電測法實(shí)驗(yàn)報(bào)告-電阻應(yīng)變片靈敏系數(shù)的測定

1、精選優(yōu)質(zhì)文檔-傾情為你奉上精選優(yōu)質(zhì)文檔-傾情為你奉上專心-專注-專業(yè)專心-專注-專業(yè)精選優(yōu)質(zhì)文檔-傾情為你奉上專心-專注-專業(yè)實(shí)驗(yàn)二 電阻應(yīng)變片靈敏系數(shù)的測定實(shí)驗(yàn)?zāi)康牧私怆娮钁?yīng)變片相對電阻變化與所受應(yīng)變之間的關(guān)系。熟悉靜態(tài)電阻應(yīng)變儀及靜應(yīng)變測量的基本方法。掌握電阻應(yīng)變片靈敏系數(shù)的測定方法。實(shí)驗(yàn)儀器和設(shè)備帶加載裝置的等強(qiáng)度梁裝置，溫度補(bǔ)償塊在梁上沿軸向正反兩面各粘貼3枚應(yīng)變片靜態(tài)電阻應(yīng)變儀三點(diǎn)撓度計(jì)實(shí)驗(yàn)原理原理：Rf：梁的撓度h：梁的厚度l：撓度計(jì)的半跨度因此只需測量電阻應(yīng)變儀的指示應(yīng)變，梁的撓度即可求得該電阻應(yīng)變片的靈敏系數(shù)。實(shí)驗(yàn)步驟安裝等強(qiáng)度梁和撓度計(jì)，將6枚應(yīng)變片按1/4橋接入應(yīng)變儀，將溫

2、度補(bǔ)償塊接入公共補(bǔ)償，力傳感器接入專用測量橋路給梁加卸載2-3次，記錄撓度計(jì)上千分表初始讀數(shù)f0給梁連續(xù)分五級加載，記錄各級載荷大小P、千分表讀數(shù)f和應(yīng)變儀各通道讀數(shù)，記錄。取各應(yīng)變片的總平均值為靈敏系數(shù)K，并計(jì)算相對標(biāo)準(zhǔn)偏差=實(shí)驗(yàn)數(shù)據(jù)h=10mm，l=80mm應(yīng)變片號P(N)f0f計(jì)算()R計(jì)算KK1506.856.8848-93-1863.8732.691006.94144-191-3822.6521507.00240-284-5682.3672007.05320-375-7502.342507.11416-468-9362.25應(yīng)變片號P(N)f0f計(jì)算()R計(jì)算KK2506.856.8

3、893481863.8752.671006.941861443722.581507.002802405602.332007.053713207422.3182507.114664169322.24應(yīng)變片號P(N)f0f計(jì)算()R計(jì)算KK3506.856.88-9348-1863.8752.671006.94-187144-3742.5971507.00-280240-5602.3302007.05-370320-7402.3122507.11-464416-9282.231應(yīng)變片號P(N)f0f計(jì)算()R計(jì)算KK4506.856.88123482465.1253.541006.94245144

4、4903.4031507.003742407483.1172007.054943209883.0872507.1161741612342.966應(yīng)變片號P(N)f0f計(jì)算()R計(jì)算KK5506.856.88-12248-2445.0833.521006.94-244144-4883.3891507.00-373240-7463.1082007.05-490320-9803.0622507.11-615416-12302.957應(yīng)變片號P(N)f0f計(jì)算()R計(jì)算KK6506.856.8894481883.9172.701006.941901443802.6391507.002842405682.3672007.053743207482.3372507.114684169362.250K標(biāo)準(zhǔn)偏差=0.1477有圖可見R誤差：由于橫向效應(yīng)的存在，使得只有在使用條件與標(biāo)定條件相同時(shí)才準(zhǔn)確，應(yīng)變片用于雙向應(yīng)