Earticle

The core aim of this dissertation is to empirically scrutinize a strength characteristic of beam-column frame subjected to the cyclic horizontal load, a beam-column frame of un-reinforced masonry wall constructed hard, and a shear wall frame. Lastly, the dissertation will suggest some solutions to improve the resistance capacity against earthquake regarding all constructions built with non bearing wall following having examining precisely all the analysis with regard to not only behavior properties and the damage mechanism of the beam-column frame and the beam-column frame of un-reinforced Masonry Wall constructed hard but also the resistance capacity against earthquake of non bearing wall and school buildings.

This paper presents vibration evaluation of floating structure which is located in Yeosu using acceleration responses data. In order to evaluate vibration usability, AIJ(1991) vibration performance criteria and ISO(2631-2) vibration criteria are considered. Natural frequency and acceleration responses are needed to apply those vibration criteria. Modal impact test was accomplished to obtain the floating structure's natural frequency. The acceleration responses from ambient vibration at 35 different points on a floating structure were measured. Then the first natural frequency and 35 points acceleration responses were applyed foreign vibration criteria for vibration evaluation of floating structure.

In this study, we shall investigate the dynamic instability behavior of Zetlin-type cable domes, which are well-known among the cable dome structures that the lightweight hybrid structure using compression and tension element continuously. The structural behaviour of the cable dome shows a strong nonlinearity according to the initial stress and external forces. Therefore, we determine the shape by applying initial stress abd then investigate the indirect buckling mechanism by the dynamic external force. Also, we investigate the generation of chaos in the indirect buckling, which the dynamic nonlinear problem is reacting sensitively by the initial imperfection.

This study investigated the replacement levels of recycled aggregate and Fly Ash, and examined the effects of strength development according to material age by measuring the tensile strength, compressive strength, and bending strength. Study results indicated that the compressive strength and tensile strength decreased as the replacement level of the recycled concrete increased, and that when Fly Ash is added to the mixture, the early age strength decreased while the long age strength increased by 0∼5%. In all strength tests, 10∼20% of Fly Ash mixing yielded the highest strength, while 30% of mixing showed rather lower strength.

In this study, to consider practical compressive zone of hollow slab, the equation for its flexural strength is proposed by the volume of compressive stress block according to neutral axis location in hollow section assumed. Existing estimation method of flexural strength of hollow slab considering only compressive zone above hollow part is evaluated as the most conservative method and the method estimating flexural strength by two alternative cross-section of hollow slab is evaluated as more practical method.

The purpose of this study is to present the damage detection method building structures by wavelet transformation. The damage location index using 1st mode shape is observed theoretically to find out damage location. The damage detection method is applied to numerical analysis model such as MATLAB for the verification. The shacking table test on 3 story building is performed for the examination of the damage detection method. Wavelet transformation and directly fast fourier transformation are performed for the mode shape, and damage index is compared. Finally the applicability of the wavelet transformation for damage detection is examined.

School or government office buildings, etc. There are many cases where a rigid frame structure between masonry wall installed to respond to the external force. In this case, seismic design of masonry wall is considered as non- structural elements, the national seismic design criteria does not take into account the influence of the masonry wall. However they are known to affect seismic performance considerably. In this study, using the capacity spectrum method was estimated the performance point, Displacement from a performance point compared criterion FEMA356 and, by examining the IO and LS performance level of the building permit to investigate the behavior of the buildings.

A connection of hollow structural section (HSS) has complicated details according to the connection type, and shows a very complex local deformation at the yield stress. Such various type of connections, Korea Building Code (KBC 2009) has suggested simple design equations because it was difficult to consider the complex local deformation. KBC 2009 has respectively proposed the design equations of the connections under axial force or moment, but it has not proposed the design equations of the connections under axial force and moment, simultaneously. In this paper, numerical analysis of the connection under combined load was carried out using the model based on the finite element analysis to ensure the reliability analysis.

In this paper, we designed and made isolation device and experimental structure through envelope design method base on energy balance theory and performed shaking table test to identify the dynamic response characteristics. The main parameters of this study were stiffness and yield strength of U-shaped steel damper and we analyzed acceleration, displacement, and internal force of isolation system in accordance with the main parameters. According to the increase of stiffness and yield strength of steel damper, there were growing tendency in response of upper structure. Based on this study, it is necessary for us to perform quantitative evaluation of isolation system through additional dynamic response analysis.

The dynamic characteristics of the structure must be understood in order to design an efficient active seismic controller. Evaluating the parameters with precision is very crucial not only for accomplishing a low cost controller, but for preventing the structural control system from unstable behavior. These characteristics of the structures can be estimated from the measured input-output data called the system identification. The purpose of the study is to evaluate the feasibility of the system identification method used in mechanical and electrical engineering applications to apply for the building structures subjected to seismic disturbance. The result of study that ARX model, ARMA model, ARMAX model can be suitable model to apply for building structure in the system identification.

The focus of this study was placed on the economy of the connection method for the main corners of steel frame plant column when small and middle size steel frame plant were designed. In particular, PIN and FIX connection method which were mostly used in plant construction were analyzed. Of the conditions(change in the span of width direction, crane load, and change in eave height) which were considered in this study, the change in the span of width direction and crane the load had not effect on the economy, while eave height which was most highly influenced by outer force(dominant load : wind load) had effect on the economy.

In this study the seismic evaluation applied to the school structure which had non seismic design to find out possible forecast positions when earthquakes take place. The findings are as follows. In order to improve a seismic-resistant ability it executes the seismic retrofit with steel frame, the necessary rate of steel frame of the school structure was built the drawings of standard for 1980's school structure compared with the whole was 15.3%, Changwon OO elementary school built in 1991 was 9.2%, and Geojae OO elementary school completed in 2004 was 7.2%, which meant that even though the sturcture were built without the consideration of seismic design, those which were relatively later completed had less necessity than the rest. The story drift after Seismic Retrofit with the methods shown above were all within the standard. In conclusion, the school structures which were built before 2005 when seismic design was required were better in terms of material strength, size of column, amount of rebar and structure standard than those which were built before 2005, so they could be reinforced with simple steel frame with lower cost, shorter duration of construction and not hide a range of vision.

In this study, non-linear static analysis was carried out to evaluate the seismic retrofit effect of retrofitted frame for the stiffness and strength ratios between reinforced concrete(RC) frame and steel damper system. The analysis results showed that the steel damper system could absorb more seismic input energy as its stiffness and strength ratios increase comparing to RC frame. While the absorbtion ratio of seismic input energy in case of low strength ratio was increase linearly, the absorbtion ratio was not increase proportionally in case of high strength ratio more than 1.

In this study, it was developed eco-friendly inorganic binding material concrete using ground granulated blast furnace slag and alkali activator(water glass, sodium hydroxides). Also, it was evaluated the flexure capacity of the RC beams using inoganic binding material concrete. The eco-friendly concrete using inorganic binding material encouraged alkali activation reaction has rapid hardening speed and showed possibility as a high strength concrete. Also, the RC beams applied this showed similar movement and destroy tendency with RC used previous cement.

Solar energy is expected to become increasingly attractive as an energy source because it is inexhaustible supply and non-polluting character, in contrast to the finite fossil fuels coal. But it is considerably affected by wind because it is mainly a lightweight structure and directly exposed to the outside. Nevertheless, wind resistance design criteria is unproposed and the previous study is not sufficient in this regard. Therefore, this study conducted the wind tunnel test to analyze the distribution of the wind pressure in accordance with the height of the lower part of Solar Collector. The experiment was conducted by changing each height to 0.6m, 0.8m, 1.0m, 1.5m, 2.0m, 3.0m, 4.0m with the minimum height 0.6m by safety engineering guide.

The present study is a study on structural safety according to installation heights of a solar tracker. For analysis, a generic structural analysis program of MIDAS Genw and a member design program of MIDAS SET were used. However, mechanical joint assembly was assumed to have secured sufficient safety for the analysis. Based on such analysis results, changes in the load depending on installation heights of the solar tracker and anchorage lengths of the structural frame and anchor bolt dependent on load changes will be examined so that a model will be presented securing the structural safety upon designing of a photovoltaic power generation apparatus.

Thanks to the formal factor, corrugated plate ability to resist a compression and shear is excellent although corrugated plate is thinner than flat plate. So the economical design is possible by it. But until now, a design standard for practical application is not enough and limit width-thickness ratio regulation on this is necessary. Therefore, it review primarily compression buckling strength of a corrugated plate through actual size compression experiment in this study. And it will provide a foundation for design standard preparation for bending member application of a corrugated plate after it analyze structural properties along width-thickness ratio. It made total 64 experiment plates with different conditions on thickness, height and width and verified structural merits of a corrugated plate through variable analysis.

This paper focuses on flexural strength of the CFRP-bar NSM R.C beams with polymer mortar adhesive. Through the comparison between the flexural test results and previous test results those of the epoxied CFRP-bar NSM specimen, this research provides that the mortared CFRP-bar NSM method shows a similar flexural performance with the epoxied CFRP-bar NSM and polymer mortar can also be used as adhesive in the NSM system

It is very important to access the damping ratio accurately in the wind design of tall buildings, but the damping ratio is not specified in the Korean Building Codes and thereby the values provided in foreign codes are adopted somewhat arbitrarily by engineers. The significant portion of concrete tall buildings in Korea has the shear wall structure system, and residential buildings have larger gravity load than buildings in other countries due to the use of floor heating system. Therefore, the damping ratio provided in foreign codes may not be directly applied to design of tall buildings in Korea. In this study, the damping ratio of actually built concrete buildings are measured and compared to those provided in foreign codes. It was found that damping ratio of tall concrete buildings decreases as the height of the buildings increases and the measured values are significantly smaller than 2.0% of the ASCE code.

In this study, non-linear seismic response analysis of reinforced concrete building with pilotis is carried out to confirm the validity of analysis model and method. The model of analysis is a specimen which was evaluated its seismic performance and dynamic response characteristics by the shaking table test. As a result of the analysis, periods are well matched with test results in elastic conditions. Also the tendency of the acceleration and displacement response are similar with the dynamic responses of shaking table test.

The purpose of this study was to suggest improvements in the seismic retrofit project of R.C school structure. For this purpose, a survey of the three schools which were located in Gyeongnam province and provided seismic retrofit after having been selected as the ones who were required seismic retrofit was conducted with the Post Occupancy Evaluation. This study estimated 10 steps which could be added to current project for the future seismic retrofit. The improvements suggested in this study and the measures announced by the technical department of Education and Science Ministry could help seismic retrofit projects effective.

The space frame structure is one of the large span structural system consisting of longitudinal and latitudinal members. The members are connected in three dimension. A space frame structure has high stiffness with a structure resisting external forces in steric conformation. According to many structural conditions, structural stability problems in the space frame are determined and considered very important. According to geometrical shape, the star dome, parallel lamella dome and three way grid dome were selected as models. The models were examined for characteristics of instability under STEP Excitations behavior according to rise-span ratio(μ) and shape imperfection.

Because of the urbanization process in recent years, many buildings are being constructed in a mountainous area. In this case, buildings can be damaged by topographic funnel effect, so topographic wind speed-up effects must be considered for securing the safety of structure. Thus, wind tunnel test conducted in order to investigate characteristics of wind speed-up effect. And this study compared topographic factor and turbulence intensity with experimental standard value through different horizontal measure points and different distance lengths between 2-Dimensional Hills. Through the experiment, the purpose of this study is to suggest quantitative fluctuation of wind speed according to the change of distance lengths and horizontal measure points between two 2-Dimensional Hills.

Currently, it is important to collaborate between each unit works in the construction industry. It is proposed the structural design process which can be used in the construction design phase and is established the prototype for brace connections based on BIM (Building Information Modeling). For this purpose, the prototype program which is capable of exchange the data between structural analysis program and 3D model was developed. It was given a simple example model in order to check out efficiency and productivity of it.

This study is to investigate the nonlinear behavior of reinforced concrete shear walls. This study were performed using the nonlinear analysis program CANNY. The existing experimental results were companed with numerical analysis results using the fiber-model. The nonlinear behavior were analyzed according to the variety of the length of the plastic hinge and the concrete elastic modulus. The initial stiffness, strength, displacement from the analytical results and the experimental results is slightly different, but the whole behavior was shown a similar pattern. Also lateral displacement values were found to change regularly according to an increase and decrease in the plastic hinge length and the concrete elastic modulus.

Many researchers in earthquake engineering are studying performance-based seismic design which could estimate behavior of structure like real structure and reflect the performance for minimizing damage due to earthquakes. So, approximate nonlinear methods have been studied to conveniently estimate nonlinear response of structure with sufficient accuracy and practicality. In this study, it is to examine effects of lateral force distribution in pushover analysis on approximate analysis of nonlinear seismic response of structure under earthquake load using nonlinear spectrum analysis(NSA). As a result, mode shape distribution shows better estimates than mass mode distribution.

As buildings become higher and larger, we become interested in usage, durability, safety and devising measures for solving problems is important. If there are especially cracks, iron reinforcing rods corrode and volume expands and it may cause collapse of a building. This study(thesis) aims to figure out features which fiber reinforced concretes which are mixed with various kinds of fiber, increasing strength for its reducing cracks and resistance by chloride penetration to analyze the data of each fiber permeated concretes with data results. For comparing and analyzing concrete strength and chloride penetration, as compressive strength grows, chloride diffusion coefficient tends to decrease. for fiber-mixed concrete, it is different depending on mixing rate. As a result, fiber mixing may reduce slightly corrosion of iron reinforcing rod.

This study aims to investigate casual relationships between personal characteristics and safety behaviors of the workers in the construction site and analyze the influence on the direct and indirect effects. The personal characteristics and the safety behaviors which should be incorporated into the theoretical model were identified and established by conducting literature survey. The model was verified by administrating survey questionnaires to the construction workers of 399 who are actively engaged in construction job-site located in Daegu metropolitan city and Kyungpook province. The data obtained from the survey questionnaires was statistically analyzed using SPSS18 and AMOS18.

Construction industry have a lot of uncertainty because it is an industry produces on orders for a specified client and various main persons of project are related. So many construction failure occur although advanced management systems are introduced. Construction industry need systematic and effective systems to prevent construction failure. But studies of construction failure are limited to construction phase. And there is no objectivity of data because construction failure only offer qualitative data. So this study analyze critical management factor of each phase using construction failure index(CFI). And this will provide basic data for system development on management of construction failure.

Advancements of construction technology enables to develop topnotch construction materials throughout R&D investment. However, it becomes challenges to adopt and apply the newly developed construction materials in practices. This problem is mainly attributed to not only the engineers’ negative attitude to the new technology, but also the absence of efficient way to deliver the up-to-date information. This paper presents a methodology of information sharing using catalogs and web-based interface that could provide an efficient way to deliver the up-to-date material information. The schematic architecture of data standardization presented in this paper would help increase the R&D competitiveness of material developers.