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Necessity for adaption of high-rise reinforced concrete structures' design and practical steps of implementation through nonlinear staged analysis by consideration of long-termAttention to adaption of structural design with practical implementation steps by applying priority and posteriority of construction schedule into the structural design in form of sequential construction analysis has always been strongly recommended by researchers and scholars in recent years. Basically, all floors of the structure are simultaneously subjected to dead and live loads in conventional structural analyses. While the dead loads of the structural elements and floors are gradually applied to the previously constructed members during the progress of construction which depends on method of construction and its executive arrangements [1] On the other hand, it is obvious that the dead load of newly added elements during construction is carried by the same part of the structure which has been constructed up until that point. Thus, distribution of stresses and displacements caused by the load of existing parts at any stages is independent of size, properties and the presence of other elements which have not entered the construction process [2]. Examples of individuals who studied about above subjects are Choi and Kim (1985) who introduced sequential construction with the concept of active floor in structural analysis [3]. The principles of active floor's analysis are based on three concepts of active floor, inactive floor and deactivated Floors with a reverse order of actual process of construction which is from top to bottom and performing analysis as much as the number of floors in the structure. Use of substructuring technique can be helpful in reduction of number and volume of calculations [4,5]. In this method, floor by floor activation process can be done for a group of floors which will increase computing speed and will reduce the time and computational efforts. Choi, Chung, Lee and Wilson presented a simple method to simulate the actual behavior of structure based on practical construction steps in 1992 named Correction Factor Method (CFM) and considered the effects of sequential construction in structural analysis [6]. The mentioned method is able to modify the results of conventional one-step structural analyses only using correction factors and without the need for accurate and time-consuming staged analysis and it is able

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Summary Temperature is one of the most important factors affecting the long‐term behavior of concrete: Its remarkable impact is directly involved in the analysis and design of structures. In this paper, the effect of ambient temperature on the development of modulus of elasticity, creep, and the shrinkage of concrete with time is investigated under nonlinear staged analysis. This is performed under two sections of constant temperature changes with four different temperatures as indicators of the spectrum from cold to tropical cities, and the seasonal changes in ambient conditions with real growth of creep curves and modulus of elasticity in four modes of the construction start at each of the four seasons of the year, giving indications of the long‐term behavior of high‐rise dual systems and special moment resisting frames. The structures are designed optimally, based on the results of the conventional one‐step analysis and regardless of inelastic strains and temperature effects. This ensures that after applying the concrete time‐dependent parameters at desired temperatures and redesigning according to new forces of nonlinear staged analysis, the feasibility of comparing changes in sections and drifts of the structures can be established. The results show that summer is the worst season to start construction.

Nowadays, the use of steel plate shear walls, as an effective seismic resisting system, has been of great interest in enhancing the lateral strength and stiffness of buildings both in renovation and seismic rehabilitation of existing concrete and steel structures. In the present research, the shear strength and stiffness of steel plate shear walls in various configurations of stiffeners, including horizontal, vertical, and horizontal-vertical, were investigated by finite element method and finally semi-empirical relations were presented in this regard. The results indicated that the shear strength and stiffness of stiffened SPSWs were well predicted by the proposed relations, but increasing the number of stiffeners above a certain range will not have a significant effect on enhancing the stiffness and strength.