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This paper aims to propose an efficient method to conduct the preliminary analyses of medium or high-rise wall-frame structural systems with vertically varying properties. To this end, a finite element is formulated to take the shear deformation of the shear wall and the constrained moment of the link beam.

The differential equation of the structure is derived from the total potential energy. Its homogenous solutions are functions of initial parameters (deflections and inner forces). To solve the structure with vertically non-uniform properties, the authors first use the classical Timoshenko beam element and then heuristically propose a finite element that uses the initial parameter solutions as shape functions and is easier to implement. A post-processing method to compute the shear force in the frame and shear wall is developed. Modal analysis using the consistent mass matrix is also incorporated. Numerical examples demonstrate the accuracy and mesh independency of the proposed element.

The shear deformation of the shear wall and the constrained moment of the link beam significantly influence the static response of the structure. Taking into account the shear deformation can eliminate the misleading result of zero-base shear force of the frame and give much better predictions of the system natural frequencies.

The proposed method achieves higher accuracy than the classical approach most often used. The finite element formulation derived from transformations of the initial parameter solutions is simple and has superior numerical performance. The post-processing method allows for a fast determination of the shear force distributions in the shear wall and frame.

In this work, the authors aim to employ the so-called linked-interpolation concept already tested on beam and quadrilateral plate finite elements in the design of displacement-based higher-order triangular plate finite elements and test their performance.

Starting from the analogy between the Timoshenko beam theory and the Mindlin plate theory, a family of triangular linked-interpolation plate finite elements of arbitrary order are designed. The elements are tested on the standard set of examples.

The derived elements pass the standard patch tests and also the higher-order patch tests of an order directly related to the order of the element. The lowest-order member of the family of developed elements still suffers from shear locking for very coarse meshes, but the higher-order elements turn out to be successful when compared to the elements from literature for the problems with the same total number of the degrees of freedom.

The elements designed perform well for a number of standard benchmark tests, but the well-known Morley's skewed plate example turns out to be rather demanding, i.e. the proposed design principle cannot compete with the mixed-type approach for this test. Work is under way to improve the proposed displacement-based elements by adding a number of internal bubble functions in the displacement and rotation fields, specifically chosen to satisfy the basic patch test and enable a softer response in the bench-mark test examples.

A new family of displacement-based higher-order triangular Mindlin plate finite elements has been derived. The higher-order elements perform very well, whereas the lowest-order element requires improvement.

In this study, the application of a novel combined steel curved damper (SCD) and steel plate shear wall (SPSW) system in the 5-, 10- and 15-storey steel moment-resisting frames (SMR) subjected to earthquake excitation has been investigated. The proposed system is called here as the SMR-WD (steel moment resisting–wall damper).

At the beginning of this research, an SMR-W and an SMR-D are separately modeled in ABAQUS software and verified against the available experimental data. After that, three different heights SMR-WD systems (5-, 10- and 15-storey) are designed and simulated. Then, their performances are examined and compared to the corresponding SMR-W under the effects of six actual earthquake records.

The obtained results show that the proposed system increases the mean values of the base shear for 5-, 10- and 15-storey SMR-WD equal to 27, 20.15 and 16.51%, respectively compared to the corresponding SMR-W. Moreover, this system reduces the drift of the floors so that the reduction in the average values of maximum drift for 5-, 10- and 15-storey SMR-WD is equal to 10, 7 and 29%, respectively with respect to the corresponding SMR-W. The results also reveal that the considered system dissipates more energy than SMR-W so that the increase in the mean values of the energy absorption for 5-, 10- and 15-storey SMR-WD is 30.8, 25.6 and 41.3%, respectively when compared to the SMR-W. Furthermore, it is observed that SMR-WD has a positive effect on the seismic performance of the link beams and panel zones of the frames. By increasing the height of the structure in the SMR-WD, the energy dissipation and base shear force increases and the drift of floors decreases. Hereupon, the proposed SMR-WD system is more useful for tall buildings than SMR-W frames.

For the first time, the application of a novel combined steel curved damper (SCD) and steel plate shear wall (SPSW) system in the 5-, 10- and 15-storey steel moment-resisting frames (SMR) subjected to earthquake excitation has been investigated.

Beginners and even experienced ones have difficulties in completing the structural fire analysis due to numerical difficulties such as convergence errors and singularity and have to spend a lot of time making many repetitive changes on the model. The aim of this article is to highlight the advantages of explicit solver which can eliminate the mentioned difficulties in finite element analysis containing highly nonlinear contacts, clearance between modeled parts at the beginning and large deflections because of high temperature. This article provides important information, especially for researchers and engineers who are new to structural fire analysis.

The finite element method is utilized to achieve mentioned purposes. First, a comparative study is conducted between implicit and explicit solvers by using Abaqus. Then, a validation process is carried out to illustrate the explicit process by using sequentially coupled heat transfer and structural analysis.

Explicit analysis offers an easier solution than implicit analysis for modeling multi-bolted connections under high temperatures. An optimum mesh density for bolted connections is presented to reflect the realistic structural behavior. Presented explicit process with the offered mesh density is used in the validation of an experimental study on multi-bolted splice connection under ISO 834 standard fire curve. A good agreement is achieved.

What makes the study valuable is that the points to be considered in the structural fire analysis are examined and it is a guide that future researchers can benefit from. This is especially true for modeling and analysis of multi-bolted connections in finite element software under high temperatures. The article can help to shorten and even eliminate the iterative debugging phases, which is a problematic and very time-consuming process for many researchers.

THE REQUIREMENT was for a retractable undercarriage with a steerable nose wheel to be certified through CAA to the BCAR and FAR Part 25 Regulations.

The study aims to explore factors affecting stilt construction and the possibilities of using innovative materials and construction methods to re-establish the traditional stilt structures.

The study employs a qualitative research method using an in-depth interview with selected architects to document experience and insights of the architects on the challenges and possibilities of using innovative materials and construction methods to re-establish the traditional stilt structures. Purposive sampling was used to determine the respondents for the study. Architects with experience designing stilt houses in architects' architectural practice were selected to take in the study.

Study revealed that generally architects are keen on using stilt structures. Building materials and costs associated with designing and constructing stilt structures were identified as the key challenges. However, architects suggest using recycled building materials as possible solutions to encourage the construction of stilt structures in Malaysia. The architects also preferred to use hybridized recycled materials for stilt structures as hybridized materials have improved structural properties and functions. Additionally, the study identified “psychological hesitation” or “accessibility” as a factor affecting the construction of stilt buildings.

Throughout this study, some limitations have been dealt with. The first is the limitation of sample size. Contemporary stilt architecture is not very common in Malaysia today, and not many architects have experience in designing stilt houses. Although the method of purposive sampling was used, a larger sample size could have generated a more diverse result. The second limitation is the dearth of research on contemporary stilt houses in Malaysia. As stilt construction is uncommon in Malaysia and the existing material focuses primarily on traditional Malay houses, this has been one of the major challenges. Finally, most of the literature on stilt construction is from Southeast Asia, limited or insufficient studies and literature on local stilt construction would have a greater benefit to the study.

The outcomes from this study would benefit the scholars who have an interest in exploring stilts construction in contemporary architecture as well as innovative construction materials and construction methods. As the study brings forth the challenges and possibilities of restoring the traditional stilt constructions, the study can be used as a reference by designers to garner a deeper understanding of the traditional stilt construction and encourage designers to focus on possible innovations for stilt construction from the aspects of materials and methods in ensuring the traditional element is present in future design and construction.

The study is a response to an obvious dearth body of knowledge in stilt construction in the Malaysian context. The study identifies the key challenges and possible and practical solutions. The findings of this study represent a scholastic effort that can be used as a reference by academics and scholars.

Reinforced concrete (R.C.) beams are part of the structure so their design depends on the structural code and its requirements. In this paper, two simply supported R.C. beams were designed in terms of flexural and shear strength design requirements and investigated in terms of deflections and crack widths, when subjected to two asymmetric concentrated loadings, where one load is double the other one. Both beams had dimensions of 3,500 mm length, 200 mm width, and 300 mm height. The first beam (beam B1) was designed according to the combination of the structural requirements of American and Saudi building codes (ACI318-and-SBC304), while the second beam (beam B2) was designed according to the structural requirements of Eurocode (EC2). The paper aims to discuss these issues.

The design of ultimate capacity (section capacity) to design both flexure and shear capacity according to the design provisions in EC2 code deals with the Ultimate Limit State Design Approach, while it deals with the Ultimate Strength Design Approach according to the design provisions in both ACI318 and SBC304 codes. In the serviceability (mid-span deflection and flexural crack width) check, the three codes deal with the Serviceability Limit State Design Approach.

The laboratory behaviour of both test beams was as expected in flexure and failed in shear, but there was more shear cracks in the left shear span for both beams. This refers to the left applied loading and the spacing of shear links, where the failure occurred at the higher loading points. Perhaps, if the number of links was increased in the left side of the beam during the manufacture and reinforcing of the beam, the failure loading will be delayed and the diagonal cracks will be decreased.

From this study, it was concluded that: the ACI318 and SBC304 design approaches are safer than the EC2 design approach. The EC2 design approach is more economic than the ACI318 and SBC304 design approaches. The structural behaviour of both test beams was as expected in flexure but both beams failed in shear. The shear failure was in the left side of both test beams which was referred to a high loading point. Diagonal cracks followed the applied loading until both beams reached to the failure.

The Euler beam theory is used to study the dynamic stability of a composite material slider‐crank mechanism with an elastic connecting rod. The Ritz finite element procedure is applied to derive the governing equations of motion of the mechanism. Based on the assumption that the slider‐crank mechanism is subjected to a sinusoidal input torque and the operation condition is at a steady dynamic state, the governing equations represent a system of second order differential equations with periodic coefficients of the Mathieu‐Hill type. Making use of the Bolotin method, the boundaries between stable and unstable solutions of the elastic connecting rod are constructed. The advantages of using composite materials in the design of mechanisms are demonstrated.

The purpose of this study is to establish a relationship between causes and effects, the respect of materials characteristics values [concrete compressive strength (f_c) and steel yield stress (f_y)] and the norms of the construction dispositions value (covers). This study is motivated by the post-seismic damages related to the plastification of the reinforced concrete (RC)/beams sections, named plastic hinges. The results are given by fragility curves representing the failure probability (P_f) of the plastic hinges versus covers value.

A mechanical-reliability coupling methodology is proposed and performed on three frames (three, six and nine storey). For each frame, seven covers the value of reinforcement steel bars has been taken into account in the beams. After definition of the limit state function G(x), a process of idea to twin-track; deterministic and probabilistic, is considered. Thus, numerical simulations are carried out under ETABS© software, to extract a soliciting moments M_s(x). Then, ultimate moments M_u(x), the result of reliability approach are calculated using Monte Carlo Simulations. In this step, two random variables; concrete compressive strength in 28 days of age (f_c) and steel yield stress (f_y), have been studied.

In the mechanical study, the results show that, the first plastic hinge appears at the beams for all frames. In the reliability study, the (f_y) variation shows that all plastic hinges are in failure domain, nevertheless, the (f_c) variation leads to have all sections in the safety domain, except A7 and B7 models. The failure probability (P_f) calculation according to (f_c) and (f_y) shows that an absolute error of 0.5 cm in the steel bars covers can switch the frame from the safety domain to the failure domain.

The plastic hinges reliability of the RC/ frame structures is independent on the high of the structure. The (f_c) random variable according to the used distribution law does not affect the reliability (safety or failure). However, the impact of the steel yield stress variation (f_y) is not negligible. The errors in covers affect considerably the strength of the elements.