Research On Creep Resistance Of Wood Plastic Composites And Its Multi-channel Detection Systems

In this paper, the research concentrates on two aspects of creep resistance of WPC and WPC multichannel creep detection system.Wood-plastic Composites (WPC), as a new kind of composite material, is booming at home and abroad in recent years, which is widely used. However, because the disadvantages of wood creep composites limits its application in the construction field, improving its properties to resist creep is one of the key directions of wood-plastic composite materials research. In this paper, since the plastic can be filled with modified technology, we add carbon nanotubes in the WPC and design five kinds of hybrid WPC(carbon nanotube content:0,1%,2%,5%,8%). By the mechanical properties testing and simulation methods, we analyzed the mechanical properties of pure wood composites. The results showed that adding carbon nanotubes can effectively enhance the flexural properties of wood-plastic composite materials. When the carbon nanotubes is 2%, the bending strength is the best. The relatively pure WPC increases 36.2%. The more carbon nanotubes there are, the less impact strength WPC there will be. Adding carbon nanotubes can improve creep resistance of WPC. According to simulation and actual test, adding more than 1% to 2% of carbon nanotubes can better improve creep resistance. But adding more than 2% would not achieve the role of enhancing creep resistance.In the process of Creep WPC development research, in order to overcome the problem of widely dispersing data, we must launch a large number of samples for testing. However, the current detecting device creep properties belong to single sample detectors, thus carrying out a persistent creep detection will cost a lot of time. In this paper, for the problem of long-time spending and low efficiency of the wood-plastic composites (WPC) creep detection, using virtual instrument technology, we combined the data acquisition system and the traditional mechanical creep detector and designed a multi-channel creep detection system. Firstly according to the principles overall system design, including system software and hardware, creep detection system will be proposed, including hardware and software. The hardware part of the system has Advantech PCI-1710HG data acquisition card as its hardware core and uses HK-KTC-175 rod linear displacement sensors, self-loading device, PCLD-1870 terminal boards to set up the hardware platform; software part of the system which has LabVIEW as its development platform, through the preparation of multi-channel data acquisition program, has firstly realized functions of the 3 channels (extended to 16 channel) data acquisition and control, processing, display and storage. Comparing the system testing with the RD-20D electronic creep cytometry, we testified the feasibility of the system. Three channels (expandable to 16 channels) creep properties detection is viable. What’s more, the direct measure and the simple operation will greatly improve the efficiency of detection of creep.