cylindrical concrete tanks are commonly used in wastewater treatment plants. these are usually clarifier tanks. design codes of practice provide methods to calculate design forces in the wall and raft of such tanks. these methods neglect self-weight of tank material and assume extreme, namely ‘fixed’ and ‘hinged’ conditions for the wall bottom. however, when founded on deformable soil, the actu...

Guarantee of the strength for an aging structure, especially for a concrete structure, has been required. Possibility of the evaluation of a concrete structure using ultrasonic velocity has been investigated in civil engineering field in Japan. However, because the concrete is the complicate composite material which contains aggregates in mortar, and the ultrasonic propagation becomes complicat...

Methods which can be used to assess the chloride permeability of various types of concrete in a relatively short time are described. An electrical potential from 60-80 volt DC is applied either between a chloride solution ponded on a slab surface and the top of rebar mat, or between two faces at a core taken from a structure. The amount of chloride and sum of the electrical current which passes...

The shape optimization of gravity dam is posed as an optimization problem with goals of minimum value of concrete, stresses and maximum safety against overturning and sliding need to be achieved. Optimally designed structure generally saves large investments especially for a large structure. The size of hydraulic structures is usually huge and thus requires a huge investment. If the optimizatio...

In recent years, destructive earthquakes have shown the deficiencies of the existing buildings. One of the most effective mechanisms for dissipating the earthquake energy is inelastic deformation of the steel components. The objective of this research is to study the application of metallic dampers for dissipation of the earthquake energy and to investigate the behavior of concrete structures i...

Lightweight steel framing is a method in housing and construction that have been widely used in lightweight steel construction. In this method, the structure is built by cold formed steel elements. They are cost-effective, light, and easy to assemble. However, the performance of lateral load resisting systems in cold-formed steel structures specially the behavior of cold-formed steel shear wall...

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...

The effect of frequency content on the dynamic response of concrete gravity dams is investigated in this paper. Dams are one of the most complex structures to handle when there is dynamic analysis involved. One of the influential parameters on these structureschr('39') seismic response is the frequency content of the earthquakes. An index to represent frequency content, which represents frequen...