Abstract In order to study the load-bearing performance of electrically conductive concrete lightning protection poles, a finite element model poles was established and deformation capacity were analyzed using ABAQUS software. The results show that use prestressed reinforcement can significantly improve bending ultimate pole. Increasing ratio outer diameter load capacity, but increasing wall thickness has limited effect on enhancing poles. This provide theoretical basis for technical application

Abstract With the invention of chirped pulse amplification for lasers in mid-1980s, high power ultrafast entered into world as a disruptive tool, with potential impact on broad range application areas. Since then, have revolutionized laser-matter interaction and unleashed their applications manufacturing processes. unprecedented short duration laser intensity, focused optical energy can be delivered to precisely defined material locations time scale much faster than thermal diffusion...

Anefe cientreliability analysis method fordurability of structural components subjected to external and inertial loads with time-dependent variable amplitudes is presented. This able support reliability crack-initiation crack-propagation lives practical applications, considering uncertainties such as material properties, manufacturing tolerances, initial crack size. Three techniques are employed the probabilistic durability prediction: 1 ) strain-based approach for multiaxial...

In projection stereolithography (SL) processes, the separation of a newly cured layer from constrained surface is historical technical barrier and still greatly limits its printable size, process reliability, print speed. This paper presents an approach to reduce force in SL processes by texturing with radial microgroove patterns. Separation forces conventional smooth textured are both modeled. The analytical model suggests that proper design micropatterns capable reducing greatly....

We report on experimental study chemical etch selectivity of fused silica irradiated by femtosecond laser with either linear or circular polarization in a wide range pulse energies. The relationships between the rates and energies are obtained for different states, which can be divided into three regions. A drop rate high energy region is observed underlying mechanism discussed. advantage using circularly polarized justified owing to its unique capability providing 3D isotropic rate.

This article presents an experimental and numerical study of short‐fiber‐reinforced rubber sealing composites (SFRC) at different stress amplitudes (1 MPa, 2 3 MPa). The curves the maximum strain varying with number cycles were obtained by fatigue test, damage modes SFRC determined scanning electron microscope. A finite element model (FEM) was established, where fibers distributed randomly stress‐based integrating a bilinear traction‐separation law cohesive zone embedded in fiber/matrix...

ABSTRACT Composites composed of rubber, sepiolite fiber, and resorcinol–formaldehyde latex‐coated aramid short fibers were prepared. Mechanical morphological characterizations carried out. To investigate the effect interfacial debonding on failure behavior short‐fiber‐reinforced rubber composites, a micromechanical representative volume element model for composites was developed. The cohesive zone used to analyze failure. We found that computational results in good agreement with...

The authors demonstrate a method for transverse writing of optical waveguides in crystalline silicon wafer using nanosecond laser with shaped beam profile that is formed by pair cylindrical lenses. In contrast to traditional methods, this avoids forming asymmetric waveguide profiles. Both straight and curved are written nearly circular guide found support single-mode propagation 1550 nm wavelength light. loss also measured.

This article presents an experimental and numerical study on mechanical behavior of sepiolite reinforced rubber sealing composites (SRRC), which are subjected to the transverse tensile loads. A finite element model with fibers in square random distribution is adopted for study. The representative volume elements different fiber fraction established analyzed. successive remeshing strategy employed achieve large deformation SRRC. results show that strength breaking elongation SRRC can be...

Circular craters with diameters of 500 nm are fabricated on the surface fused silica by femtosecond ultraviolet–infrared (UV–IR) pulse trains 0.8 nJ UV energy. damage thresholds at different IR energies and UV–IR delays measured. Diameters depths ablated can be modified adding varying delays. These results demonstrate feasibility nanomachining using short wavelength lasers energy far below normal thresholds.

We demonstrate a structuring method for crystalline silicon using nanosecond laser internal irradiation followed by chemical etching. show dramatic dependence of the etch rate on laser-writing speed. Enhanced isotropic rates laser-induced damage were recently demonstrated with strong acids, but our results add possibility to obtain reduced leading different topographies. Material analyses indicate efficiently produce high-aspect ratio channels, thanks porosities, as well micro-bumps due...

Abstract Under various voltages, the performance variations and compressive flexural failure modes of carbon fiber concrete were investigated. The findings indicate that while general will display a cone upon failure, specimen maintains its integrity under influence voltage, displaying state surface cracking with similar-sized crack spacing. With an increase in voltage level, strength reinforced first rises then falls. at level 15V is 66% higher than without voltage. Similar to test...

Abstract The method of machine test was used in this study to analyze the influence carbon fiber content and voltage strength on impact resistance concrete by recording number impacts fracture failure. results show that as volume increases, specimens increases first then decreases. reaches maximum 0.24 %, calculation formula for beams under different is obtained. However, a state overall reduction action voltage, range obvious, indicating effect has negative concrete.

In this paper, a design sensitivity analysis (DSA) method for fatigue life of 3-D solid structural components mechanical systems with respect to shape parameters is presented. The DSA uses dynamic stress obtained using an analytical approach predict increment due changes; computes the component, including crack initiation and propagation, predicted stress; difference new original at same critical point approximate life. A tracked vehicle roadarm presented in paper demonstrate accuracy...

ABSTRACT The normal and interfacial shear stress distributions with flat fiber tip of short‐fiber‐reinforced rubber matrix sealing composites (SFRC) compared the lag model were investigated by using finite element method (FEM). results indicate that values do not agree those calculated model. effect different geometrical shapes on SFRC was also investigated. under present investigation are flat, semi‐elliptical, hemispherical, circular cone, respectively. show hemispherical transfers load...

Femtosecond laser ablation of gold thin film on the front and backside silicon substrate is investigated, with being focus side for comparison. The experiments are performed using 100 fs pulses delivered through an ultrafast source combined OPA wavelength conversion at 1300 nm. We create a single shot matrix by varying position pulse energy. beam characterized IR imaging technique both substrate. It found that profile experiences little distortion after passing though 1 mm substrate, despite...