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In the cost planning phase, this study offers a process which is predictable contingency and predicts the range of fluctuation of the cost, taking an advantage of EVM in construction phase. With reflecting the results from this procedure, this study presents a process, rationally manageable contingency. The result of this study is following (1) The performance index can't be accepted through all of the projects because of the existing EAC method's limitation to measure it only at a single point of the projects. (2) This research makes the decision makers get the information as much as they want to collect on the basis of the fact to suggest a range of the fluctuation with the three results such as lower, average, and upper limit, not the single value of the EAC. (3) Each case study, reflecting the similar features in the early state of the projects, passes through the processing of regression analysis, and then the contingency can be estimated. (4) The simultaneous regression equations on both ACWP and BCWP can be developed by collecting the actual data about cost and time of the projects by the time to measure the performance index. (5) Consequently, the reports of the fluctuating range of the EAC are able to be on the desk of the decision-makers after estimating CPI and SPI with the expected ACWP and BCWP.

Our country private Finance Initiative begun in 1994 is revised by private investment method in 1999 at and private investment business was activated. Recently Korean private investment business is bringing big change in SOC business. Also, private investment object equipment was magnified sharply in new society base equipment type such as school by BTL(construction - move - lease) way, welfare facilities by private investment law revision January, 2005. Therefore, do that analysis for a case of the foreign countries that Private Finance Initiative operating (PFI) by this way need. So, research that see wishes to grope alternative accordingly with assignment before direction through positive analysis that is in PFI projects. Also, grasp original meaning of PFI, and examine efficiency of finance expenses in business propriety side.

In this study, we select a site adopting real composite precast concrete method. Estimating real construction cost and imaginary cost appling reinforced concrete method in the site, we compare the costs. Through using high intensity concrete and prestressed concrete, amount of concrete is reduced more than 50% but there isn`t big gap in material cost. In the main construction cost of composite precast concrete method, the material cost with production cost and transportation cost are in that, joints and topping concrete are account for 90%. But in case of reinforced concrete, labor cost spent at concrete steel bar and form is account for 30%. In the cost of attached, compared with composite precast concrete method, the reinforced concrete method taken in big portion by temporary work and scaffolding is twice as much as composite precast concrete method in construction cost. Therefore, economic efficiency is excellent reducing 11% total cost of composite precast concrete method from the reinforced concrete method.

We used some materials, so that a few cements, additives and pigment, to test the durability of concrete. The method of the test was KS F 2403(Method of making and curing concrete specimens), KS F 2405(Method of test for compressive strength of concrete), KS F 2441(Testing method for comparing concrete on the basis of the bond developed with reinforcing steel), KS F 2456(Testing method for resistance of concrete to rapid freezing and thawing), KS F 2711(Testing method for electrical indication of concrete’s ability to resist chloride ion penetration). In result, we could improve the durability of a white color concrete and construct successfully.

Worldwide, Certification systems for standard of material and quality of product exist very variously. Korean industrial Standard (KS) is most representatively certification systems in Korea. But laboratory of korea uses often ASTM, RILEM and JIS and these standards do not get into unionization. So, granted that experiment is same, result still can different. Specially, the difference occurs of concrete chloride test. Therefore, this research measured chloride amount of hardened concrete using identical material and wished to improve accuracy of chloride estimation as that comparison evaluate to each examination.

The information of a building project has not been managed in the integrated manner. For this reason, data handling work load has not been reduced despite the development of individual computer applications. Recently, BIM (Building Information Modeling) enabling integrated information management over project process has attracted attention in the industry. Its implementation based on the 3D project model will enable participants to obtain and process data timely without unnecessary data input. Building industry clients who do not have enough knowledge to make decisions in the earlier project phase can be also supported properly. According to the field survey that investigates the required information for clients, they want to compare costs of alternatives. An application to calculate cost by connecting cost data to objects in the project model created in the 3D object-oriented CAD is likely to present a solution to this end. This paper aims to present a scheme of the system and results for its validation.

systems to way for result improvement of quality management system, importance of quality cost is emphasized in construction industry. Systematic collection of quality cost information and development of quality cost system for analysis are required first of all for practical use of quality cost information. But, research about construction quality cost system of internal is real condition that is unprepared, and diverts quality cost system that is developed in advanced abroad to measure quality coste, but quality cost information that offer has been limited and practical use of quality cost information collected is difficult real condition. Analyze component part and merits and demerits irradiating quality cost system fee of construction, this research develops in advanced nation through literature research, and take advantage of 5W1H's principle with this and presented construction quality cost system improvement inside.

The insistence of rights and interests in contract is being generalized by opening in construction market which is following F.T.A, internationally. Conditions of contract in construction have different specialities compared with other industries. Different conditions of contract should be established because of a specific character that is different from each construction, such as work, environment, circumference conditions. Although the order of Turn-key is being expanded by increasing construction scale and demanding hybrid function, the suitable regulations of contract are not settled. As a result, various factors of claim is occurring in Change Order-Claim, because they just obey a part of guide-line. This study suggests useful analysis method in detail concerned with the main factor of Change Order-Claim by each D/B phases.

Both the open to the domestic construction industry and the region of international industry is expanding. Due to the change, the severe competition of construction companies among the developed countries which hold the state-of-the-art technology has rapidly increased. However, the construction contractors recognized the unexpected problems which are made after the completion of the construction work, so, they found out the need for the quality control system to avoid fault constructions in the construction industry. In the domestic construction industry, there are much difference caused by lack of communication between the owner and the builder as well as the lack of knowledge about the construction work. Accordingly, in this research, we can find out the problems deduced by the analysis of recognition and application of the quality cost and, in the end, we suggest the solutions. Furthermore, the research is focused on the communication in the construction industry to establish the knowledge basis about the quality cost by analyzing the information and technology of the developed countries.

survey had been made to identify decreasing factors of productivity. Targets of the survey were designers who is working in design offices. From the questionnaire survey, the causes of decreasing factors of productivity were identified and the result was obtained. Based on the result, the design management process was developed. The conceptual basic theory of the model was adopted from lean construction principles which emphasized the reducing wastes in construction process. This study suggested five procedure modules for a conceptual design process model. Consequently, the quality of design will be possibly guaranteed with this conceptual model, and the improved quality of design also can help to make productivity improvement in the construction phase.

This study investigates the fundamental properties of concrete using recycled coarse aggregate produced by bar-crusher. Test showed that using bar-crusher (s) had the most favorable results in fluidity and air content, compared with con-crusher (C), impact-crusher (I) and control concrete. In addition, increase of turning velocity rate of S, incorporating ratio of recycled aggregate and maximum size of aggregate caused increase of fluidity. Meanwhile, using S and C exhibited effective compressive strength value than I. For the turning velocity of S, C and I, most specimens showed less than 10% of strength reduction, which is acceptable. At the rate of 500ppm, the strength of concrete had the most favorable value. Even though an increase of incorporating ratio of recycled aggregate decreased the strength value, using less than 25% of incorporating ratio exhibited less than 10% of strength reduction ratio. This is determined that 25% of incorporating ratio of recycled aggregate will have favorable performance.

construction materials. For conserving natural aggregate resources, the waste concrete can be recycled as a important construction materials. Until now, the recycled aggregate manufactured from the waste concrete has been taken a side view of concrete. For the promotion of consumption of recycled aggregate, it is very important to make a study of manufacturing construction waste into good quality recycled aggregate and developing practical use for it. In this study, we investigated the evaluation for properties of recycled fine aggregate, produced by wet process, according to the ratio of the construction waste, and the effect on basic properties of recycled aggregate concrete.

The purpose of study is to improve the quality of recycled fine aggregate thet is generated from waste concrete. It is experimented with Abrasional Crusher over a kind of washning water. And Used it is carbonated water, acid water . Test items is the density, absorption ratio, passing ratio, XRD and XRF . As a result of the study, the more old mortal that is contained in the recycled fine aggregate through Abrasional Crusher process is removed, the better the quality of recycled fine aggregate is improved

This paper investigates the temperature history of slab mock-up specimens with various surface curing sheets, in order to determine a favorable surface curing method in hot weather condition. Test showed that insulating double bubble sheets+aluminum foil simultaneously on the upper section of a specimen prevented an increase of sudden temperature and a decrease of vaporization when placed during the hot weather condition. It also secured the high strength in early age. Therefore it is found that combination of the double bubble sheets+aluminum foil on concrete surface leads to reduce the plastic and drying shrinkage and enhance the early strength, thus improving the concrete quality.

This study investigates the engineering properties of concrete using recycling water, designed with various content of saccharic based stabilizing agent(SSA). Test results showed that increase of SSA inclined the fluidity of fresh concrete. As waiting time of recycling water before use increases, the fluidity of concrete decreased. In addition, the air content of specimens using more SSA recovered the value, which is comparable with control concrete, and delayed the setting time. However, the setting time of the specimens improved when used recycling water after 3 days. For the properties of compressive strength, specimens using recycling water increased the value, compared with that of control concrete, and it was maximized at 1 days of waiting time and overall 0.2% of SSA adding ratio.

In accordance with the national trend, although research about deflection of reinforced concrete that use nature aggregate in domestic research had been studied, they have prescribed to use the recycled aggregate compulsorily in case of over construction scale as an applicable construction of "Law about contract that the nation should be a contracting party" since 2005. However, although it has still obligated to use the recycled aggregate based on "Recycled aggregate quality standard" by Construction and Transportation Ministry, actually its study on long-term deflection of recycled aggregate is an unsatisfied situation. Therefore, the purpose of this study is to resolve the technical problems for cycling concrete through its experiment and analysis of long-term deflection by the substitution rate of recycled aggregate.

Recently, construction method and form system are gradually simplified according to the deficiency of human power and the increase of construction cost. The form system as a temporary structure needs many workers and includes many dangerous factors during installation and removal. Therefore, this study presents the permanent wall form system to provide the two functions of form and insulation, and to simplify the installation process without removal works. This wall form system consists of the double insulation materials and metal web for the security of safety, insulation and soundproofing. For the field application of this form system, the safety and serviceability of the form should be secured. To this end, this study evaluates the lateral pressure capacity of the system through the structural experiments considering actual field conditions.

Recently Ministry of National Defense is reconstructing old facilities using modular construction method for enhancing soldiers' quality of living. In the future, the use of modular construction method is expected to be increased. But in beginning stage as ROK military facilities that was built by modular was not designed and constructed efficiently, problems for pilot projects need to be analyzed by phases and construction methods should be improved. For the maximized efficiency, design should be made to minimize on-site works, factory automation in an assembly plant should be installed for the better productivity, roads that will be used for transportation should be checked, and joint and connection methods between modules in on-site assembly should be improved for a better quality.

The purpose of this study is to develop the LCC analysis system which is suitable business practice for the BTL projects. The scenario of prototype system model shows main functions and detailed modules about LCC analysis system which we will develop. The result of this study is as follows : establishing five kinds of cost factors(Initial cost, Operation cost, Maintenance cost, Energy cost, Disposal cost), developing of Cost Breakdown Structure and a Calculation system about cost factors, indicating development methods of this LCC analysis system.

To examine possibility to product particular cement appling control a specific particle character of cement, the study takes samples of OPC, minute particle cement and large particle cement of the progress to product OPC. to make progress a basic experimentation of mortar property. this is the result. fluidity and air content of minute particle cement and large particle cement are similar to OPC mortar, and a setting phenomenon of minute particle cement is faster than any others. n specific character manifesting strength, the primary stage`s compressive strength(16.7MPa) of the first day of minute particle cement is similar to the compressive strength(18.3MPa) of the third day of OPC mortar, and the primary stage`s compressive strength of the first day of the mix of OPC and minute particle cement mortar manifest 11.9MPa. There for, minute particle cement can be alternate instead of high strength cement which is being distributed. However, to apply smoothly according to economical efficiency and request of a site, it is to use the mix of OPC and minute particle cement suitable to ensure a high strength property.

combined effects of chemical actions by containing chlorides and the freeze-thaw action is also a problem which has not yet been fundamentally solved. Furthermore, surface deterioration of concrete was considered as accelerate factor of concrete durability tended to decrease. This study presents the experimental results of frost durability including resistance to freezing-thawing and suface scaling of concrete. Mixing design was proportioned with the various water-binder ratio between 0.37 and 0.47 and three different binder compositions corresponding to Type Ⅰ cement without any supplementary cementitious materials(OPC), Type Ⅱ cement with 50% blast-furnace slag replacement(BFS50), and ternary cement with Type Ⅲ cement, 15% fly sah, and 35% BFS replacement (BFS 35%+FA 15%). Test results showed that the mixing design with BFS 50% and BFS 35%+FA 15% exhibited higher durability factor than that made with OPC only. Finally, the use of blend cement containing salg can be used effectively in terms of frost durability of the concrete exposed to severe condition like as coastal environment.

with different lengths and different adding ratios, and investigates spalling resistance and residual compressive strength after fire test. Test results should that increase of fiber adding ratio decreased the fluidity of fresh concrete, especially specimens using 19mm of PP fiber and containing combination of simultaneous 12mm and 19mm (Pmxl). For the air content of concrete, all specimens used in this study satisfied the target value. In addition, after fire test, control concrete without fiber exhibited severe spalling, due to abrupt high temperature and vapor pressure of the inside of concrete. However, specimens containing more than of PP fiber and 0.15% of (Psxl) and (Psxl), which is the combinations of 6mm and 19mm as well as 12mm and 19mm of PP fiber respectively. For the residual compressive strength of specimens after fire test completed, even specimens that spalling was not found exhibited 20~50% value, due to the crack occurrence of concrete at elevated temperature.

In this study, the experiment was carried out to investigate and analyze the engineering properties of ultra-high strength concrete according to replacement ratio and fineness of blast-furnace slag. The main experimental variables were water/binder ratio 23.5 27.5, 31.5, 35.5, 39.5(%) water content 165㎏/㎥ and mineral admixtures such as blast furnace slag powder. Even in a case where the ratio of blast furnace slag powder is 70%, using a fineness of 8000 grade afforded a higher strength development than using a plain concrete, which indicates the potential of high utilization in the future. Although it has been pointed out that the concrete using blast furnace slag powder has a problem of yielding relatively low rate of strength development in the early age, it is demonstrated that this can be resolved by using a powder with fineness greater than 6000 grade. It is considered necessary that powder fineness should be upgraded for the applications such as high performance concrete to be used in high strength required areas by considering hydration heat control and early strength requirements in the future.

The purpose of this study is to set mixing rate as activated absorbent replacement rate changes to develop water tank and water road which enable the quality of water to be improved, and to find way to use environment friendly concrete by analysing physical characteristics of concrete, and as a result, characteristics of fresh concrete are decreased as activated carbon replacement rate is increased and bleeding quantity is increased as replacement rate is increased. For hardening concrete, compressive strength, tensile strength and length changing rate are increased as activated carbon absorbent replacement rate is decreased, and water tight shows the increasing trend as replacement rate is increased.

In the past man usually had worked during day, but these days man works for 24 hours. So exterior illumination have become more important in the city life. Lights in the night have extended man's scope of activity, have increased man's productivity and have made good image of city. But indiscreet exterior illumination have made light pollution. It would be meaningful work to study the point at light pollution and search solution of it. This study based on researching on the actual condition of main streets in Busan would be useful to plan light design on light pollution and set a standard of light pollution.

As the modern city grows larger and larger, overpopulated and over-storied apartments caused violation of its sunlight, view and privacy that became social problems. Especially when after the tower-type block have shown up and the formal type of apartment which is plate-type block had been disappearing ever since. Because of this phenomenon, higher and overcrowded apartment became very common and it even made an apartment which made all the block as tower-type block. As the time goes by, it is very easy to see one person pressing charges against another for his or her right to sunshine nowadays. In this study, we will use Auto-CAD to analyze the sunlight environment of tower-type block apartment for its expected harmful element of sunlight. And we will use this data to present basic data of how sunlight environments effect on buildings when it is being designed as apartment.

ventilation system. An inappropriate selection of fan due to incorrect prediction of pressure loss in duct brings energy loss. In the previous study the pressure loss of general spiral duct was measured and database was constructed for finding correct loss factors in fitting upper stream. The purpose of this study is to compare and investigate the error range of flow rate by applying T-Method to bilateral symmetry and asymmetry layout of duct. The results of this study are as following. It is demanded to decide accurate size under duct design for house ventilation system. Because the small amount of Flow rate was considered at that time. The error range was 3.17% on case1 and 3.52% on case2. The error range difference was 0.35%.

Toxic chemical substances as Formaldehyde(HCHO) and Volatile Organic Compound(VOCs) came from high air-tightening for energy saving and indoor building materials has been causing a trouble such as making negative influenza to the resident's respiratory system or causing unbalanced human bodies. Therefore, it established new regulation of ventilator installation standards that secures comfortable & safety Indoor Air Quality(IAQ) which discharges the indoor toxic chemical substances more quickly. In this study, we will research to grope the efficiency enlargement plan by comparing & analyzing the efficiency that comes out from material differences of element core spacer. The result of this study was as follows ; (1) Leak amount came out was 10% rate that correspond JIS research standard. (2) It is needed to decide the right spacer for element core by finding the best fit point in relation of efficiency and intensity dependent of spacer's CaCl2 content to design most suitable element core. (3) Pressure losses became increased during increments of passing airflow, and pressure loss got enlarged because the thick A-Type spacer made more smaller air gap which lets air thorough.

The phenomenon due to the abundance of material civilization and the destruct of environment provoke the damage to the order of nature in the earth. Breathing walls provide a practical and viable technology that enables provision of high quality indoor environments, uses less energy, and combats urban in their construction, and how they can be integrated in environmentally responsive buildings. The latest research findings into life-long particulate and bio-filtration will also be outlined. Design and construction of maintenance-free, modular breathing wall cladding panels and their implementation in actual building projects is briefly described. Forward, our KIER will study about U-value, ventilation and HEPA filter of the BW with the present equipment. If the job is well done, buildings can have a profound beneficial effect on the health, happiness and productivity of those who live and work in them.

On-off differential controller is one of the very important component which has influence on the system performance of the large-scale active solar thermal system. In this study, it was analysed the influence of "on-off" setting temperature on the system efficiency and the electrical consumption by circulation pump. This study was performed by computer simulation using TRNSYS program. The simulation system was developed in this study was verified the its reliability by the experimental results.