Development of Dynamic Portable Graders for Structural Lumber Using Tapping Method

攻丝法动态便携式结构材平地机的研制

• 批准号: 01860021
• 负责人: SOBUE Nobuo
• 金额: $ 2.88万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research (B).
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01860021/
• 关键词: Portable MOE grader; Tapping method; Longitidinal vibration; Flexural vibration; Structural lumber; タッピング法; 実大構造材

The object of this project was directed to the development of the portable dynamic graders which are used for the non-destructive strength evaluation of structural lumber.1. The following systems were developed : (1) An automated high-speed system which was composed of an Fast Fourier Transformation (FFT) spectrum analyzer and a 16-bit personal computer, (2) A pocket Young's-modulus tester which was composed of a counter LSI and logic ICs, (3) An automated system which was composed of a 16-bit personal computer and a commercial A/D converter board, and (4) A system which was composed of a pocket computer and a commercial A/D converter board.2. In situ application test of the automated system : The automated system using a FFT spectrum analyzer was transported to lumber mills and a forest-side log yard in order to examine the applicability and to obtain the data on the physical parameters of 2X4 lumber (S-P-F) and structural lumber of sugi and hinoki for the traditional Japanese wooden house. The maximum measuring speed was 100 pieces of lumber per an hour in the case of structural lumber. The rate-determining step of the measurement was the changing of specimens by human handling. In the case of logs, the weight measurement should be improved.3. Numerical analysis of the flexural vibration theory of tapered beam was made to adopt the flexural vibration technique to logs by using the transfer matrix method. The results made the application of the vibration theory of the beam with homogeneous cross-section possible.4. Knowledge base of the physical properties of structural timbers which was stored during in situ test was use to examine the algorism of the non-destructive strength prediction of structural timber. MOE prediction by the resonance frequency and the multiple regression model were studied.

本项目的目标是开发便携式动态平地机，用于结构木材的无损强度评估。开发了以下系统：(1)由快速傅里叶变换(FFT)频谱分析仪和16位个人计算机组成的高速自动系统；(2)由计数器LSI和逻辑IC组成的袖珍杨氏模数测试仪；(3)由16位个人计算机和商用A/D转换板组成的自动化系统；(4)由袖珍计算机和商用A/D转换板组成的系统。自动化系统的现场应用测试：使用快速傅立叶变换频谱分析仪的自动化系统被运送到木材厂和林边伐木场，以检验其适用性，并获得日本传统木屋的2X4木材(S-P-F)和杉木和希诺基结构木材的物理参数数据。对于结构材，最大测量速度为每小时100块木材。测量的速率决定步骤是通过人工操作改变样品。对于原木，应改进重量测量。利用传递矩阵法对测井曲线采用弯曲振动技术，对变截面梁的弯曲振动理论进行了数值分析。研究结果为均匀截面梁振动理论的应用提供了可能。利用现场测试过程中存储的结构木材物理性能知识库，对结构木材无损强度预测的算法进行了检验。研究了利用共振频率和多元回归模型预测弹性模量的方法。

项目成果

Sobue, Nobuo: "Correction Factors of the Resonance Frequency for Tapering and Shear Deformation of a Log in Flexural Vibration." Mokuzai Gakkaishi. 36. 760-764 (1990)

Sobue，Nobuo：“弯曲振动中原木锥度和剪切变形的共振频率的校正因子。”

祖父江信夫: "たわみ振動の固有振動数に対する丸太の細りの補正係数" 木材学会誌. (1990)

Nobuo Sobue：“偏转振动固有频率的原木稀疏校正系数”日本木材学会杂志（1990）。

祖父江 信夫: "Correction Factors of the Resonance Freguency for Tapering and shear Deformation of a Log in Flexural Vibration" 日本木材学会誌. 36. 760-764 (1990)

Nobuo Sobue：“弯曲振动中原木锥度和剪切变形的共振频率的校正因子”日本木材学会杂志 36. 760-764 (1990)。

祖父江 信夫: "振動現象を利用した実大構造材の弾性率測定" 平成元年度文部省科学研究費(試験研究)資料, 57 (1989)

总江信夫：《利用振动现象测量全尺寸结构材料的弹性模量》文部科学省科学研究补助金（实验研究）材料，1989年，57（1989）

Sobue, Nobuo: "MOE measurement of structural timbers by using vibration technique." As report of the Grant-in-Aid for Developmental Scientific Research B(2). (1989)

Sobue, Nobuo：“使用振动技术对结构木材进行 MOE 测量。”