, due to the small size of the construction equipment. Thus, since it was introduced in 1950 in Italy, the micropile has become one of the preferred solutions when other deep-foundation methods are not applicable to the site.Federal Highway Administration (FHWA) gives the micropile design implementation guideline of neglecting the end bearing due to its small diameter but considering the frictional resistance if the bond zone of the pile is in the soil or on a weak rock. The bearing capacity is considered primarily only if the micropile is founded on a high-quality sound rock (FHWA, 2005). Micropile design in South Korea is currently being performed based on the FHWA manual and taking into consideration the frictional resistance for the design as the pile generally sockets into a weak rock or soft rock. Moreover, the frictional resistance within the soil layer has usually been ignored, considering only the shaft resistance of the rocksocketed length in the conservative design. The design concept excluding the frictional resistance in the soil layer, however, may lead to an extension of the pile socket length, which will increase the construction cost. Hence, many researches have attempted to provide better design and construction methods to increase the bearing capacity in a cost-effective way (Juran et al. 2001; Sadek and Isam 2004; Tsukada et al. 2006; Finno 2002; Gomez et al. 2003; Seo et al. 2013)."

Jan 1, 2016