سر ہرمان دیبر
سر ہرمان دیبر، جنھوں نے ۹۷ سال کی عمر میں وفات پائی ہے اور جن کے قواے جسمانی و دماغی آخر وقت تک پوری تندرستی کی حالت میں رہے، ان کی کتاب ’’طویل العمری‘‘ سے متعلق حال میں دوبارہ شایع ہوئی ہے، طویل العمری کے مختلف نسخے مختلف اشخاص نے تجویز کیے، لیکن سر ہرمان دیبر کے نزدیک اس کا راز صرف تین چیزوں میں شامل ہے، اولاً جسمانی محنت و ورزش، یعنی انسان کاہل نہ ہو، بلکہ تازہ ہوا میں کافی طور پر چلتا پھرتا رہے، دوسرے یہ کہ اپنی طبیعت کو قانع رکھے، قناعت کا لازمی نتیجہ یہ ہوگا کہ فکر و مایوسی اس کے پاس نہ آئے گی اور طبیعت بشاش رہے گی، تیسری اور سب سے اہم شرط یہ ہے کہ کھانے پینے میں بے اعتدالی نہ کرے، بلکہ ہمیشہ اعتدال ملحوظ رکھے، شرائط بالا کی پابندی کے ساتھ مصنف مرحوم کا دعویٰ ہے کہ ہر شخص انہی کی سی عمر و صحت حاصل کرسکتا ہے۔ (اپریل ۱۹۲۰ء)
COVID-19 pandemic is a global health crisis with 61, 149,391 confirmed cases and 370,478 deaths till 29May, 2020 [1]. This pandemic has shattered many economies with an estimated loss of $5.8 trillion to $8.8 trillion globally. This economic loss can result in reduction in funds to World Health Organization. Unfortunately, United States of America (USA) has announced termination of any further funding to WHO which can lead to another global health crisis[2]. As WHO is a voluntary funding based organization its main donor are America, China, Japan, Germany and United Kingdom. Among these USA is the main donor with a contribution of $115.8million alone followed by China $57.4 million, Japan $41million, Germany $29.1 million and UK $21.9 million [3]. America’s termination of funding can put WHO and child health programs in serious crisis. Among many programs run by WHO one of the most important program is immunization of children. Immunization coverage programs save 2-3 million livesper year causing decline in measles related deaths, eradication of polio, surveillance of rotavirus, BCG and DTaP vaccination in children[4]. It is estimated that during MillenniumDevelopment Goal (MDG) there is overall decline in child related mortalities due to malaria, measles, diarrhea, AIDS and meningitis [5]. Remarkable results are achieved with measles are diarrhea immunization programs causing a decline in death rate by 73% and 80% respectively. According to a study with current success rate diarrhea related deaths can be virtually eliminated by 2030. Another successful program is “End Polio” program which eradicated polio from world except from Pakistan and Afghanistan [4][6]. This termination of funds to WHO can waste all previous efforts in developing countries. On the other hand despite of all efforts still 19.4 million children did not received prescribed dose of vaccines. Data analysis revealed among these 60% of children belong to 10 developing countries namelyAngola, Brazil, the Democratic Republic of the Congo, Ethiopia, India, Indonesia, Nigeria, Pakistan, the Philippines and Viet Nam [4]. These countries mainly rely on foreign funding and Non-Government Organization (NGOs) for child health care programs.
Response modification factors in building codes are an essential part of all seismic building codes. These factors are used in the denominator of the base shear equation in the simplified method of seismic design to reduce the base shear in order to encompass non-linear seismic resistance potential of buildings. The selection of response modification factor for a specific class of structural system has, therefore, serious implications on the safety and economy of structural designs. Keeping in view the importance of response modification factor, a large number of researchers around the world, have made attempts to evaluate this factor for different types of structural systems. In all the cases, however, these factor have been evaluated considering a particular design code and local construction practices. Therefore, these factors are not universal and hence cannot be used in every region. Response modification factors that are part of building code of Pakistan have been adopted from an American code. Variation and uncertainties in construction practices and quality of construction in Pakistan are different from those in the US which renders the response modification factors inapplicable to design of buildings in Pakistan, until verified. There is a need for development of response modification factors for forthcoming edition of building code of Pakistan that are reflective of the true seismic building performance in Pakistan. This research was carried out to compute response modification factors for Special Moment Resisting Frame (henceforth referred to as SMRF) buildings in Pakistan This research work was initiated through a building stock survey that was conducted in five main cities of Pakistan to study contemporary construction practices. Several disparities were found to exist between design specifications and construction practices. These included reduced compressive strength of concrete as compared to specified xi compressive strength, haphazard and increased spacing of ties and stirrups, improper location of lap splices and smaller diameter of reinforcement as compared to nominal diameter, amongst others. Experimental models of RC beam-column connections were built incorporating these deficiencies. These models were then subjected to reverse cyclic loading in quasi-static experiments. The experimental results obtained from quasi-static tests were used to calibrate numerical models of the connections and were consequently integrated into numerical building models. Numerical simulations were carried out on reinforced concrete frames to compute response modification factors. Response modification factor was computed for a total of 256 twodimensional hypothetical reinforced concrete buildings based on experimental response of beam-column connections. The set of hypothetical frames considered varying span lengths and number of storys. The frames were designed based on BCP-SP 07 and analyzed using non-linear pushover analysis for computation of response modification factor. The disparity between design specifications and actual construction was accounted for in non-linear constitutive law for structural members derived from the experimental work. The computed response modification factors showed a wide dispersion with building span lengths, number of storys and detailing deficiencies. As a general trend, the values of response modification factors decreased with increasing period of vibration of the buildings and increasing span lengths. Based on the extensive experimental and numerical work, response modification factor value of 8.5 is recommended for RC SMRFs for standard quality control environments, where a full compliance between design specifications and construction practices is ensured. The overall range of the computed response modification factors for fullycode- compliant SMRF buildings is from 6.0 to 12.0 which signifies a large scatter in the values based on varying span lengths and building heights. This necessitates the use of period-dependent response xii modification factors in the forthcoming editions of the Building Code of Pakistan. For buildings with construction deficiencies pertaining to concrete quality and reinforcement detailing, the values of response modification factors range from 4.0 to 6.1 for buildings with varying span lengths and height. The determination of quality control environment and subsequent use of response modification factor is left to the discretion of design engineers. It is, however, emphasized that a judicious selection of response modification factor, based on ground realities, should be made by design engineers to avoid a compromise on the safety and economy of structural designs. A minimum requirement of 20.db should be adopted in the building code for proportioning the column depth in exterior beam-column connections to ensure hinging in beams rather than joints.