使用於鋪面維修、養護乃至品管之各類非 破壞性試驗(NDT)種類繁多,然就發展之沿革、應 用之廣泛程度以及試驗本身的可信度而言,仍 以動態性撓度檢測方法之運用最為普及。該等 試驗雖擁有快速作業、確保工址完整以及提供 較高的經濟效益等優點,但其以靜態多層彈性 分析(MEA)為計算背景的數據演繹,卻往往不能準 確地反應鋪面結構之動態行為;在回算過程造 成評估誤差,造成工程人員的困擾。本文旨在 針對衝擊力為主的動態撓度試驗,以分析模擬 之方式,檢視並試圖引申試驗數據;希望藉著路 表應力波傳遞之反應頻譜分析,提出較具前瞻 性之應用,做為爾後試驗改良及最佳化的方向 。 Dynamic deflection measurement has been used extensively in highway engineering to estimate the structural capacity of existing pavements. A distinctive problem is often observed while analyzing the measured data with static interpretation procedure. To resolve such problem, displacement response spectra from an impulse load on arbitrary soil sites have been studied analytically. The amplitude and phase spectra as well as the period of attenuating period on surface displacements are found to reveal the possible location of rockbase. Dispersion studies showing the surface propagating velocities versus the wavelengths (or frequencies) permits the estimation of material profiles which include layer moduli, thickness and ground water information. Results of the study suggest a possible "dynamic" way to interpretate the measured data with future instrument optimization.
關聯:
中華民國第七屆鋪面工程學術研討會論文集=Proceedings of the7th National Pavement Engineering Conference, pp.227-237