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The Research of BIM in the Design Stage of Precast Concrete Structures
Li Xinsheng,
Zheng Qizhen,
Li Zhenhua,
Wu Lufang,
Yuan Yungang,
Chen Gang
Issue:
Volume 5, Issue 1, February 2020
Pages:
1-8
Received:
19 December 2019
Accepted:
27 December 2019
Published:
8 January 2020
Abstract: This paper presents a study on the application of BIM (Building Information Modeling) technology based on CDM (Component Data Model) theory in the design stage of precast concrete structures from three aspects of standard formulation, designing by filling numbers and software development, which is used to solve the problem that IFC（Industry Foundation Classes) cannot be implemented in the traditional mode. BIM technology, with its advantages of visualization, parameterization and integration, is widely used in the full life-cycle of prefabricated buildings. Initially, this paper analyzes the disadvantages of traditional BIM technology based on IFC format, such as the defect in developing IFC plug-ins and low data interaction efficiency for the lost of a large amount of data in the model. Then the process of BIM technology based on CDM theory is introduced for the design stage of precast concrete structures and from the comparative analysis of CDM theory and IFC theory, we can find that CDM theory can break the data island in the process of project design and improve the efficiency of data interaction among each BIM software. Finally, the feasibility of the proposed technical route is verified by a practical prefabricated engineering case, and this method can be universally applied to the full life-cycle management of the project construction.
Abstract: This paper presents a study on the application of BIM (Building Information Modeling) technology based on CDM (Component Data Model) theory in the design stage of precast concrete structures from three aspects of standard formulation, designing by filling numbers and software development, which is used to solve the problem that IFC（Industry Foundat...
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The Acoustic Emission Testing Technology on Large Crane Structure Damage
Issue:
Volume 5, Issue 1, February 2020
Pages:
9-14
Received:
13 January 2020
Accepted:
27 January 2020
Published:
13 February 2020
Abstract: The Acoustic Emission testing application on Crane steel structure is greatly limited, because of the factors such as the random transmission path of sound wave, the influence of dynamic load noise and the discontinuity of structure. In this paper, the feasibility of Acoustic Emission detection for crane structure damage is discussed from two aspects: mechanism test and field detection. Based on the analysis of the whole test process, when lifting heavy objects and braking, the metal structure is subjected to the instantaneous gravity load of tens of tons, so that a large number of AE signals are collected by various monitoring sensors. It mainly includes active defect damage, mechanical vibration, structural friction and electrical noise, etc. At this time, the effective defect expansion signal is compared with the noise signal. However, in the load maintenance phase, the noise signal disappears or drops to a very low level. At this point, if a sensor still collects a strong active AE signal, it is highly likely that there is a damage source in this area. Compared with the traditional mechanical properties of materials, AE characteristic parameters, such as amplitude, ringing count and energy count, can reflect the microscopic damage changes of materials under load in a more detailed way. By summing up the distribution range of AE parameters corresponding to different damage mechanisms and typical signal characteristics, such as the "double peaks" phenomenon in the material yield stage, it can provide a scientific foundation for the application of AET in the metal structure damage of large lifting machinery.
Abstract: The Acoustic Emission testing application on Crane steel structure is greatly limited, because of the factors such as the random transmission path of sound wave, the influence of dynamic load noise and the discontinuity of structure. In this paper, the feasibility of Acoustic Emission detection for crane structure damage is discussed from two aspec...
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Safety Study on Blasting Vibration of Down Tunnel in Neighboring Villages
Chunchao Chen,
Zhiyu Zhang,
Zihao Tao,
Jiguo Zhou,
Bishu Zhang
Issue:
Volume 5, Issue 1, February 2020
Pages:
15-21
Received:
13 January 2020
Accepted:
3 February 2020
Published:
13 February 2020
Abstract: Blasting is an effective methods of tunnel excavation, but blasting vibration damage will occur in the construction process. In order to study the blasting vibration of the downlink tunnel, the blasting vibration of the upper part of a tunnel in yunnan was monitored The results show that the vertical vibration velocity is higher than the other two axial vibration velocity, and there is obvious elevation amplification effect in the blasting vibration propagation process. In this test condition, the impact range of blasting vibration is 22m, which will not affect the village. According to HHT analysis, the blasting vibration energy is mainly concentrated in the low-frequency interval, while the high frequency interval vibration energy is small; The instantaneous response spectrum of blasting vibration energy can reflect the number of detonators used for the maximum single-end charge, and there is a surge of energy in the process of blasting vibration energy transmission. At the same time, the expansion of the air face can effectively reduce the transfer of blasting vibration energy. The results show that the propagation of blasting vibration energy can be effectively controlled by controlling the maximum charge of explosive and increasing the blank surface.
Abstract: Blasting is an effective methods of tunnel excavation, but blasting vibration damage will occur in the construction process. In order to study the blasting vibration of the downlink tunnel, the blasting vibration of the upper part of a tunnel in yunnan was monitored The results show that the vertical vibration velocity is higher than the other two ...
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Analysis of the Power Plant Breakwater Failure Subjected to Typhoon Mangkhut Based on Model Experiment
Qie Lu-wen,
Wang Chao,
Luan Ying-ni,
Chen Song-gui,
Chen Han-bao
Issue:
Volume 5, Issue 1, February 2020
Pages:
22-27
Received:
6 January 2020
Accepted:
12 February 2020
Published:
25 February 2020
Abstract: Growing social concern regarding the environmental and visual impacts associated with coastal structures due to climatic change is leading to a reduction in breakwater failures. After Typhoon Mangkhut passed through the southeastern coast of China on September 16 in 2018, the breakwater of a Power Plant was serious failure. As a case study based on model test, the failure process and causes of breakwater were explored in this paper. The wave height and water level were used as the wave parameters, which were accurately extracted by the GOHS system when the typhoon transits, and the breakwater failure process was reproduced based on the typhoon wave forces action at that time. By the experimental result investigating, it was found that the joint of the caisson breakwater and the mound breakwater was firstly failure, then the armor blocks and stones near the seawalls became to be unstable, the seawall was collapsed finally. Based on the analysis of the experiment, the distribution in time and space of the damage of the protective blocks are obtained and divided into different damage areas according to the degree of failure. The wave energy concentration as a important factor were proposed in this paper and the conclusion would be provide as a reference for the study of breakwater engineering.
Abstract: Growing social concern regarding the environmental and visual impacts associated with coastal structures due to climatic change is leading to a reduction in breakwater failures. After Typhoon Mangkhut passed through the southeastern coast of China on September 16 in 2018, the breakwater of a Power Plant was serious failure. As a case study based on...
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Modification and Construction of Solar Cooker Using Parabolic Reflector
Mathew Ayoade Adedeji,
Christopher Kingsley Umunnakwe,
Adedayo Joseph Adesigbin,
Monsuru Olukayode Amoo
Issue:
Volume 5, Issue 1, February 2020
Pages:
28-33
Received:
13 July 2019
Accepted:
6 August 2019
Published:
2 March 2020
Abstract: Energy is essential to economic and social development and improved quality of life of human being. A parabolic solar cooker was modified, fabricated and evaluated as a simple device to harness direct sun rays for cooking purposes. This device was constructed on a steel dish which was completely lined with aluminium foil. This reflecting surface was used to concentrate the rays of the sun at a focus which led to production of high temperature for cooking purposes. A cooking pot stand was erected and positioned near the focus. The equipment was tested for temperature (energy concentration) achieved at the bottom of the cooking pot, and by cooking with it. The energy concentration efficiency of the cooker was found to be 53.41%. The average temperature achieved by this cooker during the time of testing was 107.38°C (380.53K) it was also used to cook beans and groundnuts in comparison to other alternatives such as kerosene stove and firewood. It took one hour to cook beans and 18 mins to boil groundnut. On the other hand, it took 33 mins and 40 mins to cook the same quantity of beans using kerosene stove and firewood, respectively while it took 10 mins and 17 mins to cook groundnuts using kerosene stove and firewood, respectively.
Abstract: Energy is essential to economic and social development and improved quality of life of human being. A parabolic solar cooker was modified, fabricated and evaluated as a simple device to harness direct sun rays for cooking purposes. This device was constructed on a steel dish which was completely lined with aluminium foil. This reflecting surface wa...
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