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Marine soft clays are prevalent in coastal regions of China, giving rise to engineering challenges such as salt swelling, corrosion, and load bearing in foundations with soft soil. This study is dedicated to enhancing the mechanical properties of fiber-reinforced cement-stabilized soft clay (FCSSC) and revealing its strengthening mechanism. Uniaxial compression tests are performed to explore the impact of fiber length, fiber amount, and curing ages on mechanical behavior. The stabilization mechanisms of cement and glass fibers are explored through damage analyses and microscopy. Based on the experimental results, a damage constitutive model is formulated for FCSSC, and its validity is established by comparing fitting curves with testing curves. The results demonstrate a significant improvement in the mechanical properties of the stabilized soil, attributed to the synergistic effects of the cement and glass fibers. The growth rate of the unconfined compressive strength decreased with increasing curing ages. Notably, the fiber length significantly impacted the strength index, with short-chopped fibers playing a crucial role in strength enhancement. The compressive strength exhibited an initial increase followed by a decrease with rising fiber content, reaching a maximum between 0.3% and 0.4%. The bridging effect of the glass fibers proved effective in inhibiting compression crack expansion and mitigating structural damage of the soil sample. However, excessive fiber content or length led to improved local porosity, resulting in the deterioration of strength and deformation properties. The stress–strain curves fitted using the proposed damage constitutive model accurately reflected the stress–strain relationship and deformation characteristics of the FCSSC. [ABSTRACT FROM AUTHOR]

Wind energy is an important clean energy, according to China's carbon peak and carbon neutral strategy, the policy of replacing small with large wind turbine blades and replacing old with new is imperative. The main material of wind turbine blades is glass fiber reinforced polymer, which has problems of difficult recycling technology and high recycling cost. Nowadays, there is no ideal large-scale recycling method. Therefore, the systematic and high-value utilization of waste wind turbine blades is imminent. In this paper, the material type, recycling methods and their respective characteristics of wind turbine blades are summarized. The recent developments of waste wind turbine blades in cement-based materials and thermoplastic polymer materials are thoroughly discussed. Overall, this paper can provide reference for the subsequent development and research on the recycling waste wind turbine blades. [ABSTRACT FROM AUTHOR]

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The removal of NOx by cobalt ethylenediamine solution has attracted much attention, but its reaction mechanism is still not clear. In this study, the reaction mechanism was analyzed experimentally and through practical engineering experiments for thirteen consecutive days. The results indicate that the removal of NOx by cobalt ethylenediamine solution can be divided into two steps. For industrial applications, the removal of actual flue gas NO by cobalt ethylenediamine absorbent was investigated by a gas‐liquid countercurrent and concurrent system in a glass fiber factory in Neijiang, Sichuan province in China, indicating that the average removal efficiency of NO and NOx reached 80 % and that of SO2 90 %. [ABSTRACT FROM AUTHOR]

As a kind of highly weathered special soil in South China, granite residual soils (GRS) feature high strength and high void ratio in a dry environment, so they tend to disintegrate in water and cause geological disasters including collapse. Therefore, modifying GRS for higher strength has become a hot spot. Glass fiber reinforced soils boast fewer cracks, higher energy absorption, and residual strength. This study aims to analyze the reinforcement effect of glass fibers on GRS with inorganic and organic solutions and its environmental feasibility. The inorganic solution contains silicon ion and sodium ion at the ratio of 1 : 4 (hereinafter referred to as Si : Na = 1 : 4 solutions), and the organic one is a modified polyvinyl alcohol solution (hereinafter referred to as SH solution). The reinforced samples were subjected to plate and impact load tests, SEM, and XRD analysis to investigate their mechanical properties, microcharacteristics, and the components produced. Results indicate that the reinforcement effect of glass fibers on GRS under Si : Na = 1 : 4 solutions was better than that of SH solutions. After being reinforced by Si : Na = 1 : 4 solutions, the samples reached maximum impact resistance. SEM results show that glass fibers bond more soil and form an integral structure; thereby the strength was improved as glass fibers share external impact load. XRD results show that geopolymer and alkali-activated materials and potassium feldspar were formed. Geopolymer and alkali-activated materials are pollution-free, inorganic polymers featuring viscosity and high compressive strength. Potassium feldspar is an aluminosilicate mineral with high strength and stable chemical properties, which can adhere to more granules and form a stronger whole structure with geopolymers playing a role. Therefore, it is feasible to reuse these soils sustainably by reinforcing them with glass fibers and the best Si : Na = 1 : 4 solutions. This study finds a new direction for recycling and reusing construction waste, GRS. [ABSTRACT FROM AUTHOR]

Difficult picking is often found in the harvesting of fresh chestnut, particularly in the low efficiency and high labor cost of manual harvesting, as well as the high risk of high-altitude picking. However, only a few research focused on this field in China. In this study, a beating-type fruit dropping device was proposed for a chestnut harvester, according to the characteristics of chestnut trees and the planting mode of Chinese chestnut. The overall structure and working principle were also introduced into the design of the chestnut harvester. Two situations were included to separate the chestnut fruit from the branch. When the beating strips hit the fruit, the beating force was directly transferred to the fruit. As such, the fruit was separated from the branch, if the beating force was greater than the binding force between the fruit and the branch. When the beating strips hit the branch, an inertia force was transmitted from the branch to the fruit, where the chestnut was separated from the branch to complete the chestnut harvest, if the inertia force was greater than the binding force. A beating mechanism was also designed as a crank-rocker without quick returning, in order to ensure the overall performance of the machine, and the stability of the fruit dropping device in the process of operation. The size of the crank-rocker mechanism was also determined under the optimal conditions. A kinematic model was established for the crank-rocker mechanism, further to obtain the kinematic relationships of angular displacement, angular velocity, and angular acceleration of the rocker. A dynamic simulation was also performed on both sides of the beating device in the crank-rocker mechanism. It was found that the motion of the rocker was symmetrical in terms of the motion curve, where the swing angle of the rocker reached 60° suitable for the stability requirements. Furthermore, the variation of separation force between chestnut fruit and branch was obtained at different tension angles. Specifically, the separation force decreased gradually with the increase of tension angle in the range of 0°-90°, where the maximum separation force was 65.24 N at 0° tension angle. The collision model between the beating strips and the branch was established to determine the main factors affecting the beating force, including the speed of the motor, the length of the beating strips, and the beating angle. A three-factor three-level orthogonal test was conducted, where the materials of beating strips were selected as poly urethane, low-density polyethylene, iron sheet, and glass fiber. The results show that the maximum beating force was only 44.31N for the polyurethane, while the maximum separation force of chestnut fruit and branch was 65.24 N, indicating that the maximum beating force provided by polyurethane was less than that of chestnut fruit and branch, fail to meet the requirements of beating force for fruit picking. The maximum beating forces of iron sheet and glass fiber were 87.46 N and 94.03 N, respectively. Nevertheless, the excessive force was easy to damage chestnut branches. Fortunately, the maximum beating force of low-density polyethylene was 70.71 N, similar to that of chestnut fruit and branch (65.24 N), indicating the best beating material. In this case, the optimal combination was achieved, where the motor speed of 600 r/min, the beating strip length of 350 mm, and the tapping angle of +20°. A field test of the chestnut harvesting machine was carried out to verify each area for harvesting. Several areas were selected on the chestnut tree for the harvest experiment after the positioning structure moved the fruit dropping device. The field test shows that the beating force provided by the fruit dropping device can effectively beat the chestnut fruits within 10s, where the fruit drop rate was 90.1%, while less damage to the chestnut trees. Consequently, the beating-type fruit dropping device can fully meet the harvest requirements of chestnut fruits. The finding can provide a strong reference for further research and development of chestnut harvesting machinery. [ABSTRACT FROM AUTHOR]

Low tunnels are ever increasingly used in vegetable cultivation and seedling production in modern agriculture. The construction area of low tunnels was up to 1.3 million hectares in China. A typical low tunnel is 2 to 3 feet high and covers the width of a growing bed. However, most low tunnels were built manually, indicating high labor intensity with low efficiency. In this study, a novel machine was designed to combine the double-cottage and film covering for vegetable and fruit planting in low tunnels. The machine is mainly composed of automatic shed-pole feeding, double-cottage, and cover film device. As such, the shed poles were automatically inserted, according to the set distance between the shed poles. Specifically, the pole was made of glass fiber reinforced plastic (GFRP), where the length and diameter were 2000 mm and 7.5 mm, respectively. The automatic shed-pole feeding device included a motor, a frame of shed pole, dial wheel, limit ring, and tilt board. The double-cottage device consisted of a hydraulic transmission, arm bending, crank slide, shed-pole cottage, and variable distance adjustment board. The motor of the automatic shed-pole feeding device was used to push the shed poles to the arm bending in the variable distance double-cottage device. The reasonable design of the dial wheel and rod frame was the key issue to ensure the feed of a single rod at a time. The success rate and the time of feeding shed poles were chosen as the indicators to evaluate the performance of the automatic shed-pole feeding device. Theoretical calculation and simulation were conducted, where the main variables were the radius of the dial wheel, the height of the pole groove, and the length of the tilt board. An optimized combination was achieved, where the radius of the dial wheel was 75 mm, the height of the pole groove was 6 mm, and the length of the title plate was 150 mm. Finally, afield test was carried out to verify at an operating speed of 1.2 km/h. Optimal performance of the machine was achieved, where the success rate of shed-pole feeding was 94.1%, while the rate of shed-pole insertion was 98.6%, and the overall success rate of building shed-pole scaffolding was 89.3%, the film coverage rate of low tunnels was 100%, and the breakage rate of film was 1.1%. In insertion, the average width and depth were 1050 mm and 200 mm, respectively, while the average separating distance was 1190 mm, and the average deviation of depth on both sides was 30 mm, and the average thickness of soil covering was 80 mm. Therefore, the double-cottage machine with variable distance was expected to automatically implement the intelligent operation of low tunnel construction. High efficiency and stability were also obtained to reduce manual operation and cost investment. The finding can provide a sound reference for automated smart construction of arched sheds, further promoting the facility of horticulture. [ABSTRACT FROM AUTHOR]

In the asphalt pavement with semi-rigid base, the shrinkage cracks initiating from base course often propagate upward to surface course to develops into reflective cracks. The fiberglass grid, as a woven geotextile, is widely used to retard the occurrence of reflective cracks in China, but the impacts of material composition and knitting methods of it on reflective cracks are still not clear. In this paper, two kinds of models, including a two-scale model of fiber bundle-fiberglass grids layer and a coupled thermo-mechanical model of pavement structure, are established. In the two-scale model, the elastic constants (ECs) of fiber bundle and fiberglass grids layer are calculated under different compositions and knitting methods and then assigned to the coupled thermo-mechanical model to estimate the fatigue lives at initiation phase (FL-IP) and propagation phase (FL-PP) of reflective cracks based on an estimation theory. Moreover, this study designs the laboratory tests to validate this estimation method of fatigue life. Then, based on the predicted fatigue life at different phases of crack progression, the sensitivity analysis is implemented to analyze the impacts of composition and knitting methods on the fatigue life. As a result, the recommendations on design and preparation of fiberglass grid are proposed. The results show that, in material composition, the glass fibers with high elastic modulus and volume fraction and the coating materials with high elastic modulus are beneficial to retarding the initiation and propagation of reflective cracks and in knitting methods, increasing density of fiber bundles parallel to the traffic direction and reducing braided angle also has positive effect. These results can be used to optimizing design and preparation of fiberglass grid to reduce the occurrence of reflective cracks in asphalt pavement. [Display omitted] • Two-scale model of fiberglass grids layer is developed. • A fatigue life estimation method is proposed for the crack initiation and propagation phases. • The material compositions and braid parameters of the fiberglass grid affect crack initiation and propagation. • The study presents recommendations for the design and preparation of fiberglass grid. [ABSTRACT FROM AUTHOR]

• An energy and exergy model for a fiberglass furnace with oxygen-fuel combustion and waste heat recovery was verified. • The energy efficiency of the fiberglass furnace was improved to 74.76%, higher than the data from the present references. • The sources, quantity, reduction potential and cost associated with the CO 2 emissions of fiberglass furnaces were supplemented and updated. • The chemical exergy, exergy loss and irreversibility were determined in process analysis. Energy savings and emission reductions in the building materials industry are key components of China's "dual carbon" goals. A new mathematical model of material, energy, exergy, and carbon flows was established and verified against operational data for an 80600 t/y fiberglass furnace in China. The model enables thermal budget calculation along different paths and analysis of the losses and saving potential of the entire fiberglass melting furnace and its three major subsystems. The results indicated that the selected fiberglass furnace attained a satisfactory performance with a specific energy consumption of 4.63 MJ/kg and an energy efficiency of 74.76%. Oxy-fuel combustion provided a substantial overall fuel reduction relative to air combustion. Moreover, the exergy efficiency and effective exergy efficiency reached 62.85% and 55.23%, respectively. The heat recovery system increased the exergy efficiency by 11.01%. Furthermore, the CO 2 emissions associated with glass production, major contributors, CO 2 reduction potential, and economic impact were obtained. Finally, a sensitivity analysis of the combustion chamber was conducted. This approach could identify the degree of resource and energy utilization and support the implementation of energy and exergy efficiency improvement and CO 2 emission reduction schemes. [ABSTRACT FROM AUTHOR]

• Evaluation of a GFRP sewage pipe that failed after 15 years in an oilfield in China. • The analysis and research are carried out in three depths along the axial and radial directions of the composite pipe. • The microstructure and micromechanical properties of glass fiber reinforced composite pipes after failure were evaluated. • Degradation of amine curing agent and oxidative decomposition of epoxy resin occurred in the outer layer of the pipeline, and the resin content decreased. • The nano-hardness and elastic modulus of the resin deteriorated after the pipeline was aged, and the fiber-resin interface performance decreased significantly. The research was conducted on failed GFRP pipes used in sour oilfield gathering and transportation pipelines, with the matrix material being an epoxy resin of an aromatic amine system that destructively cracked after 15 years of operation. To determine the cause of the failure, the failure area of the GFRP pipe was compared to the undamaged area, and the pipe's micro-morphological structure, chemical composition, and mechanical properties were examined. The results show that there are cavity defects in the GFRP pipe with insufficient air bubbles and resin filling, that the overall resin content of the pipe is low, that the curing degree of the outer layer of the damaged area (DA-OL) is severely insufficient, and that the fiber bonding strength is weak. The degradation of the amine curing agent in the outer layer of the pipeline and the oxidative decomposition of the resin were characterized using Fourier transform infrared spectroscopy and X-ray electron spectroscopy, and an irreversible chemical degradation process occurred, reducing the performance of the fiber–matrix interface. The data from nanoindentation and dynamic thermomechanical characteristics confirmed the obvious reduction of nano-hardness and elastic modulus in the outer layer of GFRP tubes. The failure of the pipeline is caused by the interaction of the above factors. [ABSTRACT FROM AUTHOR]

The Yangtze River Crossing Project, which is part of the Chinese gas pipeline trunk network and aims to transmit the natural gas to the Yangtze River Delta area, sets up a record for the length of Horizontal Directional Drilling(HDD) in the world. The term of pipeline installed is 3300m, and the diameter is 40in. Many technical difficulties have been inevitably encountered in a large diameter hole reaming in fine sand, the calculation of section scour depth which determines the minimum buried depth of the pipe, protection of outside coating and the method of long distance pilot hole drilling, such other challenges. In view of this, it was recommended that two pipelines of 711mm should be installed to replace the existing one of 1016mm in diameter and 1% flooding scour depth obtained by reliable statistical analysis. In period of installation, application glass fiber reinforced epoxy resin as a protective coating, executing the pilot hole by Intersect Method. As a result, this super project is finished successfully on May 21.2013. The experience can be applied to any pipeline engineering the installed by horizontal directional drilling or similar works. [ABSTRACT FROM AUTHOR]

The coal-based energy production in China generates more than 600 million tons of coal fly ash (CFA) each year, which drives us searching for new methods for recycling CFA. In this work, continuous glass fibers with a range of CFA (25–45%) were successfully prepared without showing any sign of fiber crystallization. The measured fiber tensile strength was found to increase with CFA proportionally. The fiber derived from 45% CFA exhibited the best tensile strength (higher than the E glass fiber prepared/tested under the same conditions) and good chemical stability (98% mass retention in the acid corrosion test). Our study shows a feasibility of making continuous CFA derived glass fibers with high iron oxide content and an alternative way for CFA recycling. Its improved strength and good chemical durability can benefit both economy and environmental protection. [ABSTRACT FROM AUTHOR]

This section offers news briefs on the glass industry as of April 2011. The European Union (EU) Glass Container Federation has released figures stating that 11 billion tons of glass bottles and jars were collected for recycling in Europe in 2009. Morgan Thermal Ceramics has launched its new Superwool Plus insulating fibre blanket in Europe in April 2011, while fibre glass manufacturer Owens Corning opened a new production facility in the Yuhang Economic and Development Zone in Hangzhou, China.

Salmonid are farmed far offshore in a submersible cage in China, and air supplementation in the swim bladder is an important issue while the fish are confined in the submersed cage. The objective of this study is to test the effects of different types of air supplementation on the growth, energy budget, and fatty acid composition of the rainbow trout, Oncorhynchus mykiss , confined underwater. The fish were divided into four groups with four replicates (63.84 ± 2.03 g, 13 fish per tank): The control group fish (Ctrl) were cultured in a glass fiber tank with airstone; The mesh group (ME) used a net in a tank to keep the experimental fish from the water surface, and an airstone above the net; The airstone group (AM) added an airstone under the net; And the airdome group (DM) added an airdome under the net. At the end of a 35-day trial, the final mean weight (70.00 ± 1.63 g), percent weight gain (7.09 ± 0.96%) and survival rate (76.92 ± 0.00%) of the fish in ME group were significantly lower than those in Ctrl group (91.54 ± 5.19 g, 43.49 ± 10.35% and 100.00 ± 0.00%, respectively). The final mean weight of AM group was significantly lower than that of Ctrl group, whereas there were no significant differences in other growth indexes between control group, DM and AM group. The proportion of feeding energy allocated to growth in ME group was the lowest, the proportion in AM was significantly higher than ME group and lower than Ctrl group, and there was no significant difference between those in DM and Ctrl groups. The muscle saturated fatty acid level in Ctrl group was significantly lower than those in other groups. In conclusion, the growth of rainbow trout confined underwater for 35 days will slow down due to lower proportion of feeding energy allocated to growth and higher proportion to respiration. The addition of an airdome or airstone can partially compensate for the growth of the fish confined underwater long time. Rainbow trout confined underwater can partially compensate for the loss of buoyancy through increasing the muscle saturated fatty acid content. • Removing surface access for rainbow trout is not feasible, and an air-dome or bubbling partially solved the swim bladder air loss issue from long-term diving. • The empty swim bladder leads to the increase of crude fat content and saturated fatty acid ratio in muscle. • The effects of airdomes, also combined with larger bubble airstone on the growth of salmonid fish need to be studied further. [ABSTRACT FROM AUTHOR]

A soil reinforcement system using the combination of glass-fiber-reinforced polymer (GFRP) pipe and pressure grouting has been developed by a Korean company. The system is being adopted as slope stabilization measures in Hong Kong. Individual GFRP pipes were designed and installed as soil nails with the exception that two-stage pressure grouting was applied instead of gravity grouting. A full-scale field evaluation on constructability and in situ performance of the system was performed in Hong Kong. The performance of the constructed nails was evaluated by pullout tests. The construction procedure, site adaptations of the Korean product made in Hong Kong, field test procedure, and performance of the constructed soil nails are reported in this paper. [ABSTRACT FROM AUTHOR]

Anyone who has visited Jushi Group''s fibreglass plant in the Tongxiang Economic Development Zone, China, cannot fail to be impressed by the sheer size of the operation. And the company is expanding even further. Amanda Jacob visited the company after the China Composites Expo tradeshow this September. [Copyright &y& Elsevier]

• Use modified emergy ecological footprint method to assess sustainability of the wind farm during its whole life cycle. • Uncertainty analysis was conducted to judge the influence on the ecological footprint when UEVs of materials in the input data perturbed. • Provide recommendations concerning management for wind farms. Wind power generation has always been considered as clean energy, according with national ecological civilization construction and responding to climate change. However, from the perspective of resource conservation, wind farms directly or indirectly occupy a large amount of land resources along the entire life cycle. Based on the emergy analysis, this paper estimates the ecological footprint of a wind farm in Dalian, evaluates its sustainability, and analyzes the ecological footprint of the four phases which include wind turbines production and transportation, construction, operation and maintenance, and demolition during the life cycle of the wind farm. It was concluded that the emergy carrying capacity of the wind farm was 3879.57 hm2/a, and the emergy ecological footprint was 5117.59 hm2/a. The wind farm was in an ecological deficit. Among the four phases, the ecological footprint of construction was the largest (60.93%), wind turbines production and transportation phase (33.77%) took the second, followed by operation and maintenance (4.59%) and demolition (0.71%). The main contribution of the materials was steel, followed by concrete, ecological protection investment, fiber glass, land occupation and epoxy resin. Finally, in order to illustrate the way to achieve sustainable development of the wind farm, uncertainty analysis and scenario analysis were carried out. It was found that when 62% of the recycled materials were used for wind turbines production, the wind farm realized ecological balance. Reducing the solar transformity (UEV) of steel and concrete can also decrease the ecological footprint of the wind farm. [ABSTRACT FROM AUTHOR]

This article briefly described the formation, structure design and performance of warp-knitted mesh fabric. Based on the projects the author has undertaken, he explained application of warp-knitted mesh fabric in high-tech textiles. Taking the development of warp-knitted mesh fabric as examples, the author expounded the main points of technology innovation for warp-knitting industry. [ABSTRACT FROM AUTHOR]

This section offers news briefs on the glass industry as of August 2009. A new generation of glass wool (G3) that meets the criteria for sustainable construction was launched by Saint-Gobain Isover in France. One of the topics discussed at a workshop held in Montpellier, France from May 4 to 5 was the production of high quality glasses for research. Paul Wang was named managing director of Owens-Illinois (O-I) in China.

The annual output of the Chinese fibreglass industry reached 950 000 tons in 2005, making China the world''s second largest glass fibre manufacturer. We review the latest statistics from the China Fiberglass Industry Association. [Copyright &y& Elsevier]

The article reports on the plan by Dallas, Texas-based Celanese to open a new polymer emulsions facility in Nanjing, China. The plant, the 10th global polymer emulsions facility operated by Celanese, is expected to produce environmentally friendly latex emulsions for use in the adhesives, nonwovens, glass fiber and low odor architectural coatings markets in Asia. It is part of a larger chemical complex being implemented in China. Celanese also announced its plan to open a new laboratory in Shanghai to support coating, adhesive, nonwovens and glass fiber customers in the region.