用1-3及2-2连通复合换能器测量冻土  

Measuring frozen soils with composite piezoelectric transducers of 1-3 and 2-2 connectivity

作　　者：袁易全[1] 

机构地区：[1]东南大学无线电系,南京210096

出　　处：《应用声学》2003年第2期39-44,共6页Journal of Applied Acoustics

基　　金：冻土工程国家重点实验室资助项目(批准号9724)

摘　　要：根据冻土弹性波测试要求,研制了一种测试冻上用的500kH2纵波、横波1-3及2-2连通复合超卢换能器,其灵敏度高、频带宽、声阻抗低、波形简单及脉冲波形前沿徒削,亦适用于其它介质力学特性测试。文章介绍了换能结构原理及测量系统特性,实测了不同含水量(7％-25％)及负温(-2℃--20℃)条件下兰州黄土试块的纵、横波声速,获得很高测量精度(10ps级)。500 kHz Composite piezoeloctric broadband ultrasonic transducers with 1-3 and 2-2 connectivity are developed and used for measuring longitudinal wave and transverse wave in frozen soils. The ultrasonic transducers have the characteristics of high sensitivity, wide frequency-band and low acoustic impedance. They are suitable for measuring the mechanical properties of frozen soil. The configuration, the corresponding characteristics and the are presented in this paper. The longitudinal and transverse wave velocities of frozen lanzhou loess are measured under various water contents (7% - 25%) and temperatures (-2 - -20℃) using this system, and the measuring precision is within ±10 ps.

关 键 词：冻土 宽带换能器 纵波 声速 横波 弹性波 力学性能 地基基础 测量 弹性模量 剪切模量 

分 类 号：TU445[建筑科学—岩土工程] TB552[建筑科学—土工工程]