Search results

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.

The purpose of this paper is the analysis of the dissipation of pore water pressures in the core of an earth dam, under the effect of water level fluctuations in the reservoir under operating conditions, taking into account the partial emptying and filling.

The Taksebt Dam, Tizi-Ouzou, Algeria was chosen as a case study, using a two-dimensional transient finite element numerical model. The GeoStudio calculation software is used through the SEEP/W. The latter takes into account the flow in the saturated and unsaturated zone, the formulation of SEEP/W allows the analysis of the dissipation of pore water pressures in the dyke. Starting from the maximum level of the reservoir, at least one cycle of partial emptying-filling was modelled over an eight-year operating period from 2011 to 2019. The input variables were the water level variation curve, material properties and boundary conditions.

It can be concluded that the numerical results obtained from the simulation model on the different points studied, namely, the pore water pressures are satisfactory as long as they are close to those recorded in the field by the pore pressure cells with an average error not exceeding 10% except for some measurements where the error is 20%. When the water level in the reservoir varies, the pore water pressures vary and their behaviour follows these fluctuations. Some points in the dam are affected by negative pore water pressures. No abnormal situations have been detected pore water pressures.

The numerical results of the simulation are analysed and validated against actual pore pressure cell measurements under operating conditions.

This research aims to investigate whether the uncertainty of gaining legitimacy from organizational change is an important antecedent of resistance to change and to explore why some enterprises are reluctant to choose institutional entrepreneurship for transformation when the uncertainty of gaining legitimacy from organizational change is high.

The hypotheses are tested by multiple regression analysis and structural equation model, using data collected from a big company with 14 subsidiaries undergoing organizational change.

Uncertainty of gaining legitimacy from organizational change not only results in resistance to change through the mediating variable – organizational readiness for change but also is an important influencing factor for enterprises’ choices of change strategy.

Transformational change may alter original organizational legitimacy so that some enterprises prefer isomorphic change and decoupling change to maintain original organizational legitimacy, rather than institutional entrepreneurship to seek new organizational legitimacy.

To foster innovation and a new form of creation for firms, governments should provide enterprises with legitimacy in time by establishing a rapid legitimacy learning mechanism to supplement institutional voids, whereas enterprises should promote organizational readiness for change to reduce the negative influence of the uncertainty of gaining legitimacy.

This research reveals that the uncertainty of gaining legitimacy from organizational change is an antecedent of resistance to change and enriches antecedent categorical presupposition of resistance to change. These findings provide valuable insight for explaining why enterprises in economic entities with institutional voids such as China chose similar change strategies rather than institutional entrepreneurship.