Joonam Park

• Wonkwang University

The effect of different parameters on the solution of the problem can be investigated through parametric analysis. In this study, the parametric analysis was conducted to determine the effect of concrete compressive strength on the airtightness performance level of the prestressed concrete tube structure. The finite element analysis approach (FEA)...

This research was funded by Wonkwang University in 2019.

The super speed tube transport (SSTT) system is considered as a strong candidate for next-generation long-distance transport systems because of its anticipated highly efficient performance. Several studies have been conducted on infrastructure systems using concrete to improve the construction and economic feasibility of SSTTs. However, most of the...

The super-speed tube transport (SSTT) system, which enables high-speed transportation in a partially vacuumed tube by minimizing the air resistance, is drawing attention as a next-generation transportation system. To evaluate the applicability of concrete as a material for the system, the effect of cracks on the airtightness of the system needs to...

Seismic risk assessment of unreinforced masonry (URM) buildings is an important process for seismic retrofit of essential facilities located in the central and southern United States (CSUS), as more than 30 % of facilities there are low-rise URM buildings. Although HAZUS, the current loss estimation package for natural hazards, provides a set of fr...

An analytical model is developed to evaluate airtightness, which is one of the most important requirements of vacuum tube transportation systems. The main objective of the model is to anticipate the pressure inside a closed structure, which initially decreases and then rises with time owing to the inflow of the air outside. The model is formulated...

A Super-speed Tube Train (SSTT) system is considered to be an alternative transportation system where trains could operate as fast as 700 km/h by reducing the air resistance in a vacuum tube structure. One of the most important technical requirements for design of SSTT system is assuring the airtightness in vacuum tube structures. In this paper a p...

In this paper, a reliability analysis is performed where the pressure change inside a concrete tube is probabilistically estimated considering the uncertainties inherent in the material and the system discontinuity. A set of uncertain quantities related to the equivalent system air permeability and the atmospheric pressure, are defined as random va...

In the conventional approach for analytical fragility analysis of structures, a single set of seismic fragility curves is developed and utilized for risk assessment of structures having the same classification. This approach implicitly assumes that all structures corresponding to the same classification undergo the same level of damage under a give...

A super-speed tube train (SSTT) system is a conceptual alternative transportation system where trains could operate with a practical speed as high as 700 km/h in a vacuum tunnel, which minimises air resistance. This paper presents the results of a preliminary study involving an airtightness performance evaluation of a concrete vacuum tube structure...

This study suggests the utilization of heat of hydration of concrete to activate the shape memory effect (SME) of shape memory alloy (SMA) wires embedded in concrete and produce recovery and residual stress on the wires. This method is more convenient than the previous electronic resistance heating. For the purpose, this study prepares NiTiNb SMA w...

Shape memory alloy (SMA) wire jackets for concrete are distinct from conventional jackets of steel or fiber reinforced polymer (FRP) since they provide active confinement which can be easily achieved due to the shape memory effect of SMAs. This study uses NiTiNb SMA wires of 1.0 mm diameter to confine concrete cylinders with the dimensions of 300 m...

This paper outlines a decision framework that incorporates state-of-the-art earthquake engineering information and decision maker preferences into multicriteria decision models to support earthquake risk mitigation decisions. Seismic risk analysis of a structure is utilized for probabilistic estimation of the anticipated seismic losses, which in tu...

This paper introduces a new steel-jacketing method for reinforced concrete (RC) columns using external pressure. Experimental tests of concrete cylinders and RC columns are performed to assess the effectiveness of the proposed method. Single- and double-layered jackets are introduced. The newly jacketed cylinders show good results in terms of incre...

This study used prestrained NiTiNb and NiTi shape memory alloy (SMA) wires to confine concrete cylinders. The recovery stress of the wires was measured with respect to the maximal prestrain of the wires. SMA wires were preelongated during the manufacturing process and then wrapped around concrete cylinders of 150 mm×300 mm (×L). Unconfined concrete...

This study presents a risk-based decision support framework for seismic retrofit of building structures where the decision criterion is to minimize the sum of the cost required for the rehabilitation and the expected seismic loss over a specified time period. Probabilistic seismic hazard model (PSHM) and probabilistic seismic demand model (PSDM) ar...

Unreinforced masonry (URM) is one of the most common structural types for low-rise buildings in the United States. Its dynamic behavior is highly nonlinear, and generally shows high vulnerability to seismic loading. Despite the need for seismic risk assessment of this class of structures, the fragility curves for URM buildings based on analytical m...

This study examined the application of passive energy dissipation systems for response modification of essential facilities in the Mid-America region. Essential facilities are defined as buildings that support functions related to post-earthquake emergency response and disaster management. For such buildings simply insuring life safety and preventi...

Consequence-Based Engineering (CBE) is a new paradigm proposed by the Mid-America Earthquake Center (MAE) to guide evaluation and rehabilitation of building structures and networks in areas of low probability - high consequence earthquakes such as the central region of the U.S. The principal objective of CBE is to minimize consequences by prescribi...

Passive energy dissipation devices have been successfully implemented in buildings around the world to reduce structural response, primarily due to earthquakes, but also for wind and other dynamic loading conditions. The basic objective in using passive energy dissipation devices is to try to concentrate as much of the energy dissipation as possibl...

Seismic vulnerability of building structures can be reduced with appropriate rehabilitation schemes. However, decisions on rehabilitation of structures can depend on multiple conflicting criteria such as cost, life loss, functionality, etc. In this study, a framework is developed to support decisions on seismic structural rehabilitation. Three mult...

M.S. Donald W. White

Seismic rehabilitation of structural systems is an effective approach for reducing potential seismic losses such as social and economic losses. However, little or no effort has been made to develop a framework for making decisions on seismic rehabilitation of structural systems that systematically incorporates conflicting multiple criteria and unce...