The presence of ferrisuperoxide dismutase (FeSOD) in several bacteria has been examined by determining the coincidence of ⁵⁵Fe radiolabel with superoxide dismutase activity using gel electrophoresis. FeSOD was concluded to be present in the matrix space of some gram-negative and gram-positive bacteria.

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The results of series field test on piles on strategic oil and gas site in Kazakhstan are presented in this paper. The test include: static load test in accordance with ASTM and Kazakhstan standards (GOST), dynamic load test in accordance with GOST and driving analyzer (PDA) in accordance with ASTM. The difference of standards procedures and test results is presented.

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This paper presents the determination of flow failure mechanism of very soft marine clay behind contiguous L-, (LP) wall with physical model tests. The with L-shape is model by applying pressure on -soil reduced scaled tests. The plane strain type is considered. One side of the model is transparent to observed movement of the soil and failure pattern during the test. The undisturbed very soft clay sample is collected, prepared, and tested near the site to obtain high quality undisturbed samples. The results indicated that the normalized ultimate pressure with undrained shear strength, Ph/Su reduces as the gap width increase. The relationship between Ph/Su and normalized gap width, sg/B, is proposed. The arch failure mechanism is observed from the recorded photographs. The ultimate resistances of LP are lower than the circular due to span length of arch over the open gap.

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This paper describes the development of cast-in-place concrete piles at the dawn of foundation technology in Europe and the United States. The first cast-in-place concrete

was the compressol invented in France around 1897. Around 1900, Raymond piles, simplex piles, and pedestal piles were invented in the U.S. Around 1910, franki piles were invented in Belgium. These piles have been installed not only in their home country but also in other parts of the world; more than 100 years later, they still support many historical buildings.

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 Steel piles below high-rise buildings may carry larger varying axial force generated by the overturning moment than those below low- or medium-rise buildings. On top of that, the subgrade lateral stiffness reduces drastically due to the soil liquefaction during a significant earthquake. Steel

’s horizontal strength may decrease due to the lower position of the inflection point. In this paper, centrifugal tests of the superstructure with high height-to-width aspect ratio, steel piles, and the liquefied soil system are presented. The collapse mechanism and the horizontal load bearing capacity of steel piles in the liquefied soil are clarified.

 Fig. 1 shows the model and instruments. The specimen consists of a superstructure with mass, a footing beam with mass, two bending plates, four piles, and a saturated sand layer. Table 2 shows specimen parameters, which are the height-to-width aspect ratio of the superstructure and the relative density of the soil. The centrifugal tests were performed under the centrifugal acceleration of 40 g.

 Figs. 5-18 show response time histories of Case 1-Case 6. The bending strain at the

head gradually increases toward the one side after the soil liquefaction and reaches the maximum value, ε_b,max. After reaching ε_b,max, the piles of all specimens collapse, except for Case 4. As presented in Fig. 20, in the case of the same D_r values, the sum of head’s shear forces, ΣQ_ph at ε_b,max are approximately equal regardless of the height-to-width aspect ratio. An additional shear force generated by ’s P-Δ effect, Q_PΔ,pl, accounts for the largest part in ΣQ_ph. On the other hand, in the case of high height-to-width aspect ratio, the value of Q_PΔ,pl is smaller issued from larger additional shear force generated by the superstructure’s P-Δ effect, Q_PΔ,s.

 Fig. 21 shows the relationship between

’s strength on the centrifugal tests and the M-N interaction curves of design criteria. Ratios of ’s varying axial force to ’s flexural buckling strength, N_pl/N_cr0, are the same until at ε_b,max regardless of the height-to-width aspect ratio. For piles subjected to the dead load and the varying axial compression force of all specimens, the combinations of axial force and bending moment at ε_b,max are distributed roughly following the ultimate strength curve as presented in Ref. 6. On the other hand, the results of the subjected to the dead load and the varying axial tensile force in the case of D_r=30% are lower bound to the M-N interaction curve as shown in Ref. 9 and those of the case of D_r=60% approximately reach that curve.

 As presented in Figs. 22-24 and table 3, steel piles’ collapse mechanism is concluded as follows.

’s bending moment reaches ’s full plastic moment, _vrM_pc,cr0, at the top and the bottom of the subjected to the varying axial compression force. In the case of D_r=60%, ’s bending moment also approximately reaches _vrM_pc,cr0 at those points of the subjected to the varying axial tensile force due to the increase of the distribution ratio of superstructure’s and footing beam’s shear force after at ε_yc.

 As shown in Fig. 24, it is concluded that steel piles’ horizontal load bearing capacity can be evaluated easily using steel piles’ horizontal strength based on the location of the inflection point in the liquefied soil and

’s plastic bending strength reduced by initial axial force.

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In the present study, the nonlinear coupled response of a 6- group with different arrangement of piles (length = 3.0 m and spacing = 3d, where d = diameter of = 0.114 m) are investigated under varying levels of horizontal harmonic excitation with a static load of 14 kN. Forced coupled vibration tests have been performed on the groups with 3 × 2 and 2 × 3 arrangements to obtain the time-acceleration responses for different frequencies of machine and finally from that the frequency-amplitude responses are determined for horizontal and rocking motions separately. The resonant amplitudes of the 3 × 2 group are found much higher (approximately 10 % for horizontal and 65 % for rocking mode) than the amplitudes of the 2 × 3 group. It is also found that the resonant frequencies of the 3 × 2 group are lower than the 2 × 3 group for all eccentric moments. The continuum approach with the formulation of group interaction matrix is used to determine the theoretical nonlinear dynamic response of the groups after incorporating boundary zone parameters and soil- separation lengths. The measured frequency-amplitude responses for both modes of vibrating displacements are compared with the results obtained from theoretical study. The resonant amplitudes (both horizontal and rocking) and resonant frequencies obtained from the analytical approach follow the same trends as observed in the case of dynamic test results. From the results it can be concluded that the effect of dynamic -soil- interaction is more prominent in the 3 × 2 group than the 2 × 3 group.

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Maintaining correct

’s verticality or inclination during installation, while ascertaining the safety of laborers and cost-effectiveness, is a key factor for construction survey. Traditional methods involve a significant amount of manual work, carried out using measurement rods and transits. Therefore, as more laborers are required, safety hazards also increase. Traditional Total Stations (TSs) have cross-hair reticles and are used for calculating coordinates and locations. Traditional cross-hair reticles in TSs are inadequate to measure structures that have pointed shapes, acute angles or no clearly identifiable center. Moreover, two laborers are required to take measurements when a prism is needed to indicate distances and angles. To solve these problems, a new reticle fashioned with concentric circles, was developed and incorporated to TSs. Moreover, new TS releases eliminate the need of prisms by developing a one-man operated device and incorporating the non-prismatic function. Baum Stations operation principle is based on aligning one of the circles in the Baum reticle to both sides of a . Measurements can be performed without centerline identifiers and at any inclination. Measurements can be performed even when there is insufficient distance to capture both sides of the , by capturing one point on the side of the .

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A three-dimensional numerical model is applied to the calculation of dynamic impedances of scoured groups embedded in layered soil deposits during earthquake. The group is modeled by means of beam finite elements and the soil is assumed to be a horizontally layered half space. The -soil- interaction and radiation damping are accounted for in the frequency domain by considering suitable Green’s functions expressing the dynamic force-displacement relationship at the nodes of elements. A parametric study to investigate the scour effect on dynamic impedances of 5×5 groups with various scour depths is discussed in this paper. It is found that the impedances decrease significantly as the scour depth increases.

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In this paper, the results of static horizontal loading tests of steel tubular piles installed by the Gyropress Method and the Press-in Method assisted with water jetting were collected, and the se horizontal bearing performance s were evaluated. As a result, the following were drawn: 1) Load-displacement curves of the Press-in Method assisted with water jetting and the Gyropress Method were consistent with the Weibull distribution curve, when the deformation index m=1.0. The average yield displacement normalized by the

diameter with the Gyro Method is consistent with the average values of 4.1 – 4.5 % for steel tubular piles installed by other construction methods, and that with the WJ Method gives smaller value than the average of other construction methods; 2) The coefficient of horizontal subgrade reaction calculated backward from the displacement at the loading point showed somewhat larger value than the design value when the reference displacement was set at 1 % of the diameter in the case of the Gyro method. On the other hand, for cases constructed by the WJ method, the average of measured kH is regarded fairly consistent with designed kH, but the variation of them are large; and 3) In the case of group piles, δg - kH curves were better fitted than δg / B - kH curves. The calculated backward kH approximately coincides with the design kH when the horizontal displacement at the ground surface is about 15mm.

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In soft ground, foundation is commonly used for heavy superstructures. Earthquake is a natural phenomenon that threatens the superstructures with foundation. Statistical data from past-experienced earthquakes like 1995 Hyogoken-Nanbu earthquake shows that the failure of foundation during a major earthquake happened frequently. Therefore, it is necessary to investigate the mechanical behavior of foundations at the ultimate state during a major earthquake and enhance its seismic behavior. An economical and effective method for improving the seismic performance of an existing foundation is partial-ground-improvement method. In this method, determining the size and the location of the improving area around the foundation is an important matter and it needs to be clarified. In some cases in spite of the partial-ground-improvement has been conducted, but there is less upgrading in the seismic behavior. In this paper, in order to find an optimum pattern for the partial-ground-improvement method, numerical analyses and 1g shaking table tests are conducted. In the numerical analyses and shaking table tests a soil- foundation-superstructure system is adopted. Consequently, the seismic behavior of an elevated bridge supported by group- foundation with three different patterns of partial-ground-improvement and one other pattern without partial-ground-improvement is investigated. Finally, an optimum pattern for the partial-ground-improvement method is proposed that can reduce the influence of earthquake on foundations. In the numerical analysis, 3D soil-water coupling elastoplastic dynamic finite element method with a program called DBLEAVS (Ye et al., 2007) is used. In order to numerical analyze the seismic behavior of the foundation, multiple factors like the soil properties, the foundation, the superstructure and the mutual interaction between these factors should be taken into consideration. Therefore, in present study the soil, the group- foundation and the superstructure are modeled with proper constitutive model.

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 Soil-structure interaction (SSI) influences the seismic response of buildings supported by

foundation. Under a significant input motion that causes damage to piles, the SSI is influenced by the nonlinear behaviors of the free ground (i.e. site nonlinearity), soil close to the foundation (i.e. local nonlinearity), and structural members (i.e. structure nonlinearity). The interaction among piles (i.e. the effect of groups) complicates local nonlinearity when two or more piles are installed in a narrow space. Experimental and analytical studies have indicated that lateral resistance per in a group tends to be smaller than that of a single , and depends on its location. However, few studies have conducted on lateral resistance of groups under load in the oblique direction. Therefore, this study aims to investigate seismic response of groups subjected to input motion in the oblique direction.

 The study consists of two steps. In the first step, a shaking table test and its simulation analysis are conducted to investigate influences of direction of input motion on dynamic behaviors of a structure supported by a

group. In the second step, a cyclic loading analysis on full-scale groups is conducted to evaluate hysteresis characteristics of -soil springs. The analyses are based on the nonlinear three-dimensional finite element method.

 

 The shaking table test was for a rigid body supported by a 5 x 5-

group. Piles were modeled using acrylic cylinders with a diameter of 12 mm and a length of 421 mm, and installed in the dry Toyoura sand deposit. Six types of input motion, which contains two different waveforms and three different amplitudes, were applied to 0-degree or 45-degree direction. The experiment provided following findings:

 1) The amplification characteristic of the soil-structure system did not depend on direction of input motions. This fact indicates lateral resistance of a whole of the

group does not depend on direction.

 2) Subgrade reaction of each

differed significantly depending on the location and the direction of input motion. This difference was considered to cause that of bending moment.

 

 The cyclic loading analysis was for a 2-

group, 3-, and 5- groups in the series arrangement, and 3 x 3- and 5 x 5- groups in the square arrangement. Piles had a diameter of 600 mm and a length of 10 m. Soil was assumed to be homogeneous sand deposit, and modeled using perfect elasto-plastic bodies governed by the Mohr-Coulomb yield criterion. The amplitude of displacement was gradually increased, and the loading direction was varied at the interval of 15 degrees. The analysis provided following findings:

 1) Maximum subgrade reaction and hysteresis dissipated energy of each

strongly depended on the loading direction. The relationship between these characteristics and loading direction differed significantly depending on location.

 2) Equivalent damping ratio of the equivalent single

did not depend on the loading direction as long as nonlinearity in soil close to piles progressed.

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A simplified analytical approach is proposed to study on the behavior of the piled raft foundation with rigid raft subjected coupled loads in layered soils. Employing the shear displacement method, based on the transfer matrix, the - interaction under vertical load is analyzed. Adopting the modified subgrade modulus, the head- head interaction under horizontal load is analyzed through the finite difference method. Base on solutions for stresses and displacement in layered elastic half space, the interactions between head and soil surface, soil surface and head, soil surface and soil surface subjected coupled loads are taken into account to determine the flexibility matrix of the group-soil system. Then the load-settlement relationship of rigid piled raft foundations subjected coupled loads, load and settlement of the piles along the depth are obtained. Comparison among the results of the finite element and the calculated results is carried out, and the feasibility of the present method for the analysis of piled raft foundation and the superiority of the modified subgrade modulus are proved.

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This study aims to assess the -group effect of spacing and parallel-spasing to the direction of loading in large displacement analytically. The analytical modeling used in this study is 2-D FEM model for the ground in consideration of the nonlinear characteristics. Major findings are as follows: (1) -group effect occurs by forming the isolated single a line in a parallel direction. The influence becomes remarkable in less than 5 times of diameter. (2) In the loading direction, it occurs by forming the isolated single in more than 10 times of diameter. The lateral resistance of lead is larger than subsequent piles, and it's larger than the isolated single . (3) The -group effects depend on a -soil- interaction.

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The additional

method is a technique used to reinforce existing foundations by piles and footings. The main problem with this method is that it takes a lot of time and effort to combine the existing foundation and the additional foundation. Another problem is that the design of this method cannot be sufficiently rationalized because the load share mechanism is unclear due to the generation of the group effect. The objectives of this study are to develop a new high-workability combining method and to investigate the load share mechanism of the reinforced foundation. In this paper, 1G seismic loading tests are conducted on group piles, namely, 4 existing piles and 6 additional piles. Then, a simulation analysis of the loading tests is performed. Finally, a parametric analysis that simulates the superstructure and the steel outer shell is conducted.

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The Quaternary alluvial deposits was widely distributed in the field of hydropower station, composed of the silty sand with mud, the silty sand and the gravel. The Quaternary alluvial was with the low average standard compaction number and the loose structure, high compressibility and low bearing capacity, particularly its saturated silty sand had the potentiality of liquefaction. According to these characteristics, the single mixed foundation was used to improve its bearing performance. There were series of static loading tests in situ with the different conditions including the three different ’s length and the two different bearing stratums.Combined with the data of numerical analysis, its failure modes were analyzed and both of the vertical ultimate bearing capacity and the characteristic value of bearing capacity were obtained. Study showed that: 1)when bearing stratums was the compacted sands or the gravel, the P-S curve was the gradually falling type with no steep drop and the P-Δs/ΔP curve had plain stage or sharp, 2)when length was 14.0m and 19.0m respectively, the failuer was resulted by the flaw，their ultimate bearing capacity by the static loading test was lower than the ultimate strength value of core of and the one calculated by the minimum combination, when length was 11.0m, it was controlled by the ultimate bearing capacity by the resistance from the soil surround and the resisitance from the ’s tip. The study was the foundation for the follow up tests of grid structure mixed composite foundation and as the reference for the similar engineering.

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Casting bored piles in Karst areas is often problematic, since the concrete can penetrate through cave systems or underground stream channels, resulting in poor construction quality of bored piles with insufficient bearing capacity. A new type of bored

is proposed to cast the concrete within a rubber/geotextile bag in the bored hole, which can restrict the loss of concrete through stream channels in Karst areas. In this study, model-scale laboratory tests were conducted to assess the feasibility of casting rubber/geotextile bag-sealed bored and to evaluate its bearing behavior. The measured results for a bag-sealed within Karst regions and a normal with equal diameter in a uniform ground without stream channels were compared. It demonstrates that casting bored within a big is an effective solution to increase the bearing capacity of under static loads. The ultimate bearing capacity of bag-sealed is about 1.5 times that of equal-diameter . The settlement of bag-sealed is much smaller than that obtained for equal-diameter under the same loading conditions.

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The aim of this work is to present a strut-and-tie model for design of reinforced concrete

caps. The model considers both failure by crushing of the compressed struts and by yielding of the tie reinforcement. Unlike some traditional models, crushing of the compressed concrete is not checked at the section in direct contact with the column base (column/ cap interface). In this work, crushing of concrete is verified in a section at a certain depth inside the cap. Thus, this verification is replaced by determining the height of the nodal zone at the top of the cap required not to cause crushing of the struts. An iterative algorithm is used for this purpose. Comparison with a large number of experimental results available in the literature demonstrates the effectiveness of the proposed model for the design of concrete caps. Numerical examples of practical use of the model are also presented.

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A new method is proposed to estimate the shape of a by vibration analysis. This is the first method proposed for a -shape estimation, which can be used to diagnose the integrity of a with an enlarged, subterranean base. It is demonstrated, and verified by experimentation, that -shape can be estimated by using an acoustic tube model. shape estimation by this method was found to be quite accurate for an experimental laid horizontally on ties, at ground level. This method could be used for estimating the shape of an underground , when the soil effect is removed from the measured vibration signal.

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This paper discusses an experimental study on the effects of soil plugging on the inner frictional resistance of bottom thick-walled open-ended piles. The piles were penetrated in both dense and loose sand, prepared by 60 and 30% of relatively densities respectively. Open-ended piles of 30 and 50mm outer diameters were used in the study. A sleeved and non-sleeved open-ended

each were used in addition to the respective closed-ended piles. The sleeve height of the sleeved open-ended piles was designed as a 2D length (D is outer diameter). The degree of soil plugging is discussed using the incremental filling ratio. The results suggest that the loose ground is more effective to use the bottom thick-walled open-ended piles regardless of the diameter. The results also indicate that the larger diameter piles are more effective to use the bottom thick-walled open-ended piles. The results of soil plugging indicate that the influence of ground density is not significant in relatively smaller diameter piles than relatively larger diameter piles.

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When steel piles experience the higher axial compression force caused by the superstructure’s overturning moment in the liquefied soil, the

’s flexural buckling may occur. In previous papers, the steel piles’ collapse mechanism is presented. On the other hand, the CFT piles may fail when they experience the significant earthquake in the soft ground. In this paper, the centrifugal tests of the superstructure, the CFT piles and the liquefied soil system are conducted and the piles’ ultimate mechanism is clarified. Moreover, the ’s ultimate strength is evaluated using M-N interaction curves, to which the ’s elasto-plastic buckling strength is applied.

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