远海工程的施工测量放样

随着GPS定位技术的发展,目前国内一些远海特大型工程,主要是特大型桥梁的建设正迅速展开。远海工程的测量定位都得依靠GPS定位技术。由于海上施工放样的特殊性,在针对远洋工程施工的特点和技术要求的基础上,进行了施工放样方案选择和精度分析。通过在杭州湾跨海大桥的实践,摸索出在GPS静态测量的基础上用全站仪等常规测量仪器进行施工放样的方法,它能保证测量放样工作的速度和测量放样的精度。     

Uncertainty analysis of strain modal parameters by Bayesian method using frequency response function

Structural strain modes are able to detect changes in local structural performance, but errors are inevitably intermixed in the measured data. In this paper, strain modal parameters are considered as random variables, and their uncertainty is analyzed by a Bayesian method based on the structural frequency response function (FRF). The estimates of strain modal parameters with maximal posterior probability are determined. Several independent measurements of the FRF of a four-story reinforced concrete frame structural model were performed in the laboratory. The ability to identify the stiffness change in a concrete column using the strain mode was verified. It is shown that the uncertainty of the natural frequency is very small. Compared with the displacement mode shape, the variations of strain mode shapes at each point are quite different. The damping ratios are more affected by the types of test systems. Except for the case where a high order strain mode does not identify local damage, the first order strain mode can provide an exact indication of the damage location.     

GPS静态测量在杭州湾跨海大桥中的应用

简述GPS静态测量的基本概念及其特性,根据GPS静态测量在杭州湾跨海大桥工程建设中的实际应用,探讨GPS静态测量在远海大型工程中具体应用的基本模式。     

远海工程的施工测量放样

根据GPS静态测量以及全站仪在杭州湾跨海大桥工程施工放样中的实际应用,探讨远海大型工程施工测量放样的具体应用的基本模式。