Test Procedures for Advanced Characterization of Bituminous Binders Employed for Pavement Construction in Public Works Authority Road Projects - State of Qatar

This paper illustrates the approach adopted by the Public Works Authority (Ashghal) of the State of Qatar for the advanced chemical and rheological characterization of bituminous binders (both neat and modified). The ultimate objective of testing is to create a database of employed binders, which may be meaningful for the optimization of the selection of materials and for the consequent enhancement of pavement performance. This paper provides an illustration of employed testing procedure and briefly discusses typical experimental results

Use of Crumb Rubber Modified Binders and Asphalt Mixtures in Public Works Authority Road Projects - State of Qatar

This paper illustrates the approach adopted by the Public Works Authority (Ashghal) of the State of Qatar for the widespread implementation in road projects of paving technologies related to the use of crumb rubber modified binders (CRMBs). Such an approach has entailed the monitoring of a full-scale preliminary trial, the definition of a prequalification system for crumb rubber and CRMB producers, and the development of mix design and quality control guidelines applicable to CRMB asphalt mixtures. Experimental results obtained in the preparatory phases of work and during the approval process of materials and mixtures are critically presented

Engineering models for the design of long-lasting, sustainable, cost-efficient and climate-responsive pavements for Ashghal road projects in the State of Qatar

The planning, design, construction and management of modern transportation infrastructures is based on the use of continuously updated methodologies that consider, among others, the concept of sustainability. In such a context, for the specific case of road pavements, it is of crucial importance to carry out quantitative analyses based on the use of optimized engineering models. These models explicitly consider environment-pavement interactions, environmental impacts generated by all the components involved in the supply chain, and financial flows associated to pavement construction and maintenance. Such an approach is being adopted by the Public Works Authority (Ashghal) of the State of Qatar, that is developing and implementing models tailored for its infrastructure projects and local environmental conditions. This paper provides an overview of some of the employed models and methodologies that are based on the physics of pavement structures and on the assessment of environmental and economic indicators. It is shown that such an approach leads to significant improvements to current practice and to the enhanced use of recycled materials, while still guaranteeing required pavement performance

Irrational use of antibiotics with representation of antimicrobial resistance patterns in Sudan: a narrative review

Increasing bacterial resistance to antibiotics is a growing menace, mainly caused by the rapid genetic modification of bacterial strains and new alternations in behavior favoring their survival. There is no doubt that the irrational use of antibiotics is one of the factors contributing to the rise of this problem, whether that be in hospitals or at a community level. Although the extent of this influence is yet to be learned, it is definite that this is of great impact on the endemic disease patterns in developing areas specifically and on an expanding global issue generally