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It is required to develop new paving materials for pavements, such as footpaths, car parks, etc., in parks, having good landscape. Such paving materials have been already developed, but these do not have sufficient strength, abrasion resistance and frost resistance.

In this study, a new paving was examined material using cement, sand and granite soil. The mix proportion of this material tested was 2:4:4 of cement, sand and granite soil by mass. The maximum flexural and compressive strength were both obtained at a water content of 14% of the total mass, and the strength were several times larger than that of paving material on the market consisting of 10% of cement and 90% granite soil. The abrasion resistance was tested according to ASTM C 779, and this resistance was about four times greater than that of the paving material on the market.

The frost resistance was obtained high value compared with the concrete of 72% in water cement ratio by a new simple resisting test method for freezing and thawing using liquid nitrogen and warm water. It is considered that this new paving material is applicable to pavement for footpath, car park, etc.

Strength degradations in silicon nitride ceramics subject to damage from contact with hard spheres are investigated. Strengths against indentation load, number of cycles in contact, or stress-rate parameter are reported and compared with theoretical models. Silicon nitride ceramics are prepared by nitride pressureless sintering (NPS) process, which process is the continuous process of nitridation reaction of Si metal combined with subsequent pressureless sintering. Microstructure characterizations reveal silicon nitride fabricated by NPS process exhibits a quasi-plastic mode, with continuous strength loss beyond a load above the onset of yield, and falloff at high number of cycles, > 10⁵ at contact load, P = 950 N, using WC sphere r = 1.98mm. The strength degradation is substantially faster by dynamic fatigue. Failures originated from contact damages, quasi-plastic microcrack zones, with developing radial cracks during strength test. The implication is that quasi-plastic damage of NPS silicon nitride itself can preserve benefits from the inherent higher damage tolerance at lower number of cycles of contacts, but fatigue susceptibility at multicycle contacts and lower stressing rate.

The effects of vacancies on the strength and elastic constants of silicon, such as Young's modulus and Poisson's ratio are investigated using the molecular dynamics simulations with the Stillinger–Weber potential. The defected crystalline cells contain randomly generated defect distributions in the simulation models. The ideal strength is found to be 33.6 GPa at the strain 0.26. The Young's modulus and Poisson's ratio is 148 GPa and 0.252, respectively. It is found that the strength decreases as the point defect fraction increases, and the variation of the strength versus the point defect fraction coincides with a decaying exponential function. In addition, vacancies are shown to reduce the elastic constants. In general, the elastic constants of silicon vary linearly versus the defect fraction.

Shikoku Electric Power Co., Inc. has developed the technology to manufacture a brand name "Finash" about 12 years ago, by sorting and classifying coal ash generated in coal fired power plants. "Finash" is highly functional fly ash (HFA) is produced by removing irregular coarse particles. It is important for the production of HFA to minimize the variation in quality of coal ash with sophisticated classification technique and extracting good-quality spherical fine particles. It is now widely utilized as concrete admixture for general civil engineering structures and buildings in Japan. When highly functional fly ash (HFA) is used as shotcrete admixture to substitute for fine aggregate of 100kg/m³, the shotcrete has the advantages of decreasing the amount of dust and rebound during spraying operation, improving the hardened properties of concrete, etc. Therefore, it has been applied in many tunnel construction projects. This paper discusses about the various characteristics such as construction placement, strength, neutralization and dry shrinkage of shotcrete using highly functional fly ash (HFA), using the results that is obtained from spray test in an actual road tunnel.

The high-pressure strength of molybdenum (Mo) to 92 GPa has been studied by radial X-ray diffraction (RXRD) technique. The ratio of t/G is found to decrease above $\sim$24 GPa, showing the yield of Mo which is caused by plastic deformation at this pressure. Combined with high-pressure shear modulus, it was found that the differential stress corresponding to the yield of Mo at 24 GPa due to plastic deformation is 1.73 GPa. The second increase of t values occurs after $\sim$66 GPa, suggesting the strength of Mo with a differential stress of $\sim$1.93 GPa. In addition, the maximum difference stress of molybdenum at 87 GPa is 3.01 GPa.

The production of long cellulose macrofibers starting from nanofibers is still complex and expensive. This study proposes a method of manufacturing long macrofibers from plant fiber bundles by chemically extracting non-cellulosic substances but preserving the original shape of the fibers. Once the cellulosic fiber bundles are dried, the original cellulose nanofibers are bridged to neighboring nanofibers by the formation of hydrogen bonds, giving shape stability and enhanced mechanical properties. By the process, the tensile strength was increased by about 50% and the modulus doubled from the original plant fiber bundles.

When wood materials are used for a mechanical structure, the fatigue strength should be estimated due to repeated loads they receive. This paper reveals that the methods to calculate allowable stresses along with American Society for Testing and Materials (ASTM) and Architectural Institute of Japan (AIJ) can take the strength reduction due to fatigue into account because the ASTM/AIJ allowable stresses against the static strength closely resemble the fatigue limit against the wood static strength.

We introduce a new quantity, relevance-strength which describes the relevance of a node to the others in a scale-free network. We define a weight between two nodes i and j based on the shortest path length between them and the relevance-strength of a node is defined as the sum of the weights between it and others. For the Barabási and Albert model which is a well-known scale-free network model, we measure the relevance-strength of each node and study the correlations with other quantities, such as the degree, the mean degree of neighbors of a node, and the mean relevance-strength of neighbors. We find that the relevance-strength shows power law behaviors and the crossover behaviors for the degree and the mean relevance-strength of neighbors. Also, we study the scaling behaviors of the relevance-strength for various average relevance-strength for all nodes.

Municipal solid waste has increased with the development of urbanization which sets a high request to the stability of landfill. The strength of anti-seepage slurry plays a crucial role in the stabilization of landfill. The ratio of each component was changed to test the slurry strength of different ages. Results show that the slurry strength increased with the raise of cement paste because the strength was mainly determined by the skeleton structure. In contrast, the excessive bentonite reduced the strength of slurry, for the excessive bentonite may package the skeleton structure of cement-fly ash instead of filling in. The dosage of Na₂CO₃ and PVA increasing to 3.0 g also reduced the strength of the slurry, because the water absorbability and expansibility of bentonite were inhibited and the effect of reinforcement on cement-fly ash structure was weaken.

The effect of rolling parameters on microstructure and tensile properties of nanocrystalline/microcrystalline 304 stainless steel (SS) casted by the aluminothermic reaction was investigated in this work. It was found that majority of the nanocrystalline austenite of the 304 SS rolled at 700${}^{\circ }$C and 900${}^{\circ }$C grew up and transformed to sub-microcrystalline. While the nanocrystalline/microcrystalline structure still retained rolled at 900${}^{\circ }$C with 40% deformation followed 600${}^{\circ }$C with 70% thickness reduction, and microcrystalline austenite grains distributed evenly. The strength and ductility of the various rolled 304 SS were improved compared with the as-casted 304 SS steel. The steel rolled at 900${}^{\circ }$C with 80% deformation exhibited a uniform elongation as large as 31.3%, which is almost the same ductility level of counterpart coarse-grained steel. The rolled steel at 700${}^{\circ }$C with 80% deformation achieved the maximum tensile strength but the smallest elongation. The sample, two-step rolled at 900${}^{\circ }$C with 40% thickness reduction and then 600${}^{\circ }$C with 70% thickness reduction, yielded the satisfactory combination of strength and ductility. The yield strength and elongation were appropriate 767 MPa and 22.8%, respectively, which resulted from the optimized nanocrystalline/microcrystalline structure and distribution.

Until recently, limited evidence existed to support the efficacy of exercise programs for patients scheduled for total hip arthroplasty (THA), and no evidence-based guidelines were available regarding the length or intensity of exercise programs and their effect on patient recovery. The purpose of this randomized controlled trial was to determine the impact of an eight-week pre-surgery and 20 week post-surgery customized exercise program on the strength and function of subjects scheduled for THA. A series of physical tests and quality of life questionnaires were completed by patients (n = 57) pre-surgery and on three occasions post-surgery. In the week prior to surgery, the exercise group exhibited significant improvements (p < 0.05) in composite hip strength score and WOMAC total score in comparison to control subjects. By week 24, post-surgery scores for WOMAC total score, Harris Hip score, composite strength score, hip flexion range of motion of the operated hip and the distance walked in 6 minutes were significantly (p < 0.05) better in exercise group patients. A detailed description of the exercise intervention is presented in this paper.

The purpose of this study was to investigate the strengths of four intrinsic muscles of the hand of college baseball players. The strengths of four intrinsic muscle groups were measured by the Rotterdam Intrinsic Hand Myometer (RIHM) which has been developed to assess the abduction of the little finger and index finger, and palmar abduction and opposition of the thumb. The strengths of these four intrinsic muscle groups were compared between baseball players and inexperienced sports players.

The abduction of the little finger and index finger, and the opposition of the thumb in both the dominant and nondominant hands of the baseball players were notably stronger than those of the inexperienced sports players. There was no statistical difference in the strength of the palmar abduction of the thumb between the two groups. The results suggest that the specific intrinsic muscles in both the dominant and nondominant hands might be strengthened by repeated baseball practices, such as a batting performance, which requires strain in both the dominant and nondominant hands repeatedly.

The aim of the current study was to explore the effects of compound (CPD) versus complex training (COX), resistance and plyometric training alone on vertical jump (VJ) height, 20-m sprint time, agility T-test, muscular strength, and endurance in women. A total of 29 healthy women volunteered to participate in this study and were randomly divided into four training groups: plyometric training alone (PT, n = 8), resistance training (RT) alone (RT, n = 7), CPD training (one day PT and another day RT, n = 7), and COX (PT and RT in a session, n = 7). All participants performed their training program twice a week for six weeks and were tested in VJ, sprint (20-m), agility T-test, one repetition maximum leg press (1RM_LP), and muscular endurance (60% of 1RM_LP) pre- and post-six weeks training period. Statistically, significant improvements were observed in all groups in VJ, 1RM_LP, and muscular endurance: PT (19% [ES = 1.59], 45% [ES = 2.95], and 51% [ES = 1.86]), RT (20% [ES = 1.02], 48% [ES = 3.82], and 68% [ES = 2.24]), CPD (27% [ES = 1.79], 40% [ES = 4.23], and 34% [ES = 0.72]), and COX (17.5% [ES = 1], 37% [ES = 1.63], and 65% [ES = 2.25]), respectively. Also, significant decrease was observed in all groups in 20-m sprint time and T-test: PT (15% [ES = 1.01], and 7.6% [ES = 1.1]), RT (7% [ES = 0.89], and 6% [ES = 0.97]), CPD (15% [ES = 1.75], and 8% [ES = 1.1]), and COX (9% [ES = 0.72], and 3% [ES = 0.46), respectively. We found that PT, RT, and combined PT and RT induced positive effects on performance of the women. Also, the CPD group exhibited greater increase in agility performance in comparison to PT. With regard to ES, the CPD group showed greater increase in muscular performance in comparison to other groups.

Background: Patellar taping has long been reported to be effective in relieving pain in patients with patello-femoral pain syndrome (PFPS). Yet, there is lack of knowledge that supports its use in knee osteoarthritis (OA) management. Purpose: This study examined the effect of therapeutic patellar taping on concentric and eccentric quadriceps muscle peak torques, VAS pain scores, 6-minute walking distance and stair climbing time in patients with knee OA. Methods: A total of 30 female patients with symptomatic knee OA with mean age 51.8 ± 6.3 years and BMI 32.56 ± 3.26 m²/kg participated in the study. They were tested under three taping conditions that were tested randomly; therapeutic, placebo and no-tape. Results: Repeated measure MANOVA revealed that the quadriceps muscle peak torques and 6-minute walking distance increased significantly (p < 0.05) and the VAS scores and stair climbing time decreased significantly with therapeutic tape use compared with the other two tapes. Moreover, the quadriceps muscle peak torques increased significantly and the VAS scores decreased significantly with placebo tape use compared with no-tape use, with no significant difference (p > 0.05) in between for the 6-minute walking distance and stair climbing time. Conclusion: The findings indicate that therapeutic patellar taping is effective in improving quadriceps strength and functional performance and reducing pain in patients with knee OA.

Background: Knee traumata are associated with arthrogenic muscle inhibition (AMI). We aimed to identify impact factors on AMI. Methods: A total of 37 patients with meniscus injuries were interviewed and examined for maximum isometric knee extensor force preoperatively. We analyzed AMI as relative maximum isometric force between healthy and injured legs. Regression analyses were computed to evaluate associations between an AMI with muscle-strength reduction $>25$% and several parameters and between cartilage damage$>$stadium 3 and several parameters. ROC curves were calculated to investigate effectiveness of age and pain at rest for prediction of cartilage lesions $>$stadium 3. Results: Meniscus injuries lead to distinct AMI with reduced strength of 26.6% in mean. In multi-variate logistic regressions, an AMI with muscle weakness $>25$% was associated with higher severity of cartilage lesions (OR3.267, 95% CI 1.059–10.078, $p=0.0394$). In uni-variate regression analyses, pain at rest (OR1.398, 95%CI 1.071–1.824, $p=0.0137$) and patients’ age (per year) (OR1.145, 95%CI 1.042–1.257, $p=0.00488$) were associated with cartilage damage$>$stadium 3. Optimal cut-off values for patients’ age and pain at rest to predict cartilage damage stadium$>3$ were 44.5 years and VAS-scale-value 4.5 with good effectiveness (AUC 0.855 and 0.732), respectively. Conclusions: Meniscus injuries lead to distinct AMI with 26.6% reduction in muscle strength. Concomitant cartilage damage is an important cofactor for development of distinct AMI. Moderate to severe pain at rest and age $>44.5$ years were indicators for concomitant higher cartilage damage in patients with meniscal lesions.

Notions of rank abound in the literature on tensor decomposition. We prove that strength, recently introduced for homogeneous polynomials by Ananyan–Hochster in their proof of Stillman’s conjecture and generalized here to other tensors, is universal among these ranks in the following sense: any non-trivial Zariski-closed condition on tensors that is functorial in the underlying vector space implies bounded strength. This generalizes a theorem by Derksen–Eggermont–Snowden on cubic polynomials, as well as a theorem by Kazhdan–Ziegler which says that a polynomial all of whose directional derivatives have bounded strength must itself have bounded strength.

In this paper, the biomechanical effectiveness of prophylactic augmentation in preventing fracture was investigated. In vitro biomechanical tests were performed to assess which factors make prophylactic augmentation effective/ineffective in reducing fracture risk. Nondestructive and destructive in vitro tests were performed on isolated osteoporotic vertebrae. Five sets of three-adjacent-vertebrae were tested. The central vertebra of each triplet was tested in the natural condition (control) non-destructively (axial-compression, torsion) and destructively (axial-compression). The two adjacent vertebrae were first tested nondestructively (axial-compression, torsion) pre-augmentation; prophylactic augmentation (uni- or bi-pedicular access) was then performed delivering 5.04mL to 8.44mL of acrylic cement by means of a customized device; quality of augmentation was CT-assessed; the augmented vertebrae were re-tested nondestructively (axial-compression, torsion), and eventually loaded to failure (axial-compression). Vertebral stiffness was correlated with the first-failure, but not with ultimate failure. The force and work to ultimate failure in prophylactic-augmented vertebrae was consistently larger than in the controls. However, in some cases the first-failure force and work in the augmented vertebrae were lower than for the controls. To investigate the reasons for such unpredictable results, the correlation with augmentation quality was analyzed. Some augmentation parameters seemed more correlated with mechanical outcome (statistically not-significant due to the limited sample size): uni-pedicular access resulted in a single cement mass, which tended to increase the force and work to first- and ultimate failure. The specimens with the highest strength and toughness also had: at least 25% cement filling, cement mass shifted anteriorly, and cement-endplate contact. These findings seem to confirm that prophylactic augmentation may aid reducing the risk of fracture. However, inadequate augmentation may have detrimental consequences. This study suggests that, to improve the strength of the augmented vertebrae, more attention should be dedicated to the quality of augmentation in terms of amount and position of the injected cement.

A seismic design procedure for partially concrete-filled box-shaped steel columns is presented in this paper. To determine the ultimate state of such columns, concrete and steel segments are modelled using beam-column elements and a pushover analysis procedure is adopted. This is done by means of a new failure criterion based on the average strain of concrete and steel at critical regions. The proposed procedure is applicable to columns having thin- and thick-walled sections, which are longitudinally stiffened or not. An uniaxial constitutive relation recently developed is employed for concrete filled in the thick-walled unstiffened section columns. Modifications are introduced to this model for other types of columns. Subsequently, the strength and ductility predictions obtained using the present and previous procedures are compared with the corresponding experimental results. Comparisons show that the present procedure yields better predictions. It is revealed that the inclusion of the confinement effects and softening behaviour of concrete is important in the present kind of prediction procedures. Furthermore, an extensive parametric study is carried out to examine the effects of procedures and geometrical and material properties on capacity predictions.

This paper describes the concentric compression test results of carbon fibre reinforced polymer (CFRP) composite sheet jacketed concrete specimens with circular, square and rectangular cross-sections. In the experimental program, pre-damaged specimens and repeated compressive loads were considered as well as undamaged specimens and monotonic compressive loads. The contribution of CFRP composite jackets to the compressive behaviour of the specimens is evaluated quantitatively, in terms of strength, longitudinal and lateral deformability and energy dissipation. Simple analytical expressions are proposed for compressive strength and ultimate axial strain that are valid for CFRP composite jacketed concrete with circular, square and rectangular cross-sections. The analytical results obtained by the proposed expressions are in good agreement with the experimental data obtained in this study, as well as the experimental data available in literature.

A summary of dynamic measurements are presented that illustrate relations between linear seismic demand and true nonlinear response of unreinforced masonry buildings with flexible diaphragms and rocking piers subjected to a series of simulated earthquake motions.