Bridge testing project and testing method

The bridge inspection program includes bridge dynamic characteristic modal parameter test and bridge dynamic response test, and the method of inspection can use dynamic test method.

Generally speaking, the inspection program mainly includes bridge dynamic characteristic modal parameter test (frequency, vibration shape, damping ratio) and bridge dynamic response test (dynamic deflection, dynamic stress, acceleration, impact coefficient). Determination of the intrinsic frequency of the bridge structure is relatively simple, only the first-order frequency of the structure, the structure is more complex dynamic analysis, should also consider the second, third and higher order frequency.

The intrinsic frequency of the bridge can be determined directly from the peak value on the power spectrogram, the time-domain course curve or its autocorrelation diagram recorded by the test system. From the fundamental frequency can also be deduced from the dynamic stiffness of the load-bearing structure. Bridge inspection dynamic load test is the basic test of the evaluation method of power determination, the content is mainly structural dynamic characteristics and dynamic load response test and analysis, measurement of the main part of the structural dynamic effect of the largest component of the dynamic stress and dynamic deformation of the control cross-section.

Bridge testing is a requirement for quite detailed work, bridge testing methods are many, the inspector should not only have a wealth of practical field experience, but also have a solid theoretical foundation as a guide. Only by fully combining theory and practice, coupled with the tacit cooperation between the conductor and the various test personnel, in order to do a good job of testing and obtain satisfactory data to make an accurate assessment.

Bridge inspection notes

1, view the bridge layout form this is the most important, some inspectors engaged in inspection work for more than 20 years still do not understand this reasoning, it is evident that he has not been enough attention to the design intent and fully understand.

2, review the bridge parts of the pile number is correct. Some of the bridge layout, the bridge start and end pile number is often marked wrong, must be through the starting pile number and the length of the bridge parts to check whether the end of the bridge pile number is correct. Only when the pile number is correct can the pile number corresponding to the axis of the pile be deduced.

3, each axis position pile number determination, such as inclined bridge deck pile arrangement form is double row pile, determine the cover beam centerline pile number is the key, so as to calculate the specific coordinates of each pile position.

4, the determination of the margins of this issue is also very important, the bridge is orthogonal or diagonal, is the location of piers or abutments, the location of the settlement joints, in particular, to look carefully, the illustration of the settlement joints whether the width of the label.