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The purpose of this paper is to investigate the effect of pick density, pile height and pile yarn count (both single- and double-ply yarn) on the colour fastness to crocking, colour fastness to washing, colour fastness to water of woven velour printed terry fabrics. These variables have also been optimized for developing high-quality fabrics.

Variables were selected on the basis of past research experience and samples were prepared according to the Box–Behnken design of experiments. The samples were tested for colour fastness to crocking, colour fastness to washing and colour fastness to water by following AATCC 8, AATCC 61, 2A and AATCC 107, respectively.

The colour fastness to crocking, washing and water of woven velour printed terry fabrics increases with the decrease in pile height and pick density. The colour fastness properties of the fabric increase with increase in fineness of the pile yarn count. Woven velour printed terry fabric with 16.25 picks per cm, 3.5 mm pile height and 16 Ne pile yarn will show best colour fastness. Woven velour printed terry fabric (plied pile yarn) with 16.25 picks per cm, 3.5 mm pile height and 2/24 Ne pile yarn will show best colour fastness

Proved a practical approach to control fastness properties of the fabric by changing fabric variables.

Colour fastness properties of woven velour printed terry fabrics have never been reported. The research work gives the better understanding to develop high quality of fabrics by reducing pile height and pick density. This will also reduce the cost of the fabric.

Catastrophe theory can directly deal with discontinuity without any connection with the special inner mechanism, which makes it suitable for system research, whose inner action is unknown but outer one can be observed. There are many inner factors, which affect the bearing capacity of pile, it is different to ascertain bearing capacity of pile. The purpose of this paper is to present a new calculation method of bearing capacity of pile by the catastrophe theory.

The cusp model of catastrophe theory and its expression are discussed in this paper. By means of mechanical model analysis, bearing capacity of pile is systematically studied coupling catastrophe steady mechanism with equilibrium conditions of single pile. The settlement of top pile is transformed into the normal form of cusp catastrophe. The relationship between the settlement of top pile and vertical bearing capability of pile is built.

Vertical bearing capacity of single pile was deduced by means of energy principle and catastrophe theory based on settlement of critical instability of pile.

Accessibility and availability of the constitutive equation of concrete of pile and parameter are the main limitations which model will be applied.

A very useful reference for design processes engineers.

The estimated results of the example correspond to one of practical experience, which provides a basis for design of vertical bearing capacity of single pile.

The purpose of this paper is the dynamic analysis and seismic damage assessment of steel sheet pile quay wall with inelastic behavior underground motions using several accelerograms.

Finite element analysis is conducted using the Plaxis 2D software to generate the numerical model of quay wall. The extension of berth 25 at the port of Bejaia, located in northeastern Algeria, represents a case study. Incremental dynamic analyses are carried out to examine variation of the main response parameters under seismic excitations with increasing Peak ground acceleration (PGA) levels. Two global damage indices based on the safety factor and bending moment are introduced to assess the relationship between PGA and the damage levels.

The results obtained indicate that the sheet pile quay wall can safely withstand seismic loads up to PGAs of 0.35 g and that above 0.45 g, care should be taken with the risk of reaching the ultimate moment capacity of the steel sheet pile. However, for PGAs greater than 0.5 g, it was clearly demonstrated that the excessive deformations with material are likely to occur in the soil layers and in the structural elements.

The main contribution of the present work is a new double seismic damage index for a steel sheet pile supported quay wharf. The numerical modeling is first validated in the static case. Then, the results obtained by performing several incremental dynamic analyses are exploited to evaluate the degradation of the soil safety factor and the seismic capacity of the pile sheet wall. Computed values of the proposed damage indices of the considered quay wharf are a practical helping tool for decision-making regarding the seismic safety of the structure.

To solve the instability problem of Zhangjiayao landslide caused by rainfall, the internal mechanism of slope instability and the supporting effect of anti-slide piles are studied. The research results can provide theoretical basis for the prevention and control of loess landslides.

A three-dimensional finite element model of Zhangjiayao landslide is established by field geological survey, laboratory test and numerical simulation.

The results show that Zhangjiayao landslide is a loess-mudstone contact surface landslide, and rainfall leads to slope instability and traction landslide. The greater the rainfall intensity, the faster the pore water pressure of the slope increases and the faster the matrix suction decreases. The longer the rainfall duration, the greater the pore water pressure of the slope and the smaller the matrix suction. Anti-slide pile treatment can significantly improve slope stability. The slope safety factor increases with the increase of embedded depth of anti-slide pile and decreases with the increase of pile spacing.

Based on the unsaturated soil seepage theory and finite element strength reduction method, the failure mechanism of Zhangjiayao landslide was revealed, and the anti-slide pile structure was optimized and designed based on the pile-soil interaction principle. The research results can provide theoretical basis for the treatment of loess landslides.

1. A three-dimensional finite element model of Zhangjiayao landslide is established.

2. Zhangjiayao landslide is a loess-mudstone contact surface landslide.

3. The toe of Zhangjiayao slope is first damaged by heavy rainfall, resulting in traction landslide.

4. The deformation of Zhangjiayao slope is highly dependent on rainfall intensity and duration.

5. The anti-slide pile can effectively control the continuous sliding of Zhangjiayao slope.

A three-dimensional finite element model of Zhangjiayao landslide is established.

Zhangjiayao landslide is a loess-mudstone contact surface landslide.

The toe of Zhangjiayao slope is first damaged by heavy rainfall, resulting in traction landslide.

The deformation of Zhangjiayao slope is highly dependent on rainfall intensity and duration.

The anti-slide pile can effectively control the continuous sliding of Zhangjiayao slope.

The dynamic response of the nuclear power plants (NPPs) with pile foundation reinforcement have not yet been systemically investigated in detail. Thus, there is an urgent need to improve evaluation methods for nonlithological foundation reinforcements, as this issue is bound to become an unavoidable task.

A nonlinear seismic wave input method is adopted to consider both a nonlinear viscoelastic artificial boundary and the nonlinear properties of the overburden layer soil. Subsequently, the effects of certain vital parameters on the structural response are analyzed.

A suitable range for the size of the overburden foundation is suggested. Then, when piles are used to reinforce the overburden foundation, the peak frequencies in the floor response spectra (FRS) in the horizontal direction becomes higher (38%). Finally, the Poisson ratio of the foundation soil has a significant influence on the FRS peak frequency in the vertical direction (reduce 35%–48%).

The quantifiable results are performed to demonstrate the seismic responses with respect to key design parameters, including foundational dimensions, the Poisson Ratio of the soil and the depth of the foundation. The results can help guide the development of seismic safety requirements for NPPs.

This paper aims to investigate the responses of single piles and pile groups due to tunneling-induced ground movements in a two-layered soil system. The analyses mainly focus on the additional single pile responses in terms of bending moment, lateral deflection, axial force, shaft resistance and pile settlement. Subsequently, a series of parametric studies were carried out to better understand the responses of single piles induced by tunneling. To give further understanding regarding the pile groups, a 2 × 2 pile group with two different pile head conditions, namely, free and capped, was considered.

Using the PLAXIS three-dimensional (3D) software, a full 3D numerical modeling is performed to investigate the effects of ground movements caused by tunneling on adjacent pile foundations. The numerical model was validated using centrifuge test data found in the literature. The relevance of the 3D model is also judged by comparison with the 2D plane strain model using the PLAXIS 2D code.

The numerical test results reveal that tunneling induces significant displacements and internal forces in nearby piles. The magnitude and distribution of internal forces depend mainly on the position of the pile toe relative to the tunnel depth and the distance between the pile and the vertical axis of the tunnel. As the volume loss increases from 1% to 3%, the apparent loss of pile capacity increases from 11% to 20%. By increasing the pile length from 0.5 to 1.5 times, the tunnel depth, the maximum pile settlement and lateral deflection decrease by about 63% and 18%, respectively. On the other hand, the maximum bending moment and axial load increase by about 7 and 13 times, respectively. When the pile is located at a distance of 2.5 times the tunnel diameter (Dt), the additional pile responses become insignificant. It was found that an increase in tunnel depth from 1.5Dt to 2.5Dt (with a pile length of 3Dt) increases the maximum lateral deflection by about 420%. Regarding the interaction between tunneling and group of piles, a positive group effect was observed with a significant reduction of the internal forces in rear piles. The maximum bending moment of the front piles was found to be higher than that of the rear piles by about 47%.

Soil is a complex material that shows differently in primary loading, unloading and reloading with stress-dependent stiffness. This general behavior was not possibly being accounted for in simple elastic perfectly plastic Mohr–Coulomb model which is often used to predict the behavior of soils. Thus, in the present study, the more advanced hardening soil model with small-strain stiffness (HSsmall) is used to model the non-linear stress–strain soil behavior. Moreover, unlike previous studies THAT are usually based on the assumption that the soil is homogeneous and using numerical methods by decoupled loadings under plane strain conditions; in this study, the pile responses have been exhaustively investigated in a two-layered soil system using a fully coupled 3D numerical analysis that takes into account the real interactions between tunneling and pile foundations. The paper presents a distinctive set of findings and insights that provide valuable guidance for the design and construction of shield tunnels passing through pile foundations.

Build-operate-transfer (BOT) contracts are widely used in the construction and operation of charging piles for new energy vehicles worldwide and stipulate that governments grant charging pile operators franchises for a certain period of time to invest in the construction and operation of the charging piles. The charging piles are then transferred to governments when the concession expires. To encourage charging pile operators to build and operate charging piles, governments usually provide two kinds of subsidies, namely construction and operating subsidies.

The authors establish a typical game model to study the optimal BOT contract between a government and a charging pile operator and their preferences for the two kinds of subsidies.

First, the authors show that there are substitution and complementarity effects between the concession period and the subsidy level. Second, the operator prefers the construction subsidy (operating subsidy) when the additional operating cost is low (high). The government prefers the operating subsidy (construction subsidy) when consumer sensitivity to the number of charging piles is low (high) and the concession period is short or long (moderate). Finally, the adjusted joint subsidy can not only improve social welfare but also that the charging pile operator can obtain the same profit as under the operating subsidy at a lower subsidy amount.

This work develops the first analytical model to study two subsidies in the construction and operation of charging piles and investigate the optimal BOT contract and subsidy preferences. The insights are compelling not only for the charging pile operator but also for policymakers in practice from a circular economy perspective.

This paper aims to investigate single pile and pile group responses due to deep braced excavation-induced soil movement in soft clay overlying dense sand. The analysis focuses first on the response of vertical single pile in terms of induced bending moment, lateral deflection, induced axial force, skin resistance distribution and pile settlement. To better understand the single pile behaviour, a parametric study was carried out. To provide further insights about the response of pile group system, different pile group configurations were considered.

Using the explicit finite element code PLAXIS 3 D, a full three-dimensional numerical analysis is carried out to investigate pile responses when performing an adjacent deep braced excavation. The numerical model was validated based on the results of a centrifuge test. The relevance of the 3 D model is also judged by comparison with the 2 D plane strain model using the PLAXIS 2 D code.

The results obtained allowed a thorough understanding of the pile response and the soil–pile–structure interactions phenomenon. The findings reveal that the deep excavation may cause appreciable bending moments, lateral deflections and axial forces in nearby piles. The parametric study showed that the pile responses are strongly influenced by the excavation depth, relative pile location, sand density, excavation support system and pile length. It also showed that the response of a pile within a group depends on its location in relation to the other piles of the pile group, its distance from the retaining wall and the number of piles in the group.

Unlike previous studies which investigated the problem in homogeneous geological context (sand or clay), in this paper, the pile response was thoroughly studied in a multi-layered soil using 3 D numerical simulation. To take into account the small-strain nonlinear behaviour of the soil, the Hardening soil model with small-strain stiffness was used in this analysis. For a preliminary design, this numerical study can serve as a practical basis for similar projects.

The purpose of this paper is to establish the optimization model of designs for sparse distributed pile foundation based on multi‐goals fuzzy optimization theory, to promote the application of the optimization model into project.

In the designing of sparse distributed pile foundation, there are many feasible design schemes, the selection of designs is a decision making of multi‐goals and factors. Owing to uncertain and imprecise environment in which the designing of sparse distributed pile foundation exists, the theories of fuzzy optimization are chosen as mathematical framework to optimize the design schemes.

Since relative optimal degree is used to judge, the optional result of using fuzzy optimization theories in sparse pile foundation design selection is more rational according to a site project.

The availability of data and precision of index weight selection are the main limitations as to which model will be applied.

A very useful optimal method for the sparse pile foundation design selection.

The new approach of optimal selection for sparse pile foundation design due to fuzzy optimization theories.

The purpose of this paper is to provide a cost-effective foundation technique for the design of foundations of transmission towers, heavily loaded structures, etc.

Experimental model tests are conducted in a model test tank to find out the effect of length and diameter of geogrid encased granular pile anchors, the relative density of sand and the angle of inclination of the pile from the vertical on uplift behavior of granular pile anchors.

The uplift capacity of the geogrid encased granular pile anchor increased with increasing length and diameter of granular pile anchor. Further, increasing the relative density of surrounding soil increased uplift capacity of geogrid encased granular pile anchor system. Moreover, increasing the angle of inclination of loading also increased uplift capacity of whole system. Thus, the proposed system can be effectively used in field for further applications.

The paper is helpful for the engineers looking for cost-effective foundation techniques for heavily loaded structures.