nanotechnology is a favorite research area that revolutionized mechanical and chemical properties of materials. recently, focusing on concrete as a porous material with micro-scale and nano-scale pores enthusiastic researchers developed their investigations to find out microstructure and mechanical properties of concrete. the aim of this paper is to investigate the effect of nano-silica as an a...

Estimating mechanical properties of concrete before designing reinforced concrete structures is among the design requirements. Steel fibers have a considerable effect on the mechanical properties of reinforced concrete, particularly its tensile strength. So far, numerous studies have been done to estimate the relationship between tensile strength of steel fiber reinforced concrete (SFRC) and ot...

large capacity cylindrical tanks are used to store a variety of liquids. their satisfactoryperformance during earthquake is crucial for modern facilities. in present paper, the behavior of cylindricalconcrete tanks under harmonic excitation is studied using the finite element method. liquid sloshing, liquidviscosity and wall flexibility are considered and additionally excitation frequency, liqu...

   This paper reviews some progressive studies and innovations in cement and concrete materials in nano field. Due to the widespread acceptance of the special properties of nano materials and using them for engineering concrete performance, understanding and directing their properties are not achievable without instructing concepts and investigating interactions among components. Due to ach...

The columns of frame structures are the key load-bearing components and the exterior columns are susceptible to attack in terrorist blasts. When subjected to blast loads, the columns would suffer a loss of bearing capacity to a certain extent due to the damage imparted which may lead to their collapse and even cause the progressive collapse of the whole structure . The concrete-filled steel col...

Waters’ variant of the Boneh-Boyen IBE scheme is attractive because of its efficency, applications, and security attributes, but suffers from a relatively complex proof with poor concrete security. This is due in part to the proof’s “artificial abort” step, which has then been inherited by numerous derivative works. It has often been asked whether this step is necessary. We show that it is not,...

The purpose of this study is to determine what type of preventative maintenance for a concrete parking structure will produce the maximum economic benefit. Existing models for concrete deterioration are analyzed for their accuracy in predicting the service lives of concrete structures and a model appropriate for concrete parking structures is selected. The selected model is modified to account ...

Corrosion of steel reinforcement related to the intrusion of chloride ion is still the main threats to the durability of concrete structure, especially in marine environment. For the purpose of delaying the Cl− concentration at the surface of steel reinforcement reaching the critical value leading to initial corrosion, the permeability of concrete is usually improved by optimizing the concrete ...

In this note, we describe an error in the proof for CLRW2 given by Landecker et al. in their paper at CRYPTO 2012 on the beyond-birthday-bound security for tweakable block ciphers. We are able to resolve the issue, give a new bound for the security of CLRW2, and identify a potential limitation of this proof technique when looking to extend the scheme to provide asymptotic security.