A Fundamental Study to Use Ultrasonic Shear Wave for Quality Control of Concrete

利用超声波剪切波控制混凝土质量的基础研究

• 批准号: 61460178
• 负责人: MATSUFUJI Yasunori
• 金额: $ 4.29万
• 依托单位: Kyushu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-61460178/
• 关键词: Ultrasonic Shear Wave; Concrete; Controll of Exection Schedule; 凝結試験; 非破壊試験; 凝結過程; 動的ずり弾性率; 動的ずり粘性率

In this study, we investigated the properties of concrete by means of travelling ultrasonic pulsed shear wave. The results are summarized as follows.1. Application for testing method for time of settingThe setting time is defined by the characteristics of the dynamic shear modulus-elapsed time curve. It becumes clear that the setting time, varied with water-cement ratio of the mixture, temperature, admixture, and so on, has a significant meaning for exection schedule of concrete work.2. The characteristics of the ultrasonic shear wave travelled through concreteThe power spectrum of the response function of concrete in the early age is limited in the lower frequency range, and the peak frequency dose not agree with that of the operated frequency. It is found that the phenomena is caused by the characteristics of attenuation coefficient of concrete. That is the curves of attenuation coefficient versus frequency have a minimum at each age, and the point shifts to higher frequency with age.3. Application for non-destructive testing methods of concreteIt is found that the compressive strengh of concrete is estimated accurately by it's dynamic shear modulus of cement paste which is calculated by applicating the theory of elasticity of two phase systems The advantage of this method is that compressive strength of concrete is determined independently of mix or age.

在这项研究中，我们研究了混凝土的性能，通过行波超声脉冲剪切波。研究结果如下：1.凝结时间测试方法的应用凝结时间由动态剪切模量-经过时间曲线的特征定义。明确了凝结时间随混合料水灰比、温度、外加剂等因素的变化对混凝土施工进度的重要意义.超声剪切波在混凝土中传播的特性混凝土早龄期响应函数的功率谱仅限于低频范围，峰值频率与工作频率不一致。研究发现，这是由于混凝土材料的衰减特性造成的。即衰减系数随频率的变化曲线在每个年龄段都有一个最小值，且随着年龄的增长，该点向高频方向移动.应用两相体系弹性理论计算水泥浆体的动态剪切模量，可以准确地估算混凝土的抗压强度，其优点是混凝土的抗压强度与配合比和龄期无关。

项目成果

松藤泰典, 河上嘉人, 朝日真司, 渡部嗣道: 日本建築学会大会学術講演梗概集. 467-468 (1987)

Yasunori Matsufuji、Yoshito Kawakami、Shinji Asahi、Tsunomichi Watanabe：日本建筑学会会议学术讲座摘要 467-468 (1987)。

松藤泰典,河上嘉人,渡部嗣道: 日本建築学会研究報告,中国・九州支部,構造系. 第7号・1. 1-4 (1987)

松藤泰典、川上义人、渡边嗣通：日本建筑学会研究报告，中国及九州分会，《结构工程》第 7 期，1. 1-4 (1987)。

Yasunori Matsufuji;Yoshihito Kawakami: Porc. of the 31st Japan Congress on Materials Research.

松藤康典；川上义人：猪肉。

松藤泰典, 河上嘉人, 半田啓一, 小川満弘: 日本建築学会大会学術講演梗概集. 685-686 (1986)

Yasunori Matsufuji、Yoshito Kawakami、Keiichi Handa、Mitsuhiro Okawa：日本建筑学会会议学术讲座摘要 685-686（1986）。

松藤泰典, 河上嘉人, 朝日真司, 渡部嗣道: 日本建築学会大会学術講演梗概集. 465-466 (1987)

Yasunori Matsufuji、Yoshito Kawakami、Shinji Asahi、Tsunomichi Watanabe：日本建筑学会会议学术讲座论文集 465-466 (1987)。