Search Documents

By Kyle Murphy, John S. McCartney

This paper focuses on the seasonal thermo-mechanical response of two energy foundations installed at the new Denver Housing Authority Senior Living Facility in Denver, Colorado. The two drilled shaft foundations, which have diameters of 36 inches and depths of 45 ft and are end bearing in the Denver shale formation, include a closedloop series of polyethylene tubes through which fluid is circulated to exchange heat with the surrounding ground. The tubes within the foundations are coupled together with the conventional ground source heat pump system for the building and were installed to evaluate the heat exchange response of the foundations as well as any thermomechanical soil-structure interaction effects. A series of vibrating wire strain gages and thermistors were installed at different depths in the foundation to record the thermomechanical strain and temperature at different depths. Also, pipe-plug thermocouples are used to measure the inlet and outlet temperature of the heat exchanger fluid entering each of the foundations, which is necessary to evaluate the total heat exchange for the foundations and the efficiency of the heat pump. This paper will describe the energy foundation construction processes, the strain distribution and ambient temperature profiles during building construction and the seasonal strain and temperature distributions during heating and cooling of the building. The data indicates that typical heat exchange associated with heating and cooling operations leads to strains which are within acceptable limits, and that the foundations can provide a clear option for absorbing the base heating and cooling load for the building.

Jan 1, 2017

By John S. McCartney

This paper focuses on the seasonal thermo-mechanical response of two energy foundations installed at the new Denver Housing Authority Senior Living Facility in Denver, Colorado. The two drilled shaft foundations, which have diameters of 36 inches and depths of 45 ft and are end bearing in the Denver shale formation, include a closed-loop series of polyethylene tubes through which fluid is circulated to exchange heat with the surrounding ground. The tubes within the foundations are coupled together with the conventional ground source heat pump system for the building and were installed to evaluate the heat exchange response of the foundations as well as any thermo-mechanical soil-structure interaction effects. A series of vibrating wire strain gages and thermistors were installed at different depths in the foundation to record the thermo-mechanical strain and temperature at different depths. Also, pipe-plug thermocouples are used to measure the inlet and outlet temperature of the heat exchanger fluid entering each of the foundations, which is necessary to evaluate the total heat exchange for the foundations and the efficiency of the heat pump. This paper will describe the energy foundation construction processes, the strain distribution and ambient temperature profiles during building construction and the seasonal strain and temperature distributions during heating and cooling of the building. The data indicates that typical heat exchange associated with heating and cooling operations leads to strains which are within acceptable limits, and that the foundations can provide a clear option for absorbing the base heating and cooling load for the building.

By Paul Suver

"The closed loop standing column well (CLSCW) system uses a closed circuit of water to develop the same thermal heat exchange characteristics that are achieved from traditional open circuit standing column well that uses the ground water directly. Pipe pile and pipe anchor foundations can be used as CLSCW components for ground source heat exchange. New data gathering and analysis techniques and equipment installed in the heat pumps allow any mechanical engineer to design the system without specialty engineering equipment and certifications.CLSCW Description:Closed end steel pipe of varying outer diameter (O.D.) is installed by various technologies at varying depths depending on subsurface geology. The wells are arranged as stand alone wells or in groups joined in parallel or in series or in a combination of both. These pipes may also serve a dual function as foundation supports, deep foundation pile, anchors or earth retention components. These wells are then internally coated to minimize corrosion. The wells are then plumbed and capped to create a vessel equipped with a supply and return water line.The stand alone well or group of wells is then used as a ground heat exchanger for a ground source heat pumps located in or around the building.The ground source heat pumps provide heating and cooling to the building either with a traditional ducted distribution system or with radiant heating and cooling. These systems can reach efficiencies three times greater than traditional gas fired heat sources and five times greater than traditional air conditioning sources."

Jan 1, 2017

By Vivian M. Troughton, Clifford J. Wren, Tony P. Suckling

"Secant pile walls are used for the construction of deep basement walls and earth retaining structures. Risk associated with secant pile walls is commonly perceived as being the safety of site personnel and the public during piling operations, or safety used in design. It is recognized that both of these are of paramount importance, but additional risks associated with the construction methods must also be considered to complete the risk management profile for any project. For the particular case of secant pile walls, if Clients take a ""back seat"" they may be unaware of the total risk package they are procuring. The authors argue that the piling contractor should be involved at the earliest stage giving input into the overall risk management process. Such early involvement within the professional team will maximise cost benefits to the Client and minimise the delays and cost increases sometimes associated with these works. A consistent methodology for identifying and then managing all the risks associated with secant pile walls is proposed. An example is used to demonstrate how this methodology should be employed. INTRODUCTIONThis paper discusses the value of a complete and integrated risk management process for structures with basements formed using a secant pile wall.The risk associated with any secant pile wall can be consicfered as comprising four components;1. Safety of people on site2. Safety of design or design methodology3. Construction risks4. Commercial risksAny risk management system needs to fully consider and integrate each of these four components to maximise the likelihood of a successful outcome for the basement.This paper concentrates on the construction risks for secant pile walls, as these are not often understood by the Client (in this paper the term ""Client"" also includes the main contractor, principal contractor, Engineer, Planning Supervisor, quantity surveyor and cost consultant)."

Jan 1, 2005

By Naoyuki Hanawa, Takeo Asanuma, Tatsuo Nagatsu, Sachihiko Tokunaga, Daisuke Nakagawa, Yoshiyuki Morikawa, Kazuhiko Ueno

"In the cement deep mixing (CDM) method, one approach to joint construction is creating a surface-contact joint. In this study, an unconsolidated-undrained triaxial compression test was performed on cement-treated soil specimens with joints artificially created by successive pouring. The effects of the presence or absence of such successive pouring joints on the strength of the specimens were then examined. The results showed that the compressive strength of the specimen decreased by approximately 0%–30% with a successive pouring joint.INTRODUCTIONIn the block type and wall type improvement patterns of the CDM(Cement Deep Mixing Method) application, an integrated body of soil-cement columns is constructed by partially overlapping individual treated soil columns. The overlapping operation should be implemented before the hardening of soils by cement progresses and thus, this operation is routinely performed in construction sites usually within 24 hours or within 48 hours at a maximum. However, when the operation is forced to be interrupted on account of a typhoon or any other adverse weather conditions, it is impossible to carry out the overlapping operation within the above time limitations. In such a case, it is necessary to improve the integrity between the treated soil columns solidified first and the treated soil columns to be constructed later.One of the methods that can be adopted is to prior agitate the target area by mixing blades “without cement”, integrating the preceding treated soil columns and the subsequently treated soil columns at construction joints. This method has been adopted so far in numerous sites because no additional materials or equipment are necessary. However, its effectiveness has scarcely been evaluated quantitatively in conventional studies.In the circumstances, the authors investigated in the present research the effect of the presence or absence of construction joints on the specimen strength by performing unconsolidated-undrained triaxial compression tests using specimens of cement treated soil artificially provided with surface-abutting construction joints.Therefore, this study examined the effects of the presence or absence of artificially created successive pouring joints on the strength of cement-treated soil specimens through an unconsolidated-undrained triaxial compression test."

Jan 1, 2015

By James C. Scott

Compression and tension load testing were performed on bored concrete piles installed to depths of 18 to 34 meters below excavation levels for a large mixed-use development in Kuala Lumpur, Malaysia. The 900 mm diameter piles were installed in weathered graphitic schist bedrock. Load testing confirmed the side shear and end bearing capacities of the piles. The work formed part of the investigations for the 56,000 m2 site which includes a 79-story office tower, hotel tower, apartment tower, retail complex, and plaza area underlain by 4 to 6 basement levels. The paper provides the results of the site investigations, pile-load testing procedures, pile-load settlement behavior, and shaft load distribution.

Jan 1, 2007

By Mark Spence, Tom Lardner, Matthew Janes

"IntroductionThe design-build method streamlines project delivery through a single contract between the Contract manager and the design-build team. The design-build method places emphasis on collaborative project management between design and construction disciplines to minimize project schedule, reduce costs, encourage balance risk amongst the design-build team. Since 1985, the percentage of nonresidential design and construction projects has increased from 5% to 45%.1A project carried out in Edmonton, Alberta, Canada will be used as an example to illustrate the challenges of the design-build project delivery method and the merits of establishing a GBR. The project involved a complex slope stabilization as part of an extensive freeway widening. At the project location the roadway was being widened within the base of a historic stream valley into a steep slope with a history of a previous slope failure. The slope was to be steepened through the installation of a series of 14 interlocking arc structures constructed half way up the slope. Access and schedule proved critical to the successful completion of the project.Geotechnique and Site HistoryThe geotechnical investigation undertaken for the site included six boreholes drilled at the crest of the slope to depths ranging from 14.5 m to 30.2 m. Laboratory testing of the soil samples included direct shear tests, Atterberg limits and grain size analysis. The geotechnical report also referenced a previous geotechnical investigation that was carried out in response to a failure of the slope in 1971."

Jan 1, 2015

By Dileej M. Dewaikar, Poonam A. Patil

"In this paper, the ultimate lateral resistance of a long, flexible, unrestrained vertical pile in a cohesive soil is computed under static loading condition using py curves. A simple and improved method for the construction of hyperbolic p-y curves for a cohesive soil is proposed for static loading conditions. An iterative analysis is employed with secant modulus approach, using a matrix method known as moment area method developed by Sawant and Dewaikar. The loadground line displacement relationship is obtained for different load eccentricities using p-y curves developed by Matlock, Georgiadis et al. and the proposed hyperbolic p-y curves for different eccentricity ratios. These values are compared with the values computed from model test performed by Rao et al. and with the limit equilibrium solution given by Broms. The comparison shows that, the results obtained using hyperbolic p-y curves shows a better agreement with the model test data with the maximum difference within 15% using other methods; whereas Broms' limit equilibrium solution shows some agreement with the results based on Matlock's p-y curves.INTRODUCTIONPile foundations are used for jacket type offshore structures, which are subjected to large magnitudes of lateral loads due to lake or ocean waves, winds and ice forces. The failure of a pile-soil system is catastrophic and excessive deflection of the pile creates operational difficulties. In the view of this, bending moment in the pile is required to be predicted in a rationar manner. The p-y concept developed by Reese and Matlock (1956) is popularly being used to estimate the pile top deflection and bending moments.The ultimate lateral load which causes collapse of a pile-soil system is generally estimated using Broms' (1964) method, which is based on limit equilibrium considerations. The p-y curves are basically nonlinear in nature and include ultimate pressure at the depth where they are generated. Therefore, if the lateral deflection of pile top against different magnitudes of lateral load is obtained, it should be possible to obtain the ultimate lateral load from this load-deflection relationship."

Jan 1, 2005

By Michael Arnold, Robert Bachus, Michael Bracher, Jamey Rosen, Robert Roff

"For a high hazard USACE facility, the Center Hill Dam in Tennessee, several disparate streams of data were compiled into a single geospatial and relational enterprise data management system to store, analyze, visualize and distribute the data collected during installation of a deep cutoff wall. These data streams included historical drawings and pre-construction plans and grouting records; geological data from boreholes; attributes of barrier wall elements; element verticality data analyzed from multiple measurement methods; and concrete field and laboratory analytical data. A previously developed data management system developed by the authors, WallTracker, was extensively modified to also include manually collected and real-time measurements from several types of dam monitoring instruments. The system now uses enterprise database technologies with Geographical Information Systems capabilities to manage and relate these data streams into a common platform and allows access to the raw and interpreted data via web and desktop-based interactive tools, including interactive map and cross-sectional viewers and other graphical and tabular reporting tools. One of the primary benefits of this system is the neartransparent interaction that is possible with the Nashville District of USACE on the project. These techniques can now be effectively incorporated into systems that address the unique construction and data management tracking requirements for dams, dikes, and levees.IntroductionThe Center Hill Dam rehabilitation, as with other deep foundation installations, requires the contractor to collect a substantial amount of information over the course of the project, both for internal quality control of construction progress and methods, and for demonstrating compliance with owner specifications. This paper discusses techniques used at Center Hill Dam for consolidating, visualizing and analyzing construction and instrumentation data using relational database and Geographic Information Systems (GIS) technology, collectively referred to as an Information Management System (IMS).The remainder of this paper presents the needs and objectives of the IMS, the components and data flows involved, the capabilities and user interfaces of the systems, and the benefits for the end users."

Jan 1, 2017

By Dario Libano, Armando Caputo, Francisco Caputo

"UHE Peixe Angical is a 452 MW hydroelectric power plant located on the Tocantins River in Tocantins, Brazil. In 1999, geologists began feasibility studies to estimate the river’s hydroelectric potential, and the decision was made to proceed with the construction of a power plant. In 2002, after extensive investigation, the studies indicated geological homogeneity at the site for the dam, except for an anomaly detected on the left margin, and construction began on the $1.2 billion project.As the work began, the complex ground conditions presented several serious difficulties. The solution was unlike any undertaken before in Brazil— a 100-m-long secant cutoff wall, with 76 1.8-m-diameter piles of up to 78 m deep. All were placed in a six-month period.In the preparation for the detailed construction plans, further studies in the area of the anomaly better defined the geology so that a treatment program could be developed. The feasibility study had detected silicified rock with high permeability in one area, and an injection curtain was designed with five injection lines. In the other area with an anomaly, further investigation revealed a permeable marble formation that was 50 m thick. Here, a specific injection program with three injection lines was developed.The injections started in February 2005 in the marble formation area. By July of that year, only the primary and secondary holes were drilled from the three lines, resulting in a space between injections of 1.50 m. By the end of July, the drilling was halted. The contractor had identified a thick area of heterogeneous material below the transition zone that was characterized by a mixture of soil, fractured rock and hard fractured rock. The anomalies were detected while drilling, and both the general contractor and the designer concluded that the phenomenon of “piping” was taking place.Constructing a positive cutoff wall became a priority."

Jan 1, 2009

By Douglas Heenan

The fracture orientations were inferred based on theory and previous experience. The fracture pattern was not monitored during the project. Grout volume was recorded at each sleeve port and real time movement monitoring of the building foundation was performed.

Feb 10, 2003

By Alison Savage, Michael Terry

"For decades, the International Market Place (IMP) has been an icon in the heart of Waikiki in Honolulu, Hawaii. It was famous for Duke Kahanamoku’s restaurant where people flocked to hear Don Ho sing in the ’60s and ’70s. Later, it was a bustling, open-air hub of small vendors who peddled everything from Hawaiian souvenirs and jewelry to food court meals and farmer’s market produce. Small buildings and shacks that housed the businesses were located on a curved tract of land — just one block off the beach — that stretches from Kalakaua Avenue to Kuhio Avenue. The entrance to the complex is dominated by a huge, old (circa 1850) Banyan tree. This tract is owned by the Queen Emma Land Company. Queen Emma was a Hawaiian Queen from the 1800s. Revenue from the land has supported the Queen’s Medical Center in Honolulu for decades.The reimagined IMP is owned by Taubman Centers, of Bloomfield Hills, Mich., and CoastWood Capital Group of San Francisco, Calif. The IMP will offer a distinctive collection of upscale fashion and lifestyle retailers, including Hawaii’s only Saks Fifth Avenue store, as well as ten sit-down restaurants, including concepts by award-winning chefs Michael Mina and Roy Yamaguchi. The mall features two large open-air courts, the first of which has the huge Banyan tree as its entryway centerpiece. The second open-air court, called Queen’s Court, includes a stage and mature monkeypod trees and a few palm trees. Foundation SelectionAfter a geotechnical exploration that was directed by SME, Plymouth, Mich., and performed by Geolabs, Honolulu, it was discovered that the historical site had hidden and challenging foundation conditions. The subsurface conditions included a very deep but now in-filled ancient river valley containing more than 180 ft (54.9 m) of lagoonal deposits consisting of normally consolidated plastic clayey silts and silty clays with blow counts mainly varying in N-value from 1 to 6. The silt was underlain by several soft coralline layers, some overconsolidated clays and various basalt layers. The static groundwater level on the site was at a depth of about 5 ft (1.5 m), closely matching sea level.Although driven piles had previously been used as the preferred deep foundation support for adjacent structures, this area of town is now fully developed and local noise ordinances preclude their use. Augercast piles were initially considered, but when the general contractor dck/FWF, Pittsburgh, Pa., asked for bids for the augercast piles, several foundation contractors offered alternate systems. The practical installation depth of augercast piles was limited and due to the depth of the in-filled alluvial valley, this system could likely have left soft silt below the tips of the piles over much of the site."

Jan 1, 2016

By Bidjan Ghahreman

A total of 120 micropiles were constructed for foundations of a new selective catalytic reduction (SCR) unit in a coal-fired power plant east of Kansas City, Missouri. Construction was performed under restricted overhead conditions because of the existing facilities. The subsurface profile included about 70 feet of overburden composed of granular fill, stiff to very stiff cohesive material, medium dense sand, and very dense gravel. The bedrock was composed of alternating layers of shale and claystone (weak rock) and limestone (strong rock). It was decided that the bond zone would be entirely in the bedrock. The design rock profile along the bond zone was composed of 10 feet of shale and claystone underlain by 10 feet of limestone, which in turn was underlain by shale and claystone. To achieve the design compression and uplift capacities of 100 tons and 60 tons, respectively, a length of 23 feet was determined for the bond zone. Compression and uplift load tests were performed to verify the design. IBC-2000 elastic line, Decourt (1999) extrapolation, and Chin-Kondner extrapolation were used to interpret the load test results. The interpretation of load test data indicated that both compression and uplift capacities far exceeded the respective design loads. Spring constants of 397 tons per inch (T/in.) (in compression) and 290 T/in. (in uplift) were estimated from load tests at respective design loads. During the compression load test, no sign of creep was observed after the applied load was maintained at the design load (100 tons) for two hours.

Jan 1, 2009

This paper summarizes seven years of Italian ex­perience with the use of large calibration chambers for the calibration, under closely controlled stress and strain conditions, of some in situ testing devices which are used in sand deposits. At the present time two calibration chambers are operating in Italy, one at E.N.E.L.-C.R.I.S. (Milan) (*) and the other at I.S.M.E.S. (Berga­mo) (**). Both chambers can accomodate cylindrical samples 1.2 m in diameter and 1.5 m in height. A detailed description of these chambers can be found in Bellotti, et. al (1982).

Jan 1, 1987

By Ping Yang, Tian-bin Li, Min-hui Wu

"The process of filtrate loss of low solid-phase drilling fluid at different content of polyanionic cellulose is investigated by the standard filtration test. The test results showed that when time of filtration is same, the filtrate volume decreases linearly with the increase of content of polyanionic cellulose. When content of polyanionic cellulose is same, the velocity of filter loss decreases nonlinearly with the increase of time and the velocity of filter loss will reach a stable value. The filtrate volume in 7 to 8 minutes can reach half of the total filtrate volume. At the same time, the velocity of filter loss of drilling fluid decreases nonlinearly with the increase of viscosity. When apparent viscosity is between 3.5~4.15 mPa.s, decrease speed of velocity of filter loss is quick. The results are helpful for characteristics evaluation of filtrate loss of drilling fluid and control of filtrate loss.IntroductionDuring the process of drilling, water of drilling fluid can leakage into stratum, the water can result in instability and collapse of borehole wall. At the same time, the original ratio of drilling fluid will change. The density of drilling fluid will increase, the performance of the drilling fluid will change. Controlling amount of filtration is important to drill successfully. The additives of controlling filtrate loss are mainly two types, particle materials and polymer materials. High-molecular polymer is a kind of high-molecular material, has the adsorption effect, high polymer protection, can improve the advantages of slurry viscosity (Xu,2004 and Dehghanpour,2001). Some scholars carried out some study on the polymer material fluid loss agent in recent years, these study mainly focused on CMC, HEC, MHEC, CMHEC, starch and its derivatives(Zhang,2005 and Chevron,2009).About PAC (polyanionic cellulose) as drilling mud additives, a few of scholars carried out some relevant work. Plank (1992) applied PAC into ordinary freshwater drilling fluid and analyzed temperature stability of freshwater drilling fluid. Bennion (2000) applied PAC into drilling fluid and analyzed effect of polyanionic cellulose on strata inhibitory. Huang (2011) analyzed effect of PAC on properties of the high-density water-based drilling fluid. Mahto (2004) applied PAC into fresh water and salt-water drilling fluid and analyzed effect of PAC on rheological properties of the drilling fluid. Wang (2008) applied PAC into alkaline drilling fluid to study various performance of drilling fluid. PAC is a renewable resource and has good application prospect (Ankara, 2005). So it is very important to understand the effect of PAC on filtration process of drilling fluid.The test was conducted by changing the content of the PAC in drilling fluid. The object of this paper is to understand effect of polyanionic cellulose on filtration process of the low solid-phase drilling fluid."

Jan 1, 2017

By Denton A. Kort

Historically the visual examination of drilled shafts to determine shape was typically done under dry conditions. Many engineers believe that by using a dry method of construction, the question of shape is minimized because they can visually examine the excavation. In fact, test data suggests that slurry stabilized shafts tend to perform better than similarly constructed dry shafts. Clearly, the uncertainty of the shaft shape is magnified when constructed under slurry. Recent advancements have allowed a mechanical caliper to determine shape in wet conditions, but can be limited by certain shaft anomalies. New sonar technology can determine shaft shape, volume and verticality. The value of sonar technology to the geotechnical and foundation industry at large in terms of quality assurance for clients/owners and quality control for drilled shaft contractors is significant. This presentation will discuss the development and process of sonar calipering technology as it relates to the geotechnical and deep foundation industry. Sonar calipering results presented may include images from the following types of projects: slurry walls, bridge piers, cofferdams and secant walls. The results identify shaft anomalies in a variety of slurry environments, from water and polymer mixes through mineral slurries. Real-time in-situ images and CAD drawings will be presented illustrating the advantages of good caliper data taken during construction. This presentation will appeal to the geotechnical and structural engineers, as well as those supporting the deep foundation industry at large.

Jan 1, 2007

By Terence P. Holman

Instrumented load testing of high capacity micropiles, followed by detailed analysis and numerical modeling, provided an opportunity for real foundation performance to be incorporated into the design of a complex urban high-rise structure. This paper discusses a design-based load testing program and subsequent analysis for micropiles incorporated into a piled raft foundation beneath a portion of a high-rise residential structure in Brooklyn, New York. Preliminary numerical analysis, performed using the commercial finite element package PLAXIS 3D Foundation, indicated that soil stiffening and transferring heavy core loads to greater depths was required to minimize the total and differential settlements. High capacity micropiles were modeled below the tower core mat to create a piled raft effect, reducing the settlements to acceptable levels. Final design of the foundation and micropiles, and final numerical analysis of the proposed foundation system required an instrumented load testing program to provide the Owner and design team with a level of comfort. The instrumented load test provided data on the evolution of load transfer, including the mobilization of significant tip resistance, frequently ignored in design, and micropile axial stiffness. Final numerical analysis of the foundation system involved refining the PLAXIS model based on the micropile behavior and load transfer mechanism observed during the load test program. The authors believe that the combination of design-based load testing and numerical analysis in this project yielded a more refined foundation system with realistic expectations of performance.

Jan 1, 2007

By Bernardo J. Jiménez, Harlem Lora, Roberto Acosta Mora

Circunvalacion Norte project is currently the most important infrastructure project in Costa Rica. It is the last segment of the urban perimeter highway. Site investigation of local geotechnical conditions were studied by SPT, CPT, pressuremeter tests and boreholes. A static load test was executed as a proof test with an associated ultimate resistance of 12056 kN (2710 kips). Drilled shaft design was done using PMT tests and axial nominal resistance varied between 4000 kN (900 kips) and 6000 kN (1350 kips). A total of 416 drilled shafts were constructed in 15 months with drill performance of 32 m/day (105 ft/day). Drilled shaft lengths varied between 4,0 (13 ft) m and 40,0 m (130 ft). Selfconsolidating concrete was used to achieve an adequate workability even in high densities rebar cages. Several site conditions proved the importance for maintenance of the working platform, predrilling of rock sockets and having spare parts to avoid increase in project’s cost. New procedures were taken to prevent concrete segregation on excavations near underground water flow. Monitoring the quality of the shafts from CSL test showed less than 3% of the shafts presented a considerable anomaly, which proved that the adopted construction method and materials were adequate. For the concrete anomalies, successful remediation was performed by means of grout at the base of the shaft with two different types of drilling methodology depending on the concrete anomaly.

By Kirty Dave

Foundations in any contract are the most uncertain parts of the contract and most of the "Construction-Contract-Disputes" are either directly related to foundations or arise as 'Side-effects of changes in promises related to foundations. Foundation Engineering is defined as ' The art of selection, designing and constructing the elements that transfer the weight of structure to the underlying Soil or Rock." (Ralph B. Perk). This art started becoming a science since 1920, when scientific efforts to determine the behaviour of sub-surface materials were made. The art and science merged to give new techniques and the science started dominating the field as more and more refinement came in techniques to predict more accurately the characteristics of the sub-surface elements. Inspite of good thorough investigations and design, the contractual promises drafted could leave some room for differences between the parties and above all the prudency expected of both the parties may fall short of the expectations raised in the contract. This may give rise to disputes which may need to be resolved as per principles of law. This paper attempts to initiate a dialogue amongst Foundations-Engineers and Contractors as to how do we minimise the differences arising out of or related to contracts concerning "Foundations".

Jan 1, 1996

By Farhad Elmi

In this paper, a new procedure is used to find the bearing capacity of single piles and cone penetration resistance in soils. Although the procedure is mainly applicable to clay and sand using any plasticity model, this paper deals only with steady penetration in Sand. Cylindrical cavity expansion around the probe in a calibration chamber is modeled by finite element method using the HUJEUX elasto-plastic multi-mechanism model. The penetration resistance (qc) is related to cylindrical cavity expansion pressure limit (pL) using the method of Salgado et al. (1997). This procedure is tested using the results found in 3S/IMG calibration chamber. In this article the word "penetrometer" refers to both pile and cone.

Jan 1, 2002