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CONTENTS
Volume 23, Number 6, December 2022
 


Abstract
In recent decades, infrastructural development has exploded, particularly in the coastal region of Saudi Arabia. The rising demand of most consumed aggregate in construction can be effectively compensated by the alternative material like scoria which lavishly exists in the western region. Scoria is characterized as lightweight aggregate beneficially used to develop lightweight concrete (LWC) - a potential alternative of normal weight concrete (NWC) ensuring reduction in the structural element's size, increase in building height, comparatively lighter foundation, etc. Hence, the goal of this study is to incorporate scoria-based structural lightweight concrete and evaluate its impact on superstructure and foundation design beside contributing to the economy of construction. Fresh, mechanical, and rheological properties of the novel LWC have been investigated. The structural analyses employ the NWC as well as LWC based structures under seismic and wind loadings. The commercial finite element package - ETABS was employed to find out the change in structural responses and foundations. The cost estimation and SWOT analysis for superstructure and foundation have also been carried out. It was revealed that the developed LWC enabled a more flexible structural design. Notable reduction in the steel and concrete prices of LWC might be possible in the low-rise building. It is postulated that the cost-effective and eco-friendly LWC will promote the usage of scoria as an effective alternative in Saudi Arabia and GCC countries for structurally viable LWC construction.

Key Words
eco-friendly; economic construction; flat slab; lightweight concrete; scoria; sustainable structure; SWOT analysis

Address
Department of Civil and Construction Engineering, College of Engineering, Imam Abdulrahman Bin Faisal University, 31451, Dammam, Saudi Arabia

Abstract
Global or partial damage to a structure due to the failure of gravity or lateral load-bearing elements is called progressive collapse. In the present study, the alternate load path (ALP) method introduced by GSA and UFC 4-023-03 guidelines is used to evaluate the progressive collapse in special steel moment-resisting frame (SMRF) buildings. It was assumed that the progressive collapse is due to the earthquake force and its effects after the removal of the elements still remain on the structures. Therefore, nonlinear dynamic time history analysis employing 7 earthquake records is used to investigate this phenomenon. Internal and external column removal scenarios are investigated and the stiffness of the connections is changed from semi-rigid to rigid. The results of the analysis performed in the OpenSees program show that the loss of the bearing capacity of an exterior column due to a seismic event and the occurrence of progressive collapse can increase the inter-story drift of the structure with semi-rigid connections by more than 50% and make the structure unable to satisfy the life safety performance level. Furthermore, connection stiffness severely affects the redistribution of forces and moments in the adjacent elements of the removed column.

Key Words
alternate load path; connection stiffness; moment-resisting frame; nonlinear dynamic analysis; progressive collapse

Address
Department of Civil Engineering, Ayatollah Amoli Branch, Islamic Azad University, Amol, Iran

Abstract
Previous studies have shown that pile-soil interactions have significant influences on the isolation efficiency of an isolated structure. However, most of the existing tests were carried out using a 1-g shaking table, which cannot reproduce the soil stresses resulting in distortion of the simulated pile-soil interactions. In this study, a centrifuge shaking table modelling of the seismic responses of a friction pendulum bearing isolated structure with a pile foundation under earthquakes were conducted. The pile foundation structure was designed and constructed with a scale factor of 1:100. Two layers of the foundation soil, i.e., the bottom layer was made of plaster and the upper layer was normal soil, were carefully prepared to meet the similitude requirement. Seismic responses, including strains, displacement, acceleration, and soil pressure were collected. The settlement of the soil, sliding of the isolator, dynamic amplification factor and bending moment of the piles were analysed to reveal the influence of the soil structure interaction on the seismic performance of the structure. It is found that the soil rotates significantly under earthquake motions and the peak rotation is about 0.021 degree under 24.0 g motions. The isolator cannot return to the initial position after the tests because of the unrecoverable deformation of the soil and the friction between the curved surface of the slider and the concave plate.

Key Words
base isolation; centrifuge shaking table test; earthquake; pile-soil interaction; pile foundation structure

Address
Shu-Sheng Qu: Tianjin Research Institute for Water Transport Engineering, Ministry of Transport of the People's Republic of China, Tianjin 300000, China
Yu Chen: School of Transportation Science and Engineering, Civil Aviation University of China, Tianjin 300300, China
Yang Lv: Tianjin Key Laboratory of Civil Structure Protection and Reinforcement, Tianjin Chengjian University, Tianjin 300384, China

Abstract
EDCC (Eco-Friendly Ductile Cementitious Composites) is a recently created class of engineered cementitious composites that exhibit extremely high ductility and elastoplastic behavior under pure tension. EDCC contains reduced amounts of cement and very large volumes of fly ash. Due to these properties, EDCC has become one of the solutions to use in seismic upgrading. This paper discloses previous studies and research that discussed the seismic upgrading of unreinforced, non-grouted, unconfined, and non-load bearing masonry walls which are called URM infill walls using the EDCC technique. URM infill wall is one of the weak links in the building structure to withstand the earthquake waves, as the brittle behavior of the URM infill walls behaves poorly during seismic events. The purpose of this study is to fill a knowledge gap about the theoretical and experimental ways to use the EDCC in URM infill walls. The findings reflect the ability of the EDCC to change the behavior from brittle to ductile to a certain percentage behavior, increasing the overall drift before collapse as it increases the energy dissipation, and resists significant shaking under extensive levels with various types and intensities.

Key Words
ductility; eco-friendly ductile cementitious composite; fiber reinforced concrete; seismic upgrading; sprayable; URM infill walls

Address
Haider Ali Abbas: The Iraqi Ministry of Agriculture, Baghdad, Iraq
Naida Ademović: Faculty of Civil Engineering, University of Sarajevo, Sarajevo, Bosnia and Herzegovina
Husain K. Jarallah: Department of Civil Engineering, College of Engineering, Mustansiriyah University, Baghdad, Iraq

Abstract
Handball sport, as its name postulates, is a team sport which highly physical workout. During a handball play, several ball impacts are applied on the hands resulting vibration in the forearm, upper arm, shoulders and in general in whole body. Hand has important role in the handball's game. So, understanding about the dynamics and some issues that improve the stability of the hand is important in the sport engineering field. Ulna and radius are two parallel bones in lower arm of human hand which their ends are located in elbow and wrist joint. The type of the joint provides the capability of rotation of the lower arm. These two bones with their ends conditions in the joints constructs a 4-link frame. The ulna is slightly thinner than radius. So, understanding about hand kinematics in handball's game is an important thing in the engineering field. So, in the current work with the aid of a multi-physics simulation, dynamic stability analysis of the ulna and radius bones will be presented in detail.

Key Words
dynamic stability; hand kinematics; handball's game; mathematical modeling; multi-physics simulation

Address
Kun Qian: College of Sports Science, Shenyang Normal University, Shenyang 110034, Liaoning, China
Sanaa Al-Kikani: Department of Physical Education and Sport Science, Al-Mustaqbal University College, 51001 Hillah, Babylon, Iraq
H. Elhosiny Ali: Research Center for Advanced Materials Science (RCAMS), King Khalid University, Abha 61413, Saudi Arabia
Department of Physics, King Khalid University, Abha 61413, Saudi Arabia
Physics Department, Faculty of Science, Zagazig University, 44519 Zagazig, Egypt

Abstract
This paper assesses the influences of modeling assumptions and uncertainties on the performance of the non-linear finite element (FE) model updating procedure and model clustering method. The results of a shaking table test on a four-story steel moment-resisting frame are employed for both calibrations and clustering of the FE models. In the first part, simple to detailed non-linear FE models of the test frame is calibrated to minimize the difference between the various data features of the models and the structure. To investigate the effect of the specified data feature, four of which include the acceleration, displacement, hysteretic energy, and instantaneous features of responses, have been considered. In the last part of the work, a model-based clustering approach to group models of a four-story frame with similar behavior is introduced to detect abnormal ones. The approach is a composition of property derivation, outlier removal based on k-Nearest neighbors, and a K-means clustering approach using specified data features. The clustering results showed correlations among similar models. Moreover, it also helped to detect the best strategy for modeling different structural components.

Key Words
EDP; hysteretic models; kmeans clustering; modeling uncertainty; nonlinear finite element model updating; OpenSees; panel zone

Address
Mehrdad Ebrahimi, Reza Karami Mohammadi and Elnaz Nobahar: Department of Civil Engineering, K.N. Toosi University of Technology, Tehran, Iran
Ehsan Noroozinejad Farsangi: Faculty of Civil and Surveying Engineering, Graduate University of Advanced Technology, Kerman, Iran


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