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Tall buildings have unique seismic challenges, particularly the P-delta effect. This can cause an increase in loads on certain parts of the structure, leading to potential instability or collapse. The solution is to use buckling restrained bracing (BRB) systems, which improve the lateral strength of the structure and control the P-delta effect. The present study aimed to determine the effectiveness of various brace configurations in reducing the seismic response of a 50-story reinforced concrete structure, with a focus on P-delta effects. To achieve this, linear dynamic analysis (response spectrum analysis) was conducted using E-TAB software. The selection of bracing configuration, however, depends upon the seismic zone. For this reason, five distinct configurations (X-pattern, inverted V, forward inclined, zig-zag, and bare frame) are considered for the analysis of buildings in different seismic zones. A building model was employed to study the behaviour of a structure with and without BRB to compare the parameters of storey drift, story displacement, diaphragm drift, story shear, story stiffness, and story acceleration using E-TAB software. Results showed that both Type-4 and Type-2 braces perform similarly in several aspects in seismic zones III and V. However, Type-2 braces perform slightly better in terms of storey stiffness-Y, with a lower difference of 39-40 % compared to Type-4 braces with a difference of 49 %.

Abstract Background Tuberculosis (TB) in children is frequently paucibacillary and non-severe forms of pulmonary TB are common. Evidence for tuberculosis treatment in children is largely extrapolated from adult studies. Trials in adults with smear-negative tuberculosis suggest that treatment can be effectively shortened from 6 to 4 months. New paediatric, fixed-dose combination anti-tuberculosis treatments have recently been introduced in many countries, making the implementation of World Health Organisation (WHO)-revised dosing recommendations feasible. The safety and efficacy of these higher drug doses has not been systematically assessed in large studies in children, and the pharmacokinetics across children representing the range of weights and ages should be confirmed. Methods/design SHINE is a multicentre, open-label, parallel-group, non-inferiority, randomised controlled, two-arm trial comparing a 4-month vs the standard 6-month regimen using revised WHO paediatric anti-tuberculosis drug doses. We aim to recruit 1200 African and Indian children aged below 16 years with non-severe TB, with or without HIV infection. The primary efficacy and safety endpoints are TB disease-free survival 72 weeks post randomisation and grade 3 or 4 adverse events. Nested pharmacokinetic studies will evaluate anti-tuberculosis drug concentrations, providing model-based predictions for optimal dosing, and measure antiretroviral exposures in order to describe the drug-drug interactions in a subset of HIV-infected children. Socioeconomic analyses will evaluate the cost-effectiveness of the intervention and social science studies will further explore the acceptability and palatability of these new paediatric drug formulations. Discussion Although recent trials of TB treatment-shortening in adults with sputum-positivity have not been successful, the question has never been addressed in children, who have mainly paucibacillary, non-severe smear-negative disease. SHINE should inform whether treatment-shortening of drug-susceptible TB in children, regardless of HIV status, is efficacious and safe. The trial will also fill existing gaps in knowledge on dosing and acceptability of new anti-tuberculosis formulations and commonly used HIV drugs in settings with a high burden of TB. A positive result from this trial could simplify and shorten treatment, improve adherence and be cost-saving for many children with TB. Recruitment to the SHINE trial begun in July 2016; results are expected in 2020. Trial registration International Standard Randomised Controlled Trials Number: ISRCTN63579542, 14 October 2014. Pan African Clinical Trials Registry Number: PACTR201505001141379, 14 May 2015. Clinical Trial Registry-India, registration number: CTRI/2017/07/009119, 27 July 2017.