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(1 安陽工學(xué)院土木與建筑工程學(xué)院, 安陽 455000;2 安陽市結(jié)構(gòu)檢測與加固工程技術(shù)研究中心, 安陽 455000)

摘要: 為研究混凝土壓應(yīng)力水平對(duì)超聲聲速的影響,考慮了混凝土強(qiáng)度等級(jí)及齡期兩種因素,制作了 C20、C30、C35、C40、C45 五種強(qiáng)度的混凝土標(biāo)準(zhǔn)立方體試塊. 在齡期為 7、14、21、28、35d 時(shí),分別對(duì)試塊進(jìn)行不同受壓狀態(tài)下的超聲檢測試驗(yàn). 結(jié)果表明:混凝土在受壓狀態(tài)下超聲聲速隨壓應(yīng)力增加呈分段線性減小趨勢. 根據(jù)應(yīng)力?聲速曲線變化規(guī)律,提出了三拐點(diǎn)四線性段假定,建立了混凝土受壓狀態(tài)下應(yīng)力?聲速理論模型;該模型可以將壓應(yīng)力狀態(tài)下混凝土結(jié)構(gòu)超聲檢測得到的超聲聲速修正為無應(yīng)力狀態(tài)下的超聲聲速. 經(jīng)試驗(yàn)驗(yàn)證,該模型誤差較小. 該研究結(jié)果揭示了混凝土受壓狀態(tài)下的超聲傳播特性,為拓展超聲檢測范圍和提高超聲檢測評(píng)定結(jié)果精度提供了參考依據(jù).

關(guān)鍵詞: 混凝土檢測; 超聲法; 壓應(yīng)力水平; 混凝土強(qiáng)度; 受壓狀態(tài)

中圖分類號(hào):TU317+. 8 文獻(xiàn)標(biāo)志碼:A 文章編號(hào):1002?848X(2022)16?0101?06

DOI:10. 19701 / j. jzjg. 20211079

Research on the influence of concrete compressive stress level on ultrasonic sound velocity

SHI Zhiqiang1,2

(1 School of Civil and Architectural Engineering, Anyang Institute of Technology, Anyang 455000, China; 2 AnyangCity Structure Testing and Reinforcement Engineering and Technology Research Center, Anyang 455000, China)

Abstract: In order to study the influence of concrete compressive stress level on ultrasonic sound velocity, the concretestandard cube blocks with strength of C20, C30, C35, C40 and C45 were made by considering two factors of concretestrength grade and age. When the age was 7, 14, 21, 28d and 35d, the blocks were tested under different compressionconditions by ultrasonic testing. The results show that the ultrasonic sound velocity of concrete under compression decreasespiecewise linearly with the increase of compressive stress. According to the changing law of the stress?sound velocity curve,the assumption of three inflection points and four linear segments was put forward, and a theoretical model of stress?soundvelocity of concrete under compression was established. The model can be used to modify the ultrasonic sound velocity ofconcrete structure under compression to that under non?stress state. The experimental results show that the error of thismodel is small. The research results reveal the ultrasonic propagation characteristics of concrete under compression, andprovide a reference for expanding the range of ultrasonic testing and improving the accuracy of ultrasonic testing andevaluation results.

Keywords:concrete detection; ultrasound method; compressive stress level; concrete strength; compression condition

∗河南省科技計(jì)劃重點(diǎn)攻關(guān)資助項(xiàng)目( 212102110216、152102310205、132102310334),河南省高等學(xué)校重點(diǎn)科研項(xiàng)目資助(17A560015).

第一作者:石志強(qiáng),碩士,副教授,主要從事土木工程結(jié)構(gòu)及其檢測方面的研究,Email:37905344@ qq. com.

[引用本文] 石志強(qiáng). 混凝土壓應(yīng)力水平對(duì)超聲聲速的影響研究[ J]. 建筑結(jié)構(gòu),2022,52(16):101?106. SHIZhiqiang. Research on the influence of concrete compressive stress level on ultrasonic sound velocity [ J]. BuildingStructure,2022,52(16):101?106.