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"Premissas BásicasCaracterísticas do concreto centrifugado(Spun concrete characteristics)Aplicação em obras de engenharia de fundações(Application engineering works foundations)Logística de fabricação e transporte(Manufacturing logistics and transportation)Emendas x uso de aplicação(Amendments x use application)Geologia brasileira, da região costeira a presença de grandes bolsões de argila mole(Brazilian geology, coastal region the presence of large pockets of soft clay)Influencia do sistema de cravação(Influence of driving system)Transferência da Energia Aplicada(Applied Energy Transfer)Estacas longas(long piles)Controles executivos (diagrama de golpes, nega, repique elástico, ensaios de carregamentodinâmico, provas de carga).(Executive Controls (blows diagram, sets, elastic rebound, dynamic load tests, load tests).)ECD – aplicação da metodologia do DIETECD - application of the methodology DIETBrazil has a highly variable geology all along its coast that directly influence the choose of foundation type, being too employed the use of reinforced spun concrete piles initially ranged in diameter from 60 to 80 cm. Over the past 10 years with the advent of investment in marine works projects began to demand a new range of piles with diameters greater than 100 cm and in the absence of amendments.On land is also very remarkable the presence of regions with large layers of soft clay, in prime areas that have been explored. A classic example is the Barra da Tijuca in Rio de Janeiro that has suffered from the housing boom growing toward these regions. In these regions it has been very common driven lengths of about 40.0 meters, which basically go through thick layers of soft material or unconsolidated and they will find strength in depth with residual soil layers or even the bedrock.The spun concrete has great qualities for application in deep cuttings resulting from the production process, which gives a redistribution of fresh concrete mass collaborating with the particle size distribution effective loss of water that is thrown to the center stake being subsequently discarded. Consequently this contributes to a reduction in the factor a/c that is directly connected to increase strength.The fact that there is a sort of concrete helps to reduce voids in the mixture, which increases the durability characteristics. This condition made it possible to employ the spin technique on poles, which are directly linked to aggressive media in large urban centers.Another very attractive feature is that the centrifuge process can work with concrete with the lowest percentage of mortar and more gravel. This concrete mix directly contributes to increasing the specific modulus of elasticity, thus allowing a greater capacity to absorb the energy of the blows transferred with less deformation.Despite the great potential of land application of prefabricated spun concrete stakes there are only three factories and its limitation is the cost of transporting manufactured for the various regions, since all transportation is done by road.For its transportation is carried out exclusively by trucks, this limits the size of cuttings being produced commonly in length from 11.0 to 12.0 meters in length and smaller compositions. For use in long piles of works is resorted to amendments in the form of metal rings, concreted near the ends of the stakes, with the transfer through steel bars in CA-50 welded to the ring. Usually run in steel ASTM A-36. Later in the work these rings are welded with coated electrode.In the case of maritime stakes are very used to drowned splicing technique, which basically consists during the spin process leave one end with the armor of the apparent stake and work together two elements and make specific, with superior resistance to the prefabricated stake.This study in addition to briefly introduce the process of manufacturing, design and logistics presents a detailed study of applicat"

Jan 1, 2015

By Ambarish Ghosh, Subhaprasad Chakraborty

"Construction of basement floors has become necessary to meet the requirement of parking in office and residential complexes and in hospitals for radiotherapy treatment. Important projects coming up in Kolkata are mostly in closer proximity of residential buildings, office buildings and historical monuments. Sheet piling is mostly used as temporary shoring system during construction. Deep excavation in urban environment creates great problem related to construction induced vibration due to driving of sheet piles for basement, pile driving etc. which raises the chances of damage of adjacent buildings and nearby structures. Vibratory sheet-pile driving is the most common method of sheet pile installation. The knowledge of induced vibration due to this phenomenon is still very deficient. This paper presents the analysis of measured vibration data collected from different sites of Kolkata with varying soil profile. Typical two case studies of sheet pile and pile driving has been presented and the vibration values are analysed. The responses of the vibration are reported in terms of peak particle velocities (PPV). To evaluate the effects of vibration due to pile driving two aspects have been considered: the effect of the energy entering the ground from the pile and the effect of the soil condition.INTRODUCTIONIn urban areas infrastructure development projects are mainly located adjacent to existing structures like residential buildings, offices and historical structures. The construction work of such project influences the surrounding environment as well as human perception (Wiss 1981). During the construction of basement for residential complexes and hospitals sheet piling is mostly used as temporary shoring system or as to support the earth mass. The vibration induced due to driving of piles and sheet piles have been presented herein. Deep excavation projects close to existing structures increase the concern of environmental impact. For this reason the vibration assessment and prediction has become a subject of great interest. It is important to develop a site specific model for predicting the ground vibration resulting from pile and sheet pile driving at the construction sites. The developed model gives the efficacy to guide the engineer to select the construction methodology ensuring the safety of the surrounding structure. The model developed here is site specific and the parameters that has been used are dependent on the soil condition and the energy source."

Jan 1, 2015

By Silvana B. Foá

Results from full-scale loading tests showed the use of the dynamic increasing energy test (DIET) to verify the capacity of deep foundations. This method allows the measurement of dynamic resistance - displacement curve and the prediction of the static resistance -displacement curve of the pile-soil system. The comparison between the use of DIET versus the static load test is also considered herein. This work was divided in two different phases, the first accomplished in Salvador (Bahia) and the second in Brasilia (Federal District), both in Brazil. The first phase consisted of field loading tests carried out on piles comprised by an approximate 10 to 12 meters thick deposit of fine saturated sand, overlying a stiff clay layer, which is found in certain areas of the Brazilian Northeast. Two metallic (rail track) piles were field loaded in this site. One of them was dynamically tested and the other was statically tested. The second site belongs to the Post Graduate Program of the University of Brasilia. It is comprised by an approximate 8 to 14 meter think deposit of porous clay, overlying a hard strata of saprolitic state. In this site a unique precast driven centrifuged pile was tested. The DIET procedure has demonstrated to be a tool of fast execution and low cost (if compared to static load test). It is a promising procedure to evaluate the behavior of pile-soil system.

Jan 1, 2002

By Naim Noori Samie

Lateral force rsistance of piles is analytically investigated by dividing the pile length to 3 segments. The first segment (Zone I) models the load eccentricity with respect to the soil and the pile-deck connection, using a third degree differential equation representing the shear variation along the pile. The soil is assumed to be uniform, homogeneous with an elastic-perfectly plastic behavior. The Top soil layer (Zone II) is assumed to be stressed beyond the elastic limit. A simple 4th degree differential equation represents this zone. The soil resistance is assumed to vary linearly with depth (or surcharge). The pile deformation and soil behavior determines the plastic zone length. In zone III the soil is assumed to behave elastically, hence its resistance is proportional to its deformation. A linear 4th degree differential equation is employed in this zone. The compatibility conditions are satisfied on each boundary. Maximum allowable moment and shear are investigated throughout the pile as the basic limiting criteria on lateral force capacity. In this paper the soil coefficients are taken from a proposal by ref(3), and the results are compared with the soil response as determined by the P-Y method as recommended by ref(2).

Jan 1, 1996

By Emad Farouz

This paper presents a case history of a successful construction-phase pile load test program that optimized the pile design in challenging ground conditions at the Great Neck Wastewater Treatment Plant in the Town of North Hempstead in Nassau County, New York. The improvements and expansion of the wastewater treatment plant included the construction of several new structures to comply with new stringent nitrogen discharge requirements and new design flow. The challenging ground conditions included up to 20-ft thick organic deposits with weight of hammer blow counts and up to 14 percent organic content and tidal ground water that was near the ground surface. The foundation design evaluated various deep foundation alternatives and selected driven closed-ended pipe piles then filled with concrete as the most suitable foundation. The selection process included considerations of cost, risk, vibrations, noise, and schedule. The contract documents utilized an innovative approach of performing an optimization load test program that was implemented during construction to optimize pile lengths and reduce potential vibration and construction schedule. This paper discusses the details of the successful load test program including static testing, dynamic testing, and the innovative contracting approach utilized to implement the construction phase load test program. It also discusses the successful development and implementation of driving criteria for production piles and construction challenges. The successful load test program resulted in savings of several hundred thousand dollars, optimized schedule, and lower environmental impacts.

By Jim Cook

Arsenal Football Club required the development of a new home stadium in north London, subsequently named the Emirates Stadium. The proposed development comprised a 60,000 seat stadium, with associated facilities and a sports training centre. Described are the foundation solutions and piling construction techniques used, which take into consideration the potential impacts on existing above and below ground railway infrastructure and underground water structures. Methods used by the piling contractor to improve aspects associated with health, safety and quality are also described.

Jan 1, 2008

By X. M. Wu

The paper describes four different types of support for deep excavations, which are currently used in China. Local experiences were illustrated by presenting case histories for each type of support. For braced excavation in soft clays in Shanghai, the earth pressure against bracings were found to be in conformity with the trapizoidal estimation given by Terzaghi and Peck (1967). For tie-back support of excavations in Beijing and Shengyang, earth pressures were found to be much less than those predicted by ordinary rules. In the construction of a mining shaft in coarse sand below ground water level, high pressure jet grouting has been successfully used to form a circular impervious lining of the shaft. As an effective anti-slide measure, large diameter reinforced concrete piles constructed by open shaft method have been widely used with success.

Jan 1, 2010

By Leonardo Massone

The p-y method is one of the most popular methods in pile design and has been calibrated for various boundary conditions using numerical and experimental studies during recent years. Most studies on reinforced concrete (RC) piles have included the impact of flexural nonlinearity, (e.g. nonlinear moment?curvature relations) but not considered associated pile shear deformations when deriving p-y curves from field data. Common p-y curves may be better applicable for piles with flexure dominated failures (e.g. piles with free- head boundary conditions). For piles with fixed head boundaries (i.e. rotation restrained piles) shear deformations could be of significant influence. To study this problem, a coupled shear flexure interaction model for axial-bending-shear behavior coded in OpenSees is applied to a 0.61 m flagpole and a 0.61m fixed head pile specimen to investigate the possible influence of shear deformations to the overall pile responses. The surrounding soil is represented by p-y curves derived from prior large scale testing on piles with similar boundary conditions. Analysis results show that for flagpole piles, shear forces and shear deformations were insignificant. Considerable contributions of pile shear displacements and forces were observed for the fixed head pile, with shear displacements contributing up to 40% of the total pile displacement. Results suggest that nonlinear shear deformations for reinforced concrete piles should be considered for fixed-head or similar conditions, and that currently used p-y curves may underestimate the actual lateral pile displacement and possibly lead to unsafe design for the particular boundary condition.

Jan 1, 2011

By John R. Davie

This paper describes the design and construction of two 5.6 MN capacity drilled piers installed to support the main loading elements of a large cantilevered gantry crane. The critical crane columns were located within and at the edge of an existing sheet-pile cofferdam, which had been filled with loose coal slag when it was originally constructed Due to the presence of the slag and the age and questionable condition of the sheet-piles, the drilled piers were installed to provide vertical and lateral supports for these columns. The lateral capacity of the piers was supplemented by two smaller drilled piers and two large spread footings that were linked by a system of grade beams.

Jan 1, 2006

By Hitoshi Ogura, Koichi Kobayashi, Sadao Yabuuchi

"In Japan, most pile foundations using pre-cast concrete piles are installed by the bored pre-cast piling method, wherein pre-cast piles are installed in holes that have been excavated beforehand and filled with cement milk (term used for cement water slurry in Japan). The bored pre-cast piling method with enlarged base, in which the portion near the toe is enlarged during boring operation, is widely used because of the cost benefits and the increased vertical bearing capacity that this method offers.The EX MEGATOP method, further developed as an improved bored pre-cast piling method with enlarged base, is reported here. The features of this method are: (1) High vertical bearing capacity; (2) High degree of freedom in design; (3) Excellent workability; and (4) Friendly to the environment. In particular, high vertical bearing capacity can be obtained using nodular piles and by enlarging the area at the pile toe and shaft. This method can gave a vertical bearing capacity coefficient at the toe of a=430, more than twice the corresponding value of a = 200 of a conventional bored pre-cast pile. Moreover, the shaft resistance can be several times larger than that of a conventional bored pre-cast pile. This report gives an overview of the EX MEGATOP method, evaluation of vertical bearing capacity, and examples of application of the method.1.lntroductionMost pile foundations in Japan are installed by the bored pre-cast piling method, that is, in holes that have been excavated beforehand and filled with cement water slurry, referred to as 'cement milk'. The ""bored pre-cast piling method with enlarged base"" is frequently used. In this method an enlarged excavation is used near the pile toe to increase the vertical bearing capacity.The EX MEGATOP method is a variation of the bored pre-cast piling method. Its features include the use of nodular piles and a long, enlarged excavation. The vertical bearing capacity of the EX MEGATOP method is described in this report."

Jan 1, 2005

By William Siegel

Kleinfelder provided foundation analysis and design for an expansion to a cement plant in Florence, Colorado. The expansion was a conversion from a horizontal wet process to a vertical dry process, and resulted in the construction of a number of structures with heavy foundation loads. [ ] The field investigation identified old fill and saturated sands and gravels above a shale/limestone bedrock environment. Based upon the anticipated loading, drilled piers socketed into bedrock were recommended. The structures were constructed in accordance with the design recommendations.

Jan 1, 2007

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 Robert J. Carle

This paper reviews a variety of highway structures which have been built using steel sheet piling as the permanent structural elements of bridge piers, abutments and wingwalls. Those structures built over the past 20 years in Europe include major highway bridges over railroads, highways and waterways in both urban and rural locations. Most highway structures built in the United States using steel sheet piling have been limited to secondary roads in rural locations. The main thrust of this paper is the presentation of various design concepts for highway structures which utilize steel sheet piling. The main purpose is to challenge the profession to move forward from this conceptual presentation and to develop the details necessary to provide safe, cost-effective structures which go well beyond the scope of those being built in the United States today.

Jan 1, 1989

By Nabil F. Ismael

Load tests were carried out to examine the ultimate bearing capacity of short, large diameter bored piles in connection with the construction of a multistory building on the Arabian Gulf in Kuwait. Testing included 0.45 m, 1.0 m, and 1.2 m piles installed through loose sand into a bearing stratum consisting of very dense cemented sands. All tests were carried out to failure. The base resistance and shaft friction were calculated using the Meyerhof method for a layered soil profile. The method employs the standard penetration test N-values. The results indicate that the piles are end bearing piles with a great portion of the pile capacity due to base resistance. The mobilized skin friction is small. The calculated pile capacities were very close to the measured values with the maximum difference not exceeding 10%.

By David J. Puller

As part of the value engineering process on a major Design Build highway project, instrumented trial pile load tests were used to achieve savings in cost and time on the foundations for a major river crossing. Two trial piles were tested close to failure load at 25MN. Following the interpretation of the pile load test results which included the determination of the ultimate shaft and base capacity, the mobilisation of the shaft and base resistance with pile displacement, and correlations with vertical effective stress and SPT profile, a revised design methodology was proposed. A 25% enhancement on commonly assumed ultimate shaft friction in Chalk was adopted. In addition a significant reduction in the Factor of Safety on end-bearing capacity generally used was also implemented. The revised design resulted in a significant cost and time saving on the piling operation with the pile length reduced by up to 6m (approx. 20%) for the river piers.

Jan 1, 2002

By Darrell L. Beddard

The test program information provided for some immediate changes on the upcoming contracts and in contract administration for the I-880 Replacement Project. Plan sheet modifications included changes to the pile data tables showing the actual demand load required for structural stability. The normal class of pile with a minimum load carrying capacity was removed. This provided for substantial pile length reduction at several locations since the structural loading was much less than the predetermined pile class ultimate capacity. New specifications were developed and standard specifications were modified to accommodate the newer foundations, installation procedures and pile acceptance criteria. Current Caltrans specifications require that the Contractor provide bearing capacity at the specified tip elevation. This requirement was removed and pile acceptance was determined by the Engineer. Acceptance criteria was established by the State and was based on. set-up trend over time. Static loading tests were reduced especially in areas where testing was performed on the indicator program. Testing procedures were modified and set-up periods were established before piles could be tested. For the contract near the San Francisco Oakland Bay Bridge (Unit E) the FHWA 1000 tons (8.9 MN) test beam configuration was completely changed. This provided added safety and allowed more tolerance in the pile placement for the testing operations. Indicator piles were added as companion piles to the static loading test piles. These piles were used for restrike events which included collecting dynamic data for calibrating the wave equation analysis with static load test results. Indicator piles also provided quick access for restrike events, where as, the static loading test pile needed modification to perform the restrike operation. Penetration rates were recorded for these operations. Wave equation Analysis Program (WEAP) was used in developing the acceptance criteria. The standard Engineering News Record (ENR) formula in the current Caltrans' Standard Specifications was removed for the contracts. Contractors were required to submit, prior to driving piles, a driveability study for their contract. These studies required discussion of their operations, method of installation, effects of soil set-up, set periods, hammer settings, bearing graphs, inputs to the WEAP program and complete a "Pile and Driving Equipment Data" form. Dynamic monitoring was detailed in the specifications on how the monitoring process was to occur. Set periods were established and restrike events were called out with the frequency of these events.

Jan 1, 1996

By Frank Borda

Two recent projects were completed in Ontario, Canada for major hospital additions that involved excavation support of heritage masonry structures. Conventional continuous caisson wall schemes were replaced, with significant cost savings, by tied back shotcrete systems. Using a combination of conventional design and FLAC analysis, excavation support was designed to permit excavation in competent to weak soils that limited horizontal movements of the existing structures to between 3 and 8 mm. The use of vertical wall elements (micropiles) integral to the shotcrete wall to support both the vertical wall loads and the face of the excavation was deemed to significantly reduce lateral and vertical wall movements. FLAC analysis was used successfully to predict wall movements and optimize design. The shotcrete method proved to be flexible and adaptable to design changes during the project. This permitted convenient accommodation of changes to the building geometry after excavation support had commenced. In addition the method accommodated staged demolition and excavation support of portions of the existing structure at low cost, conveniently and without delays.

Jan 1, 2004

By Ben C. Gerwick

Large diameter steel tubular piles installed vertically or on a slight rake, offer many advantages as the foundations of major overwater bridge in regions of high seismicity. By proper selection of diameter and wall thickness, an optimum balance between stiffness and strength can be achieved. Under strong seismic motion, the piles will deflect and bend so as to reduce the acceleration forces transmitted to the superstructure, while still limiting drift. A major advantage of this concept is that the mass of the footing block is significantly reduced from that of the conventional pier. The design of the footing block requires great care in order to transfer the high shears and moments. Where the soils consist of significant depths of sediments, the kinematic interaction of soils, piles and structures must be considered. Moments will be a maximum just under the footing block. Filling the top portion of the pile with concrete will prevent local buckling and assure ductile behavior even under overload. Typically the piles will be long, with most or all of their support furnished by friction and will require the use of very large pile hammers to achieve the required capacities. Where the piles are founded on rock or in hardpan, sockets will be drilled and filled with reinforced concrete. For these piles, high moments can occur both at the head and just below the rock surface, so the concrete infill should extend the full length. This paper describes the use of tubular piles driven through the deep silty sands of the Jamuna River, Bangladesh, and also where socketed into the near-surface rock for the mail pylon pier of the new San Francisco-Oakland East Bay Bridge in California.

Jan 1, 2013

By Peter Smith

One New Change is a landmark retail / commercial development in the City of London. Integral to the structure is the three double storey basement from which the building is serviced. The building construction involved a ?top down? (up down) construction technique to give programme benefits. In addition, the planning authority stipulated that 10% of the energy demand had to be met by Renewable technology. Cementation Skanska has not only delivered the foundation package - comprising secant piling and foundation bearing piles including Cemloc® plunged columns - but, alongside subcontractor Geothermal International, also installed a 1.7MW ground source heating and cooling system using Energy Piles® and open?loop wells to provide the renewable energy. The works were successfully installed and completed within a tight programme, and within the logistical constraints imposed by an inner-city location, concurrent demolition works and multi contractor involvement in the basement construction.

Jan 1, 2010

By Gerry Houlahan

The east span of the 3.5 km long SF-Oakland Bay Bridge is supported by different types of foundations along its span. Starting from the west, its first 460 m section comprising twin concrete box-girders is supported by sands and rock on Yerba Buena Island. A 620 m long steel suspension span then bridges a 25 m deep channel that is formed in sediments overlying rock. Twin concrete box girder structures, each 2.4 km long, complete the stretch over the remainder of San Francisco Bay to the engineered earth fill landing at its east end. For most of its length, the Skyway bridges water 3 to 10 m deep over soft surficial Young Bay Mud. The foundation types include spread footings with hold-downs, steel and concrete piles that are set in drilled rock sockets up to 3 m in diameter and 2.5 m diameter steel tubular piles driven to penetrations of up to 100 m. The design and construction-related considerations are presented. The different foundation types, influences of the site geology and earthquake demands on the substructures are discussed. The seismic motions of the bridge superstructures and substructures, as well as the depth-varying soil motions, influenced the foundation design. Together with performance-based design criteria, including post-earthquake footing displacement limits, these seismic demands influenced various aspects of the foundation design, including the use of battered and vertical piles.

Jan 1, 2013