The spinnabiliy of polyvinylidene fluoride (PVDF)/CaCO3 microparticle dope solution were explored via a thermally induced phase separation process, and composite hollow fiber (CHF) membranes were prepared successfully. The experiment results showed that the self‐supporting property of CHF got improved after adding CaCO3 at low concentration of PVDF, so the control of spinning process became easy. The effects of CaCO3 on the structure and properties of hollow fiber membrane were investigated in terms of morphology, water flux, porosity, breakage strength, and crystallization. The results indicated that CHF presented a uniform bicontinuous structure. The permeability and porosity of CHF increased obviously when CaCO3 was removed by acid, while the breakage strength decreased slightly. CHF presented a good drying stability. POLYM. COMPOS., 34:1204–1210, 2013. © 2013 Society of Plastics Engineers

Protein fibers are attractive topics in the past decades. Among them, soybean protein fiber, the regenerated protein-base fiber, is very popular due to its luster, smooth surface, breathability, and comfort. In order to blend with wool and reach union dyeing, soybean protein fiber was first bleached due to its yellow appearance. Various bleaching processes were introduced in this paper. Reactive dyes for cellulose and for wool, such as Unisol or Megafix dyes, together with proper dyeing process were selected and compared. The results showed that one-time oxidation bleaching is confirmed as the bleaching process due to its compromise of high whiteness and bursting strength. It is unable to reach union dyeing for soybean protein fiber/wool fiber with Unisol or Megafix dyes respectively while it is feasible to reach union dyeing of soybean protein fiber/wool fiber dyeing with Unisol dyes followed by Megafix dyes.

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Recycling of reclaimed asphalt pavement (RAP) has gradually emerged as a hot topic in the current research of building materials. Manufacturing the recycled asphalt mixture with a high RAP content still remains a major challenge due to the problem of inferior water damage resistance and fatigue cracking resistance. The aim of this study is to evaluate the servicing performance of recycled asphalt mixture with high percentage of RAP and assess its environmental impact on volatile organic compounds (VOCs) emission. To further explore the intrinsic factor on the performance of a recycled asphalt mixture, the mixed asphalt binder with a different content of extracted RAP binder was firstly investigated. The results show that the larger the content of RAP binder, the lower the mechanical indexes and VOCs emission. There exists an internal relationship between the chemical composition and VOCs release behavior with the variation of the recycled asphalt binder content. Based on the results of mixed recycled asphalt binder, the road servicing performance of a rather high utilization of RAP (i.e., 50%, 60%, and 70%) was assessed. It was found that the reuse of RAP aggregates has little influence on the volume performance of recycled asphalt mixture, and servicing performances still meet the construction requirements in spite of a descending trend. Moreover, a significant reduction effect on VOCs emission was found in the mixing stage of recycled asphalt mixture, indicating that the VOCs emission can be decreased by 94.82% when the content of RAP aggregates increases to 70%. The recycling of RAP with a high content contributes to the sustainable development of road engineering and the construction of green pavements.

In order to study the influencing factors of floor deformation and floor heave mechanisms of deep mining roadways, this paper takes the deep dynamic pressure mining roadway of a mine as the engineering background and adopts a research method combining theoretical analyses, numerical simulations and field observations to study the influence of various factors on floor deformation and floor heave mechanisms. It is determined that the influencing factors on floor heave are a large buried depth, a long duration of dynamic pressure, unique characteristics of the surrounding rock and an insufficient support strength. A bearing mechanics model of the roadway floor beam is established, and it is determined that the displacement of the roadway floor is negatively correlated with the elastic modulus and floor thickness and positively correlated with the buried depth of roadway, the roadway width and the width of fracture zone. A numerical simulation method is used to study the influence of the original geological conditions, strengthening the elastic modulus of floor, strengthening the strength of the side wall rock and increasing the thickness of the floor rock on the displacement of the roadway floor. It is determined that increasing the thickness of floor rock controls the floor heave the most, followed by strengthening the elastic modulus of the floor rock and then strengthening the strength of the side walls. The results of the numerical simulation agree well with those of the theoretical analysis. After the control method of “bottom lifting + bottom angle bolt + floor bolt “ is adopted on site to treat the floor heave, the floor heave volume of the roadway is small during the service period of the 303 working face return air roadway, which meets the application requirements of the roadway. Meanwhile, the theoretical analysis and numerical simulation results are indirectly verified.