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Effect of Relative Stiffness of Beam Column Joint on Internal Forces in Reinforced Cement Concrete Structures

Effect of Relative Stiffness of Beam Column Joint on Internal Forces in Reinforced Cement Concrete Structures

3) As the grade of concrete is increased in the beam, the depth required for the beam section decreases. Hence the area of steel required for the beam section increases. As the grade of steel is increased, the depth required for the beam section increases. Hence the area of steel required for the beam section decreases for the given flexural strength. As the grade of concrete increased for column, the area of steel required for the column section is increases. As the grade of steel increased, the area of steel required for the column section is reduces for the given axial forces. 4) Due to the variation in the moment of inertia by equivalent area method and gross area method, it will affect the relative stiffness of the beam column joint and internal forces. Hence the bending moments in the inner and outer frame varies from 1-3%. Moment in the inner and outer frame at the exterior support decreases in the equivalent area method than the gross area method, where as in the interior support increases. This variation because of the relative stiffness of beam column joint. Hence there is no larger variation in the bending moment we can safely use the gross area method for time saving.

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Foundation Relative Stiffness Effects in Sand under Static Loading

Foundation Relative Stiffness Effects in Sand under Static Loading

The modern foundation construction uses the new available construction materials that totally change the relative stiffness of the footing structure – soil interaction such as geocell, and waste [5]. However, using footing – soil system that is not stiff (rigid) enough, makes the foundation with a flexible soil interface. Therefore, it is obviously interesting to study the effect of foundation-soil interface stiffness on its ultimate load, settlement and failure mechanism that have not yet covered by the common bearing capacity theory. Conventional bearing- capacity analyses were produced to deal with rigid footings and consequently are ignored the effect of reduced foundation-soil interface rigidity [4]. A change in the relative stiffness of a footing affects the deformation of a granular media and particular analysis will be taken into the load-displacement behaviour, failure mechanisms and velocity fields. Granular materials are ubiquitous in our daily lives but have not been studied as much as standard fluids and elastic solids so a lack of understanding in their behaviour exists, there is no continuum model to predict their behaviour under loading [6].

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Effect of Relative Stiffness of Beam Column Joint on Internal Forces in Reinforced Cement Concrete Structures

Effect of Relative Stiffness of Beam Column Joint on Internal Forces in Reinforced Cement Concrete Structures

column is traditionally considered a rigid connection which actually not fully rigid and therefore accounted an extra moment leading to structural over-design and subsequently higher cost of beam construction. In this project the study is carried out for the effect of relative stiffness of beam column on internal forces in reinforced cement concrete structures. The structure geometry was 4m X 5m and G+2 building was analyzed using STAAD.Pro Software. The frame of 4m with 3 bays was considered for the study. Increased in the grade of concrete, the relative stiffness of the beam column joint varies. The effect of grade of concrete and steel on the flexural strength of beam and on the compressive strength of column was studied. The comparison of the bending moments for different grade of concrete and by the methods of moment of inertia was studied.

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Effect of Relative Stiffness of Beam Column on Joint Rigidity

Effect of Relative Stiffness of Beam Column on Joint Rigidity

The role of the beam-to-column connections in overall frame behavior is additionally of interest. These connections could also be created using bolting or fastening relying upon the sort of jointing technique and parts wont to build the joint, the flexibleness of the joint might vary from hinged to rigid joint condition. The moment at the joint, M might vary between rigid joint moment, Mr [Fig 1.2(a)], and zero value [Fig 1.2(b)] and also the relative rotation between members at the joint, Ɵ, might vary between zero [Fig 1.2(a)] and hinged joint rotation, Ɵh [Fig 1.2(b)].

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Comparative Analysis of Square Shape RC Frame by Replacing Masonry from Strut using Response Spectrum Analysis

Comparative Analysis of Square Shape RC Frame by Replacing Masonry from Strut using Response Spectrum Analysis

well as external walls of the building to fill the gap between RC frames. Non-structural member may provide considerable stiffness to the building and hence may improve the performance of the RC building during ground motions. But In most of the cases, the ignorance of this property of masonry in designing of the RC frame may get an unsafe design. The effect of ground motion on RC frame building has been carried out by considering with and without the stiffness of infill wall. A comparative study is carried out with RC building using Equivalent Lateral Force method and Response Spectrum method. The masonry infill has been modeled as an equivalent diagonal strut. Response spectrum analysis is performed by using ETABS by replacing the masonry by equivalent strut for G+8 reinforced concrete frames for constant relative stiffness and the strut is reduced up to 50% and behavior of the structure is observed . The parameters such as time period, base shear, storey displacement and storey stiffness are obtained and compared.

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Comparative Analysis of Square Shape RC Frame by Replacing Masonry from Strut using Response Spectrum Analysis

Comparative Analysis of Square Shape RC Frame by Replacing Masonry from Strut using Response Spectrum Analysis

well as external walls of the building to fill the gap between RC frames. Non-structural member may provide considerable stiffness to the building and hence may improve the performance of the RC building during ground motions. But In most of the cases, the ignorance of this property of masonry in designing of the RC frame may get an unsafe design. The effect of ground motion on RC frame building has been carried out by considering with and without the stiffness of infill wall. A comparative study is carried out with RC building using Equivalent Lateral Force method and Response Spectrum method. The masonry infill has been modeled as an equivalent diagonal strut. Response spectrum analysis is performed by using ETABS by replacing the masonry by equivalent strut for G+8 reinforced concrete frames for constant relative stiffness and the strut is reduced up to 50% and behavior of the structure is observed . The parameters such as time period, base shear, storey displacement and storey stiffness are obtained and compared.

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An investigation into the relationship between rocker sole designs and alteration  to lower limb kinetics, kinematics and muscle function during adult gait

An investigation into the relationship between rocker sole designs and alteration to lower limb kinetics, kinematics and muscle function during adult gait

In summation, the research contained in this thesis is therefore aimed at systematically understanding the precise effects of altering parameters associated with different footwear rocker sole profiles on lower limb kinematics and kinetics, linked to muscle biomechanics and alterations to muscle activity in the lower limbs (especially for the calf group of muscles and anterior leg muscles). It was thought important for the purposes of this thesis to primarily examine the effect of such interventions on healthy subjects’ gait. This is because it would afford the opportunity to judge the results more precisely without other factors which may have an effect on the gait and muscle changes at the ankle and knee if subjects were to have varying amounts of disability. In addition, it would be necessary to perform gait laboratory testing on subjects who would be able to walk at similar speeds to negate the effects of walking speed on the comparative effects of altering the soles and heels of shoes. The intention was therefore to understand the precise effect of five different footwear design features (rocker sole apex position, rocker sole relative stiffness level, the type of heel shape, the rocker apex angle and alteration to heel height) on gastrocnemius medial head, soleus, tibialis anterior, rectus femoris and biceps femoris muscle activity and specific MTU parameters, plus temporal-spatial parameters during walking in adult healthy subjects. The results were intended to inform and make recommendations as to which footwear sole and heel unit design features would be suitable to alleviate symptoms associated with IC during rehabilitation protocols and also give indications for suitable intervention for various other pathologies.

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Study on the large-displacement behaviour of a spiral spring with variations of cross-section,  orthotropy and prestress

Study on the large-displacement behaviour of a spiral spring with variations of cross-section, orthotropy and prestress

The investigated concept consists of an initially planar spiral- shaped elastic body. The outer end of the spiral is fixed to ground. The inner end of the spiral is rigidly connected to a point that in undeformed configuration coincides with the origin (hereinafter endpoint ), see Fig. 1. This point is treated as the end-effector throughout the remainder of the chap- ter. The spiral is defined in the yz-plane, (hereinafter main plane). In this concept it is interesting to analyze the effect of the global displacement of the endpoint on the local load- mode at cross-sectional level. If the endpoint of the spiral is loaded in the main plane the prevalent load-mode of the cross-section is bending. If the endpoint is loaded out of the plane instead, the prevalent load-mode of the cross-section is torsion. In this study we analyze the effect of altering the torsion stiffness in relation to the bending stiffness and its effect on the global behavior of the spiral. The torsional stiff- ness is altered through variations in the cross-section shape, orthotropic material orientation and prestress. It is expected that by lowering the torsional stiffness at the cross-section level, the global stiffness out-of-plane is reduced as well. Particular attention is given to the behavior at large displace- ments which is not obvious.

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Optimization of vibration reduction by De Coupling method in power train 
		of trucks

Optimization of vibration reduction by De Coupling method in power train of trucks

 Perform an Eigen value analysis (SOL 103) next. Compute only a few modes first, verify their frequencies, and view their mode shapes for reasonableness. If the researcher graphical postprocessor can animate the mode shapes, do so because that helps the researcher to visualize them. Things to check at this step are local mode shapes, in which one or a few grid points are moving a very large amount relative to the rest of the model (this can indicate poor stiffness modeling in that region), and unwanted rigid-body modes (which can arise due to improper specification of the boundary conditions or a mechanism).Once the researcher are satisfied with these results, perform the full eigen value analysis (for as many modes as you need).

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Greenfield tunnelling in sands: the effects of soil density and relative depth

Greenfield tunnelling in sands: the effects of soil density and relative depth

0·9. Wong & Kaiser (1991) identified a tunnelling-induced mode of behaviour for cohesionless soils (for at-rest stress ratios lower than unity) that is initiated by localised soil yielding at the tunnel shoulders and develops, for further stress relief withinthe tunnel, with either (i) ear-shaped shear bands intercepting the ground surface or (ii) yielding of the roof (i.e. soil above the tunnel crown). These two yielding mechanisms match well to the shear strain distributions measured in the centrifuge tests for loose and dense sands, respectively. However, Wong & Kaiser (1991) did not relate these mechanisms to the soil relative density.

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Ultrafine particles cause cytoskeletal dysfunctions in macrophages: role of intracellular calcium

Ultrafine particles cause cytoskeletal dysfunctions in macrophages: role of intracellular calcium

microtubuli, results in an accelerated relaxation and in a moderately increased stiffness. Figure 2A illustrates the retardation of relaxation caused by 100 µ g/ml P90, and the modulation by Verapamil and BAPTA-AM together with the retardation produced by 4 µ M Cytochalasin D. In comparison to the effects induced by the cytoskeletal drugs the dysfunctions produced by the carbonaceous UFP suggests destructions of microfilamentous structures and hence dysfunctions of the cytoskeleton. This is also in agreement with other studies which showed impairment of the phagocytic capacity (an actin based mechanism) after incubation with different types of UFP [19,20]. Intracellular calcium plays a central role in the modula- tion of the defense mechanisms causing inflammation. Further studies have shown that ufCB causes a transient increase of intracellular calcium, which can be inhibited by the calcium channel blocker Verapamil [13,60]. This was reflected in this study by the inhibition of ufCB induced cytoskeletal dysfunctions in the presence of Vera- pamil. Interestingly, the intracellular calcium chelator BAPTA-AM did not induce the expected suppression of cytoskeletal dysfunction. The reason for this lack of effect is not clear but suggests that not only the level of intracel- lular calcium is responsible for the ufCB induced dysfunctions.

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A cantilever approach to estimate bending stiffness of buildings affected by tunnelling

A cantilever approach to estimate bending stiffness of buildings affected by tunnelling

The evaluation of the effect of tunnel construction on buildings is a problem being faced by engineers around the world. Building bending stiffness is an important parameter in tunnel-soil-structure interaction analyses. The con- struction of a new tunnel influences an existing building via induced ground movements, and the existence of a building also affects ground displacements due to tunnelling via its stiffness and weight. The magnitude of the effect de- pends on the properties of the building and foundation as well as the complex soil-structure interactions that occur. In this paper, an approach is proposed in which the building response to tunnelling is related to the bending of a cantilever beam and empirical-type relationships are developed to predict building bending stiffness. This approach is relevant to cases where the build- ing is perpendicular to the tunnel axis and its nearest edge does not overlap more than half of the tunnel cross-section. Rigorous finite element analy- ses are used to evaluate the response of buildings to ground displacements and expressions are provided which relate three-dimensional building bend-

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Comparative Study of Rigorous Analysis and Superposition Principle for Floating Granular Piles Group

Comparative Study of Rigorous Analysis and Superposition Principle for Floating Granular Piles Group

Since 1969 with pioneer study of [2]in the area of granular piles as ground improvement technique, number of researchers has worked in this area, giving new heights to this area. [3] studied two types of column i.e. plain and reinforced (encased) and propose an upper bound analysis of the settlement of the foundation system with stone column inclusions, considering the non-linear behavior of the surrounding soft clay. [4] conducted the finite element method (FEM) studies to study the effect of encasing stone columns with geo-synthetic material for improvement in the load carrying capacity of the stone columns. The stone columns and the soft soils were modeled using hyperbolic non-linear elastic models, while the geo-synthetic encasement around the stone column was modeled as a linear elastic material.Acceleration of consolidation rate by stone columns was analyzed by, [5] within the framework of a basic unit cell i.e., a cylindrical soil body around a column. [6] presented the, analytical solutions based on the unit- cell concept to predict deformation behaviors of geo-textile-encased stone columns at any depth below the top plane of the columns. [7] studied that for a given reinforcement condition, the percentage improvement in load-carrying capacity was found to be higher for un-drained conditions than for drained conditions. The variation in the magnitude of the percentage improvement in strength with area replacement ratio indicated that, for drained conditions, there could be an upper bound area replacement ratio beyond which the benefits of increasing the area ratio become economically unjustifiable. [8] investigates the effects of encasement stiffness and strength on the response of individual geo-textile encased granular columns embedded in soft soil through model tests. Similarity analysis was first executed to determine the suitable properties of the constituents used in the model tests to ensure that the prototype-scale and model-scale geo-textile encased granular columns exhibit comparable behavior.

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Strength recovery of remolded dredged marine clay: thixotropic hardening vs  induced cementation

Strength recovery of remolded dredged marine clay: thixotropic hardening vs induced cementation

Referring to Fig. 3, the deflection points (approximate intersection of the relatively linear sections of each plot) are joined with a dashed line to illustrate the time lapse between marked deformation caused by the cone drop and the subsequent plateau. While the deflection points could not always be readily distinguished (e.g. in Fig. 3b), the connecting plots emerged to be discernible. It can be noted that the rest period required for effective stiffness gain of the cement-treated samples was more subtle than the original samples.

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On Generating Expected Kinetostatic Nonlinear Stiffness Characteristics by the Kinematic Limb-Singularity of a Crank-Slider Linkage with Springs

On Generating Expected Kinetostatic Nonlinear Stiffness Characteristics by the Kinematic Limb-Singularity of a Crank-Slider Linkage with Springs

Figure  3 shows the motion of the mechanism which works around the right limiting position which is also one of the two kinematic limb-singularity positions. The mechanism moves from the initial non-singular position with no deflected springs (Figure  3(a)), passes the kin- ematic limb-singularity position (Figure  3(b)) and then arrives at the end non-singular position (Figure  3(c)). During the motion as Figure  3 shows, the potential energy of the spring placed at joint C increases from zero to the maximum and then falls to zero. Thus if the stiffness of the torsional springs are not too large, the potential energy of the mechanism may have one local maximum and two local minimums, which correspond to the unstable position (θ b as shown in Figure  3) and two

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Comparing the relative volume with the relative inradius and the relative width

Comparing the relative volume with the relative inradius and the relative width

Recently some results have been obtained by comparing the relative perimeter and the minimum relative diameter (the minimum between the diameter of E and the diameter of its complement) for subdivisions of planar convex sets (see [2]), and the relative volume with the maximal and the minimal relative diameters (see [1]).

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Advanced Structural Modelling and Design of Wind Turbine Electrical Generators

Advanced Structural Modelling and Design of Wind Turbine Electrical Generators

equations tend to overestimate the overall stiffness by giving too much weight to the stiffness of the discs. Considering the applicability and reliability of this method for sub structures, it is thought that better outcomes could be achieved if a more detailed research on the calculation of the stiffness of complete structures is carried out. Rotor and stator disc structures were tested under different modes of deflection in order to identify which one is the most dangerous and how it would affect the structures. As the data revealed, the stiffness drops with each deflection mode showing its lowest value at Mode 4 in both cases. By taking into account this important feature, the design can be tuned so that the structures can withstand this deflection mode in the most reliable, lightweight and cost effective manner. On the other hand, if the designer is interested in varying the most damaging deflection mode (due to different requirements), it can be done by altering the thicknesses of the sub structures. This is a trade-off process in which the stiffness of the overall structure can be increased for some deflection modes at expense of the others. Finally, with the optimum disc structure fully described, a further optimisation was carried out using finite element tools. The ANSYS Shape Optimisation© add-on was utilised to identify the areas not contributing to carry the loads. The Design Explorer ANSYS tool was linked to a CAD model in SolidWorks which was produced by looking at the data retrieved from the shape optimisation add-on so that the dimensions of the areas to be removed could be maximised in order to diminish the overall structural mass. Two models were studied. One at a small scale which showed a 15 % reduction in mass whether compared with a solid disc structure capable of supporting the same loading conditions and one at a large scale which gave a drop of 38 % if compared to the disc structure model obtained in Section 4.3.4.

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A self-adjusting stiffness center design for large stroke compliant XY nanomanipulators

A self-adjusting stiffness center design for large stroke compliant XY nanomanipulators

In this subsection, the simulation of the parasitic rotation is conducted. As a result, the parasitic rotation of the redun- dant constraint is < 1 µrad, which demonstrates the perfor- mance of the proposed SASC-based design. And the para- sitic rotation of the decoupling mechanism is below 40 µrad. One possible reason is mainly due to the relatively low rota- tional stiffness. The parasitic rotation of the proposed stage is shown in Fig. 15, where the parasitic rotation is < 8 µrad. The maximum parasitic rotation occurs when the motion stage reaches to its middle stroke, and this result agrees with the shape of the moment variation.

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Stiffness modeling of parallel mechanisms at limb and joint/link levels

Stiffness modeling of parallel mechanisms at limb and joint/link levels

By combining screw theory with the virtual joint method, this paper introduces a general and systematic approach for stiffness modelling of parallel mechanisms under ‘unloaded equilibrium’ conditions. The following conclusions are drawn. (1) We have proposed a hierarchical structure of the stiffness model of parallel mechanisms that essentially consists of two stiffness maps: (a) the map between stiffness matrices in the Cartesian space and in the joint space at limb level, which has the nature of a system comprising a set of parallel connected spring elements; (b) the map between stiffness matrices in the joint space at limb level and at element level, which has the nature of a set of serially connected springs. Merging these two threads results in a general, explicit expression for the Cartesian stiffness matrix in terms of the compliance matrices of all joints/links evaluated in their local body-fixed frames, the wrench systems imposed upon the limbs, and the twist systems generated by the virtual joints.

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CT Elastography: A Pilot Study via a New Endoscopic Tactile Sensor

CT Elastography: A Pilot Study via a New Endoscopic Tactile Sensor

form for strength of materials and is the materials fixed number for the material with the isotropy. In other words, as for expressing hardness of biological tissue comprised of complicated materials as a Young’s modulus, there is unreasonableness basically. Based upon the foregoing, each researcher wrote the hardness of the living body soft tissue using each measuring equipment originally con- ventionally and has been reported for a relative value. After 2000, as Natural SI Unit, it was suggested we stan- dardized the hardness of the living body soft tissue using kPa and displayed it and to weigh it. Our definition and measurement of the elasticity follow those of R. M. Hoch- much et al. [20]. In other words, we define the hardness of the biological soft tissue which we should relatively compare as an absolutely needed quantity. Even this study and this article adopt this suggestion.

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