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By Cheng Lin

The Group Equivalent Pile (GEP) approach was proposed by researchers to analyze a laterally loaded pile group. This approach enables engineers to evaluate the behavior of a pile group in single pile analysis software, such as LPILE. A previous study showed that the calculated results using the GEP approach for piles agreed well with field test data. To evaluate the accuracy of the GEP method for analyzing laterally loaded shafts, two case studies with different shaft diameters were performed in this study. The comparisons showed that the calculated results using the GEP method and considering the contribution of the shaft cap if embedded generally agreed with the measured from the full-scale tests.

Jan 1, 2009

By Amr M. Sallam

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

Jan 1, 2006

By Partha Sircar

"For Berth 22 modifications at the Port of Oakland, nearly 600 octagonal 24-inch ‘diameter’ precast-prestressed concrete piles were driven, some piles over 160 feet long. Prior to production pile driving, an indicator/test pile program was performed, which included extensive use of dynamic load testing with (Pile Driving Analyzer (PDA) & CAPWAP analyses. The indicator test-pile program resulted in requiring significantly longer piles than the original design based on subsurface borings. The cause of this discrepancy is investigated in light of the available geotechnical information, soil mechanics principles and standard techniques for pile capacity computations. Several interesting phenomena emerged. These include relatively low resistances offered by crushed rockfill than would conventionally be assumed, non-homogeneity of an apparently uniform formation and the effects of jetting on pile side friction. Also revealing was the significant increase in capacity between 1 and 3 weeks of driving for long piles in clay. Recommendations were developed for pile capacity for future use as “lessons learned”.IntroductionThe foundation for the replaced Berth 22 structure at the Port of Oakland in California involved driving approximately 570, 24-inch octagonal precast prestressed concrete piles. A plan and a section for the pile locations are presented in Figure 1.The ultimate loads on the piles used in the design are presented in Table 1 – the loads are quite heavy.The foundation design was followed by an extensive Indicator Pile Program. The contractors (Manson Construction Co. of Richmond, California) opted to use a Delmag D62-02 diesel hammer (Rated Maximum Energy – 165 kip-feet). Per the project specifications, the same hammer was used for both indicator and production pile driving. The production piles of appropriate lengths were ordered based on thr results of the Indicator Pile Program. A number of interesting results were found from the Indicator Program, which is discussed in this paper."

Jan 1, 2015

By Sandeep Pattnaik

Spring stiffness of soil and rock at different depth is often required for a pile structural model. If the pile is rested in multiple layers of soil, then it is rather more complex to simulate the soil in a structural model. The spring stiffness will vary based on density of soil strata over the depth. When a pile is socketed in weathered rock followed by a soil layer, a sudden change in subgrade modulus can influence the pile deflection drastically. Determination of soil spring and simulation of the pile in this condition required correct interpretation of subgrade modulus. The conventional approach of pile spring calculation underestimates the spring stiffness by ignoring underlaying stiffer layers. A finite difference method (FDM) of analysis can reasonably estimate the p-y of soil / rock based on subgrade modulus of each layer. However, the transition between the layers can be better simulated as per the deflection pattern of the pile. The lateral deflection of the pile is mainly dependent on the stiffness of soil layer surrounded by the pile. Generally, the lateral influence of a pile varies from 4D to 6D depending on the soil type. Therefore, soil spring stiffness around the pile would require special attention of a Geotechnical engineer to avoid uncertainty in the prediction of pile behaviour. In this paper, emphasis has been given to develop an approach for pile spring stiffness design. A standard software program LPile has been used to develop p-y curves of soil and rock layers at different depths and then converted to soil/ rock springs over the depth. Modulus of Subgrade Reaction as given in IS 2911 (Part2) was also used to correlate the spring value for different type of soil. Obtained analytical results were compared with full scale field trial for lateral deflection of pile. A good agreement between these two approaches has been established. The effect of soil structure interaction in the structural model shall be simulated by assigning an equivalent vertical and horizontal soil spring, which is developed by Winkler’s soil spring approach. A simplified design principle for calculating the pile spring is discussed in this paper. This approach has been extensively used in Mumbai metro elevated line pile design.

Nov 1, 2022

By David A. Staab

Numerical modeling was used to investigate the feasibility of using two geophysical imaging techniques, cross-borehole ground penetrating radar (XBGPR) tomography and electrical resistivity (ER) tomography, for detecting and characterizing defects in deep-mixed soil columns. XBGPR modeling was accomplished with a three-dimensional numerical forward modeling code and a two-dimensional inversion routine. Spatial variations in apparent dielectric constant (Ka) and attenuation (a) were mapped. Electrical resistivity modeling was accomplished with a three-dimensional numerical forward modeling code and a three-dimensional inversion routine. Spatial changes in electrical resistivity were then mapped. Three different types of defects were simulated, in addition to a defect-free column. The computer simulations suggest that XBGPR tomography and ER tomography might be useful, non-destructive methods for detecting and estimating the extent of defects in deep-mixed soil columns. The results show that small, isolated defects might be difficult to detect, but defects approximately equal to or larger than the sampling interval (for XBGPR) or vertical electrode spacing (for ERT) should be detectable.

Jan 1, 2004

By Tony D. Canale, Anthony Mazzo

"Times Square, arguably one of the best-known destinations in the world, has undergone and continues to undergo a re-development aimed at attracting corporate tenants to the area. Mueser Rutledge Consulting Engineers (MRCE) was involved with the planning, design and construction of the foundations for the Conde Nast and 5 Times Square sites, as well as Times Square Tower. These sites are pictured in Figure 1.This paper will focus on the design and construction of the deep foundations for Times Square Tower that was developed by Boston Properties. PROJECT DESCRIPTIONTimes Square Tower is 47 stories tall, with no setbacks and an overall height to top of crown of 730 feet (222.5m). It has two basement levels extending 30 feet (9m) below grade over the full site. As shown in Figure 1, the structure occupies the entire site and has a footprint of 22,000 square feet (2,044 m2), with a total rentable area of about 1.2 million square feet (111,480 m2). The planned use for the building is office space with retail at the ground level. When completed, Times Square Tower was the final building constructed as part of the Revitalization of Times Square. Due to the site constraints, designing and constructing the foundations was akin to placing the final piece of a puzzle.Times Square Tower provided numerous design and construction challenges that were a result of tight working conditions, heavy column loads, and a compressed schedule.GEOLOGIC SETTING AND SITE HISTORYThe Times Square area is part of the Manhattan Prong called the Manhattan Ridge, a formation of old and durable metamorphosed and folded bedrock, now termed the Hartland Formation. The bedrock generally has a thin soil cover and uneven surface overlain in some areas with a thin mantle of decomposed and/or weathered rock. Overburden soils include glacial and post-glacial deposits and recent fills.Transit improvements have been made in and around the Times Square area since the early 1900’s. The 1, 2 and 3 Subway Lines that run below 7th Avenue were constructed circa 1915 using cut and cover techniques and extend about 28 feet (8.5m) below grade. The N, R, Q & W Subway Lines that run below Broadway were also constructed in 1915 using cut and cover techniques and extend about 38 feet (11.6m) below grade. The 7 Line that runs below 41st Street was constructed later, using both cut-and-cover and tunneling methods as it runs below the other subway structures at a depth of about 55 feet (16.8m) below grade."

Jan 1, 2005

By Chris Sammon

The Block 75 portion of the City Creek redevelopment project in Salt Lake City required multiple shoring walls surrounding the 6 acre site constructed to depths ranging from sixty-five to ninety feet below original street grade. Shoring for the project was challenging due to site soils consisting of cobbles, sands and gravels, interlayered lakebed silty clay and fine sandy silt with incised stream deposits of silty/clayey sand and gravels combined with a high groundwater table. Moreover, several abutting structures each with a unique foundation system would be directly or indirectly supported by the shoring system. Three sections of interest are the shoring walls constructed at Main Street, Deseret Trust Building and Eagle Gate Tower. Main Street shoring extended to as much as sixty-five feet below street grade and utilized existing basement walls anchored in place in the upper zones with soil nail walls with pre-installed vertical elements for face stabilization below. Data are presented which illustrates the effect dewatering had on the settlement of the Main Street Shoring. The Deseret Trust Tower shoring supported a 12 story, historical masonry building. Site conditions dictated a separate design for the east side and the north side of the building allowing comparison of relative performance between these walls. Settlements of this structure were controlled by installing micropiles through the 90 year old structures spread footings. Shoring for the Eagle Gate Tower was to be constructed immediately adjacent to a mat supported 22 story high rise structure. This shoring system combined secant piles, ground anchors and incorporated existing abandoned-in-place pipe piles with infilling high pressure jet grouting to create a cutoff wall and eliminate the adverse impacts of dewatering below this sensitive foundation.

Jan 1, 2010

By George K. Burke

Single axis soil mixing is a mechanical method of blending soil in situ with a reagent binder to achieve improved character. Generally this achieves a design compressive strength or shear strength and/or permeability, but can be used to immobilize and/or fixate contaminants as well as a treatment system for chemical reduction to a more "friendly" substrate. The reagent binder can be a variety of materials, including cement, fly ash, slag, lime, and an assortment of additives. Usually this reagent is delivered in a slurry form (combined with water), but the Dry Mix Method uses pneumatic conveyance.

Jan 1, 2001

By C. L. Liao

The chief experiences for constructing deep tubular columns foundation under deep water are as follows: 1. P.C. tubular columns were sunk inside the caisson. 2. P.O. tubular columns of 3.6 M. diameter were sunk thru thick soil layer to a depth of 47 M. by vibrators. 3. The double wall steel cofferdam was sunk thru soil layer to a depth 31.3 M.. 4. Bore the bedrock with rotary drill succesfully. According to the successful experiences mentioned above, the deep tubular columns foundation may be constructed beyond 100 meters.

Jan 1, 2010

By David A. Jack

The Mission Valley Viaduct is located in San Diego, California. This structure is the intersection of Interstate 8 and 805. The project consists of the main viaduct, 8 connecting ramps, and one highway overpass. This job was originally built back in the 70's. After the Loma Prieta Earthquake in 1989, Caltrans began an aggressive program to seismic retrofit all of its bridges throughout the state. Most retrofit designs required major upgrades to the existing footings. These footing upgrades consisted of either driven or drilled shaft piling. The existing footings of the Mission Valley interchange were supported on driven H pile. The soils throughout the site were dense sands and gravels, cobbles, occasional boulders with a dense sandstone bearing strata, which varied through out the site. It was this sandstone strata that the engineers designed their pile tips around. High ground water in sandy soils created a high probability of liquefaction in all of the upper stratas.

Jan 1, 1998

By S. L. Karunakaran

Selection of an appropriate foundation system requires great skill and ingenuity on the part of the designer. Certain guidelines for choosing between a pile and raft foundation are presented. A number of methods are available for estimating the capacity of piles, giving a wide range of values for the theoretical load carrying capacity. A few aspects to be taken into account while arriving at an appropriate theoretical capacity are discussed. The effect of fluctuation of water table level on the pile capacity and method of accounting for this factor on the pile capacity obtained through initial load test are also discussed. A case study presents a comparison between the estimated values of capacity of piles and the values obtained through the initial load test.

Jan 1, 1996

By Q. M. Huang

In 1979 our company undertook the project of infra-structural work of White Swan Lake Hotel, (International class ) Guangzhou. Visit to the site showed that it was situated at the riverside, covering an area of 54,000 M2 with 30,000 M2 of which reclaimed from Pearl River. The material used for reclamation was black sand which was dredged from the nearby riverbed. The sand had the properties of high permeability and very low internal friction. The basement of the building was 6.2 m below ground level and 3 m lower than the riverbed. Apart from the pile foundation, a diaphragm wall was to be constructed prior to the commencement of excavation work for basement. A feasibility study was carried out to determine the method of construction which would maximize utilization of the plants and equipment that were available in the execution of the aforesaid foundation works. This report concerns only the construction of the diaphragm wall and the performance of the plants employed. A detailed delineation of the construction method is herein discussed

Jan 1, 2010

By Joseph A. Sopko

The first documented procedures for designing frozen earth structures are over 50 years old, implemented long before the introduction of the Finite Element Method (FEM). Since that time, the development of three-dimensional models has made the traditional and often over-conservative methods relatively obsolete. This paper discusses a new approach that is largely dependent on the analysis of internal stresses with the frozen structure and comparison to frozen soil laboratory tests. A specific design process is discussed related to initial field investigation, laboratory testing, structural and thermal analysis, and performance monitoring. The design results are compared to case histories in the field that verify the procedure. BACKGROUND One of the first documented methods to designing frozen earth retaining structures was by Sangar (1968). Methodical refinements were published by (Harris 1995) and published by the International Symposium on Ground Freezing in 2002 (Andersland et al. 1991). The structural design or thickness of the frozen mass was based on the unconfined compressive strength of the frozen soils. Two simple equations for determining the thickness of a frozen shaft are shown in Fig. 1 and the first two equations below.

Jan 1, 2019

By Miklós Kovács

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

Jan 1, 2002

By James P. Chivilo, Gregory R. Meeder, Scott J. DiFiore, Matthew H. Johnson

New construction in metropolitan areas has direct impacts on immediate neighbors and abutters. While noise and dust are generally nuisance concerns, demolition, vibrations, excavation, and dewatering can cause structural damage to adjacent structures. Different cities, states, or jurisdictions have different regulations that dictate requirements, roles, or responsibilities for varying parties during construction. The authors will introduce and discuss risks of new construction adjacent to existing structures, and the legal framework in Illinois which requires the owner of the new construction project to provide adequate protections for adjacent existing structures. The authors, who are engineers and attorneys, will discuss technical and legal concerns, and will highlight the importance of early and frequent communication among project participants to manage risks, despite whether or not any local regulations exist to drive the process. RISKS IN ADJACENT CONSTRUCTION New construction in metropolitan areas inherently involves some combination of noise, dust, ground-borne vibrations, earth excavation, and subgrade dewatering. These issues have potential to directly and adversely affect abutters and their property. Noise and dust can be nuisance concerns, while vibrations, excavation, and dewatering can result in damage to abutters’ structures. Noise and dust are unlikely to lead to physical damage to abutters’ property, and can be controlled with limited work hours and good housekeeping practices. Vibrations and excavations, however, if not well understood, planned for, and mitigated, can result in serious damage to abutters’ structures. In turn, this damage introduces additional and often significant costs and schedule delays.

Jan 1, 2019

By Takefumi Takuma, Hiroyuki Nishimura, Shigeru Kambe

"In order to achieve tubular pile driving with low noise and low vibration, the Press-in Piling Method has been adopted on many projects. The method utilizes reaction force derived primarily from previously driven piles to push in the next pile into ground. With attachments, the Press-in piling equipment can deal with hard soil as well as difficult site conditions. At West Toronto Diamond Rail Grade Separation Project in Toronto, Canada, the Press-in piling equipment drove more than 500 of 914 mm (36 inches) diameter tube piles in length of 12 to 25 meters (39 to 82 feet) to construct earth-retaining walls for railway grade separation. Myoshoji River Restoration Project in Tokyo, Japan drove some 600 of 1,000mm (39.4 inches) diameter tube pipe sections in length of 11 to 22 meters (36 to 72 feet) by the rotary Press-in piling equipment to increase the flood drainage capacity of an existing river in highly populated area of the city. Both projects exemplify the advantages of the method in urban settings.1. BACKGROUNDThe Press-in Piling Method was invented some forty years ago in Japan, where a very large number of construction projects were causing widespread construction pollution, especially by pile driving work in densely populated areas. The method has been providing solutions for piling projects which could not have been built otherwise due to the noise and vibration impact to the surrounding communities. The method can be used with various types of piles including sheet piles, tubular piles, concrete sheet piles and so on. With high pressure water jet and continuous flight auger attachments, the Press-in piling equipment can deal with dense sand, stiff clay, gravels, boulders and even soft rock without employing a different set of equipment."

Jan 1, 2015

By Julie H. N. Hampden, Per G. Reinhall

"Executive summary: Impact pile driving of steel piles is a common construction practice in freshwater and marine environments for the building of structures and foundations. This practice produces extremely high sound levels underwater that have proven injurious to aquatic fish and wildlife. To limit impacts to sensitive species, resource management agencies employ a variety of different strategies including timing restrictions to limit in-water construction windows to those months when there are low flow conditions in lakes or rivers, to those hours when tides are low, or to periods of the year when species of concern are least likely to be present in the project vicinity. In addition, permitting agencies have identified noise thresholds above which sensitive species could be injured, resulting in additional project conditions to curtail the extent of project noise impacts including: limiting the number of piles or pile strikes per day, requiring biological monitoring, and mandating the use of noise attenuation techniques, such as bubble curtains and cofferdams. Numerous studies have shown current noise attenuation techniques are costly and provide limited or variable noise reduction [1-3]. This is because the noise from pile driving is not only transmitted through the water column, it is also transmitted through the sediment back into the water column [1, 4-8]. Though these protective measures may help to reduce project impacts, they also result in additional complexity, expense, and potential risk for project delivery. Marine Construction Technologies, a Public Benefit Corporation, in collaboration with University of Washington and Washington State Department of Transportation, has developed a pile that can be installed with standard pile driving technologies (vibratory or impact hammers) and consistently decreases the total noise transmitted into the water. The double-walled pile is relatively quiet in comparison to unattenuated piles or existing noise attenuation techniques. This technology not only reduces the risk to sensitive species by minimizing the extent of potential impacts, it also reduces potential risks to project delivery by limiting the size of monitoring areas, minimizing the need to cap daily production rates, and eliminating the need for deployment of additional noise attenuation devices. Results from finite element modeling of the pile, scaled prototype testing, and full scale field testing in Commencement Bay (October 2014) and Vashon Island (October 2015) in Puget Sound, Washington indicate a reduction the peak sound pressure between 14 and 20 dB relative to single walled piles at a range of approximately 10 meters. These tests also confirm that the double-walled piles provide drivability similar to standard steel piles. In addition, preliminary calculations for capacity and structural characteristics demonstrate that double-walled piles provide equivalent or better performance than same-sized standard piles."

Jan 1, 2017

By Fredrik Sarvell, Harald. Ihler, Veli-Matti Uotinen, Jukka Rantala

"Many of the valid international building codes state that the lateral support provided by the soil is sufficient to prevent buckling of fully embedded piles. However, the development of small diameter micropiles and especially the use of high strength steel have evolved to applications including high capacity elements. The ultimate structural load bearing capacity of a pile in a cohesive soil is decided by examining which gives the lowest value, the peak buckling load and the resisting moment provided by the surrounding soil medium or the structural capacity of the pile cross section. In both cases, the initial deflection of the pile is a significant factor when the axial load bearing capacity of the pile is determined. Steel micropiles are joined commonly with mechanical splices. A less rigid mechanical splice is often a weaker hinge that allows the pile to bend and deflect more during installation increasing the initial deflection of a pile. In addition the less rigid splice element decreases the bending capacity of a jointed pile section and the ultimate axial load capacity of the entire pile. A series of FE analysis performed for various pile sizes suggest that the steel pipe piles including separate pile sections and mechanical splicing elements should have the combined bending stiffness of EIshaft = 0,75 × EIpile. This requirement yields to the buckling resistance of at least 96 % of the solid reference pile with the sameinitial eccentricity in similar soil conditions.IntroductionMany of the valid international building codes state that the lateral support provided by the soil is sufficient to prevent buckling of fully embedded piles. However, the development of small diameter micropiles and especially the use of high strength steel have evolved to applications including high capacity elements. The potential buckling of these very slender high capacity piles in soft soils may in many cases be the controlling design factor of the pile, especially with end bearing micropiles.A typical sequence of soil strata in Nordic countries, such as Norway, Finland and Sweden, constitutes of friction soil or dry crust clay on top of soft clay followed by till. This soil stratum often rests on solid bedrock of granite or gneiss. Conditions like these are suitable for slender end bearing piles subjected to buckling and especially steel pipe piles where most of the material is located at the edge of the cross section. Other reasons for using slender steel pipe piles are for example fast installation with minimal waste, efficient manufacturing and relatively well established design and execution procedures. Minimum quality criteria’s regarding splices for steel pipe piles are recommended to be set as national provisions to ensure quality and comparable procurements in foundation business."

Jan 1, 2014

By Nasr Sheta

"After Hurricane Sandy, the stability of an earth slope in the Atlantic Highlands, New Jersey in the United States was deteriorating due to slumping soils and erosion from flooding. A slope stability evaluation indicated the slope did not satisfy the requirements of the local building code. A triple-tier, pile-supported and mechanically stabilized earth wall was designed and constructed to stabilize the slope. The construction was planned from a 3-m-wide roadway and, because of rough terrain and limited work space at the site, a cast-in-place drilled-pile construction was deemed impractical due to slow pile production. An alternative procedure was utilized by pre-drilling holes, and installing precast tip-and-shaft-grouted (PCTSG) piles, which extended to competent soils to improve slope stability. A grade beam, connecting the PCTSG piles along with soldier beams and concrete lagging were used to form the lowest tier of the slope stabilization, while the middle and higher tiers were built as mechanically stabilized earth. The stability of the proposed stabilization was analyzed using 2-D non-linear finite elements. After construction, monitoring of the wall continued for about 8 months to check its performance, and indicated lateral and vertical wall movements were less than 25 mm and 6 mm, respectively, indicating effective slope stabilization.INTRODUCTIONStabilizing earth slopes using piles to connect near-surface unstable soils to underlying stable ground masses has been investigated by many researchers, who presented various approaches to evaluate the contribution of the pile system towards improving the stability of the slope. Some of these approaches consider the piles as structural elements receiving forces from the upper sliding ground mass and transmitting these forces to the underlying stable one. The force from the top sliding mass is applied at between one third and one half of the pile embedment into the top sliding mass, Anagnostopoulos et al. (1990), Fukuoka (1977) and Matsui et al. (1988). The point of application of the sliding force was explored based on successful case histories while addressing the safety factors for both geotechnical and structural design, Vessely A. et al. (2007). The development of numerical analysis techniques utilizing the method of finite elements (FE) also enabled better analysis and design of slopes stabilized using piles. A FE-based approach was successfully utilized to design slope stabilization with target safety factor based on the shear and bending demands and the spacing of the piles, Pradel D. et al. (2010).After Hurricane Sandy in October 2012, the stability of many properties constructed atop earth slopes located along the coast of the Atlantic Ocean has become a concern due to storm-induced erosion. This paper presents the analysis, design and construction of a hybrid slope stabilization system utilized at one of these storm-impacted properties, which is located in the Atlantic Highlands, New Jersey in the United States. The subject property consisted of a two-story residential dwelling and a parking structure, and was built on top of an about 8-m-high earth slope having crest at about elevation 10 m (el 10) and toe at about el 2."

Jan 1, 1900

By J. Matos e Silva

The paper refers five examples of executed diaphragm walls with one to five levels of anchorages. For each example a comparison is made between the results of the design using the traditional criteria and the Eurocode 7 recommendations. A comparison is also made with the behaviour of the diaphragm walls during the construction phase. From the referred examples the author presents his conclusions.

Jan 1, 2002