## 身体倾斜与雪板变形——高山滑雪刻滑回转中的力学1)

*北京理工大学宇航学院力学系, 北京 100081

## INCLINED BODY AND FLEXED BOARD—MECHANICS IN CARVING TURN OF ALPINE SKIING1)

WAN Chao,*,2), YI Kaijun*, HU Jing, LUO Kai*, WANG Ning

*Department of Mechanics, School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China

China Media Group, Beijing 100020, China

 基金资助: 1)教育部产学合作协同育人项目(202102079018)教育部第二批新工科研究与实践项目(E-SXWLHXLX20202602)

Abstract

Alpine skiing is a traditional Winter Olympics event. The carving turn technique in this competition contains a lot of mechanics phenomena, which is very suitable as a practical case to be used in mechanics course and in the introduction of popular science. In this paper, D'Alembert's principle and beam's bending theory are used to study the two key characteristics of alpine skiers' body inclination and snowboard deformation during carving slalom, respectively. The results indicate close relationship between the carving outcome and body inclination/snowboard deformation. The mechanics model in this paper is simple and easy to understand, and it contains clear knowledge points. It can be used as a teaching case for mechanics courses to cultivate students' practical ability for solving practical problems, and it can also be used as a popular science case to demonstrate the application of mechanics in people's daily life.

Keywords： carving; alpine skiing; D'Alembert's principle; beam's bending; teaching case; popular science

WAN Chao, YI Kaijun, HU Jing, LUO Kai, WANG Ning. INCLINED BODY AND FLEXED BOARD—MECHANICS IN CARVING TURN OF ALPINE SKIING1). Mechanics in Engineering, 2022, 44(2): 479-483 DOI:10.6052/1000-0879-22-094

## 2 身体倾斜——理论力学实例

${F}_{{\rm I}C} =\frac{mv_{{\rm c}}^{2} }{\rho }$
${M}_{{\rm I}C} =J_{{C}} \alpha$

### 图2

$x_{C} G-y_{C} F_{{\rm I}C} +F_{{\rm N1}} d={\bf 0}$

$x_{C} G-y_{C} F_{{\rm I}C} ={\bf0}$

$\frac{mv_{{\rm c}}^{2} }{\rho }y_{C} =x_{C} mg$

$F_{{\rm N1}} -F_{{\rm I}C} \sin \beta -G\cos \beta ={\bf 0}$

$F_{{\rm N1}} =\frac{mg}{\cos \beta }$

## 3 雪板变形——材料力学实例

$\frac{1}{\rho_{{\rm beam}} }=\frac{M}{EI}$

### 图4

$\omega=\left\{\begin{array}{l}-\frac{F(l-a) x}{6 E I l}\left(2 a l-x^{2}-a^{2}\right) \\0 \leqslant x \leqslant a \\frac{F(l-a)}{6 E I l}\left[\frac{l}{l-a}(x-a)^{3}+\right. \\\left.\left(2 a l-a^{2}\right) x-x^{3}\right] \\a \leqslant x \leqslant l\end{array}\right.$
$\theta=-\frac{F a(l-a)(2 l-a)}{6 E I l}$

## 参考文献 原文顺序 文献年度倒序 文中引用次数倒序 被引期刊影响因子

Wu jinping, Zhao Liang, Sun Dong, et al.

Influence factors for competitive performance of Alpine skiers in the view of biomechanics

Journal of Medical Biomechanics 2021, 36(4):502-509 (in Chinese)

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Biomechanical aspects of new techniques in alpine skiing and ski-jumping

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There have been considerable changes in equipment design and movement patterns in the past few years both in alpine skiing and ski-jumping. These developments have been matched by methods of analysing movements in field conditions. They have yielded new insights into the skills of these specific winter sports. Analytical techniques have included electromyography, kinetic and kinematic methods and computer simulations. Our aim here is to review biomechanical research in alpine skiing and ski-jumping. We present in detail the techniques currently used in alpine skiing (carving technique) and ski-jumping (V-technique), primarily using data from the authors' own research. Finally, we present a summary of the most important results in biomechanical research both in alpine skiing and ski-jumping. This includes an analysis of specific conditions in alpine skiing (type of turn, terrain, snow, speed, etc.) and the effects of equipment, materials and individual-specific abilities on performance, safety and joint loading in ski-jumping.

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