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Zhou C.,Beijing Jiaotong University | Zhou C.,Tongji University | Li J.,China Architecture Design and Research Group | Zhu W.,Liuzhou OVM machinery Co. | Yang F.,Liuzhou OVM machinery Co.
Jianzhu Jiegou Xuebao/Journal of Building Structures | Year: 2013

A new anchorage system-self-locking anchor (SLA) was proposed which can be used to tension and anchor lateral fiber reinforced polymer (FRP) sheets. SLA mainly consists of two anchor heads, bolts, nuts and FRP belts, and it can be divided into the fixed anchors and the movable anchors. According to the needs, it can combine into anchor system for single-layer or double-layer FRP belts. Based on the tests for the working performance of SLA, the fixed anchors without bond glue can provide 20% lateral pre-stressing for carbon fiber reinforced polymer (CFRP) belts and it is suitable for the fast strengthening of concrete columns; the movable anchors with simple technology can provide more than 30% lateral pre-stressing for CFRP belts and is more suitable for practical engineering. According to the test results, the calculating method of the size of anchor head and the length of FRP belts, the method of application and control of pre-stressing for lateral FRP belts by torque wrench and the conversion formula between the torque and the pre-stressing of lateral FRP belts were proposed, and the reliability of this conversion formula was also verified by the test results. Then the mechanism of SLA in the tension process of lateral FRP was analyzed, and the theoretical analysis and experimental results show that the SLA has good reliability and practicality.


Shen Y.,Tongji University | Lu S.,Liuzhou OVM Machinery Co. | Li F.,Tongji University
Advances in Materials Science and Engineering | Year: 2015

Carbon fibre reinforced polymer (CFRP) is currently used to reinforce buildings in civil engineering in the common forms of sheets, while the utilization efficiency of a CFRP materials greatly decreased when the CFRP material is directly bonded to the structure because of the lack of the effect of the exertion of a prestress. A paper spool-inspired anchoring method is proposed to overcome the shearing problem in the anchoring system through the friction between layers. Anchoring and jack-up tensioning devices for CFRP sheets are also designed and produced. A prestress is successfully applied to single and multiple CFRP sheets (80% tensioning strength is achieved), thus verifying the tensioning effect of the prestress. Based on these results, prestressed concrete flat slabs were designed with pretensioned CFRP sheets. The corresponding mechanical properties of the concrete flat slabs are tested to verify the feasibility of using CFRP sheets to apply a prestress. The results show that the uniformity of the fibre stress during the tensioning of the CFRP sheet is the key to the success of the application of the prestress. © 2015 Yin Shen et al.


Li F.,Tongji University | Xie Z.,Liuzhou OVM Machinery Co. | Guo X.,Tongji University
Applied Mechanics and Materials | Year: 2012

When the bridges broaden with seamless technology, there are differences between the existing bridge and the new bridge in design, construction and service. Because of concrete creep and shrinkage, temperature effect and prestress loss, there are stress defects in the seam, which will affect the service and safety. The current methods for the seam in foreign and domestic, such as plant steel and semi-rigid connection method are passive measures based on structure exiting state, which cannot ensure the long-term performance of the seam. © (2012) Trans Tech Publications, Switzerland.


Chen G.,Kunming University of Science and Technology | Wen J.,Liuzhou OVM Machinery Co.
Journal of Mechanical Science and Technology | Year: 2015

Although there are a large number of studies on large rolling bearings, analyses are seldom for the effects of size and raceway hardness on their fatigue life. In this study, taking the four contact-point ball bearings as an example, the fatigue lives of large rolling bearings with different structure sizes were calculated through the stress life (σ-N), strain life (ε-N) and international standard (ISO) methods, respectively. The maximum contact force and subsurface stress in the raceway were obtained with the finite element method. At the same time, the effect of raceway hardening depth on bearing life was taken into account. Results showed that the effect of raceway hardening depth on the life of large rolling bearing was obvious. Thus, the raceway hardening depth cannot be ignored when calculating the fatigue life of large rolling bearing. When used with the load at the same level, the rolling bearing with larger size usually had less the fatigue life. © 2015, The Korean Society of Mechanical Engineers and Springer-Verlag Berlin Heidelberg.


Zhu W.,Harbin Institute of Technology | Zhu W.,Liuzhou OVM Machinery Co. | Li L.,Guilin University of Technology | Deng A.,Liuzhou OVM Machinery Co.
Advanced Materials Research | Year: 2011

Using the electrostatic spraying method to spray the epoxy coating on the surface of prestressing wire or strand. By this method, the mechanical properties can reach the same level of original prestressed steel, the anti-corrosion ability is superior to that of galvanized steel, and the epoxy coating not only does not have a negative impact on anchorage performance, but also improve the bond strength between wire and cold-cast filler. The LZM cable system using epoxy-coated wire and the OVM250 and GJ cable system using epoxy-coated strand have been developed and widely applied in China since the year of 2001.


Zhu W.,Harbin Institute of Technology | Zhu W.,Liuzhou OVM machinery Co. | Qin X.,Liuzhou Road and Bridge Construction Management Office | Huang Y.,Liuzhou OVM machinery Co. | Zhu X.,Guangxi University of Technology
Applied Mechanics and Materials | Year: 2012

This paper presented a new kind of strand cable system, which cable body was composed by the strands isolated by HDPE sheath. The isolation extrusion method were used in anchoring the bundle of strands on the anchorage of both cable ends. The type of the cable-stayed structure, features, test and engineering design and application were described. The result shows that the cable system has compact anchorage structure and small diameter, which can be more stable to reach the correlative standards requirement on static load and fatigue performance. The cable system provides a new choice in the bridge construction and had been widely applied in China since 2005. © (2012) Trans Tech Publications.


Xinyu G.,Tianjin University | Xinyu G.,Liu Zhou OVM Machinery Co. | Gang C.,Guilin University of Electronic Technology | Daoyin Y.,Tianjin University | Zexin X.,Guilin University of Electronic Technology
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2012

A second parallel CCD (CMOS) imaging system for an telescope objective with the fixed D/f' is proposed in detail. As a direct imaging system that the CCD target surface coincides with the imaging surface of the telescope objective, it shows the outstanding performance of more than doubled resolution compared with the ordinary telescope objective under the same D/f'. Based on the discussions about the second parallel optical path telescope system, three design examples are compared and analyzed. The relation between the optical properties of image field and the optical elements of the second parallel path is clarified, which provides an operable method for readers. This practice has proved the outstanding performance of the new telescope objective photoelectronic imaging system which indicates potential applications in broad scientific and industrial prospects. © 2012 SPIE.


Deng N.,Liuzhou OVM Machinery Co. | Liu X.,Liuzhou OVM Machinery Co. | Zhang N.,Hunan Road and Bridge Construction Group Corporation | Wu L.,Liuzhou OVM Machinery Co.
Applied Mechanics and Materials | Year: 2012

Aizhai Bridge is a stiffening steel truss girder suspension bridge and the main bridge consists of three spans of 242m+1176m+116m. It flies over Dehang Canyon, which is cliffy and steep, the depth between the designed elevation and the ground is 355 meters. In order to overcome the problems happened during the transportation, a new construction plan for the erection of steel truss girder is developed, combining the lifting technology with the cable-tracking transportation. Simply speaking, main cables and hangers are used as bearing structure, the track cables hanged on the hangers are used as transportation track. The transport vehicles system run along the tracking cables to deliver the steel truss girder, and the deck unit erecting system do the lifting job. In this paper, the scale model experiment and full scale model test of the track-cable transferring system are introduced, the design and test of erection gantry for deck unit are described. Finally, the engineering application of the track-cable erecting system is described. The results of experiment and engineering application show that the transportation and erection work of steel truss girder can quickly be completed by using the new construction plan. It is safe and economic solution, and has very broad prospect and practical value for the construction of suspension bridge and arch bridge. © (2012) Trans Tech Publications, Switzerland.


Yang B.D.,Guangxi University of Science and Technology | Zhu W.X.,Liuzhou OVM machinery co. | Ju H.C.,Guangxi University of Science and Technology | Zhang F.,Guangxi University of Science and Technology | And 2 more authors.
Applied Mechanics and Materials | Year: 2013

Through the equipped with spiral reinforcement of the prestressed anchorage performance test, verify the spiral reinforcement for anchoring system the function and necessity. And using finite element analysis software of prestressed member was compared and analyzed, analyses the influence of the spiral reinforcement of concrete and the spiral reinforcement stress distribution. © (2013) Trans Tech Publications, Switzerland.


Deng L.,Guangxi University of Technology | Deng L.,Guangxi University | Chen H.,Guangxi University of Technology | Yan L.,Guangxi University | And 3 more authors.
Zhongguo Tiedao Kexue/China Railway Science | Year: 2010

The independently developed carbon fiber reinforced plastics (CFRP) an chorage and tension devices were adopted to carry out tests on the flexural behav ior of 8 model specimens of reinforced concrete beams strengthened with different forms of CFRP plates. Influence of the side-strengthening of the prestressed CFRP plates on the strengthened RC beam was studied, including the carrying capacity of the beams, the deformation and the cracks of the using stage, the concrete compressive strain, the stress distribution of the CFRP plates in the using stage and the ductility. Experimental results show that the side-bonded with the prestressed CFRP strengthening method can obviously increase both the cracking load and the yield load of the flexural members, reduce the deformation and the crack of the member during the using stage. The reliable anchorage at both ends can prevent the debonding failure. At the same time, the ductility performance of the concrete members can be increased by making the most of the material strength.

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