基于豆石混凝土的异型锚杆承载力试验研究

为了提高锚杆的承载力，采用小颗粒豆石混凝土替代水泥砂浆作为锚固剂，并在锚杆锚固段增加锚刺，进行了锚杆承载力拉拔试验，重点研究了异型锚杆承载力与锚刺层数、豆石混凝土强度、试块尺寸之间的关系。结果表明：改变锚杆杆体结构型式对提高其承载力效果显著，单层锚刺锚杆承载力是光杆的1.2?1.7倍;在锚刺强度一定条件下异型锚杆承载力与豆石混凝土强度呈非线性关系，但随着混凝土强度的增大承载力提升幅度越来越小；单层锚刺条件下，锚杆承载力随着试块尺寸增大而增大，说明锚刺强度一定时其承载力与混凝土厚度正相关。

Automatic wavefront reconstruction on single interferogram with spatial carrier frequency using Fourier transform

Optical interferometry can be applied to obtain the wavefront phase and reconstruct the three-dimensional wavefront by analyzing interference fringes. Single interferogram analysis based on two-dimensional Fourier transform is proposed. This method just needs to acquire and analyze single interferogram to solve the wavefront phase. Compared with phase-shift method, Single interferogram analysis can reduce experiment cost and the limitation of measuring e nvironment like vibration, airflow and noise, and meet the requirement of real-time and dynamic interferometry. Because the wavefront phase information is included in the carrier frequency components of single interferogram, an image edge detection method is used to automatically extract the center and boundary of the first-order carrier component of the spatial spectrum of the interferogram in the frequency domain.