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By Robert Alperstein, Nidal AbiSaab, Joe Pastore

"This paper describes the design and construction aspects of the foundation support for a 57-story building currently under construction in lower Manhattan. The site is located near the East River with subsurface conditions consisting of about 40-ft [12.2-m] of unsuitable historic fill and soft plastic clay underlain by about 130-ft [39.6-m] of dense sand resting on bedrock. A mat foundation supported on unsuitable soils improved by jet grouting was selected for the project. Design concepts and selection of the engineering properties of the improved and natural foundation soils are discussed. The results of quality control testing and methods to verify design parameters during construction are presented.INTRODUCTIONNew York City (especially Manhattan) is known for its skyline of high rise structures. The geologic conditions in the New York Metropolitan Area influence the selection of foundations and feasibility of high rise construction as noted by Horvath (2013). These conditions include varying depth and quality of bedrock, multiple glacial events during the Pleistocene Epoch, and the effects of human modifications to the subsurface environment. Clusters of relatively taller buildings are generally located in Lower and Midtown Manhattan where sound crystalline bedrock is at relatively shallow depth beneath the ground surface and shallow foundations rest on the bedrock surface. In recent years the use of more costly high capacity driven piles or drilled caissons and deep basements has enabled the high skyline to spread to other areas."

Jan 1, 2016

By Abid O. Adekunte, David Greentree, David Hilton

"The construction industry is witnessing an upsurge in demand by property developers to have basements incorporated into their residential and commercial development schemes. This is attributable to perceived improvement to aesthetic and commercial values of buildings by underground space, amongst property owners. This trend is compelling more owners of buildings with no basements to explore the possibility of creating underground additional space beneath their existing buildings. The creation of a basement beneath an existing building entails the installation of a reinforced concrete (RC) underpinning system, temporary works, bulk excavation to basement formation level and construction of the basement structure, with associated aesthetic finishes.The L-shaped segmental RC underpins are a common system of choice for such underpinning works. They are multi-functional; providing vertical support to the existing superstructure, providing lateral support to earth and groundwater, supporting temporary and permanent surcharge loads from adjacent structures and services, whilst also forming part of the basement slab. This paper focuses on the first function of the Lshaped RC underpins; capacity under vertical compressive loading from the superstructure. The most common industry approach for the prediction of vertical capacities of L-shaped underpins is the oldfashioned Meyerhof’s (1953, 1963) effective width method, which is based on the traditional bearing capacity theory, whilst accounting for correction factors for eccentricity and foundation depth.The traditional bearing capacity formula is surrounded by a significant degree of uncertainty; estimates are highly user-dependent, as capacity prediction is sensitive to the chosen angle of shearing resistance (?), while there are difficulties in accurately measuring the in-situ ??value of cohesionless soils. In addition, the effective width approach has been shown to be very conservative by many research workers. The segmental RC underpins presented in this paper have been designed with an alternative less conservative method, which involves the use of a recently proposed consistent work-hardening plasticity model calibrated with field-based tests on footings of various aspect ratios and relative embedment in sand. The paper highlights the principles behind underpinning works for urban basement construction, the design of L-shaped RC underpins with the recently proposed plasticity model and the advantages of the method over traditional bearing capacity solutions and pre-existing plasticity models."

Jan 1, 2016

By Franz-Werner Gerressen

"The use of soil improvement to utilize areas, which are not suitable for foundation purpose, has a long tradition. Due to the increasing demand of foundation works in areas of unsuitable soils, the improvement of the existing soils becomes even more important in the future.Various applications and systems for various demands exist around the world. Either it is a “simple” improvement for settlement reduction or a more important aim as liquefaction mitigation. However, each system has its advantages, limits and needs.Furthermore to the soil improvement, using various tools, soil mixing can also be used for applications like cut off and/or retaining wall.The paper will describe some basics of various techniques and different applications of the systems all over the world where the systems provided solutions for different purposes, e.g. simple foundation or liquefaction mitigation.It will describe also the main equipment which will be needed to execute these works under the various conditionsINTRODUCTIONSoil mixing is a methodology where the soil is improved by mixing it with cement, lime or other binders in situ by using a mixing tool. This methodology can be used either as wet mixing or as dry mixing. In the more frequently used wet mixing process, usually a mixture of binder and water, maybe with additives, is injected and mixed with the soil. Depending on the type of soil and binder, by the end of the mixing process, a mortar like mixture is created which hardens during the hydration process. In the dry mixing process, the binder is directly mixed with the soil and reacts directly with the existing soil and water.Mixing tools show several versions, so that they are mixing around either a vertical or horizontal axis, mixing in a trench and maybe are jet assisted. Figure 1 shows a classification done by Bruce 2010. Depending on the technique, improvement depth of up to 80 m can be achieved."

Jan 1, 2017

By Jorge Beim

Helical Piles are increasingly being used to support and rehabilitate structures subjected to compressive axial loads. Traditionally, empirical correlations between installation torque and load capacity of helical screw piles are used as the field quality control. Load tests, however, are always recommended to validate the installation process and design methodology. This paper describes a test program performed on helical piles installed at the National Geotechnical Experimentation Site of the University of Massachusetts - Amherst campus (UMass-Amherst), well known for its deep varved clay deposit. Seven of these piles were submitted to Dynamic Load Tests using the Pile Driving Analyzer® (PDA), and also to Static Load Tests. Good agreements were obtained between the results of the dynamic and static load tests, encouraging the use of the former testing method as a viable alternative to the latter for determining the compressive load capacity of helical piles installed in cohesive soils. The results of the load tests were also compared to the predictions based on torque correlations, resulting in correlation coefficients which were higher than the ones traditionally used.

Jan 1, 2012

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 Meeok Kim, Paul Beljan, Gordon Chen

"Clinton combined sewer overflow storage (CSO) facility project developed by the Department of Water Environment Protection of Onondaga County, New York, is to improve sewer facilities and infrastructure in Syracuse, New York. The below grade facility will provide a storage of untreated stormwater during highflow periods to be treated later, thus reducing CSO discharges to Onondaga Creek.The CSO system consists of three parallel storage tunnels and two end chambers (west and east chambers) as main underground structure. The storage tunnels are about 850 ft. long, 55 ft. wide, 24 ft tall and located 20 ft deep below grade. The chambers, include above access and operation structure, are about 40 to 55 ft. deep and approximately 60 to 100 ft. wide.Kiewit Infrastructure and Weidlinger Associates Inc. developed an alternative approach for the tunnels to meet the facility completion schedule, strict design guide lines and quality control as an environmental and water tight concrete structure for the project. The original design anticipated use of a TBM machine to bore three parallel tunnels between two previously constructed chambers.The alternative design used a three barrel culvert cast-in-place structure in a cut and cover excavation supported by a soil bentonite wall. The SOE along the jet grouted bottom seal provided a ground water cut off as well.The SOE system is specially designed to enhance the quality of culvert CIP structure construction by providing enough space for a full height construction. Also it further reduces the construction time by having the less squarefootage of jet grout installation. The design of tunnel systems is accomplished effectively through the utilization of soil structure interaction using a finite element methodIntroductionTo avoid construction of an additional treatment plant to handle increases in combined sewage flows, the Department of Water Environment Protection of Onondaga opted to construct the Clinton combined sewer overflow storage (CSO) facility.The Clinton CSO facility provides an environmental friendly mitigation method for combined sewer overflows on Onondaga lake which is located in northwest of Syracuse."

Jan 1, 2015

By Max Gwynn, Tony Suckling

"The new Wembley Stadium is the most spectacular soccer stadium in the world, built to the highest specifications, using the latest technology and offering visitors an unrivalled match-day experience. Wembley Stadium is the home of English soccer, dating back to 1918 when the British Government began planning a British Empire Exhibition with a stadium as its centrepiece. The Empire Stadium, as it was originally known, was completed in 1924 in just 300 days and cost £750,000 ($1.4m). It was finally closed in 2000.The new Wembley Stadium, which opened in 2006, features fully covered seats for 90,000 fans and a striking arch that sits above the northern half of the stadium. With a span of 315 m (1040 ft), the 133-m (440-ft) tall arch is the longest single-span roof structure in the world. It supports the entire weight of the northern roof and 60% of the weight of the southern retractable roof. This means there is no need for columns within the stadium and ensures unobstructed views.Multiplex Constructions (UK) Ltd. employed Stent Foundations Limited to construct the £10m ($19m) foundations package for the new stadium. The scope of works for the foundation package included the design and construction of all foundations, including all main works piling, temporary works piles for the arch and roof, and tower crane piles. The scope also included trial piling and pile testing, setting out and removal of spoil.Piles were constructed by using bored cast-in-place techniques with both hydraulic and traditional crane-mounted rigs. Stent also installed sheet-piled walls at three locations to the site’s northern boundary. In addition to the main contract works, Stent constructed a £2m ($3.8m) contiguous bored-pile retaining wall within the demolition and earthworks package (Figure 1). This work was carried out as a subcontractor to Griffith McGee."

Jan 1, 2008

By Karl A. Higgins

In 1976, Prof. G. G. Meyerhof published a famous article in the Journal of Geotechnical Engineering titled ?Bearing Capacity and Settlement of Pile Foundations?. This article presents the authors opinions on calculating pile capacities in clays and sands, group capacities and pile settlement. A portion of the article presents correlations of shaft friction and end bearing to the Standard Penetration Test (SPT) N-value. Subsurface exploration via the Standard Penetration Test is the most widely used exploration tool in the United States, so correlations of pile capacity to N-value are significant to the practice of geotechnical engineering. Meyerhof?s SPT-N correlations are relatively simple calculations compared to other pile capacity computation methods presented in the article or found in other text books (such as the a-method, b-method, Nordlund, Vesic, Meyerhof?s semi-empirical, others) and therefore are popular amongst practicing geotechnical engineers. At the time these correlations were published by Prof. Meyerhof, utilization of dynamic testing with the Pile Driving Analyzer (PDA) was not widespread in geotechnical engineering practice. Prof. Meyerhof?s correlations appear to be based upon conventional static pile load testing of instrumented piles. Dynamic pile measurements to estimate a pile?s static capacity provides certain advantages over conventional static load testing, namely the determination of unit shaft friction values at discrete intervals along the pile, and the unit end bearing support value. The author has compiled a database of driven, displacement piles tested with dynamic methods (ref. ASTM D4945, Test Method for High-Strain Dynamic Testing of Piles). The data was collected between 2002-2010 and is comprised of displacement piles driven into coastal plain sediments in the mid-Atlantic states of Virginia, Maryland and the District of Columbia. In layered soils, dynamic testing in particularly helpful as it reveals the differences in unit shaft friction for varying soil types. One hundred ninety (190) piles are included in the database, with a corresponding 1,373 discrete shaft friction and 190 end (toe) bearing measurements. The pile type typically consisted of 12 and 14 inch square, prestressed, precast concrete piles; however, a significant number of piles were steel HP 12 or 14 inch sections. The database was sorted based upon soil type, and then correlations of shaft friction and end bearing were derived in the same or similar manner as Meyerhof?s original 1976 publication. The new correlations are compared to Meyerhof?s original values.

Jan 1, 2011

By Masaki Kitazume, Yoshiaki Kikuchi

"Abstract Pile foundation is one of fundamental techniques to improve the bearing capacity and settlement characteristics of superstructures. Wide varieties of piles having various shape, size and material were developed and have been applied to a lot of construction projects throughout the world. The deep mixing method, an in-situ admixture stabilization method, was developed in 1970s in Japan and the European countries, and has been frequently applied to many construction projects for various improvement purposes such as increasing bearing capacity and horizontal resistance, reducing ground settlement, preventing liquefaction and so on. The design methods, execution procedure and quality control and assurance (QC/QA) of the method are standardized or specified in many countries. These standards, specification and/or technical manual have been a remarkable contribution to spread the techniques throughout the world. The QC/QA is one of the major concerns for clients and engineers who have poor or no experience of the technologies. In order to assure the high quality of deep mixing work in the global market, it is necessary to establish the concept of QC/QA and correlate the output of different procedures. Upon the request by the organizing committee of the DFI-EFFC International Conference on Piling & Deep Foundations, the authors conducted survey of the specifications and standards on the piling and deep mixing technologies in Asian countries. In this manuscript, the results of survey are briefly introduced by comparing these specifications and standards.IntroductionThe pile foundation is one of fundamental techniques to improve the bearing capacity and settlement characteristics of superstructures. Wide varieties of piles having various shape, size and material were developed and have been applied to a lot of construction projects throughout the world. The design method, execution procedure and quality control and assurance of pile foundations are standardized in many countries based on the accumulate research results, laboratory and field experiences. In Japan, steel pipe piles are mainly constructed by hammer driven in port construction. On the other hand, precast pre-stressed concrete piles or cast-in-place piles are mainly used in on land construction. When precast pre-stressed concrete piles are constructed, piles are usually set by inner excavation method because of preventing noise and vibration problems. More than 50 years ago, noise and vibration problems had not been serious problem in Japan, but around 50 years ago, they became serious and now less noise and vibration construction methods are used for pile construction on land in Japan. In Asian countries, though piles used for construction have a lot of variety, precast pre-stressed piles are commonly used. In this report, execution controls of construction methods of steel pipe piles and precast concrete piles are mainly considered."

Jan 1, 2014

By Javankhoshdel Yacoub

Piles are often used to reinforce slopes as they increase the available restoring force when calculating the factor of safety against sliding. In this paper, a 3D model of a slope containing multiple modes of failure is reinforced using pile elements. The results of the 3D Limit Equilibrium analysis containing piles are obtained using a newly introduced coupled approach which combines the results of finite element analysis (to obtain the displacement of soil along the pile) with the traditional limit equilibrium iterative formulation. The multiple modes of failure are obtained using the novel Multi-Modal Optimization (MMO) metaheuristic method which adapts the Particle Swarm Optimization (PSO) method to search for multiple local minima in a single slope model.

Oct 1, 2022

By Michael J. Marasa

"Geotechnical engineering and construction primarily relies on the subsurface characteristics of the particular site; however, obtaining both accurate and precise information on those features is challenging due to the numerous factors involved in testing procedures used to analyze varying site geology. This includes a detailed and thorough geotechnical investigation to understand the site conditions, allowing the implementation of the most practical and economical solution.This paper presents a case history of the installation of wick drains and construction of aggregate piers on the site of a large facility to be constructed in Memphis, Tennessee. Throughout intensive subsurface investigations, highly variable soils were encountered, requiring settlement control and increased bearing capacity. This paper will discuss the design and installation of the systems constructed, and procedures and execution of the work to ensure design specifications were achieved.BackgroundA 1.4 million square foot expansion directly adjacent to an existing 1.1 million square foot distribution facility in Memphis, Tennessee was planned to serve as a centralized facility for increased production. The first phase of construction included an 858,000 square foot warehouse and parking lot for approximately 400 trucks to the north of the existing structure. The anticipated column load for the warehouse was 125 kips; slab design bearing pressures ranged from 200 to 500 pounds per square foot (psf) and elevations ranged from EL. 264 to 282. Parking lot elevations ranged from EL. 264 to 290, requiring a design life of 10 years with an estimated 100 in- and out-bound trucks daily and maximum weight of 80 kips per truck. The second phase of construction took place east of the existing structure, and included a 794,000 square foot multi-level warehouse, a 100,000 square foot office, and additional employee parking. The anticipated column load for the second warehouse was 225 kips and slab design bearing pressures ranged from 200 to 500 psf. Elevations ranged from EL. 267 to 282. Anticipated column loads from the office were 25 125 kips, with slab design bearing pressures ranging from 100 to 200 psf. Due to the varying elevations within each planned footprint, up to 18 feet of new fill was required to match the existing structure’s finished floor elevation (FFE) at EL. 282."

Jan 1, 2017

By J. Osterberg

A new device has been developed for load testing driven piles and drilled shafts which consists of an hydraulic jack or bellows which has a telltale rod fastended to the bottom. The rod extends upward to the surface through a pressure pipe. When pressure is applied, the jack or bellows expands, applying an equal upward and downward load at the bottom. The downward movement at the bottom is indicated by the rod and the upward movement is indicated by the movement at the top. Thus, upward and downward load-deflection curves can be drawn. As load increases, failure will occur either in end bearing or friction. Results of field installations are described. Total loads of up to 1,100 tons metric have been used. The method obviates the need for the reaction load required for the conventional pile loading test and separates friction and end bearing. It is especially advantageous for use over water, in crowded spaces and for inclined piles.

Jan 1, 1989

By Martin van Staveren

In today's rapid changing construction world, the business pressures on piling and deep foundations reach sky-high levels. Ever increasing complexity of construction projects do severely contribute to these business pressures. Projects are often constructed in densely populated areas and located close to vulnerable buildings and infrastructure. The inherent uncertainty of ground conditions plays a dominating role in these foundation projects. Effective risk management is a key success factor for profitable and sustainable operations of piling and deep foundations. It starts with a fundamental requirement to be aware of risks. Next the different risk perspectives of all stakeholders in any foundation project have to be acknowledged. A simple and structured risk management approach is introduced, to demonstrate that effective risk management is not necessarily that complicated. A major element is the contractual allocation of risks, as a result from differing ground conditions. It is based on the so-called Geotechnical Baseline Report (GBR). The main objective of the GBR is to provide a clear contractual arrangement for the allocation of risks, arising from differing site conditions. The benefits of explicit risk management in general and contractual risk allocation in particular are illustrated with an example and experiences. The presented structured risk management approach, including contractual risk allocation, is still rather new. It proves to be promising for cost-effective risk control of piling and deep foundation projects, anywhere in the world.

Jan 1, 2006

By Konstantin G. Ashkinadze

The paper considers performance of piles supporting transient pipe anchors in heavy industrial pipelines. Events such as pump trips or opening and closing of large valves produce short-term dynamic pulses in the pipeline with variable spectral characteristics. Their magnitude is large enough to cause major damage to the pipeline and its anchors, which face horizontal impact loads amounting to hundreds of kN. Design of pile foundations supporting these anchors is often governed by limitation of deflection of the support to prevent overstressing pipeline connections and equipment nozzles. The maximum deflection does not always correspond to the largest load because the stiffness of the soil surrounding the piles heavily depends on the rate of loading. Faster actions encounter stiffer soil response while loads of smaller magnitude applied slowly may be more critical for the deflection time history of the anchor. A typical transient action has both high- and low-frequency harmonics, which makes the response complex. Using load rate-dependent p-y curves published in literature, the paper develops methods of analysis of pile foundations for transient anchors. Pile displacement amplitude – input frequency – natural frequency correlations and time histories of pile response are constructed for typical profiles of transient actions, considering nonlinear soil response to large horizontal loads.

Jan 1, 2016

By Allan Sylvester

Construction of the Shot Tower Metro Station in Baltimore, Maryland was performed in two phases. In the first phase, a contractor was retained to excavate the station in order to construct twin tunnels from the Shot Tower Station to the John Hopkins Station. The retention system for this 70' deep excavation consisted of a Soldier Pile in Tremie Concrete (SPTC) wall supported by cross-lot bracing. In phase two, The Clark Construction Group, Inc. was retained to construct the station interior structure, two entrances, two station ancillary shaft structures and the track work for the station and tunnel. The excavation for the construction of the two entrances adjacent to the 70' deep station SPTC wall had to proceed prior to completion of the station structure due to the tight construction schedule. A system of overlapping secant piles was specified as a vertical support of excavation element for the West Entrance. The secant piles would have provided a watertight, rigid support to resist the load from the SPTC wall constructed in phase one. A watertight system was required in order to minimize the settlement of adjacent buildings supported on wood piles. Clark Construction was concerned with the constructability, cost and performance of the specified secant piles and looked for other innovative methods of providing a watertight and rigid system. Substitution of a reinforced slurry wall in lieu of the secant piles was cost prohibitive due to the additional cost of concrete placed under tremie. Clark, being familiar with cement-bentonite cut-off walls and slurry wall construction procedures, proposed the construction of a PSHG wall, in lieu of the secant piles. The PSHG wall construction consisted of trenching 30" wide by 20' long by 60' deep panels under a self-hardening slurry. Once the excavation for a panel was completed, a 60' deep prefabricated soldier beam and lagging panel was placed in the slurry. The slurry design mix then self-hardened within the cure time, allowing excavation for the structure to proceed This paper will discuss the design, details and construction methods used on the PSHG wall and will compare the advantages of the PSHG system to conventional support systems.

Jan 1, 1997

By Cristhian C. Mendoza, Renato da Cunha, Bernardo Caicedo, Max Barbosa

"Abstract This paper shows that a raft alone is not sufficiently appropriate to address the uncertainty of underlying soil variability; therefore, a piled raft system is a better option for mitigating such uncertainty. To study the variability of soil, the behavior of the Piled-Raft Foundation was analyzed with a type of self-drilling micropiles: the ""Alluvial Anker"" (common name for this pile type in Brasilia city). These micropiles have been used in the city and have the advantage that the drill pipe also serves as reinforcement. The studied parameters belong to an elastoplastic constitutive model for strain-stress analysis of soil; variability of these parameters can be intrinsic and/or epistemic. Simulations were performed for a hypothetical Piled-Raft Foundation subjected to vertical loading using the random finite element method. The average parameters of the constitutive model were obtained through laboratory tests. The simulations of the load test were compared with results of a real scale experimental test conducted exclusively for this work in the field. It is analyzed the relative importance of the variability of some geomechanical parameters and their variation with depth is considered. In addition, it is discussed a comparison between the uncertainty of the geomechanical parameters and the uncertainty of the results of the vertical loading test. Finally, this paper shows that a decrease of the safety factor may occur when taking into account the variability of the parameters.IntroductionBrasilia is located in a highly weathered residual tropical soil (lateritic & latossol on pedogenetic concepts). This soil presents high content of alumina and iron due to the lixiviation process of the upper layers. As a consequence, the cemented structure is highly unstable and it can generate strong changes of volume (i.e. collapse) due to changes in both moisture and state of stresses. Therefore, a greater understanding of the construction of Piled-Raft Foundation systems on this particular soil conditions is needed – especially because it covers more than 80% of the surface area of the Brazilian Federal District.Thereafter, this work investigates the influence of the variability of the soil parameters over the uncertainty of the Piled-Raft Foundation design. The studied parameters belong to an elastoplastic constitutive model for strain-stress analysis of soils. The simulations were performed for two hypothetical Piled-Raft Foundations subjected to vertical loading by using the stochastic finite element method. The results were compared to real load tests in Piled-Rafts with “Alluvial Anker” pile types."

Jan 1, 2014

By Klaus Pöllath

The Netherlands RandstadRail project makes use of a large range of sophisticated geotechnical techniques to allow a shield driven tunnel to approach the central station of Rotterdam. This paper describes the construction of three deep excavation pits constructed with 1.2 m and 1.5 m thick diaphragm walls. Besides the presentation of the actual diaphragm wall activities special consideration is given to the break-in and break-out situations of the TBM into the deep excavations pits using sealing blocks and partly glass fibre reinforcement in the diaphragm walls.

Jan 1, 2006

By Dan Brown

This paper presents a case study of a cyclic lateral pile load testing program performed on two 18-in square prestressed concrete piles (PSC) in Savannah, Georgia. The load test program was developed to simulate the lateral behavior of a single pile under seismic loading conditions for the design and construction of a large LNG storage tank. The lateral load tests included cyclic loading to measure possible degradation in soil response followed by static loading to large displacements (around 6 inches at the loading point). The lateral load was applied through a reciprocating jack positioned to push and pull the piles against each other. The test piles were instrumented with multiple displacement transducers, downhole inclinometer, and strain gauges. This paper provides an interpretation of the test results regarding the pile performance and soil response to monotonic and cyclic lateral loading. A backfitted computational model of the soil resistance was developed to match the test results using the LPILE computer program. The load-deflection and deflection/moment versus depth comparisons suggest that this model appears to capture the behavior relatively well within the general range of suitability for design purposes. New design curves were developed based on the soil parameters derived from the lateral load test results.

Jan 1, 2003

By R. L. Xu

In this paper, the author would like to point out with figures that the building industry is one of the key industrial sectors of the national economy in China. And in the coming 15 years, the output of building construction will not in the least decrease, but increase. The requirements for building standards, quality, functions as well as physical environment will also be higher along with the incessant development of the national economy and the gradual raising of people's living standard. China is a country with a vast territory and a great, variety of physical characteristics. The topographic and engineering geotechnical conditions are complex and varies considerably from place to place. Although, in recent years, encouraging progress has been made in building construction, there still exist many problems unsolved or even not explored at all, which we have to tackle in the future design and construction of foundations. Also reviewed in this paper are the achievements attained in the past thirty odd years and the challenge we will face in the foundation engineering field in China.

Jan 1, 2010

By Wen Songlin

This paper presents an experimental program to investigate the behavior of a pile with wings under horizontal loads in sand at laboratory. The work focused on evaluating the lateral resistance behavior and the geometric effect of wing board on the horizontal resistance. Based on the measured data and observed phenomenon, the following behaviors have been observed: 1) A pile with wings is not only a powerful means to improve the horizontal bearing capacity of a pile foundation but also economy and feasibility; 2) The horizontal bearing capacity of a pile with wings increases with increasing of it?s wing board?s area; 3) The pile lateral capacity is also influenced by the wing board?s geometric shape. Under a certain soil and pile condition, there is a critical embedment depth of the wing board, which will yield the maximum horizontal bearing capacity. It was further observed that when the displacement of the pile head increases, part of the horizontal bearing capacity of the pile is developed by the so-called shaft?s anti-pulling capacity.

Jan 1, 2007