The two main objectives of this research were (1) to propose a new subgrade soil stabilization protocol to allow CDOT and other transportation agencies to rely upon an alternative stabilization method that is not subject to the typical problems associated with calcium-based stabilization of sulfate-rich soils (the proposed technology is also appropriate to stabilize sulfate-free subgrade soils), and (2) to develop a new database of MEPDG parameters for local soil samples obtained from CDOT and to provide advanced testing and analysis of the stiffness degradation of these materials. The beneficial use of scrap tire rubber mixed with expansive soils is of interest to civil engineering applications since the swell percent and the swell pressure can be potentially reduced with no deleterious effect to the shear strength of the mixture.

关键词：土壤稳定;硫酸盐;公路建设;混合物;橡胶

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The seeder of rice bud-seed for field seedling raising is a new seedling equipment for field seedling raising,which is a complicated vibration system with multi-freedom.And the effect of the vibration parameters and interactions on the vibration velocity at different locations of the moving rail of two electromagnetic vibration metering devices which are installed side by side is large,and the passing rate of seeding is affected.In this paper,the virtual prototype of seeder of rice bud-seed for field seedling raising is established by ANSYS and ADAMS.The virtual prototype is developed to carry out dynamics simulation by using four-factor quadratic regression orthogonal rotary combination design.Mathematical models of influencing factors of vibration and variation coefficient of vibration velocity,and the factors and average velocity of seeding are established.The factors are optimized.And optimal combination of vibration influencing factors and the variation coefficient of vibration velocity interval with 95％ reliability are achieved.The result shows that optimal combination of factors is achieved under the condition that the excitation force amplitude is 39.8N,vibration frequency is 32.7Hz,the velocity is 58.5mm/s,stiffness of vibration isolating rubber pad is 1167N/mm.The corresponding variation coefficient of the vibration velocity is 6.287％,and the average seeding velocity is 18mm/s.The variation coefficient of the vibration velocity interval with 95％ reliability is from 2.909％ to 9.665％.

关键词：水稻;播种机;虚拟样机;振动速度的变异系数;振动参数优化

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The overall goal of this program was to develop a large area updateable 3D color display using unique and innovative photorefractive (PR) polymers with fast writing times (ms), long persistence (hours) and rapid erasure (several seconds). A multi-pronged approach was used to integrate the presently established materials, find new photorefractive materials, and electronics and photonics techniques to achieve the following goals: (1) 3D display devices: we developed large area PR polymer devices for updateable 3D display; (2). Materials optimization: we designed and synthesized a PR polymer with high figures of merit for 3D display applications; (3) Nanosecond pulse recording: recording setups based on a high repetition rate nanosecond pulsed laser to increase the recording speed were developed; (4) Color holograms: A color 3D display system was implemented by angular multiplexing.

关键词：全息光折变材料;彩色摄影;聚合物;三维流

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Numerical simulation of impact events on fabric-based protective systems requires accurate mechanical characterization of the constituent material at similar strain rates as the impact event. Because Kevlar (Kevlar is a registered trademark of DuPont Company) yarn is woven into fabric to make protective equipment, the strength of the individual filaments may become compromised as a result of the crimping, weaving process, or finishing process. To elucidate and quantify any damage to the fibers as a result of the weaving or post treatment finishing process, single fibers were extracted from the warp and weft directions of plain woven, hydrophobically treated Kevlar cloth and the strength was measured over a wide range of strain rates and compared to the response of fibers extracted from an unwoven yarn. The tensile strength of fibers from the warp, weft, and unwoven Kevlar were evaluated at 0.001 s 1, 1 s 1, and approximately 1000 s 1 using a Bose Electroforce test setup and a Hopkinson tension bar modified for fiber experiments. A wide range of gage lengths from 2 to 150 mm was investigated to find the effect of defect distribution on the tensile strength of the single fibers. The results show that fibers taken from the weft direction of the woven fabric decreased in strength 38compared to the unwoven fiber. The warp fibers were a minimum of 20weaker than unwoven and weft fibers at all loading rates. Measured Young s Modulus as a function of strain rate and tensile strength as a function of gage length are also presented in this technical report.

关键词：纤维；负载力；；聚合物；高分子材料

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Laminated Carbon Fiber Reinforced Polymer (CFRP) composites are very effective in weight saving in aeronautical structural components. It is, however, difficult to detect damage such as delamination, matrix cracks, and local fiber breakages caused by low velocity impact loading. In the previous study in 2009, Time Domain Reflectometry (TDR) method was applied to a unidirectional laminated CFRP structure for the first time. In 2010, the research applied the TDR method for the CFRP laminates. In the present study, therefore, actual impact damage is employed instead for the TDR. Electrical contact between fiber fragments exists in these micro-buckling regions although the electrical resistance becomes very high at the micro-buckling point. We have to investigate the applicability of the TDR method for the impact damage. A low speed impact test is performed to a cross-ply CFRP plate, and impact damage is made at the surface of the CFRP plate. TDR is applied to the cross- ply CFRP plate. The result shows that the reflected signal can be observed after the impact test. This result indicates that the TDR method is useful for detection of the low speed impact damages.

关键词：复合材料；纤维增强塑料；屈曲；碳纤维

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The dynamic viscoelastic properties of solution polymerized styrene-butadiene (SSBR) filled with different proportion of carbon black and silica were studied by using the rubber processing analyzer (RPA2000) and DMA under different scanning conditions.The results indicated that in the first strain sweeping process,the storage modulus (G') reduced gradually with the increase of ratio of carbon black,and the function of coupling agent (Si69) decreased.During the secondary strain sweeping process,it was found that with the increase of sweeping time interval,the stress softening phenomenon abates.On the other hand,through three strain sweeping,it was considered that the effect of Payne was not caused only by the factor of filler-net.

关键词：炭黑；二氧化硅；SSBR；动态特性

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The major accomplishments during the tenure of this proposal include: Designed target test patterns of optical grating devices and fabricated e-beam lithography-based master molds. Printed micro and nanostructures using a newly developed spin-on nanoprinting (SNAP) technique. SNAP is a simple and easy technique to print any optical structures. The contractor demonstrated that this technique can be used to print grating structures on a silicon substrate.

关键词：光电子技术；光栅（光谱）；聚合物；铵化合物；脱氧核糖核酸

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A novel fluorophore tagged exopolysaccharide (TEPS) was developed, synthesized, and tested for its potential implications toward locating Improvised Explosive Device (IEDs). Our TEPS exhibited unique and substantial properties that lend well to current change detection processing techniques and allows for significantly improved detection of objects implanted into the natural landscape. When coupled with a novel image processing package, or Automated Disturbance Detection System (ADDS), that automatically processes images, and creates a map of areas of interest (AOIs) that relate to the detection of a hidden object, TEPS has shown great success. For example, in pilot scale field testing it was able to accurately and automatically identify large (larger than 12') implanted devices nearly 100of the time and smaller objects (between 1' and 12') 87.5of the time from an aerial platform. Furthermore, the system only falsely detected one terrestrial disturbance for every fourteen that it correctly identified. An additional benefit of our TEPS system is that its computational requirements will be about 75less than comparable systems because computationally intense preprocessing algorithms are unnecessary. The combined TEPS and ADDS technologies can rapidly produce maps of AOIs, which would ultimately allow for greater and safer movement of troops in dangerous areas.

关键词：变化检测；简易爆炸装置；聚合物；自动化；耦合（互动）

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Military piers in marine environments are typically supported atop steel-reinforced concrete piles that are subject to corrosion and concrete deterioration. The failure of even one pile presents a risk of catastrophic structural failure and interruption of operations. Patching deteriorated concrete does not stop corrosion of the reinforcement and may even accelerate it. An impact and corrosion protection wrap (ICPW) system, incorporating a composite structural wrap and cathodic protection system, was designed to rehabilitate deteriorated steel-reinforced concrete marine piles in service at Kawaihae Harbor, HI. The purpose of the technology is to reduce pier life-cycle costs and downtime by inhibiting corrosion-related damage to steel-reinforced concrete piles. The ICPW system consists of a composite reinforced polymeric wrap with an integrated galvanic anode to provide protection in the tidal splash zone. Corrosion activity in 20 rehabilitated piles on two piers was monitored using reference electrodes and data loggers. Results of the demonstration indicate that the system can protect and extend the life of in- service reinforced concrete structural piles in a corrosive marine environment. An economic analysis determined that full implementation of the system on all piles of the two demonstration piers would provide 3.16 return on investment.

关键词：阴极保护；腐蚀；聚合物；钢筋混凝土；高分子材料

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Fiber-reinforced polymer matrix composite materials display quite complex deformation and failure behavior under ballistic/blast impact loading conditions. This complexity is generally attributed to a number of factors such as (a) hierarchical/multi-length scale architecture of the material microstructure; (b) nonlinear, rate-dependent and often pressure-sensitive mechanical response; and (c) the interplay of various intrinsic phenomena and processes such as fiber twisting, interfiber friction/sliding, etc. Material models currently employed in the computational engineering analyses of ballistic/blast impact protective structures made of this type of material do not generally include many of the aforementioned aspects of the material dynamic behavior. Consequently, discrepancies are often observed between computational predictions and their experimental counterparts. To address this problem, the results of an extensive set of molecular-level computational analyses regarding the role of various microstructural/morphological defects on the Kevlar fiber mechanical properties are used to upgrade one of the existing continuum-level material models for fiber-reinforced composites. The results obtained show that the response of the material is significantly affected as a result of the incorporation of microstructural effects both under quasi-static simple mechanical testing condition and under dynamic ballistic-impact conditions.

关键词：纤维增强复合材料;基体材料;力学性能;聚合物;轴向载荷

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