in this paper the seismic evaluation of reinforced concrete structures in petrochemical facilities under sever conditions such as high pressure, high temperature and corrosive environment is studied. these structures were designed and constructed during 1976-78. the evaluation procedure is basically performed in two phases namely; a) qualitative and b) quantitative methods. in the qualitative e...

This study focuses on the shape optimization of concrete gravity dams considering dam–water–foundation interaction and nonlinear effects subject to earthquake. The concrete gravity dam is considered as a two–dimensional structure involving the geometry and material nonlinearity effects. For the description of the nonlinear behavior of concrete material under earthquake loads, the Drucker–Prager...

Elevated rail transit has been developed in some big cities in China in recent years. However, specialized codes for design of the bridges in the elevated rail transit system have not yet been established. Based on the prestressed concrete (PC) box girder bridges on Guangzhou metro line 4, some technical features of design principle and technology requisition, ensemble plan and design load of b...

corrosion of steel reinforcement is one of the most prevalent causes of reinforced concrete (rc) structures deterioration in chloride-contaminated environments. as a result, evaluating the impact of any possible corrosion-induced damages to reinforced concrete bridges strongly affects management decisions: such as inspection, maintenance and repair actions. the corrosion propagation phase is a ...

Steel-concrete-steel (SCS) sandwich panels are composed of two steel plates with low thicknesses and high densities and strengths and one thick layer between both plates with low strength and density known as core that is composed of concrete. Cohesive material-epoxy resin or shear connectors are usually used to connect the plates to the concrete core. SCS sandwich composites are being develope...

Shape memory alloys (SMAs) are unique smart materials that have many advantages, such as ability to resist large strains without leaving residual strains and ability to recover original form. However, the high costs of SMAs have limited their usage. This paper evaluates the behavior of concrete structures equipped with SMAs in an optimal manner as they are being used along the plastic hinge of ...

in practice, foundations are settled on the soft layers of soil, so the ground must be designed as well as the structure. wave propagation and hysteresis damping of soil layers may alter the seismic response of flexible-base design in comparison to controversial fixed-base. lots of uncertainties about this issue, necessitate most of seismic design standards including iranian standard no. 2800 t...

Precast prestreesed concrete braces are a new method for seismic strength of Concrete Structures which has the following benefits: a) no wet concrete work in construction site b) No bolt or anchorage to the existing frame c) easy to apply d) short construction period e) low construction cost, to evaluate seismic performance of strengthened structure a model consist of existing frame and concret...

Imaging techniques are high in demand for modern nondestructive evaluation of large-scale concrete structures. The travel-time tomography (TTT) technique, which is based on the principle of mapping the change of propagation velocity of transient elastic waves in a measured object, has found increasing application for assessing in situ concrete structures. The primary aim of this technique is to...