Recently, as architectural concrete structures become high-rise and megastructured, concrete become high-strengthened and, by ensuring products of more stability, and rationalization of construction are required.large cross-sectional precast concrete members such as columns show large temperature increase in manufacturing process not only by external heating but also by concrete itself's hydration heating. Therefore, it is expected that specimen for management to predict strength and compression strength of precast concrete member shows different strength characteristics. Conceming this, in order to suggest strength characteristics of high strength mass concrete suitable for precast concrete application, this study comprises the inclusive investigations on the relations between core strength and the strength characteristics per member cross-section dimensional value and per water-bonding material ratio value.

As architectures have recently become high-risers and mega-structured, stable high strength products have been ensured. Accordingly, use of precast concrete accouplement has been increased in order to facilitate air compression and rationalize construction. Since external rising by the steam heating and internal rising by the accumulation of cement hydration heat for the temperature of members, precast concrete members with large cross-section used for high-rise mega-structure's columns and beams may exhibit different temperature history compared to the precast concrete members for wall and sub-floor with relatively small cross-sections. Therefore, this study aims to elucidate the characteristics of temperature history of mass concrete members cast with high-strength concrete for precast concrete application. In this study, large cross-sectional precast concrete mock-up, unit cement quantity, and temperature histories in manufacturing precast concrete member under different curing condition were inclusively investigated.

A prediction of construction cost in preparation for construction document is calculated in compliance with the unit cost in Public construction of korea. This eventually means that the reasonable construction cost of a building can't be determined before construction document phase cost of construction is settled and that the cost of construction is calculated inefficiently because of connection failing between cost management of detailed estimation and information. To improve those problems, therefore, Cost estimating model of structural building elements with approximate quantity survey method is suggested in this research. The model predict the amount of materials and the cost of construction on the basis of historical similar cases. In the direction of data analysis of this research, ratio statistics value is put to practical use to fit into the peculiarities of approximate estimate of each work trade on the basis of actual data amount of materials of historical cases. In addition, the construction phase is connected through the result of a approximate estimate sorted by elements, details work trade.

For new construction, recently, it has expended from physical performance standard to completed apartment' blemish warranty and countermeasure strategy contents. And considering element technology is increasing remodeling’ easiness for deciding operation right or wrong the aged apartment’ re-construction or remodeling. In addition, international standardization of building performance makes rapid progress the point of ISO. In Japan, study of housing commission will be done on a national level for the long commission metropolitan gathering house construction and reproduction technical development, and, already, involving study of approval system of building element made progress. It set the goal performance log index of remodeling’ easiness, it set up component element between a part and public standard type in remodeling. In plan and design phase, it is a precondition that make the performance on the basis of user demand in the whole of Use, maintenance, repair, waste and reuse. Therefore, in the building technology case that development of element technology and practical use are fast in progress, a user is required to evaluate/choice according to performance. And a developer is required to the technical development that aim performance is cleared. The study selected a detailed item about performance item of re-modeling element technique through the requirement which the nations (such as America, England, Japan, etc) and the agencies of foreign countries present and item selection standard, from the point of view where the interest not only the individual but also govemmental politic viewpoint is coming to be higher re-modelling than new construction.

The purpose of this study is to verify the transfer function of input acceleration and output control force based on linearizing a damping term of Tuned Liquid Column Damper(TLCD) with nonlinearity analytically. In addition, analysis is conducted for dynamic characteristics according to the design parameter such as section ratio of both vertical and horizontal column and the level of liquid in the vertical column which is used for tuning method. The dynamic characteristics is identified by the analysis for the natural frequency, damping ratio and effective mass ratio of TLCD and a shaking table test for the transfer function. The results indicates that the level of liquid and section ratio affect the characteristics of damping ratio and mass ratio. Damping and mass ratio increase as the section of vertical column of TLCD decreases due to turbulence in the elbow of TLCD.

The objective of this study is to investigate design parameters of a tuned liquid column damper(TLCD), which is affected by various excitation amplitudes, through shaking table test. Design parameters of a TLCD are examined based on the equivalent tuned mass damper(TMD) model of a TLCD, in which the nonlinear damping of a TLCD is transposed to equivalent viscous damping. Shaking table test is carried out for a TLCD specimen subjected to harmonic waves with various amplitudes. Transfer functions are ratios of liquid displacement of TLCD and control force produced by a TLCD, respectively, with respect to the acceleration excited by a shaking table. They are derived based on the equivalent TMD model of a TLCD. Then, the variation of design parameters according to the excitation amplitude is examined by comparing analytical transfer functions with experimental ones. Finally, the dissipation energy due to the damping of a TLCD, which is experimentally observed from the shaking table test, is examined according to the excitation amplitude. Comparisons between test results and analytical transfer functions showed that natural frequencies of TLCD and the ratio of the liquid mass in a horizontal column to the total liquid mass does not depend on the excitation amplitude, while the damping ratio of a TLCD increases with larger excitation amplitudes.

Modular construction uses pre-fabricated volumetric units that are transported and installed on site as fitted-out and serviced 'building blocks'. The use of modular construction is directly influenced by the client's requirements for speed of construction, quality, reuse and benefits of economy. These benefits may be maximized under the condition that modules are almost manufactured in factory and transported to the site without any damages. In Korea, some damaged modules were reported on the process of transportation. This paper quantifies the vibration performances of modular units under transportation by analytical and experimental methods. Quantified vibration performances are reflected to the transportation guide of modular units.

Basic creep in concrete at an early age plays an important role in the mechancal properties of young concrete and many researches on this field have been carried out. According to recent some studies, however, it is the conclusion that for some cases the basic creep measured from the sealed concrete specimen shows inaccurate results. More specifically, for high-strength concrete (HSC), the incorrectness is more apparent due to autogenous shrinkage occurred at an early age. This paper shows the results obtained from experimental study to evaluate the effect of autogenous shrinkage on basic creep. In this study, four different mixture proportions of which primany test variable is water-cement ratio (w/c) were placed and autogenous shrinkage and basic creep tests on the specimen were performed with age and various loading levels. From this research, it was found that the differences between apparent creep and real creep were remarkable in HSC at an early age. Therefore, it is recommended to modify existing basic creep model equation by considering autogenous shrinkage.

Link slabs designed for macroscopically crack free concrete bridge decks system were experimentally tested. The property requirements of the link slab material were considered. Special focus was placed on the fatigue and durability performance. Introduction of a ductile Engineered Cementitious Composite (ECC) material is proposed for its ability to control crack width and to exhlbit high ductile behavior, which are main performance requirements in the link slab. Experimental results of cyclic tests of full-scale ECC link slabs are compared with those of an ordinary reinforced concrete link slab. The fatigue response will be discussed with particular emphasis on the development of crack widths, which is important for durability against steel reinforcement corrosion The significant enhancement of crack width control in ECC link slab suggest that the use of ECC material can be effective in extending the service life of repaired bridge decks system.