Thesis (M.Sc)-Cairo University, 2025.

Bibliography: pages 96-97.

Post-tensioning is a prestressed concrete technology widely used in various
construction, maintenance, and restoration applications. It employs prestressing steel,
which has about four times the tensile strength of reinforcing steel. The system is highly
efficient as it balances and counteracts compressive and tensile stresses from loads by
utilizing the full cross-section of the concrete element. Additionally, it can adjust the
placement of reinforcement to better withstand these stresses. Post-tensioning can be
applied in numerous structures, including multipurpose facilities, parking garages,
commercial and residential buildings, bridges and storage structures. One of the most
famous post-tensioned floor systems is two-way post-tensioned flat slab.
This thesis enhances our understanding of two-way post-tensioned flat slabs to
determine the most efficient span for floor systems under gravity loads. The study aims
to develop design aid curves that streamline the design and review processes for
structural engineers. These aids are intended to enhance efficiency, ensuring cost
effectiveness and safety while facilitating rapid design iterations.
The primary objective of this thesis is to conduct a parametric study following the
guidelines and requirements of the Egyptian Code (203) to develop and plot the primary
design aid curves for two-way post-tensioned flat slabs. These curves will provide a
quick reference for determining the optimal span length, facilitating the calculation of
the required amount of prestressing steel for project feasibility studies, and enabling
comprehensive cost analysis.
This research can be separated into four individual parts. The first part introduces
the advantages and disadvantages of prestressed concrete, the analysis and design
aspects as well as the analysis and design methods according to the Egyptian Code
(ECP 203) that includes allowable losses and material properties corresponding to the
allowable stresses. This section also introduces the allowable data about the Span to
Depth ratio according to the different international recommendations, regulations, and
codes. It also outlines the available literature review about using RAM Conceptt
software package in the last fifteen years. Finally, we present a simplified numerical
modeling of a post-tensioned flat plate with bonded tendons to calibrate the used
procedures to ensure parametric study results.To guarantee reliable results, the second
step is calibrating the design techniques employed in Ram Concept Program. Simplified
numerical modeling of a post-tensioned flat plat with unbonded tendons is used to carry
out this calibration. A thorough rundown of the analysis and design processes utilizing
the RAM Concept software is given in the third section. It covers every step of the
procedure, including the creation of shop drawings and the choice of geometry and
structural system.The key design aid curves and the outcomes of the tested models are
displayed in the fourth section. The impact of span variation, various tendon
arrangements (uniform in one direction and banded in the other), variations in both dead
and live loads, and the influence of concrete compressive strength are the important
features of the parametric study that are examined. The research findings and specific
recommendations for future work are presented in this section's conclusion.

اصبح استخدام البلاطات المسطحة مسبقة الإجهاد أكثر شيوعًا نظرًا لمزاياها العديدة. ولفهم أفضل للبلاطات المسطحة ثنائية الاتجاه مسبقة الإجهاد تحت تأثير الأحمال الجاذبية، تم إجراء دراسة تحليلية وفقًا للكود المصري .(ECP 203) تهدف هذه الدراسة إلى تطوير منحنيات مساعدة أولية للتصميم تساعد المصممين في تحديد أطوال البحور المثلى لأنظمة الأرضيات وتحديد كمية الحديد المسبق الإجهاد المطلوبة. تتيح هذه المنحنيات للمصممين تقييم أطوال البحور بسرعة، وتحسين كميات الحديد المسبق الإجهاد، وإجراء تحليلات تكلفة لدراسات الجدوى. تتماشى هذه الطريقة مع أهداف تحسين الكفاءة الإنشائية وخفض التكاليف في تصميم البلاطات المسطحة مسبقة الإجهاد

Issues also as CD.

Text in English and abstract in Arabic & English.