No failure, moderate failure, severe failure, and slight failure are the four failure modes generalized observed in the dynamic response of the single-layer reticulated dome under vertical impact load on apex. TE (the...No failure, moderate failure, severe failure, and slight failure are the four failure modes generalized observed in the dynamic response of the single-layer reticulated dome under vertical impact load on apex. TE (the time that the end of impact force) and TF (the time that members are broken) are two key times in the failure process. Characteristics of dynamic responses at the two key times are shown in order to make the failure mechanism clear. Then three steps of energy transfer are summarized, i.e. energy applying, energy loss and energy transfer, energy consump-tion. Based on the three steps, energy transfer process for the failure reticulated dome under once impact is introduced. Energy transmissibility and local loss ratio are put forward firstly to obtain EL F(the energy left in the main reticulated dome) from the initial kinetic energy of impactor. More-over, the distribution of failure modes is decided by EL F which leads to the maximum dynamic re-sponse of the reticulated dome, but not by the initial impact kinetic energy of impactor.展开更多
Various technical studies have shown that impact-stiffness modulus values, defined as the ratio of the FWD (falling-weight deflectometer) impact load to its consequent central deflection, can be used to evaluate the...Various technical studies have shown that impact-stiffness modulus values, defined as the ratio of the FWD (falling-weight deflectometer) impact load to its consequent central deflection, can be used to evaluate the PCN (pavement classification number) of a particular flexible or rigid airport pavement, fn a previous study, use was made of the old dynamic stiffness modulus procedure developed by the USCOE (US Army Corps of Engineers), this procedure was correlated with various FWD measurements conducted on several runways and taxiways in Israel, together with in-situ borings and the use of the new COMFAA-3.0 software. The results, obtained only for flexible pavements, were checked against the relevant results of full-scale trafficking tests conducted by the FAA (Federal Administration Aviation) at its National Airport Pavement Test Facility. The present study analyzes new FWD measurements and in-situ borings conducted on additional rigid and all-asphaltic runways and taxiways in Israel in order to formulate an updated correlative equation for these types of pavements. The paper concludes with an updated recommendation for the use of impact-stiffness modulus outputs from FWD measurements in order to determine the PCN of any type of pavement directly on the basis of local experience.展开更多
基金Supported by National Natural Science Foundation of China(No.90715034)
文摘No failure, moderate failure, severe failure, and slight failure are the four failure modes generalized observed in the dynamic response of the single-layer reticulated dome under vertical impact load on apex. TE (the time that the end of impact force) and TF (the time that members are broken) are two key times in the failure process. Characteristics of dynamic responses at the two key times are shown in order to make the failure mechanism clear. Then three steps of energy transfer are summarized, i.e. energy applying, energy loss and energy transfer, energy consump-tion. Based on the three steps, energy transfer process for the failure reticulated dome under once impact is introduced. Energy transmissibility and local loss ratio are put forward firstly to obtain EL F(the energy left in the main reticulated dome) from the initial kinetic energy of impactor. More-over, the distribution of failure modes is decided by EL F which leads to the maximum dynamic re-sponse of the reticulated dome, but not by the initial impact kinetic energy of impactor.
文摘Various technical studies have shown that impact-stiffness modulus values, defined as the ratio of the FWD (falling-weight deflectometer) impact load to its consequent central deflection, can be used to evaluate the PCN (pavement classification number) of a particular flexible or rigid airport pavement, fn a previous study, use was made of the old dynamic stiffness modulus procedure developed by the USCOE (US Army Corps of Engineers), this procedure was correlated with various FWD measurements conducted on several runways and taxiways in Israel, together with in-situ borings and the use of the new COMFAA-3.0 software. The results, obtained only for flexible pavements, were checked against the relevant results of full-scale trafficking tests conducted by the FAA (Federal Administration Aviation) at its National Airport Pavement Test Facility. The present study analyzes new FWD measurements and in-situ borings conducted on additional rigid and all-asphaltic runways and taxiways in Israel in order to formulate an updated correlative equation for these types of pavements. The paper concludes with an updated recommendation for the use of impact-stiffness modulus outputs from FWD measurements in order to determine the PCN of any type of pavement directly on the basis of local experience.