کرنسی بنانے کا اختیار اور موجودہ کرنسی کی شرعی و فقہی حیثیت اور فقہا کی آرا

Who has the authority of making money in Islamic Law? What is the value of current currency? What is the historical back ground of present paper currency? In this article all these issues are taken up and analyzed in the light of opinions of various schools of  hought. 

Experimental and Numerical Assessment of Confined and Unreinforced Brick Masonry Structures

Brick masonry is widely used for building construction throughout the world. However, unreinforced brick masonry buildings performed poorly in the 2005 Kashmir earthquake, in Pakistan, resulting in a decline in the use of masonry construction. To investigate and quantify the performance of masonry against the seismic forces by confining it through typical stiffer, line elements (column and beams), a full-scaled room model of an area 3048 × 3658mm (10 × 12 ft) and height of 3353mm (11 ft) was constructed using confined brick masonry and tested under quasi-static cyclic loading. Damage details were observed after each loading cycle. The structure’s response was interpreted through a hysteresis curve, after which the envelop curves were drawn and the envelop curve was then converted into bilinear curve for determining different limit states and performance levels. A comparison of the results has been made with four different studies done on the similar model made of unreinforced brick masonry (URM) before and after retrofitting and concrete block masonry (CBM) before and after retrofitting previously tested at the same testing facility. In addition to experimental testing, the numerical analysis, principally elaborated by the finite element (FE) method, is ineludible for brittle materials like masonry. A new modeling methodology was proposed for numerical analysis of full-scale confined brick masonry structures. Two modeling strategies were used within a single structure, where the in-plane walls were modeled using “simplified micro-modeling” approach and out-of-plane walls were modeled using “macro-modeling” approach. The lateral load capacity is associated with the in-plane shear resistance of masonry elements, therefore more detailed analysis is required for in-plane walls to achieve a comprehensive understanding of the damage mechanism and load transfer. The investigation of the in-plane response of confined masonry (CM) structures is significant. Additionally, the proposed hybrid model was validated by comparing the results of experimental studies of confined brick masonry structure. A parametric study was conducted to examine the consequence of brick and mortar properties on the global structural performance metrics (e.g., base shear coefficient, effective stiffness, response modification factor, and the three (03) performance levels (i.e., Collapse Prevention, Life Safety and Immediate Occupancy limits)). It was noticed that these performance metrics, vary considerably by varying the properties of materials. Apart from that, the damage behavior and damage pattern were also assessed for the stronger comprehension of consequence of these parameters on the response of the structure. The hybrid-modeling approach gives enough accuracy in predicting the lateral load behavior as well as the damage mechanism of confined brick masonry structure, subjected to lateral loading. Performance-based seismic assessment has significantly developed in the last 20 years. Even with our best efforts to enhance the quantitative methods and tools to characterize uncertainties, seismic hazard, damages and losses, elemental behavior, nonlinear responses– the fact is that an accurate prophecy of building performance during an earthquake is still very challenging for practitioners and researchers alike. Therefore, substantial havoc to building infrastructure has been noticed in major earthquakes in Pakistan and it is required to have better understanding of their seismic vulnerability. As an element of this study to evaluate seismic risk in Abbottabad city (situated in the North of KPK province of Pakistan), a database was compiled previously in terms of characteristics such as number of stories, age of building and type of construction. This study investigates a significant number of these structures deemed to be a characteristic example of the Pakistan building infrastructure. No such study has been found in the literature so far on the vulnerability study of Pakistan building infrastructure with and without retrofitting, using performance based seismic assessment methodology, and this study will serve as guide for researchers in Pakistan to conduct further research in this area. To measure their potential vulnerability, the instigated damage due to augmented shaking force needs to be determined. This description of the structure vulnerability, in conjunction with the potential hazard, gives well informed, risk-based assessment that can be made by response metrics like collapse prevention and economic effects. Numerical analysis was performed using available database, accumulated through field survey to represent precisely, the actual behavior of the building infrastructure. Two sets of building fragility curves, before retrofitting and after retrofitting, are employed to simulate the seismic performance of the building infrastructure in all the cases. To calculate the losses, an inventory composed of both the structural and non-structural components was composed using field survey database obtained previously. This study is performed in a efficient manner to obviously illustrate the different aspects necessary to execute more advanced seismic risk assessment studies.