Zn-montmorillonites(Zn-MMTs) as antibacterial compounds were prepared by an ion-exchange reaction. The reaction time, initial pH value and molar ratios of CEC influencing zinc content in Zn-MMTs were investigated, and Zn-MMTs were characterized by means of EDX, XRD, XPS, and SEM. The results of bacterial growth tests were confirmed by determination of the minimum inhibition concentrations (MICs) and minimum bactericidal concentrations (MBCs). The experimental results show that the zinc is confirmed as bivalent zinc state, the d ₀₀₁ basal spacing of Zn-MMTs is enlarged with the enhancement of the zinc content, and the particles of Zn-MMTs are formed with irregular shape. Moreover, the antibacterial activity of Zn-MMTs increases with increasing the zinc content, and Zn-MMT-3 containing 6.76 mass% of zinc exhibits optimum antibacterial activity against Escherichia coli and Staphylococcus aureus. The intercalated zinc ions act as very effective antibacterial substances in the long term.

The effect of ZnO-B₂O₃(ZB) glass addition on the sintering behavior, microstructures and microwave dielectric properties of BaO-Nd₂O₃-TiO₂-Bi₂O₃ (BNTB) system was investigated with the aid of X-ray diffraction, scanning electron microscopy and capacitance meter. It is found that the ZB glass addition, acting as a sintering aid, can effectively lower the sintering temperature of BNTB system to 850 °C. The dielectric constant of BNTB-ZB ceramics increases with the increase of soaking time and the value of dielectric loss decreased with increasing soak time. The optical dielectric properties at 1 GHz of ɛ=74, tan δ=4×10⁻⁴, and TCC=25 ppm/°c were obtained for the BNTB system doped with 25 wt% ZB glass sintered at 850 °C for 2 h, representing that the BNTB-ZB ceramics could be promising for multilayer low temperature co-fired ceramics applications.

Electroless Ni-P/nano-CeO₂ composite coating was prepared in acidic condition, and its microstructure and corrosive property were compared with its CeO₂-free counterpart. Scanning electronic microscopy (SEM), transmission electronic microscopy (TEM) and differential scanning calorimeter (DSC) were used to examine surface morphology and microstructure of the coating. Aqueous corrosion was done in 3%NaCl+5%H₂SO₄ solution and high temperature oxidation was done at 750 °C in air. The results showed that Ni-P coating had partial amorphous structure mixed with nano-crystals, while the Ni-P/CeO₂ coating had perfect amorphous structure. At high temperature, Ni3P precipitation and Ni crystallization took place in both coatings at different temperatures. Aqueous corrosion property and high temperature oxidation property of the composite coating were remarkably improved due to the coating’s microstructure change and the rare earth doping effect. During the co-deposition process, some Ce ⁿ⁺(n=3, 4) ions may be adsorbed to metal/solution interface and hinder nickel deposition. Ni-P/CeO₂ coating’s perfect amorphous structure results from the hindered crystal- typed deposition of nickel and the promoted deposition of phosphorous.

The transparent C-doped TiO₂ nanostructure films were fabricated on the silicate glass substrates by sol-gel spin-coated method. The as-prepared films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible absorption spectra (UV-vis) and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity was evaluated via the photo-catalytic oxidation of methylene blue in aqueous under daylight irradiation at room temperature. The results show that the daylight-induced photocatalytic activities of the as-prepared films are improved by the C-doping. The calcination temperatures significantly affect the morphology, microstructure and photocatalytic activity of the as-prepared samples. At 723 K, the C-doped TiO₂ films exhibit the highest photocatalytic activity due to the synergetic effects of good crystallization, appropriate oxygen vacancies and strong absorption in the near UV and visible-light region.

Neodymium-substituted bismuth titanate (Bi₃NdTi₃O₁₂, BNT) thin films were prepared on quartz substrates by a metal-organic solution deposition process. The crystalline structure was evaluated by X-ray diffraction. Waveguide property was investigated by using prism coupling technique and optical transmittance measurement. The optical nonlinearities of the film were measured by the top-hat Z-scan techniques and a large positive nonlinear refractive index, nonlinear refractive coefficient and two-photon absorption coefficient were determined to be 3.84 × 10⁻⁷ esu, 0.7523 cm²/GW and 4.81 × 10⁴ cm/GW, respectively. These results reveal that the BNT film may be a kind of new multifunctional materials.

Calcium phosphate fiber was synthesized by homogeneous precipitation method using urea as precipitation agent. Effects of the reactant concentration and hydrothermal temperature on the calcium phosphate morphology and composition were studied using SEM, FTIR and XRD. It is found that fine octacalcium phosphate(OCP)fiber can be synthesized when the reactant concentrations are 0.167 mol/L for Ca(NO₃)₂, 0.1 mol/L for (NH₄)₂HPO₄, and 0.6–0.7 mol/L for (NH₂)₂CO, respectively, with the initial reactant solution pH value around 2.2, hydrothermal temperature 90 °C and termination reaction at pH value around 5.0. At very low urea concentration, the product size distribution is highly inhomogeneous, however, at an excessively high concentration the product becomes larger and shorter and a mixture of OCP and hydroxyapatite (HA). Increasing the hydrothermal temperature is favorable to the fast precipitation of OCP, higher productivity and finer product.

ITO thin films were grown on PC(polycarbonate), PMMA(polymethyl methacrylate) and glass substrates by r.f. magnetron sputtering. The electrical, structural and chemical characteristics of ITO films were analyzed by the Hall Technique, X-ray diffraction, and X-ray photoelectron spectroscopy. XPS studies suggest that all the ITO films consist of crystalline and amorphous phases. The degree of crystallinity increases from less than 45% to more than 90% when the substrate temperature increases from 80 to 300 °C.The In and Sn exist in the chemical state of In³⁺ and Sn⁴⁺, respectively, independent of substrate type and temperature. The enrichment of Sn on surface and In in body of ITO films are also revealed. And, the oxygen deficient regions exist both in surface layer and film body. For ITO films deposited under 180 °C, the carrier concentration are mainly provided by oxygen vacancies, and the dominant electron carrier scattering mechanism is grain boundary scattering between the crystal and the amorphous grain. For ITO films deposited over 180 °C, the carrier concentration are provided by tin doping, and the dominant scattering mechanism transforms from grain boundary scattering between the crystal grains to ionized impurity scattering with increasing deposition temperature.

By using inorganic Fe₃O₄ nanoparticles of different content as nucleation sites, PAn-Fe₃O₄ nanorods were successfully synthesized through a simple, conventional, and inexpensive one-step in-situ polymerization method. The TEM images revealed the size and morphology of the resultant nanocomposite. The EDS pattern confirmed the existence of Fe₃O₄ in the composite. The FT-IR spectral analysis confirmed the formation of PAn encapsulated Fe₃O₄ nanocomposite. With the content of Fe₃O₄ increasing, the conductivity of the nanocomposites gradually decreases, meanwhile, the saturation magnetization increases and reveals a super paramagnetic behavior. With controllable electrical, magnetic, and electromagnetic properties, the well-prepared nanocomposites may have the potential applications in chemical sensors, catalysis, microwave absorbing, and electro-magneto-rheological fluids, etc.

Calcined kaolin/TiO₂ composite particle material (CK/TCPM) was prepared with TiO₂ coating on the surfaces of calcined kaolin particles by the mechano-chemical method. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to investigate the microstructures and morphologies, respectively. The mechanism of the mechano-chemical reaction between calcined kaolin and TiO₂ was studied by infrared spectra (IR). The results show that TiO₂ coats evenly on the surfaces of calcined kaolin particles by Si-O-Ti and Al-O-Ti bonds on their interfaces. The hiding power and whiteness of CK/TCPM are 17.12 g/m² and 95.7%, respectively, presenting its similarity to TiO₂ in pigment properties.

Ni-doped ZnO nanopowder (Zn_0.98Ni_0.2O) was synthesized by improved coprecipitation method. The average particle size of the powder was estimated to be 50 nm. The powder was then processed by thermal treatment. Samples were annealed at 1 073, 1 273, and 1 473 K, respectively. The solubility of NiO in ZnO and the lattice parameters of ZnO both increased with the temperature. The magnetic property of the doped samples was examined, and hysteresis loops were got. The results showed all the samples were ferromagnetic, while powder processed at 1 273 K for 4 h got a highest saturation magnetization (M _s) of 0.0457 emu/g. Also, magnetic properties were related to the grain size of the powder.

High molecular weight(Mw) poly(L-lactic acid)s(PLLAs) were synthesized using multifunctional epoxy compound(Joncryl-ADR4370) as chain extender. The products were characterized by gel permeation chromatography(GPC) and spectroscopy(¹HNMR and FTIR). The results indicated that the Mw of PLLA increased with the increasing of the ratio of epoxy compound and the extending of reaction time. The highest M _w of PLLA reached 360 000 g/mol when the ratio of epoxy compound was 1.5 wt%. However, the reactants turned to cross-linking when the ratio of epoxy compound was over 1.5 wt%. Differential scanning calorimetry(DSC) measurements demonstrated that the glass transition(T _g) and melting temperatures(T _m) of products increased slightly as the increase of the molecular weight. Analysis of the hydrolytic degradation in vitro showed that the branched PLLA possessed the quicker degradability than that of the linear PLLA.

Cross-linked polystyrene/glass fiber composites were fabricated using cross-linked polystyrene (CLPS) as matrix and E-glass fiber as the reinforcement. Surfaces of E-glass fibers were modified by vinyl triethoxysilane (VTES), vinyl trimethoxysilane (VTMS) and γ-methacryloylpropyl trimethoxysilane (MPS). The treated glass fibers were analyzed by fourier transform infrared spectroscopy (FTIR). Dynamic mechanical thermal analysis (DMTA) and thermo-gravimetric analysis (TGA) were employed to investigate the effect of glass fibers surface modification on viscoelastic behavior and thermal properties. The morphology of fracture surfaces of various composites was observed by scanning electron microscopy (SEM). The results revealed that these coupling agents were connected to the surfaces of the fibers by chemical bonding. Dynamic mechanical properties as well as thermal stability of the composites were improved considerablely, but to varying degrees depending on the fiber modification. The diversities of improvement of properties were attributed to the different interfacial adhesion between CLPS matrix and the glass fibers.

The atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) employing ethyl 2-bromoisobutyrate (EBiB)/CuBr as the initiating system was analyzed at 30, 40, 50 and 60 °C in N-methylimidazolium formate ([Hmim][HCOO])/THF mixtures. The polymerization was performed in a well-controlled manner as evidenced by kinetic study and the chain extension result. The apparent activation energy and the enthalpy of equilibrium for the preequilibrium were also investigated. Results show that E _a(app)=47.86 kJ/mol, ΔH ⁰ _eq = 25.67 kJ/mol.

Six groups of segmented polyurethanes with amorphous soft segment domains based on mixed hydrophobic polyester and hydrophilic polyether soft monomers were prepared from 4, 4′-diphenylmethane diisocyanate (MDI), polybutylene adipate glycol 2000 (PBA2000), polytetramethylene glycol 1000 (PTMG1000) and polyethylene glycol 1000 (PEG1000) with 1,4-butanediol (BDO) as the chain extender. Furthermore, the representative properties of the hydrophilic polyurethanes, moisture permeability and water resistance, were investigated. The results show that the chemical structure, molecular weight and concentration of soft monomers have remarkable effects on the main application properties of hydrophilic polyurethane. The important factors in diffusion are the content of hydrophilic ether bond and the mobility of hydrophilic chain in the soft phase, which is represented with a good approximation by the average mean molecular weight of soft segment. On the contrary, the functional properties of the hydrophilic polyurethane are almost not affected by its hard segment.

Bacterial infection plays an important role in the initiation of biliary sludge formation. Bacterial adherence and biofilm formation on the surface of a material have been considered as one of the main factors of stent re-occlusion in clinic. This work reported preventing bacterial adherence and bacterial biofilm formation on the surface of biliary stent material using chitosan film. The chitosan film was deposited on 316 L stainless steel (SS) plate by electrophoresis method and was characterized by X-ray diffraction (XRD), Fourier Transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM). The ability of inhibiting bacterial adherence was investigated by incubating in human fresh bile adding E. coli and Enterobacter at 37±1 °C. Scanning electron microscopy (SEM) and fluorescence staining were used for observing bacterial colonization and biofilm formation. The results show that chitosan film was uniformly deposited on material surface, and the composition of the film did not change through cross-linking, but the crystallinity of chitosan film become well. Comparing to un-modified sample, the E. coli and Enterococcus adhesion amount and colonization on the surface of modified sample were significantly decreased by fluorescence staining and SEM. It is suggested that chitosan could be applied to biliary stent in clinical because of its antimicrobial activities.

The effects of various factors on the synthesis process and the performances of product, including batch feeding way and the dosage of the radical initiator, the system concentration, the reaction temperature and the reaction time were discussed. A kind of polycarboxylate superplasticizer with allyl alcohol polyethylene glycol, maleic anhydride and methacrylic acid sulfonic sodium as main raw materials has been synthesized. Their relative effectiveness as dispersants was evaluated in cement paste by measuring paste fluidity. The optimum parameters of technology and the appropriate proportion of raw materials were obtained. As a result, the new high performance superplasticizer suitable for high-performance concrete has been synthesized. The structure of copolymer was characterized and analyzed by FT-IR spectra. Results indicated that product copolymer structure was consistent with the ideal molecular structure designed.

An IKVAV (Isoleucine-Lysine-Valine-Alanine-Valine)-containing peptide amphiphile molecule (IKVAV-PA) was implanted subcutaneouly into rat backbone in the middle. Angiogenesis induced by IKVAV-PA was evaluated in vivo. 200 μL of 10, 2, 1 and 0.5 wt% IKVAV-PA solution were added into DMEM/F₁₂ and self-assembled into nanofiber hydrogel. 1 mL of 1% IKVAV-PA (Experimental Group, EG) and 1 mL of 16.67% gelatin (Control Group, CG) were injected subcutaneously into rat backbone. The specimens were harvested two weeks after injection and examined immunohistochemically for VEGF(Vascular Endothelial Growth Factor). TEM observations of hydrogels revealed a network of nanofibers, and there was a significant positive correlation between IKVAV-PA concentration and nanofiber alignment. Light microscopy observation showed capillary vessel with complete walls formed in hydrogel, with erythrocytes noted inside the vessels in EG; capillary vessels or erythrocytes were not found within gelatin in CG. Immunohistochemical analysis revealed that there were VEGF-positive cells within hydrogel, which were not found in CG. Self-assembled hydrogel from IKVAV-PA was able to induce the angiogenesis in vivo.

Aiming at the treatment of difficult-to-handle oily wastewater, the ceramics filter mediums made from the iron and steel plant sludge were adopted to surface lipophilic modification so as to remove oil efficiently. The hydrolysis technique by FTIR and conductivity test indicated that under acid conditions hydrogen silicon oil did not hydrolyze but release hydrogen by chemical reaction under alkaline conditions. The results of the experiments including contact angle measurement, FTIR analysis, and SEM analysis illustrate that a layer of lipophile coating indeed exists evenly on the surface of filter mediums after modification. Furthermore, the hydrogen-containing silicone oil was combined through dehydration of Si-H bond with the -OH on the surface of ceramic filter medium.

The effect of cooling rate on the microstructure of ZA48 alloy was investigated. The alloy was prepared using a relatively simple technique, i e, rapid cooling of the melt in a steel wedge mould. The dependence of microstructure on the cooling rate (about 40 to 10³ K/s) was determined by the secondary dendrite arm space size measurement, optical microscopy(OM), and transmission electron microscopy (TEM). It is found that the matrix structure over a large cooling rate is composed of α-Al dendrite and eutectoid (α+η), the size of α-Al dendrite decreases with increasing cooling rate. The relationship between the cooling rate and the secondary dendrite arm space size has been established. TEM shows that a large number of small and dispersed precipitations can be seen in the primary α phase of tip region. Electron diffraction pattern shows that the precipitate phase is Zn₃Mg₂ phase.

Based on the microscopic phase-field model, the structure and migration characteristic of ordered domain interfaces formed between DO₂₂ and L1₂ phase are investigated, and the atomistic mechanism of phase transformation from L1₂ (Ni₃Al) to DO₂₂ (Ni₃V) in Ni₇₅Al _xV_25−x alloys are explored, using the simulated microstructure evolution pictures and the occupation probability evolution of alloy elements at the interface. The results show that five kinds of heterointerfaces are formed between DO₂₂ and L1₂ phase and four of them can migrate during the phase transformation from L1₂ to DO₂₂ except the interface (002)_D//(001)_L. The structure of interface (100)_D//(200)_L and interface (100)_D//(200)_L·1/2[001] remain the same before and after migration, while the interface (002)_D//(002)_L is formed after the migration of interface (002)_D//(002)_L·1/2[100] and vice versa. These two kinds of interface appear alternatively. The jump and substitute of atoms selects the optimization way to induce the migration of interface during the phase transformation, and the number of atoms needing to jump during the migration is the least among all of the possible atom jump modes.

The effects of ultrasonic vibration on the grain size and morphology of Mg₂Si in Mg-4 wt% Al-1 wt%Si(AS41) alloys designed were evaluated. The results show that the major constituents of the alloy include β-Mg₁₇Al₁₂ and Mg₂Si phase, and no difference in the type of constituents between without ultrasonic vibration and with ultrasonic vibration. Without any ultrasonic vibration, the grain size and Mg₂Si phase in AS41 alloy are coare structure. However, the microstructure with fine uniform grains and Mg₂Si particles are achieved with ultrasonic vibration. The crystal grains and Mg₂Si particles refine with increase in the ultrasonic vibration intensity. When the ultrasonic vibration intensity was too low or too high, coarse structures could be obtained. The analysis of refinement mechanism indicates that the acoustic cavitation and flows induced by ultrasonic vibration lead to the fine uniform microstructure.

Particle tracking method is given to analyze the equal channel angular extrusion (ECAE) process of NiTi alloy in non-isothermal condition. The distribution of effective strain, effective stress, the temperature, and strain rate of selected particle tracking points is analyzed respectively. The influence of friction factor is also discussed. The experimental results show that under non-isothermal condition, distribution of strain, stress, strain rate and temperature are inconsistent on relative plane. Final result indicates that distribution of effective strain on xz plane is obviously different from those of isothermal condition; load predication reveals friction factor in this mechanism made little influence on the gross of load.

According to nanoscratch results for the TiN film, an evaluation method for interfacial fracture toughness of thin hard films is presented with fuzzy concepts, which can account for such influential factors in scratch test as surface roughness and material imperfection. Based on configuration changes in scratching curves, the parameters R _V and R _F are defined as the relative ratios of tip vertical displacement and of friction coefficinet. Fuzzy features of the scratching curves are analyzed carefully. The critical load is deduced from fuzzy logic operations and used to calculate the value of interfacial fracture toughness. With this method, the interfacial fracture toughness of TiN/HSS is evaluated approximately as 4.18 MPam^1/2. Results show that the method is valid and can benefit the interfacial adhesion property investigation for thin hard films.

In order to investigate the effects of powder materials and processing parameters on thermal and stress field during laser powder deposition (LPD), a finite element model was developed with the help of ANSYS software. The finite element model was verified by the comparison between the experimental results and computed results. Then LPD processes with different powder materials and processing parameters were simulated by using the FE model. The results show that less difference of thermal conductivity and thermal expansion coefficient between powder material and substrate material produces lower residual stress; higher laser power, laser scanning speed and smaller laser beam diameter can lead higher peak temperature and higher residual stress. The research opens up a way to rational selection of the powder materials and processing parameters for ensured quality.

The effect of CuO on the clinkering process and mineral structure, components and morphology of high C₃S cement clinker was studied. One reference mixture was prepared according to the potential mineral phase components C₃S=75%, C₃A=7%, C₄AF=18% and then was mixed, respectively, with 0.5%, 1%, 1.5%, 2%, 2.5% and 4% CuO. All samples were heated at a rate of 10°C/min to the design temperatures and then maintained for 40 min. Analyses by the glycerol-ethanol method, XRD and SEM-EDS show that the minimum of free lime (f-CaO) content was related to temperature and CuO amount. The higher the temperature, the lower the amount of CuO corresponding to the f-CaO minimum content. CuO promotes the formation and growth of C₃S and C₄AF and a new compound is found. In addition, these phenomena are discussed theoretically. In conclusion, CuO alters the burnability and the formation and structure of C₃S in a high C₃S cement system.

Eight interfacial modifiers were used to improve the interfacial bonding strength between the crumb rubber and matrix of Crumb Rubber Mortar (CRM), and the physical and mechanical properties and microstructure of CRM were also studied. The results show that, the interfacial modifiers obviously improve the interface bonding strength between the crumb rubber and matrix and the whole strength of CRM, and silicone modified styrene-acryl ate-emulsion has the best effect. The rubber-cement matrix interface was proved by SEM that the interfacial modifiers treated rubber showed good adhesion to the matrix.

The dominant factors during early hydration process of cement paste containing 10% metakaolin replacement (MK10) and 10% kaolin replacement (K10) are investigated in comparison to neat cement paste (NCP), and X-ray Diffraction (XRD) analysis is employed to identify the crystalline phases of all specimens. Thermogravimetric (TG) and Differential Scanning Calorimetry (DSC) are used to identify the phase constituents. The amount of acid-insoluble residue (AIR) of all specimens is used to evaluate the unreacted materials. The results indicate that, after the first day, MK act as nuclei for the formation of C-S-H during hydration of C₃S and C₂S, densifying the microstructure of cement paste. Its contribution is mainly due to the fine nature of the MK. From 3 days to 7 days, more and more MK reacts with CH to form C-S-H, making the microstructure denser. The strength contribution is mainly due to the chemical activity of MK.

Through scanning electron microscope (SEM), spectral analysis, and component analysis tests, the interaction theory between asphalt and rubber was discussed. It is concluded that rubber powder become soft and bond together with each other after being mixed with asphalt. The asphalt changes from a smooth homogeneous matter to a continuous mixing system which is composed of rubber powder and asphalt. The interaction is mainly physical diffusion, but there are some chemical reactions in the process, especially at long reaction time.

Corrosion inhibitor is one of the most important technologies to enhance the durability of steel reinforced concrete. A kind of time-saving method was developed to assess the inhibitor efficiency by using a 16 voltage electric field to accelerate the chloride ion diffusion in concrete and inducing corrosion. Both macrocell and microcell current measurements were used to confirm the corrosion initiation status of steel. The comprehensive efficiency of inhibitor shall be assessed in three aspects. The results clearly show the efficiency of different inhibitors, which indicate the reliability of this time-saving method.

The mechanical performance of recycled aggregate concrete (RAC) is investigated. An experiment on the complete stress-strain curve under uniaxial compression loading of RAC is carried out. The experimental results indicate that the peak stress, peak strain, secant modulus of the peak point and original point increase with the strength grade of RAC enhanced. On the contrary, the residual stress of RAC decreases with the strength grade enhancing, and the failure of RAC is often broken at the interface between the recycled aggregate and the mortar matrix. Finally, the constitutive model of stress-strain model of RAC has been constituted, and the results from the constitutive model of stress-strain meet the experiment results very well.

The low-temperature rheological properties of binders in the recycled asphalt pavement (RAP) material without the damaging effects of solvent extractions were analyzed. The developed procedure is based on testing of bitumen-RAP mortars produced by mixing the fresh (virgin) binder with RAP material smaller than # 8 sieve. Different mortars were prepared, containing RAP material passing the #8 sieve and 15% by weight of fresh binder. Low temperature properties of these mortars were investigated by using the bending beam rheometer (BBR) test procedure that is specially modified for testing of the RAP mortars. The modification involved the development of a new kind of mold and different testing parameters. The RAP material used in the experimental study were both extracted from real reclaimed pavement and prepared in the laboratory, by aging binder through repeated PAV cycles. The results indicate the new procedure can capture the effect of aged properties of bitumen in the RAP and can be used to estimate the PG low temperature grade of the blended binder. Although data is limited in size, the modification of the BBR appears to be simple and provide repeatable data.

Design method for large stone porous asphalt mixtures (LSPM) was analyzed to avoid the early distresses of semi-rigid asphalt pavements. Based on stone-to-stone skeleton structure concept, processes of LSPM gradation design was given. The gradation composite design for LSPM shows that the LSPM nominal maximum size (NMS) should be larger than 26.5 mm, and the NMS sieve passing percentage should be greater than 50%. Through experiments and calculations on the volume properties of the aggregate, the range of aggregate gradation curve of LSPM was given. In terms of asphalt binder’s normalized test results, MAC-70 and SBS modified asphalt were selected as the asphalt binders. The applicability of large scale Marshall Method and gyratory compaction method to shape specimens was investigated. Based on the asphalt mixture performance evaluation, the optimum asphalt content range (3.1%–3.6%), the bitumen film’s thickness range (13–16 μm) and the air void range (135–18%) were recommended. Finally, LSPM was tested by the laboratory performance tests including rutting resistance test, fatigue test and water stability test. The theoretic and practical analysis shows that LSPM has a good performance on water permeability, rutting resistance and reflection crack resistance.

Exposure to environmental conditions can significantly influence the mechanical behavior of concrete structures in civil engineering. In this study, the effect of environmental factors, such as moisture and temperature, on the strain-rate sensitivity of concrete mixtures was systematically investigated. The strain rate varied from 10⁻⁵s⁻¹ to 10⁻²s⁻¹. From the investigation it was concluded that moisture content had a significant influence on the strain-rate sensitivity of concrete. With regard to concrete with low moisture content, temperature had little influence on the rate-dependent behavior; while for fully saturated specimens, a significant influence was observed. These phenomena were attributed to the meso-scale bonding properties of the concrete matrix. Equations were derived to characterize the ultimate strength increment of concrete with strain rate under different environmental conditions. An explanation to the dynamic failure mechanisms of concrete based on the experimental findings was proposed.

The behavior of a new type of secondary anode material made of carbon fiber reinforced cement used for cathodic protection of steel in concrete was studied. The mechanical, electrical and electrochemical properties of this conductive mortar were investigated. Results indicate that the addition of carbon fiber enhances the strength and ductility of the mortar, as well as the electrical property. The anodic polarization behavior was tested on specimens immersed in aqueous solutions of saturated Ca(OH)₂ in the presence or absence of 3% NaCl. Based on impedance measurements the electrochemical parameters of conductive mortar were calculated. It is shown that the investigated conductive mortar can be used in cathodic protection of reinforced concrete. The study also shows that the optimum fiber content in mortar should be in the range from 0.5 vol% to 0.7 vol%.

The single influence of capillary porosity and coupling effects of absolute basicity and capillary porosity on concrete carbonation were investigated. The experimental results showed that carbonation rate of concrete at a given absolute basicity (AB) increased moderately with the increase of the porosity ranging from 6.2% to 9.25%, and increased rapidly with porosity from 9.25% to 12.8%.The coupling effect mainly embodied in disappeared mutation point of capillary porosity, and the distributing regions of carbonation depth were clearly partitioned in the coupling influence of absolute basicity and capillary porosity. A design method on carbonation related durability of concrete based on the coupling effects was proposed.

The leaching behavior of three types of mortars was investigated using a self-design device which could simulate the field conditions of pipe lining. The results by ICP and ESEM measurement show that the developed slag cement mortar is suitable for the lining of cast iron pipe that is used for delivering drinking water.