• Korean Journal of Construction Engineering and Management
• /
• v.23 no.6
• /
• pp.89-100
• /
• 2022

The development of the Construction Production Rates System for appropriate construction cost calculation has recently come to the fore as a means of invigorating OSC based PC structure which currently needs institutional frameworks. PC structure based construction expenses consist of the factory-built assembly, transportation and on-site installation. Recently, in the field of transportation and site installation, research on product structure development is being conducted, such as presenting the standard product calculation system reflecting the results of field survey for each subsidiary materials (Lee et al., 2021). On the other hand, there is no ongoing research on estimating construction expenses of Factory-built assembly. This study suggests Construction Production Rates System which can be used for PC subsidiary materials based Factory-built assembly cost estimations. For the research, work types for the construction procedures have been categorized, and the standard input manpower suitable for the corresponding work characteristics has been derived from analyzing the associated Construction Standard Production Rates for each work type. Also, as the research referred PC subsidiary materials (such as columns, beams, walls, and slab, as well as on-site installation) and the standard number of workforce based on work types, one can calculate direct labor cost, using what the research shows. In addition, it suggests that the size of individual subsidiary materials be the extra cost factor, by using the characteristics that productivity changes depending on the size(m³) of subsidiary materials. It is expected that the research can contribute to objectively verifying factory-built assembly cost through of PC structure, which currently relies on estimates.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2023.05a
• /
• pp.77-78
• /
• 2023

As large logistics buildings have high floor heights and long spans, these buildings are designed as PC structures, and large cranes are used to lift PC members. PC erection planning can generally cause errors depending on the field engineer's experience. To solve this problem, a basic analysis method is needed to establish a systematic PC member erection plan. Crane work can be minimized if the trajectory is easily and quickly calculated according to the location of the crane and applied to the site. Therefore, the objective of this study is a basic study of crane trajectory distance calculation for sustainable PC members erection of large logistic building. In this study, a crawler crane commonly used for lifting PC members is limited. The trajectory distance for the PC erection plan was automatically calculated using the algorithm.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2013.05a
• /
• pp.176-177
• /
• 2013

The composite PC rahmen structure, called Green Frame, allows the main structural members such as PC column and beam to be produced on the site, resulting in a reduction of PC member transportation cost and the margin of PC plant (operation cost and profit), making it more economic than the bearing wall structure. To apply the Green Frame to practice, not only installation but also insitu-production process should be considered. Therefore, this study analyse the influence factors on insitu-production and installation schedule of composite precast concrete members. The results shall be used as basic criteria on the planning of insitu-production and installation of Green Frame.

• Korean Journal of Construction Engineering and Management
• /
• v.13 no.3
• /
• pp.34-42
• /
• 2012

Green frame technology intended to facilitate the remodeling of apartment housing complexes in Korea and extend their service life has been developed. Green frame design is a Rahmen structure using composite precast concrete members and, unlike a bearing-wall structure, lifting and installing structural members accounts for major steps of structural construction. Therefore, if green frame structure construction is to be scheduled appropriately, systematic lifting plan needs to be developed in advance. Development of lifting plan also requires unit lifting process of composite PC members (columns and beams) that consist of green frame to be analyzed first. Therefore, this study attempts to analyze the lifting process of composite PC members used in green frame structure. To that end, lifting procedure and time of composite PC column and beam are estimated and applied to a project case to analyze the lifting cycle of reference floor. Outcomes produced herein will be used as key data for development of lifting plan in subsequent green frame structure construction.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2021.11a
• /
• pp.90-91
• /
• 2021

Large logistics centers are being built around the world. Most of these buildings have characteristics of long span and heavy load, and use PC (precast concrete) structure for quick construction. There have been few attempts to systematically analyze the various influencing factors of PC erection planning. In this study, we intend to analyze the influencing factors necessary for the creation of a sustainable PC erection planning algorithm.

• Korean Journal of Construction Engineering and Management
• /
• v.22 no.6
• /
• pp.96-106
• /
• 2021

The PC structure based on the OSC (Off-Site Construction) is mentioned as a representative method of innovation in the construction industry that converts the existing construction environment from site-centered to factory production-transportation-site assembly. However, recent research on PC method has focused on improving the functions of subsidiary materials and improving the production system to increase productivity and institutional / policy R&D that can be universally applied to the life-cycle stage of ordering / design /construction is insufficient. In particular, the absence of standardized cost calculation standards makes it difficult to calculate and verify of objectified appropriate construction cost. So which is an obstacle to the activation of the PC method. In this study, the standards for construction costs of domestic and foreign PC method were surveyed and similar Construction Standard Production Rates were analyzed to confirm the product structure suitable for PC method. Subsequently, the construction procedures and input resources for each PC subsidiary materials were identified through on-site surveys to derive component for subsidiary materials, and the factors of change in the product according to the construction characteristics(height, weight of subsidiary material) were verified. As a result the standard product calculation system suitable for the site installation of the PC method for apartment was presented.

• Korean Journal of Construction Engineering and Management
• /
• v.25 no.2
• /
• pp.56-68
• /
• 2024

A construction standard production rates system for the factory built and on-site installation phases of OSC (Off-Site Construction)-based precast concrete (PC) structures in apartment buildings was recently proposed to establish an objective cost standard (Lee et al., 2021). In addition, the Korean government has taken steps to improve the institutional foundation for the systematic calculation of PC construction costs such as revising construction standard production rates for major components that can be applied to the on-site installation phase of PC method. In this study, we analyzed the results of a field survey of apartment building PC structures and collected expert opinions to develop factory-built and on-site installation standard production rates that can be applied to apartment building PC method. We also propose directions for improving the standard production rates so that they can be applied to the site and component of apartment buildings by comparing them with the current standard production rates. This study also derived the cost characteristics and cost reduction measures of PC construction by calculating the construction costs using the developed rates and comparing the construction costs with the RC methods of apartment buildings of the same scale. The construction standard production rates for PC construction derived in this study are expected to contribute to the spread of PC construction by ensuring the objectivity and consistency of the results of PC methods cost estimation.

• Journal of the Korea Institute of Building Construction
• /
• v.22 no.5
• /
• pp.519-530
• /
• 2022

As online commerce increases, the construction of large logistics buildings worldwide is exploding. Most of these buildings have the characteristics of long span and heavy loaded and use precast concrete components, a pin joint structure, for rapid construction. However, due to construction safety and structural stability requirements, the pin joint structure has many limitations in terms of the erection of the PC member, which increases the time and cost. A structural frame connected with steel joints between precast concrete components, called a SMART frame, has been developed, which addresses these constraints and risks. However, the effect of the appllication of a SMART frame on the time aspect has not been analysed. The study is a time reduction effect analysis of a SMART frame for long span and heavy loaded logistics buildings. For this study, the authors select a case site erected using existing PC components, and compare the time reduction with the SMART frame erection simulations. Through this analysis, it was found that a time reduciton about 4 months, approximately 48% of the conventional PC installation period could be achieved. If the SMART frame is applied when carrying out future large-scale logistics building projects, it can be expected to have the effect of significantly shortening the construction period compared to the conventional method.

• Journal of the Society of Disaster Information
• /
• v.14 no.4
• /
• pp.492-500
• /
• 2018

Purpose: In this paper, based on this background, the main purpose of studying the behavior of concrete slab reinforced with new material fiber in impact loading is investigated by AFRP using aluminum fiber. Results: Research on the use of new materials as reinforcing materials for concrete members has been carried out in many fields such as flexural and shear tests under static loading, fatigue loading under cyclic loading, and application to PC beams. However, And the issue of plate elements is still at a basic stage. Conclusion: In this paper, the dynamic behavior of reinforced concrete slabs is investigated by using AFRP rod reinforced with aluminum fiber.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.248-248
• /
• 2000

본 연구는 조선 소조립, 판넬조립 등의 공정에서 발생되는 필렛 용접 부위의 용접 자동화를 위한 로봇 시스템 개발에 관한 연구이다. 조선등의 중공업 분야에서는 작업이 중량이고 대형임에 따라 로봇이 부재의 특정위치로 이동하여 작업해야 한다. 또한 작업대상의 형상이나 치수가 매번 변경됨에 따라 이에 능동적으로 대처할 수 있어야 한다. 본 연구에서는 두 대의 로봇(2대x6축=12축)이 다축 문형 캔트리(4축)에 장착된 조선용 필렛용접 로봇 시스템(16축)을 개발하였다. 필렛용접부재를 중심으로 두 대의 로봇이 양쪽을 동시에 용접하는 방식으로 고속회전토치를 적용하여 위빙동작없이 원하는 용접각장(Leg Length)을 생성할 수 있다. 캔트리 시스템은 PC 기반의 별도 제어기로 구성하여 두 대의 로봇 제어기와 신호 입출력에 의해 동시동작이 가능하도록 하였으며, 작업장에 놓인 부재의 위치오차를 보장하기 위하여 시각센서를 적용하였다. 용접시작점의 위치보정을 위한 시작점 검출을 위해접촉센서(Touch Sensor)를 적용하였으며, 용접선 추적을 위해서 아크센서(Arc Sensor)를 적용하였다. 본 시스템 2000년 1월 제작 설치가 완료되어 현재 성능 테스트가 완료된 상태로 향후 생산현장에 적용될 계획이다.