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By Joel Moskowitz

In 1990, the United States General Services Administration (GSA) issued a contract for design and construction of a new federal court building in New York City. Mueser Rutledge Consulting Engineers (MRCE) served as Project Geotechnical Engineers. The project site is in the historic government district at Foley Square. It is surrounded by the New York County Courthouse to the west, an existing federal prison building and federal courthouse across Pearl Street to the south and southwest, an office structure to the north, and a residential tower to the east. The interior of the site was crossed by streets which have now been demapped. As with many urban sites, this site was previously occupied by tenement buildings or industrial structures demolished near the turn of the century. Remains of old building foundations were exposed during construction excavation. In addition, buried fuel oil tanks servicing the adjacent courthouse were removed and the usual assortment of urban utilities had to be relocated for the new building foundations. Ground surface elevations vary from about 4.5 to 6 m above the local Mean High Water Datum Plane.

Jan 1, 1996

By J. Matos e Silva

The paper refers two examples of structures located in seismic areas (Cases 1 and 2). The first one (Case 1) is the Torroal Bridge, located about 100 Km South of Lisbon, in the road Troia-Grandola. The horizontal loads due to the seismic actions were mainly carried by an anchor curtain connected, to the abutments, by reinforced concrete struts-ties. For the some purpose diaphragm walls were also placed under the pile caps of the column foundations. The second one (Case 2) refers to a building located about 50 Km South of Lisbon, at Sesimbra, near a cliff. To reduce the horizontal displacements of the structure due to seismic actions, in order to prevent the endangering of the cliff stability, an anchor curtain was adopted and connected, to the structure, by prestressed anchors.

Jan 1, 1996

By Peter O. Wilkinson

Ascot Racecourse in the UK is a major international venue for horseracing. The racecourse is being redeveloped to provide entirely new public facilities. The development includes the construction of a new grandstand. A site investigation was earned out comprising mainly cone penetration testing. The site is underlain by the Bagshot Formation, comprising predominately cohesionless deposits of medium dense becoming dense, silty fine to medium sand, containing occasional layers of clay. Shallow foundations would present uncertainty regarding total and differential movement; hence a piled foundation solution was chosen using a continuous flight auger (CFA) piling system. The possibility that piles may found either directly on or within the influence of cohesive material suggested uncertainty regarding toe resistance. In order to measure shaft friction, an instrumented preliminary test pile was undertaken. The results were compared to published correlations of cone and shaft resistance. This approach resulted in a net saving in terms of pile length which resulted in optimum value engineering and hence a cost saving to the client.

Jan 1, 2006

By Wei Zheng

A pulverized coal fired power plant is being built in Osceola, Arkansas, along the Mississippi River. The subsurface soil conditions consist of a certain amount of very soft clayey silt and clay underlain with a medium dense sand layer and a dense sand layer. The site has been raised four to five feet with fill material consisting of sand and gravel. Consolidation settlement due to the fill is expected to cause negative shaft resistance (downdrag) on the pile foundations. The site is located in a high seismic hazard area - the New Madrid Seismic Zone (NMSZ). The liquefaction analyses indicated that there is a high liquefaction potential in the medium dense sand layer. Load tests are needed to determine the shaft resistance and the end bearing of each soil layer for design purpose. Two types of pile foundations ? augered pressure grouted displacement pile (APGD) and partial augered pressure grouted displacement pile (P-APGD) were considered for this project. Ten pile load tests, including five compression tests and five tension tests, were performed for three different areas. Strain gauges were installed for the compression tests. The APGD and P-APGD piles were installed side by side for comparison. In addition, three additional dynamic tests were performed to supplement the information from the static load tests. Load deflection curves for the compression tests were predicted, and the failure loads were interpreted using four different methods. The shaft resistance and the end bearing were determined from the strain gauge data and were used to back calculate the ultimate capacity. The back-calculated capacities are in good agreement with the predicted failure loads; they were further verified with the tension load test results.

Jan 1, 2007

By George C. Webb

A wide variety and variable depth (up to 40 ft.) of compressible, uncontrolled fill (including construction debris and a perched water condition) was present at a proposed Kroger construction site in Dent, Ohio. An innovative solution using a combination of an ACIP foundation system with a Tensar geogrid reinforced load distribution platform was used to provide a high quality building pad. This system allowed the use of conventional shallow foundations for structure support. This system was used in lieu of more costly solutions, such as complete undercutting of the entire existing fill and replacement with engineered fill or a deep foundation/ structural slab system. The selected ground modification included a system of augercast piles bearing on shale bedrock, which were installed on a grid pattern over the entire building footprint. Then, three layers of Tensar polypropylene biaxial geogrid were used to create a reinforced soil mat, which was supported on the augercast piles. An eight-foot blanket of engineered fill was placed above the geogrid-reinforced mattress fill to establish the building subgrade elevation. Standard shallow footings and slab-on-grade construction methods were then used to support the 26-ft. tall masonry block building. A small-scale instrumentation program included monitoring the geogrid reinforced mat settlement, geogrid strain and earth pressure distribution under the reinforced mat to evaluate design assumptions and theoretical analyses. This case history describes the first application of a pile supported geogrid reinforced mat for structure support which has been documented in the United States.

Jan 1, 2005

By Barritt Lovelace

Collins Engineers has been researching and implementing the use of drones on Civil Engineering Projects since 2015. Applications include bridge inspection, asset management, mapping, construction site management and emergency response. Recently this technology was used to map and model construction sites with deep foundations to verify and quantify designs. The ability to collect and use large amounts of data is transforming our world. Drone hardware and software is being used to capture and digitally replicate assets, giving owners unprecedented ability to visualize and manage their projects. Our teams help owners collect and process drone data into deliverables to be analyzed, annotated, stored, and shared. The use of drones can transform the way projects are managed and can improve project workflows. Data collected with drones can be processed into a digital twin of any project site or asset. This digital twin provides owners with a three-dimensional geometrically and geospatially accurate model. These models can be annotated and tagged with information that can be stored and shared locally or on cloud-based platforms. The data can be exported and used in a wide variety of CAD and GIS platforms. Goals When considering the use of UAS for several items need to be considered when establishing project goals. Safety Drones can be used to reduce job site safety risks in two ways. The first is that use of the drone can remove personnel from harm’s way. Surveyors and other project staff will traditionally walk the site to collect survey and other site information. These efforts can be replaced with the use of a drone eliminating much of the need for personnel to be on the job site itself which improves safety. The other way safety can be improved is that a digital model of a job site can be created on a daily or weekly basis that can be quickly analyzed for safety hazards. This analysis could be done remotely by safety officers to identify job site hazards which can then be corrected before injuries happen. Improved Deliverables Perhaps the most important reason to incorporate drones into project workflows it the ability to improve the project deliverables. Drones have the ability to quickly collect large amounts of high quality data which can be processed into orthomosaics, point clouds and 3D models that give engineers and project managers the information they need to make better decisions on design or project management.

Jan 1, 2019

By David E. Albus, Bidjan Ghahreman

A single-family home constructed on the side of a slope in Los Angeles, CA, was subjected to lateral forces due to soil slope creep on the pile foundation supporting the home. Impacts to the property included cracking and separations in the street, retaining walls, exterior concrete flatwork, and decorative concrete features in the rear yard area. The home was supported by concrete piles that penetrated the surficial soil mantle and were embedded in underlying bedrock. However, the home exhibited minor distress that suggested even the home was being affected by soil creep. Selected points on the home were monitored with an optical survey method and manometer over a period of two years to assess if the home was undergoing vertical or lateral movement. Monitoring data indicated the home was in fact moving down slope in a manner consistent with slope creep. As a result, the authors were concerned that continued movement due to slope creep could result in over-stressing of the piles that support the home and ultimately lead to failure of the foundation system. An evaluation was then undertaken to evaluate the behavior of the foundation system due to forces from slope creep. Research was performed during the course of evaluating the conditions to consider various approaches to modeling pile behavior of the piles supporting the home. Some research has been performed to field measure creep displacement of soils and rock in slopes. These previous works have found a diverse behavior of the soil displacement with depth (velocity profile) indicating the process is very complex. An example of various velocity profiles measured in field experiments is depicted in Figure 1. Other research focused on theoretical models of velocity profiles and exhibited similarities to some of the field measured cases.

Jan 1, 2018

By Amr M. Sallam

In recent years, with the increase of the number of high-rise buildings that are proposed and being built in Central Florida especially in Downtown Orlando, Augered Pressure Grouted Displacement (APGD) piles became a pronounced foundation option. The APGD pile is a bored displacement pile that does not result in drilling spoil. APGD piles are mostly suited for loose to medium granular soils and slightly silty/clayey sandy materials, such as those encountered in Central Florida. The case history presented in this paper involves the APGD piles recommended for a 35-story mixed-use condominium in Downtown Orlando. The subsoil condition was typical for the region; that is loose to medium fine sands underlain by thin layer of plastic sandy clays and plastic clays followed by mixed clayey sands and sandy clays with phosphates and traces of shells transitioned to the weathered limestone. Four APGD test piles were installed and were, statically, tested. Three of the tested piles failed to support the design load. Analysis of load test results showed that the bottom half of the test piles, below the plastic clay deposits, was not effective, which was attributed to structural deficiency resulted from possible pile necking due, in our opinion, to the increase of the porewater pressure within the plastic clays. Three additional test piles were constructed with modified reinforcement cage; that is to extend beyond the plastic clays with tighter stirrups. The additional test piles were, statnamically, tested and were able to sustain the design loads. The construction of the APGD piles through subsoil conditions similar to those of Downtown Orlando, where plastic clayey deposits are encountered, should account for the high porewater pressures that mostly will be developed within the plastic clay, hence, may cause pile necking. Extending the cage to penetrate through and pass the plastic clays reduced the necking potential and improved the test piles performance.

Jan 1, 2006

By Miklós Kovács

A new type of the cast in situ piles is introduced. The installation of the new pile is based on a pushing in/gaining back procedure. A temporarily closed tip element with square shaped cross-section being attached to an upper circular shaft tube is vibrated into the soil. The steel armature is embedded. Concrete is poured into the tube and, the whole structure is gained back while the tip is in opened position. The width of the tip is less than or equal to 40 cm. The maximum length of the pile is about of 14 m. Great bearing capacity is resulted from the double soil compaction effect. No spoil is generated and, the pile construction can be controlled. The paper presents the results of four loading test at three sites with some soil data.

Jan 1, 2002

By Maurizio Siepi, Bruno Vingiani, Claudio Asioli

"The article describes an emergency rehabilitation intervention executed at Buyo Dam, in Ivory Coast, to intercept a significant water seepage occurring through the foundation of this zoned earthfill retaining structure constructed in the late Seventies. To solve the problem, a 800 mm thick, 400 m long impervious cut-off wall (COW) was constructed on the right side of the embankment, operating from the dam crest and with the reservoir almost at its maximum level. The use of an innovative pre-mixed self-hardening grout, with a target hydraulic conductivity coefficient (k) lower than 10-9 m/s, was considered the only way to match the tight working schedule and the strict requirements for the filling material of the COW.Presentation of the Hydroelectric Scheme of BuyoThe hydroelectric scheme of Buyo, located at 6°14’28” N 7°20’45 W on the Sassandra River, in Ivory Coast (Figure 1), was built in the late Seventies for agriculture and power generation. With a reservoir of 8.3 billion m3 and an installed power capacity of 165 MW, enough to supply electricity to 111,000 homes, it represents an installation of great significance for this West African country."

Jan 1, 2016

By C. M. Haberfield

"1 INTRODUCTION Around the world, there is a demand for larger structures, tall buildings and large bridges. While good footing design is important for all structures, it is even more important in the case of large structures. Recent experience with footing design for tall buildings (e.g. Burj Al Alam development and Nakheel Tower in Dubai, the Gate of Kuwait in Kuwait, the City Centre Project in Bahrain and Eureka Tower and Freshwater Place in Melbourne) has shown the benefits of investing in footing planning, design and construction (Haberfield, 2011, Poulos and Bunce, 2007). The footing systems for most of these projects include the use of deep bored piles or barrettes (piles of rectangular cross-section). Many use piled rafts where the piles, while acting to support the load, are primarily used to reduce settlements. A clear understanding of the factors controlling the behaviour of the footing system is needed to enable a good engineering design to be achieved. This starts with a sound understanding of the ground characteristics and individual pile performance, including adequate collection of data and testing. The best footing solution can then be found using recent improvements in data collection and analytical techniques, complex and highly capable computer-based models and the availability of high speed computers. This paper focuses on the axial performance of deep bored piles socketed into rock – both their individual performance and their performance as part of a larger footing system. Recent research and construction practice is discussed. In practically all cases, serviceability conditions control the behaviour of the footings. Methods of establishing the parameters for input into sophisticated computer programs are described. Application of the methods to case studies is included and it is shown that the behaviour of individual piles can be closely predicted. These developments lead to lower construction costs, better constructability and shortened construction time because of the better understanding of footing behaviour. 2 FACTORS AFFECTING PERFORMANCE OF FOOTINGS ON ROCK For a typical pile-supported footing, it is necessary to consider both individual pile, pile group and raft performance. These require consideration of the behaviour of the ground immediately beneath the surface raft or footing, along the pile shaft, and at and beneath the pile toe (Figure 1). Immediately beneath the surface raft or footing, the important factors are strength for bearing capacity and stiffness for settlement and interaction effects. Along the pile shaft, of most interest are strength for bearing, excavatability and stability; stiffness for settlement and interaction effects; geology and permeability for pile stability and, most importantly, pile shaft resistance. At the pile toe all the above factors for the pile shaft are present and in addition the pile end bearing is of interest. Below the toe, stiffness for pile settlement is important to at least a depth of twice the building width."

Jan 1, 1900

By Z. G. Lin

In Xian, China, compaction by means of soil (or lime-soil) piles is one of the effective methods widely used for densifying loess and eliminating its collapsibility. However, as a result of groundwater table rising, it is no longer applicable in many areas. This paper is the summary of the first-time use in Xian of sand-gravel compaction piles aimed at densifying the miscellaneous fill (already partially under water) and saturated loess at a certain project site. In-situ tests, conducted before and after the treatment and including several kinds of penetration tests backed up and confirmed by a set of plate loading tests, yielded very satisfactory results, strongly testifying to the viability of the method.

Jan 1, 2010

By William F. Anderson

A series of pile load tests (maintained load tests, constant rate of penetration tests at different rates, and statnamic tests) was carried out on an instrumented model pile installed in clay beds prepared by consolidation of a slurry in a calibration chamber. The total load, shaft resistance and end bearing during the pile load tests were investigated. Following this, alternative methods of deriving the static load-settlement curve from a Statnamic test in clay taking into account damping effects have been proposed. These methods have then been used to interpret a statnamic test on a full size instrumented pile installed in a stiff glacial till.

Jan 1, 2006

By Vasileios A. Drosos

The response of pile foundations to lateral loads is an important factor for the successful performance of several critical structures. A new numerical code for the analysis of single piles under lateral load is outlined. The code can simulate (through appropriately chosen parameter values) not only the non-linear behavior of soil, but also the inelastic structural response of the pile itself under lateral load. Emphasis is given on the calibration of model parameters and the verification of the code. For the calibration of the parameters, data is used (a) from the well documented in the literature p-y curves, and (b) from experiments conducted either in full scale or in the centrifuge. Results are compared to those of well known published codes for inelastic analysis of single piles under lateral load.

Jan 1, 2006

By James Green

It has often been said that the best contracts written are by people who are suspicious of each other. The Spanish philosopher, Ortega y Gasset, said: "Every contract is an Act of Distrust." The arena for dispute settlement outside of the courts is increasing day by day - contracts, especially construction and civil engineering contracts, are written containing arbitration clauses for settling disputes - the very drafting of standard forms of contract, do in some instances by their very construction, create an ambiguity as to intent and provide a breeding ground for dispute. I come from a land far across the sea - the most southern land before the South Pole. Being a young country, 150 years old, we are still progressing - being far removed from the trouble free zones of the world and nuclear free we enjoy a lifestyle second to none.

Jan 1, 1987

By Madhav, V., M. R., Ahmad, Padmavathi, M. S.

Modulus of deformation (Es), also referred to as elastic modulus is dependent on many variables such as type of loading, degree of anisotropy and non-homogeneity of strata, etc. and is one of the most challenging soil parameters to estimate. Modulus of deformation of soil can be obtained from elemental tests in the laboratory, from in-situ tests or on the basis of correlations with other soil parameters. Back analysis of full-scale loading test is the most appropriate method for the estimation of the deformation modulus since the effects of installation and pile-soil interactions are accounted for. Moduli of deformation of the ground are estimated from different pile load tests, viz., compression, pull-out, and lateral load tests and compared. The method of interpretation of pile load test is based on the initial liner portion of the load-displacement curve. Theoretical solutions of Poulos and Davis (1980) and Madhav and Poorooshasb (1988) that relate settlement or displacement with load based linear elasticity theory are used. It has been established that the modulus of deformation of the ground is not unique but depends on the type of test and the type of loading. The differences can be significant.

Sep 1, 2022

By K. Rainer Massarsch

The effects of soil displacement caused by pile driving on adjacent piles and structures are discussed. A method is proposed to estimate the point of force equilibrium which makes it possible to calculate up-lift forces and pile head movements. For the case of pre-coring a method is proposed to estimate the stability of the bore hole, based on cavity expansion theory. Model tests were performed to establish the displacement pattern of the soil during the driving of a pile group. It can be concluded that at the ground surface, already installed piles have little influence on the lateral displacements, but reduce significantly the soil heave. During the driving of a pile group, the soil is displaced according to a complicated pattern, which is strongly influenced by the order in which the piles are driven. In clay the displaced soil volume corresponds to the total volume of driven piles.

Jan 1, 1989

By Rick Ellman, Ian Chaney

"The Hampton Roads area encompassing the Norfolk, Virginia Beach and Newport News metropolitan region experiences some of the worst traffic congestion in Virginia. With continued growth of the ports and increasing demand, the Virginia Department of Transportation (VDOT) initiated the Downtown Tunnel/Midtown Tunnel/MLK Expressway Project, a complex undertaking critical to addressing the Hampton Roads area’s transportation needs. The project is a $2.1 billion Design/Build/Finance/Operate (DBFO) endeavor most notably involving the construction of a new two-lane vehicular tunnel utilizing the Immersed Tube Tunnel (ITT) method. The tunnel will pass under the Elizabeth River parallel to the existing Midtown Tunnel between Norfolk and Portsmouth, Va. It will be the largest design-build project constructed in the history of the Hampton Roads District.The New Midtown Tunnel will extend approximately 6,450 ft (1,966 m) along the north side of the existing tunnel where it ties into the existing Midtown Tunnel approaches in Norfolk and Portsmouth. It is being installed in a pre-excavated trench of which approximately 2,250 ft (686 m) required bracing on the Portsmouth side and approximately 1,000 ft (305 m) required bracing on the Norfolk side. The remaining 3,200 ft (975 m) of trench excavation was open cut dredging with laid back side slopes, optimized to reduce dredging, disposal and backfill quantities while also reducing the risk to the existing tunnel. The braced excavation portions of the tunnel alignment were divided into distinct segments which include: Portsmouth Approach Boat Section, Portsmouth Approach Cut-and-Cover Section, Portsmouth Dredge Section, Norfolk Dredge Section, Norfolk Approach Cut-and- Cover Section and the Norfolk Approach Boat Section. All “approach” excavations were performed in the dry and all “dredge” excavations were performed in the wet. Eleven ITT segments are being fabricated in the Sparrows Point Dry Dock facility in Baltimore, Md., and each 14,000 ton (12,700 tonne) segment is being towed approximately 220 mi (354 km) to the site. The ITT segments will extend under the Elizabeth River, with the deepest crossing 90 ft (27 m) at the Federal Navigation Channel. Once beyond the channel limits the ITT rises at an approximate 4.5% slope. Controlled screeding and element lowering operations will be performed primarily from floating barges."

Jan 1, 2014

By Kent C. Werle

This brief discusses the installation and application of sleeved piles of two different types for two different projects, the W, Seattle to Harbor Island Swing Bridge Project and the Seattle Access Project. A description of these relatively novel piling systems is given, as well as some notes on their installation and application. As implied by the term "sleeved" these are piles which consist of two piles, an inner pile combined with an outer concentric sleeve pile. Background, Swing Bridge The Swing Bridge project is virtually unique in the world in that it is a "lift and turn" swing bridge. It is also a concrete, cast -in-place segmental bridge which is designed to be moveable.

Jan 1, 1990

By Kenneth A. Pidgeon

This paper presents a case history on mitigating vibration problems associated with the installation of steel sheetpiles. The project in-cludes installation of steel sheetpiles for a utility trench within 40 feet (12.2 meters) of a very sensitive manufacturing facility. Numerous production line quality control instruments and manufacturing processes within the manufacturing facility are extremely sensitive to vibrations. To minimize the impact to the owner, we specified that the contractor perform a vibration study using different types of pile hammers. The results and conclusions of the vibration study are presented in this paper.

Jan 1, 1995