DL/T1044—2007ICS27.140P55备案号:21251-2007中华人民共和国电力行业标准DL/T1044—2007钢弦式应变计Vibratingwirestrainmeter2007-07-20发布2007-12-01实施中华人民共和国国家发展和改革委员会发布I—2007目次前言··································································································································································Ⅱ1范围······················································································································································12规范性引用文件··································································································································13术语和定义··········································································································································14产品原理、分类及规格······················································································································15技术要求··············································································································································26试验方法··············································································································································37检验规则··············································································································································48标志、包装、运输、储存···················································································································6附录A(规范性附录)钢弦式应变计参数计算方法··········································································7IIDL/T1044—2007前言本标准是根据《国家发展改革委办公厅关于下达2003年行业标准项目补充计划的通知》(发改办工业[2003]873号)要求制定的。本标准附录A为规范性附录。本标准由中国电力企业联合会提出。本标准由电力行业大坝安全监测标准化技术委员会归口并负责解释。本标准起草单位:基康仪器(北京)有限公司、国电自动化研究院。本标准主要起草人:沈省三、刘广林、吴其均、王梅枝。本标准在执行过程中的意见或建议反馈至中国电力企业联合会标准化中心(北京市白广路二条一号,100761)。III—2007钢弦式应变计1范围本标准规定了钢弦式应变计的分类与规格、技术要求、试验方法、检验规则和标志、包装、运输、储存的要求。本标准适用于大坝及其他岩土工程安全监测中测量结构应变的钢弦式应变计。2规范性引用文件下列文件中的条款通过本标准的引用而成为本标准的条款。凡是注日期的引用文件,其随后所有的修改单(不包括勘误的内容)或修订版均不适用于本标准,然而,鼓励根据本标准达成协议的各方研究是否可使用这些文件的最新版本。凡是不注日期的引用文件,其最新版本适用于本标准。GB5603负荷传感器名词术语GB5604负荷传感器试验方法GB6388运输包装收发货标志GB/T50123土工试验方法标准3术语和定义下列术语和定义适用于本标准。3.1频率模数frequencymodulus频率的平方除以1000,一个单位定义为“一个字”。3.2过范围限overrangelimit能够加在钢弦式应变计传感器上不致引起性能永久性变化的被测量的最大值。3.3最小读数mininumreading钢弦式仪器在全量程范围内频率模数变化一个字时被测量的变化值。4产品原理、分类与规格4.1产品原理钢弦式应变计主要由左右端座、钢弦和线圈等组成。当被测结构物发生应变时,应变计左右端座产生相对位移并传递给钢弦,使钢弦受力发生变化,从而改变钢弦的固有频率。测量仪表输出脉冲信号通过线圈激振钢弦并检测出线圈所感应信号的频率,经换算得到被测结构物的应变量,其计算公式见附录A。同时,由钢弦式应变计中的热敏电阻同步测出测IDL/T1044—2007点的温度值。钢弦式应变计的基本原理及结构示意如图1所示。4.2产品分类与规格根据安装方式,钢弦式应变计分成埋入式和表面安装式两类。钢弦式应变计的基本规格和参数见表1。图1钢弦式应变计原理及结构示意图表1钢弦式应变计的基本规格和参数应变范围10−6温度测量范围℃分辨力%F·S弹性模数EgMPa输出频带范围Hz−2000~+1000−1500~+1500−1000~+2000−1500~+1000−1250~+1250−1000~+1500−20~+60≤0.15300~1500400~1300注:F·S为满量程。5技术要求5.1环境条件5.1.1正常工作条件a)环境温度:−20℃~+60℃;b)表面安装式钢弦式应变计应能在0.5MPa水压下正常工作;c)埋入式钢弦式应变计应能在0.5MPa或规定水压下正常工作;d)大气压力:53kPa~106kPa。5.1.2仲裁试验条件a)环境温度:20℃±2℃;b)相对湿度:60%~70%;II—2007c)大气压力:86kPa~106kPa。5.1.3正常试验条件a)环境温度:+15℃~+35℃;b)相对湿度:25%~75%;c)大气压力:86kPa~106kPa。5.2性能参数要求钢弦式应变计的各项性能参数应满足以下要求。5.2.1测量范围钢弦式应变计的测量范围应符合表1的规定。5.2.2分辨力钢弦式应变计的分辨力应符合表1的规定。5.2.3综合误差δ钢弦式应变计的综合误差不大于1.5%F·S,其中:a)非线性度(或拟合误差)δ1不大于1.0%FxS;b)不重复度δ2不大于0.5%F·S;c)滞后δ3不大于1.0%F·S。注:可采用多项式曲线校准拟合,此时钢弦式应变计的拟合误差δ1应不大于0.5%F·S。5.2.4温度测量误差温度测量误差不大于0.5℃。5.3绝缘性能钢弦式应变计芯线与传感器壳体之间的绝缘电阻应大于50MΩ。5.4防水密封性钢弦式应变计在0.5MPa或规定的压力水中,绝缘性能应符合5.3的规定。5.5温度修正误差钢弦式应变计温度修正的校准曲线(因温度变化所引起的应变测值的误差与温度之间的关系曲线),其端基线性度误差以频率模数计,不应超过±0.04%F·S/℃。5.6过范围限钢弦式应变计应能承受测量范围1.05倍的应变能力,当应变恢复至正常测量范围后,在正常工作条件下,钢弦式应变计应变性能应符合5.2的规定。5.7钢弦式应变计的弹性模数Eg钢弦式应变计的弹性模数应符合表1的规定。5.8稳定性在正常试验大气条件下,将钢弦式应变计拉伸至满量程位置静置一个月后,钢弦式应变计性能应满足如下要求:a)绝缘性能应满足5.3的要求;b)最小读数的相对变化量不应超过±2%;c)温度误差应满足5.2.4的要求。IIIDL/T1044—20075.9耐运输颠振性能钢弦式应变计在包装运输时,应能承受最大加速度为5g、历时10min的试验,试验后其性能应满足5.2.1、5.2.2、5.2.3、5.3、5.4的要求。5.10外观钢弦式应变计外观应无变形,外表面无明显划痕,商标、型号等标志清晰,紧固件无松动。6试验方法6.1试验环境6.1.1试验条件除有特殊要求外,试验按5.1.3进行。6.1.2试验设备a)校准仪;b)0级千分表;c)钢弦式仪器测量仪表;d)100V绝缘电阻表;e)恒温箱;f)二等标准水银温度计;g)恒温水槽;h)压力容器;i)振动试验台。6.2性能参数试验将钢弦式应变计固定在专用校准仪上,试验前将钢弦式应变计在满量程范围内预拉压2~3次,将钢弦式应变计按20%满量程位移量分挡,从满量程的下限开始,逐级进给位移至满量程上限,用测量仪表测量其输出并记录每个挡位的测值,如此共进行3个正、反行程的测量。按附录A给出的方法计算钢弦式应变计的分辨力r、最小读数、非线性度(或拟合误差)δ1、不重复度δ2、滞后δ3及综合误差δ等参数。试验结果应符合5.2的规定。6.3绝缘性能试验在正常试验大气条件下,用100V绝缘电阻表测量钢弦式应变计引线电缆与屏蔽线之间的绝缘电阻,应满足5.3的要求。6.4耐水压密封性能试验将钢弦式应变计放置在压力容器中加水压至0.5MPa或规定水压,保持30min,然后用100V绝缘电阻表测量引线与密封壳体之间的绝缘电阻,测量结果应满足5.4的规定。6.5温度修正误差试验及温度测量误差试验将钢弦式应变计固定在一已知线胀系数的夹具上,放入环境试验箱内,将二等标准水银温度计放置在钢弦式应变计附近,分别在0℃、+20℃、+40℃、+60℃进行试验。试验箱以不超过1℃/min的变化率升降温,到达每挡温度并稳定后各保温2h,再测出钢弦式应变计输出的频率模数并同时读出钢弦式应变IV—2007计温度值和二等标准水银温度计读数,按附录A给出的公式计算温度修正系数及误差,试验结果应满足5.5的要求。比较钢弦式应变计温度测值和二等标准水银温度计读数,其温度误差应满足5.2.4的要求。6.6过范围限试验将钢弦式应变计预拉到测量范围上限值的1.05倍,保持1h,恢复到正常的变形范围内按6.2的方法进行性能试验。试验结果应符合5.6的规定。6.7弹性模数Eg试验将钢弦式应变计一端固定,测出此时钢弦式应变计的输出频率模数作为初始值,然后在钢弦式应变计另一端施加2kg轴向力,再测出钢弦式应变计输出频率模数,按附录A给出的公式计算出钢弦式应变计的应变变化量及弹性模数,计算结果应符合5.7的规定。6.8稳定性试验将钢弦式应变计安装在校正仪上,在正常大气试验条件下,拉伸到满量程范围的位置静置一个月后,按6.2、6.3、6.5的方