Reducing Thermal Cracking of Mat-foundation Mass Concrete Applying Different Mix Designs for Upper and Lower Placement Lifts

‏‎suppression of coke formation in thermal cracking by coke inhibitors‎‏

‏‎the main purpose of this research was to:1.develop a coking model for thermal cracking of naphtha.2.study coke inhibition methods using different coke inhibitors.developing a coking model in naphtha cracking reactors requires a suitable model of the thermal cracking reactor based on a reliable kinetic model.to obtain reliable results all these models shall be solved simultaneously.for this pu...

Mix proportioning of high-performance concrete by applying the GA and PSO

High performance concrete is designed to meets special requirements such as high strength, high flowability, and high durability in large scale concrete construction. To obtain such performance many trial mixes are required to find desired combination of materials and there is no conventional way to achieve proper mix proportioning. Genetic algorithm is a global optimization technique based ...

Experimental and Numerical Studies of Controlling Thermal Cracks in Mass Concrete Foundation by Circulating Water

This paper summarizes an engineering experience of solving the problem of thermal cracking in mass concrete by using a large project, Zhongguancun No.1 (Beijing, China), as an example. A new method is presented for controlling temperature cracks in the mass concrete of a foundation. The method involves controlled cycles of water circulating between the surface of mass concrete foundation and th...

Upper and lower bounds for numerical radii of block shifts

For an n-by-n complex matrix A in a block form with the (possibly) nonzero blocks only on the diagonal above the main one, we consider two other matrices whose nonzero entries are along the diagonal above the main one and consist of the norms or minimum moduli of the diagonal blocks of A. In this paper, we obtain two inequalities relating the numeical radii of these matrices and also determine ...

Evaluating Cracking In Concrete