We analyze the concrete security provided by a signature scheme described in a recent Internet Draft by McGrew and Curcio.

The effect of water-borne contaminants on the durability of concrete is well-known and cracked concrete is more susceptible to permeation of these contaminants. An approach to autonomic self-healing of such concretes is the utilization of microbiologically-induced calciteprecipitation. This approach uses the metabolic activity of bacteria and biomineral precursors embedded within the concrete t...

ABSTRUCT: Recently, in the attention in response to global warming issues and sustainable society, the manufacturing using natural materials has become actively. Bamboo, low cost, fast growing, and broad distribution of growth, is expected to contribute significantly to earthquake-resistant construction and seismic retrofit technology in the developing countries. The authors also have been stud...

Concrete is a long-lasting and less energy consuming construction material than steel and Aluminum. However, the concrete industry is the single largest consumer of natural resources. Several places around the world are facing faster rates of depletion of the resources needed for the manufacturing of portland cement, mining of aggregates, and water for making concrete. Each one of these materia...

This paper presents an experimental study on circular stirrup-confined concrete specimens under uniaxial and monotonic load. The effects of stirrup volume ratio, stirrup yield strength and concrete strength on damage evolution of stirrup-confined concrete were investigated. The experimental results showed that the strength and ductility of concrete are improved by appropriate arrangement of the...

Various nondestructive evaluation (NDE) techniques have been studied to locate steel rebars or dowel, and to detect invisible damage such as voids and cracks inside concrete and debonding between rebars and concrete caused by corrosions and earthquakes. In this study, the authors developed 3-dimensional (3D) electromagnetic (EM) imaging technology to detect such damage and to identify exact loc...

The premise of this paper is that low water-to-cement ratio (w/c), higher strength concrete may undergo substantial volume changes, especially at early ages (< 24 hours), and the prevention of these volume changes can lead to invisible micro-cracking as well as visible through-cracking. This paper compares the predicted response of concrete undergoing autogenous shrinkage using two different mo...

The atomic polymer technology in form of mesoporous inorganic polymer (MIP) can effectively improve material durability and performance of concrete by dramatically increase inter/intragranular bond strength of concrete at nano-scale. The strategy of MIP is fundamentally different from most additives currently on the market for industrial applications. When MIP is added to a concrete or masonry ...

In internal curing, pre-wetted lightweight aggregates (LWA) serve as internal reservoirs to supply the extra water needed by the cementitious and pozzolanic components of the concrete during their hydration processes. Due to their porous nature and reasonably high absorption capacity, the LWA can also be filled with other materials, such as phase change materials (PCMs). In this paper, three po...