Graphics statics is a geometric method for analyzing and calculating the internal forces of structural members under external loads. In this method, two diagrams of structural form and internal forces in the members are determined and drawn graphically. The process of parameterization of this method in both form production and internal force calculations can lead to various designs with the least amount of time. In such circumstances, Architects and Civil engineers can make the best choice based on the criteria and objectives of the structure, form and geometric topology. In this paper, the parametric graphics statics analysis of various truss designs, derived from the popular species Warren, Pratt, Howe, and Fink, or any related free-form, is performed in the Python programming language in the grasshopper Plugin. The results of the analysis performed with the results in the available sources show that the proposed parametric graphics statics method has a high performance in calculating the internal forces of members of conventional trusses or free-form with any desired load.

linear static analysis is one of the most widely used methods proposed by the codes for the seismic analysis of structures. Several methods have been presented for determining the static lateral load pattern. In spite of the simplicity of these procedures, their accuracy, especially for structures in which the influences of higher modes are significant, is not desirable. In this study, a new method is developed to improve the lateral load pattern in linear static analysis. To achieve the proposed lateral load distribution, firstly, the average responses of some structures subjected to some earthquakes are acquired. Then, regarding the dynamic responses of the structures, the static lateral load pattern compatible with the average responses is developed. Eventually, to derive a straightforward and hands-on lateral load distribution, using a statistical study, some relations coupled with a graph are developed. Since the proposed method is developed based on the structural responses resulting from linear dynamic analysis (time-history analysis), it is shown that the suggested way, despite its simplicity and efficiency, presents appropriate accuracy in predicting the responses of the structures subjected to seismic excitations. The developed lateral load is applied for three frames with 5, 10 and 14 stories. The inter-story drifts of these frames are achieved under 14 earthquake excitations. After that, the proposed lateral loads of code 2800 and FEMA 356 are used on these frames and the responses are derived. The outcomes show that whereas the average error of the proposed lateral load for these frames is around 7, 5 and 7%, the average errors of code 2800 and FEMA 356 are almost 20, 10 and 25%. Comparing the inter-story drifts for the developed lateral load pattern with the dynamic results, validates its performance. The developed method is evaluated for a set of structures with different fundamental periods. Results show that the method gives higher accuracy in comparison with the static method of Iranian standard 2800 and FEMA 356. Also, the developed procedure can be considered as an appropriate technique for determining lateral load distribution in seismic codes.

In this paper a modal pushover procedure is presented in which distribution of lateral forces is calculated using the story shears. The shear force of each story is determined using its relative interstory displacement and stiffness in each mode of vibration utilizing spectral analysis relations. To retain simplicity of the procedure, like the common pushover procedures, the initial elastic dynamic characteristics of buildings are used for spectral analysis throughout. A combination rule for modal story shears is proposed that keeps the signs of responses. Therefore, the computed lateral loads contain effects of the desired number of modes and the nonlinear static analysis is performed in a single stage accounting for effects of higher modes. The lateral displacements, story shears and cumulative plastic hinge rotations are compared with the results of the conventional and modal pushover analysis and with the result of the exact nonlinear dynamic analysis. The comparative study establishes good accuracy of the proposed method as an alternative modal pushover procedure.

In the nanoscale, the continuity assumption may be violated, and hence, the classical theories, which have been introduced based on the continuity assumption, may lose their accuracy. Therefore, new size-dependent continuum theories are demanded for proper design and analysis of micro/nano-electro-mechanical systems. The aim of the present study is to develop a new non-linear theoretical model, based on the Modified couple stress theory, for analysis of static and dynamic pull-in instabilities of nanobeams, utilized in nano switches. In the present model, the size effect parameter, the fringing field effect, the electro static forces, the intermolecular forces (Casimir and Van der Walls) are taken into account. The non-linear Euler-Bernoulli governing equation of the beam motion and the corresponding boundary conditions are derived by using Hamilton’ s principle. The results show that the decrease in the size of the beam increases the beam stiffness. An increase in the fringing field effect, the size effect parameter or decrease in intermolecular forces as well as decrease in the substrate length would increase the ultimate pull-in voltage. Also, when a cantilever nanobeam is affected partially from the free-side end, the effect on the increase of the pull-in parameters of the intermolecular forces and the voltage is greater than that of the nanobeam is affected partially from its support side.

Introduction: Cerebral Palsy (CP) refers to a class of non-progressive neurological disorders that permanently affect individuals' sensory-motor abilities and typically appear in infancy or early childhood. The present study aimed to investigate the effect of linear and nonlinear training methods on the static balance ability of children with hemiplegic CP. Methods: A total of 20 boys with hemiplegic CP, aged 7-12 years, were selected through convenience sampling and they were assigned into experimental and control groups. The Sharpened Romberg test was used to measure static balance scores. The linear and nonlinear training groups performed specific exercises for four weeks, three days a week, and one hour per session for each method. Multivariate Analysis of Covariance (MANCOVA) and univariate Analysis of Covariance (ANCOVA) were conducted at a significance level of P≤0. 05. Findings: The results showed a significant difference between the linear and nonlinear training methods in at least one of the static balance variables (p=0. 001). Additionally, considering the higher scores of the nonlinear group, this training method resulted in better static balance scores (with eyes open and closed) compared to the linear method in children with hemiplegic CP. Conclusion: Overall, the findings of this study emphasize the importance of the nonlinear training method in improving the static balance of children with hemiplegic CP and support the constraint-led approach

The objective of this review to be submitted in two independent parts, for steel frames and for RC frames, is to compare their structural performance with respect to the proposed N2-method, and so also of the consequent convenience of using pushover methodology for the seismic analysis of these structures. A preliminary investigation is presented on a pushover analysis used for the seismic performance of metallic braced frames equipped with diagonal X-bracing and K-bracing systems. Three steel frames are analysed corresponding to 3, 6 and 10 floor regular buildings that were modelled in the MIDAS/Civil finite element software. To obtain the pushover curve a nonlinear static methodology is used. For the RC frames three commercial programs (SAP 2000, Seismo Struck and MIDAS/Civil) are used in order to perform a parametric study based on pushover analyses. The equivalent strut method is applied to simulate the influence of the masonry infill panels; to evaluate the influence of these on the capacity curves, several strut width values are considered.The parametric study also addresses the influence of other parameters on the structural behaviour and non-linear capacity curves of the RC frame, namely: length and position of the plastic hinges and different loading patterns (uniform, modal and triangular distributions).

The objective of this review to be submitted in two independent parts, for steel frames and for RC frames, is to compare their structural performance with respect to the proposed N2-method, and so also of the consequent convenience of using pushover methodology for the seismic analysis of these structures. A preliminary investigation is presented on a pushover analysis used for the seismic performance of metallic braced frames equipped with diagonal X-bracing and K-bracing systems. Three steel frames are analysed corresponding to 3, 6 and 10 floor regular buildings that were modelled in the MIDAS/Civil finite element software. To obtain the pushover curve a non-linear static methodology is used. For the RC frames three commercial programs (SAP 2000, SeismoStruck and MIDAS/Civil) are used in order to perform a parametric study based on pushover analyses. The equivalent strut method is applied to simulate the influence of the masonry infill panels; to evaluate the influence of these on the capacity curves, several strut width values are considered. The parametric study also addresses the influence of other parameters on the structural behaviour and non-linear capacity curves of the RC frame, namely: length and position of the plastic hinges and different loading patterns (uniform, modal and triangular distributions).

Progressive collapse studies generally assess the performance of the structure under gravity and blast loads, while earthquakes may also lead to the progressive collapse of a damaged structure. In this study, the progressive collapse response of concentrically braced dual systems with steel moment-resisting frames was assessed under seismic loads through pushover analysis using triangular and uniform lateral load patterns. Two different bracing types (X and inverted V braces) were considered, and their performances were compared under different lateral load patterns using the nonlinear static alternate path method recommended in the Unified Facilities Criteria (UFC) guideline. Eventually, the seismic progressive collapse resistance of models was compared to their progressive collapse response under gravity loads. These studies showed that models under the seismic progressive collapse loads satisfied UFC acceptance criteria and limited rehabilitation objective. The structures had better performance under seismic progressive collapse than models under gravity loads because of more resistance, ductility, suitable load redistribution, and more structural elements that participated in load redistribution. Furthermore, despite studies on progressive collapse under gravity loads, the dual system with X braces showed better progressive collapse performance (more resistance, residual reserve strength ratio and ductility) under seismic loads than the model with inverted V braces.

Background and Aim: The aim of the present study was to investigate the effect of the Hand Static Rest Splint on reducing the pain and other compliance of Rheumatoid Arthritis (RA). Materials and Methods: In the present clinical trial, 12 patients, aged 35-50 (average: 39 years) with RA, referring to the Occupational Therapy Unit of Taleghani hospital and meeting America College of Rheumatology diagnostic criteria, were included. Visual Analogue Scale (VAS) was administered and swelling, tenderness and morning stiffness were assessed. Moreover, assessments of active range of motion using goniometry and grip strength with Jamar dynamometer in both hands were performed. Statistical analysis of data was performed using t-test and Mann-Whitney Test for two independent samples and willcoxon tests and paired t-test for paired samples run in SPSS, version 18. The level of significance was set at p˂ 0. 05. Results: The findings showed that the Static Rest Splint led to improvement in the wrist range of motion (flexion p=0/005, extension p=0/03) when the two groups were compared, but it did not have a significant effect on Morning Stiffness (p=1), pain (p=0/1), Swelling (p=0/06), and Tenderness (p=0/2). However, when compared between after and before intervention in hand with splint, pain (p=0/02) and wrist range of motion (p=0/004) improved. Conclusion: Based on the findings of the current study, and since using splints only improve range of motion in the wrist compared between two groups and pain relief before and after the intervention, it seems that using hand Static Rest Splint to reduce other symptoms need further investigation and also given that the use of this position without stress on the tendon can be effective in reducing the causes deformity, further studies are needed to more delineate these points.