Earticle

The objective of this study is to find out the value of the Carry Over Factor (C.O.F) of a haunched beam. When the beam is prismatic, the C.O.F is 0.5. When  and the λ of the haunched beam increase, the value of C.O.F is also increases. Generally, the value of C.O.F of a horizontal haunch case is greater than that of an inclined one. Given the λ, the fluctuation range of the C.O.F of a horizontal haunch beam is greater than that of an inclined one. Therefore the horizontal shape of a haunch gives a more influence on the C.O.F than that of inclined one.

Therefore, this study suggested a simple analysis method using the flexural strength ratio of the transfer girder-wall to analyze structures with pilotis efficiently and the accuracy and usefulness of the suggested simple analysis method was verified through the analysis of example structures. Conclusions derived from this study are as follows. From the result of the simple analysis using a practical 3 dimensional model design, where the strength of the upper wall was modified as the ratio of 1/10～1/11 and analyzed in case of the flexural strength ratio of transfer girder-wall of the simple analysis method and the upper wall was separated as 4 bays at least, the flexural moment and shear strength of transfer girder showed higher figure by 1.03 times to 1.11 times compared to the detailed analysis and the result was similar to that of the detailed analysis of limited factors. When it is analyzed using the suggested simple analysis method, the figures of section moment, central moment and maximum shear strength required for the design of transfer girder proved to be estimated as Fail-safe.

A recent large-space structure is frequently made by light-weight structural system and it has a good mechanical efficiency. To make the light-weight structural system we are using tension members mainly. Since cable dome structures which are a soft structures are very flexible, stresses and nodal coordinates of the other members are changed when we control the stress of one member. Therefore we have to do two kind of works for effective and accurate construction of the cable dome structures. The first work is to make a working scenario to complete the final objective form, and the second is to revise constructional errors occurred in process of actual works. These works are called constructional analysis. In this study, we try to approach the constructional analysis of the cable dome structures using the numerical method, and then verify it.

Generally shear walls separated by opening composing core part of construction behave as coupled shear walls by connecting slaves or lintel beams and these coupled shear walls can make quite a little established moment caused lateral force of wind or earthquake efficiently resist lateral force through the frame behavior by coupling effect of coupling beams. Therefore the coupling effect of coupling beams is given a great deal of weight to efficiently control the lateral displacement. However during lateral force resistance, plasticity hinge is happened by concentrated stress of coupling beams and effective stiffness is decerased and serious problems of displacement control occur frequently. The post tension method of construction improves compression stress and hence improves flexural and shear capability than the established contract members by increasing the crak area moment of intertia, so the post tension method of contraction is highly evaluated. Accordingly if one use coupling beams by use of post tension, the resisting ability of coupled shear wall buildings against lateral force will be improved by advanced flexural and shear capability.

Almost low-rise reinforced concrete school structures are not applied in the seismic codes of Korea and seismic risks of existing reinforced concrete building are enlarging in Korea. Therefore, We have to provide effective earthquake preparedness against future earthquake to avoid a large seismic damage. For this reason, this paper has developed estimation method of seismic capacity for low-rise existing RC school structures. In this study, domestic and the other country's codes for estimation method of seismic capacity of existing RC school structure are briefly summarized and damaged school structures due to severe earthquake in Japan are examined. then, the feature of damaged school structures are analyzed for applying existing estimation method of seismic capacity. As the results, we proposed the new estimation method of seismic capacity through multiplying ductility index by first estimation index of seismic capacity, and the proposed estimation method is proved adequacy comparing to second estimation index of seismic capacity

An experimental and analytical study was performed to apply the friction pendulum system(FPS) to main control room of nuclear power plant. A friction pendulum bearing was fabricated and dynamic response of the bearing was evaluated. A partial model of main control room attached FPS was tested on the shake table. The model consisted of a cabinet, access floor(2.3m x 2.3m) and 4 friction pendulum bearings. Artificial time history based on floor response spectrum of main control room was used as earthquake input signal in the test. Comparisons between analytical study and experimental study were conducted in order to verify the results as well as to extend the experimental study to the range of parameters which could not be experimentally studied.

Indoor environment pollution problem of building is rising seriously to new social problem and effort to improve indoor environment is gone continuously taking advantage of nature data to construction material fare by one of way to solve this. Therefore, wish to analyze the special quality and experiment radon release one of room environment pollutant the latest because research that see uses charcoal to concrete bricks. The radon release rate displayed adsorption effect of maximum 70% as result of this experiment and manufacture of charcoal metathesis rate 20～30% is available by concrete bricks for structure in 1:2 charcoal metathesis rate 10～20% is judged by fact that practical use is possible as light weight brick in 1:7.

The purpose of this study was to analyze steel corrosion resistance of concrete containing copper slag. The specimens were made with normal portland cement and pozzolan materials with various replacement ratio and with W/B ratio ranging from 35% to 55%. Compressive strength, coefficient of chloride diffusion, corrosion area ratio and weight reduction ratio were determinated for the test. The results show that the concrete with pozzolan materials is superior resistant to chloride ions compared to the concrete without pozzolan materials. It was observed that blast furnace slag replacement ratio of 20% gives the best results with respect to chloride ion penetration and corrosion tests and observed that copper slag replacement ratio of 10% gives the seperior resistance compared to normal concrete.

Environmental pollution was placed in circumstance that is serious because seldom consider about environmental problem or users health problem and so on in modern society. When utilize zeolite powder as admixture for cement, is expected by something to reduce output of hazardous substance emitting in depression effect of leading persons and cement matrix itself that lead to sick house syndrome. Therefore, in this study, I expected by something to display function that can control but reduce hazardous substance that cause pollution of indoor air in case of finishing mortar and using zeolite powder. Hereupon, in this study, there is the purpose to construct basic data for suitability and utility as Environmental function material of mortar that mixing zeolite powder.

The study is propertys analyze such as the paste rheology, yield value and compressive strength etc. with used to the admixture micro powder manufacture high flow mortar, the purpose was the it`s obtain design of mix proportion of the high flow concrete or mix design necessary basic date. The result is admixture balance rate was highed according to the transposition rate to be good working a ball bearing flexibility. However, W/B is raised that it judge the unit volume weigh more than rising the flexibility is the huge affect according to the admixture`s transposition rate or addition rate of high range water reducing admixture. A special quality of mortar was according to the admixture transposition rate drop the early-age strength and it raising strength with keep dropping the W/B. It was reveal that as result of plzzoanic reaction of admixture is low early-age strength and high long-time strength. The conclude, in the more than variety of the mix condition that the research need about the high-fiuidity concrete of theory design of mix proportion or mix design method.

In this paper, the results of setting and strength properties of concrete incorporating cement kiln dust, fly ash and blast furnace slag respectively are reported in order to reduce hydration heat of mass concrete and achieve economical advantage. According to test results, setting time was not affected by CKD contents, whereas The use of FA with 10% and 20% retarded the setting time more than 2 hours. The increase of BS with 20 and 40% delayed setting time more than 1.5 hours. For compressive strength, the increase of CKD reduced the compressive strength. The use of CKD with 10% had little effect on strength gain. The use of FA and BS resulted in a reduction in compressive strength in proportion to the contents at early age. At 28days, compressive strength with FA and BS exhibited a parabola curve with an increase in FA and BS contents. Higher strength gain was achieved in 10% of FA and 20% of BS at 28days. It can be seen that the use of mineral admixture in mass concreting considering placing layer can reduce hydration heat and economical advantage

This experimental study is the fundamental report to propose the use of waste tile as pozzolanic admixture of concrete. This study performed pozzolan reaction test to examine the possibility of the use. Also, strength development properties and frezze-thaw resistance of concrete containing waste tile were studied. Pozzolan reaction ability test performed through phenolphtalein and condensation setting test. To investigate Strength development properties, waste tile replaced on portland cement in 10, 20, 30, and 40% weight ratios was used. Also this is studied in condition of air containg range of fresh concrete was 2±1%, 4.5±1.5%, 7±1% to investigate frezze-thaw resistance of concrete containing waste tile. The following are the summary of which concluded in this study. In case of waste tile replaced on portland cement, the proper replacement ratio was 10%. However, considering the concrete cured over 28 days compressive strength, 30% of replacement ratio was higher than plain concrete of that. The results of concrete containing waste tile at the air containing range has similar durability factor when comparing the plain concrete. If concrete containing waste tile has the air containing range 4.5±1.5%, that will have enough resistance against frost action.

The viscosity of high-flowability paste is very high compared to ordinary concrete for the low water-binder ratio(W/B). Therefore, high-flowability concrete is positively necessary to high-range water reducing agent. High-Flowability paste can make much higher fluidity with no occurrence of segregation, by its higher viscosity and lower yield value than ordinary concrete. The flowability of high-flowability paste must be evaluated not only by convention consistency test such as slump test but also by the base of the rheological properties of the fresh concrete. The purpose of this study is to analyze the physical properties of high-flowability paste according to the replacement ratio of the Polycarboxylate high-range water reducing agent.; high-flowability paste is considered as Bingham plastic fluid with the rheology parameters of the plaste viscosity and yield value.

This study investigated on mechanisms of peeling off in epoxy resins bonded repairing-strengthening materials. According to the experimental test, elasticity modulus of mortar indicated 16～26(GPa), and that of epoxy resins was around 45.3～220(GPa). In addition, steel plate for repairing-strengthening materials indicated 338(GPa), while Carbon fiber Bar was 34.1(GPa). This value of each materials having different modulus was announced in this paper. Furthermore, thermal expansion coefficients of each materials also had different value, such as 10～13με/℃ of mortar, 41～54με/℃ of epoxy resins, 11.93με/℃ of steel plate and -1.68με/℃ of Carbon fiber Bar, respectively. For the properties of dry shrinkage, an increase of mixture proportion resulted in higher shrinkage value of the mortar, and the increase of flow also exhibited higher shrinkage ratio.

The purpose of this study examines properties of matter of mortar by use of TiO2, I wish to quote basic data about ability mortar development that utilize TiO2. TiO2 used Anatase and rutile style two, and substitution and method of addition. Basis mixing ratio of cement mortar by water/cement rain(W/C%) 42.5% cement and sand weight ratio established by 1:2.45 and substitutes by each 0%, 3%, 6%, 9%, 12%, 15% about cement weight substitutions and adds and produced mortar. Properties of matter examination of mortar that use TiO2 powder measured flow test, compressive strength and bending strength. As results of flow, compressive & bending strength test, mortar using TiO2 is improved it's properties. Especially, the characteristics of pollutant removal of water is increased in accordance with admixture ratio of TiO2.

This paper reports the results of Mock-up test for concrete using drying shrinkage reducing superplasticizer(DSRS) in order to evaluate the validity of DSRS. The use of DSRS results in an noticeable improvement in compressive strength compared with other concrete. Drying shrinkage of concrete using DSRS is lower than that of conventional concrete by as much as 17% due to less water content and contribution of expansive additives to expansion of specimens. Drying shrinkage measured by contact gauge has the highest value at the thin section of the mock up member such as near the window. The use of DSRS can reduce drying shrinkage by as much as 15~30% comapared with conventional concrete member.

The purpose of this study is to analyze the strength development of concrete containing bottom ash as a part of fine aggregate. The experimental program included the measurement of concrete for compressive strength, splitting tensile strength, permeability, dynamic elastic modulus. The results of the experimentation are as follow. The compressive strength of concrete using bottom ash decreased according to increase of the replacement rate of bottom ash. The highest compressive strength showed at the replacement ratio of 30% bottom ash and 10% fly ash. The concrete containing CSA, CaSO4 as activator was effective on the compressive strength development. But the concrete using NaOH as activator showed a poor characteristic. In the case of using bottom ash, fly ash as fine aggregate, the concrete is waterproofed concrete than ordinary concrete by the pozzolanic effect.

Crushed sand is made by crushing the rocks artificially. With a wide shortage of natural river sand all over the region in Korea, demand for crushed sand are becoming increased. However, Informations as to crushed sand are insufficient. In this paper, the actual conditions of crushed sand related to producing and quality variation are investigated. 29 manufacturing company of crushed sand are reviewed. According to results, density of most crushed sand tested exceeded 2.5g/cm3, and absorption ratio meet the requirement of KS except one sample. For grain properties, passing amount of 0.08mm sieve satisfied the requirement of KS except one sample. Grain distribution of most crushed sand is estimated 54.26%. But 6 crushed sand sample did not meet the requirement of KS. Fineness modulus and grading are varied from manufacturing region. 18 samples of crushed sand among 29 samples deviated the minimum level of standard grading range by KS. Therefore, improvement of grain properties of crushed sand is urgently needed to manufacture better crushed sand.

As the efficiency of the construction has recently become important, the importance of VE(Value Engineering) is increasing and the application of VE is also practiced. On this, the main purpose of this study is focused on suggesting the way of improvement of construction VE through the examples of VE application in the inhabitant hall construction in K city which was ordered by considering the theory of VE and Turn-Key construction. This study deals with the application of VE in public rather than that in private. This study is to derive what the problem of VE application in the present domestic construction area by considering the theory of VE and the example of VE application in the inhabitant hall construction in K city. Finally, by the suggestion of the answer of the derived VE problem, VE can be performed smoothly and efficiently.

This study analysis the brand image of apartment which we want to notify consumers in current advertisement of apartment, and provided the basis of marketing through the discrimination by the investigation on what kind of brand image the consumers prefer according to the consumers characteristics based on the analysis. We expect that the results of this research will help the house building enterprises to cope with the present situation which the brand is playing an important role in the strategy of apartment marketing and the consumption desire of consumers and those results will be useful in the development of more competitive apartments.

Since having enacted the law related to the private financing about social overhead capital legislated in October 1994, the private financing projects have been settled down as the critical procedures to provide the social infrastructure. The private financing projects might not only benefit those social infrastructures such as school, welfare, and cultural facilities which need to be invested as quickly as possible in order to meet public demands, but it will lead private investment and make various private project procedures available provided that the BTL projects are activated properly in the field of education, welfare and train infrastructures. As a result of those market conditions of private financing projects, the procedures have been expanded to the newly confirmed projects and expected to hold the potential market size which might be equal to the BTO. Despite those beneficial factors, the steps reporting how to perform those projects, which one will be selected, and how to evaluate those proposals in Parliament are very complicated and difficult to go through. Consequently, the purpose of this study is to figure out the problems derived from BTL projects when compared with the traditional procedure in an educational area, and then provide the guideline to perform BTL projects efficiently and properly.

The Knowledge Management System, which is to create the value through managing knowledge, has been adapted by many foreign companies since early 1990's. Also, this management system has been introduced to some major construction companies of Korea. However, the special importance of knowledge in construction part make the sharing of knowledge hard, so the knowledge from that construction project has been missing currently, after accomplishing one project. In other words, under the paradigm of Knowledge management, companies do not support knowledgable workers and set up a system to take the lead by the effective usage of knowledge. Therefore, this study goes the background of adopting the Knowledge Management System and the characteristics of the Knowledge in construction field first and then, through the analysis of some construction company, this essay suggests the tactical framework for revitalizing the Knowledge Management System in Korean construction company.

The EAC(Estimate at Completion) among existing methods, which estimate cost and time effectively, help managers anticipate changeable several results at the point of 15～30% in the project progress. However, this method may cause such some problems as not to consider the periodically changing circumstances caused by construction risks or uncertainties which can affect the cost and time in the project, and to regard collected and accumulated data only as a single value when predicting the results on the progress. Accordingly, it is very difficult to accept the even small range of variability based on the anticipation of EAC. Consequently, the study focuses on the possibility methodology to anticipate time and cost accurately on the way to utilize EVMS(Earned Value Management System), and also suggest the way to perform the right estimation of EAC as considering various risks and uncertainties in construction projects.

Domestic construction industry must objectively prove their quality for customer by strengthening international competitive power and innovating internal quality cost system. Therefore, to gain outside trust, the need of the quality management is raising which is one of the way to construct quality cost system. Quality expenses are the expenses to gain quality as a part of the quality management. However most of them are consist of the failure expenses. In order to prevent the failure expenses, quality management must be used throughout the whole period of construction by well-organized system and enough expenses. Most of the people in the construction industry however do not have enough knowledge about the quality expenses. This research will get hold of the concept of the quality expenses. It will also analyze the recognition and state of the quality expenses during the accomplishing process of the domestic construction project. It will find out to solve the problems applying the quality expenses. Finally, it will indicate the way to improve for efficient application of quality cost system

After breaking down Sung-Su Bridge and Sam-Pung Department, inspection and maintenance of buildings in korea have carried out 26,459 buildings through the special law for building safety. It leads to reduce safety accidents and enhance the way of thinking for safety. By researching the current situation of safety inspection work process, this paper get a few problems : no-exist standard form, the unsuitable work process, and so on. The purpose of this paper is to analyze the current situation of safety inspection and result in few problems. It can get the circumstance : what kind of buildings need to do safety inspection, how many inspection facility do, and the situation of detailed inspection and detailed safety diagnosis. To sum up, if we would solve these problems, it could increase the quality of building maintenance for life cycle and get the long life of buildings with standard safety inspection.

concrete applying to high rising building. The main experimental variables were water/binder ratio 39.0, 41.0 and 43.0%, water content 160kg/㎥ and replacement ratio of fly-ash 0, 10, 20, 30(%) . According to the test results, the principle conclusions are summarized as follows. 1) The optimal mix design that was gained from the results of inside experimentation considering fluidity and durability under the status of fresh concrete is shown the water/binder 40% and the replacement ratio of fly-ash 25%. 2) The results of analyzing of hydration heating, it was shown that the cracking by hydration heating was reduced very much by using the P.E Film and the sheet on the surface.

Recently the study on high flowing which has high workability and self-compacting is being proceeded actively in the university and corporative laboratory. The new kinds of cement as changed by its chemical composition and high range water reducing agent enhancing the workability of concrete having been developed, keeping pace with this tendency. The purpose of this study is aimed for investigating the rheology property and fluidity of cement paste, by changing the substitutional ratio of an admixture, additive dosage of Naphthalene Sulphonate high-range water reducing agent. from result, the fluidity and rheology of paste were different according sorts of powder and additive dosage of agent.

According to the test, An increase of super-retarding-agent (SRA), which combined the SRA with admixture, delayed initial and final setting time. Interestingly control concrete incorporating only admixture also retarded setting time. In addition concrete, adding combination of the SRA and admixture simultaneously, exhibited considerable results, due to the absorbing, pozzolanic and potential hydraulicity reaction of the admixture. Overall, to secure initial setting time as control concrete does, particular coefficient value considering the properties of each materials, should be applied, before it is placed in the field construction.

In this study, we analyzed the The rheological properties of high flowability paste mixing cellulose type viscosity agent. and we suggest that the algorism of a mixing plan in the high flowability concrete and from this, we show the basic report for the right mixing plan. From the results, the yield value and the plastic viscosity is increased in proportion to the added amount of viscosity agent. among the Viscosity Agent, 50us is better than 40us in the plastic viscosity, but is less than in the yield value. this is the fact of the low yield value of the high flowability paste and the flowing Properties with the right Plastic Viscosity. so we concluded that 50us is better than 40us as a viscosity agent of the high flowability concrete.

In this paper we studied the kind and the legal standards of the floor impact sound and also understood a fundamental conception of the floor impact sound is based on the research and analysis of the literature written in the inside and outside the country. And a range of the paper is to grasp to actual state of the floor impact sound through a survey and field and present legal, material and structural solutions on the floor impact sound of apartment houses. The result is as follows.; Most apartment house tenants have suffered severe damage from a floor impact sound demands on substitutes and a method of construction have been increased. Constructors have pointed out many problems concerning the standard floor system of the government but normally they have applied a government bill considering all sorts of civil appeal on the construction environment sand a legal strife getting increased recently. Actually the standard floor system has been not satisfied with the first grade standard on the sound insulation and it will be required the necessity of certification on diverse floor structure system based on the related materials for a buffer or a shock-absorbing device and technical development to the future.