本文選題：損傷識別 + 動力荷載作用　； 參考：《湖南大學(xué)》2013年碩士論文

【摘要】：工程結(jié)構(gòu)在地震等強(qiáng)動力荷載作用下的損傷識別和性能評估是災(zāi)后救援、安全評估和恢復(fù)重建中所需解決的關(guān)鍵問題。在強(qiáng)動力荷載作用下，工程結(jié)構(gòu)的損傷發(fā)生發(fā)展過程是一個(gè)典型的非線性過程，以往基于結(jié)構(gòu)測量和特征值提取的以結(jié)構(gòu)剛度降低來描述結(jié)構(gòu)損傷的反分析方法嚴(yán)格來講僅適用于線性動力系統(tǒng)，且結(jié)構(gòu)的非線性特征具有明顯的差異性，因此，研究具有一般意義的結(jié)構(gòu)非線性行為識別方法對工程結(jié)構(gòu)在動力荷載作用下?lián)p傷的定性和定量評估具有重要意義。 基于上述背景，本文將結(jié)構(gòu)的非線性恢復(fù)力作為描述結(jié)構(gòu)非線性行為的直接指標(biāo)進(jìn)行識別，提出和發(fā)展了具有一般意義的多自由度非線性結(jié)構(gòu)的損傷識別方法，為結(jié)構(gòu)在動力荷載作用下?lián)p傷的發(fā)生發(fā)展過程進(jìn)行監(jiān)測以及對結(jié)構(gòu)耗能進(jìn)行定量評估提供了新方法。主要研究內(nèi)容如下： 1、在理論方法中，提出了一種基于二重切比雪夫多項(xiàng)式的多自由度結(jié)構(gòu)非線性恢復(fù)力的識別方法，該方法能夠在結(jié)構(gòu)質(zhì)量和結(jié)構(gòu)非線性特性均未知的條件下，，對體系的非線性恢復(fù)力、結(jié)構(gòu)的質(zhì)量分布及其非線性特性進(jìn)行有效地識別�；诮Y(jié)構(gòu)激勵及其相應(yīng)的響應(yīng)時(shí)程，利用最小二乘優(yōu)化算法和牛頓第三定律，從結(jié)構(gòu)動力平衡方程出發(fā)，分別討論了該識別方法在結(jié)構(gòu)激勵完整和非完整兩種情況下的具體實(shí)現(xiàn)過程。 2、在數(shù)值模擬中，利用達(dá)芬系統(tǒng)、基于形狀記憶合金(shape memory alloy，SMA)材料的阻尼器(簡稱SMA阻尼器)理想雙旗形系統(tǒng)、和基于磁流變阻尼器(Magneto-Rheological damper，簡稱MR阻尼器)的滯回系統(tǒng)三類非線性模型來模擬結(jié)構(gòu)的非線性行為，分別考慮無噪聲影響和6%環(huán)境噪聲水平影響，并與既有的基于冪級數(shù)多項(xiàng)式模型的識別方法進(jìn)行了對比，且在多自由度數(shù)值算例模型中引入多個(gè)非線性模型來模擬工程結(jié)構(gòu)可能發(fā)生的多處損傷，考慮不同的激勵位置，驗(yàn)證了該識別方法的有效性。 3、在一個(gè)四層框架模型中分別安裝MR阻尼器和SMA阻尼器來模擬結(jié)構(gòu)的非線性行為，利用力錘施加沖擊荷載，對該多自由度非線性結(jié)構(gòu)開展了不同激勵方式下的動力實(shí)驗(yàn)。僅基于結(jié)構(gòu)激勵及其響應(yīng)的時(shí)域信號，通過與實(shí)測結(jié)果的對比分析，進(jìn)一步驗(yàn)證了本文提出的基于二重切比雪夫多項(xiàng)式的非線性恢復(fù)力識別法對結(jié)構(gòu)非線性恢復(fù)力、MR阻尼力和SMA阻尼器恢復(fù)力的識別效果。
[Abstract]:Damage identification and performance evaluation of engineering structures under earthquake and other strong dynamic loads are the key problems to be solved in post-disaster rescue, safety assessment and reconstruction. Under the action of strong dynamic load, the damage and development process of engineering structure is a typical nonlinear process. In the past, the inverse analysis method based on structural measurement and eigenvalue extraction used to describe structural damage by structural stiffness reduction is strictly applicable to linear dynamic systems, and the nonlinear characteristics of structures are obviously different. It is of great significance to study the identification method of nonlinear behavior of structures with general significance for the qualitative and quantitative evaluation of the damage of engineering structures under dynamic loads. Based on the above background, the nonlinear restoring force of the structure is regarded as the direct index to describe the nonlinear behavior of the structure, and the damage identification method of the multi-degree-of-freedom nonlinear structure with general significance is proposed and developed. It provides a new method for monitoring the occurrence and development of structural damage under dynamic loads and for quantitatively evaluating the energy dissipation of structures. The main contents of the study are as follows: 1. In the theoretical method, a method based on double Chebyshev polynomials is proposed to identify the nonlinear restoring force of multi-degree-of-freedom structures. The method can be used to identify the nonlinear restoring forces of multi-degree-of-freedom structures under the condition that both the mass and the nonlinear characteristics of the structures are unknown. The nonlinear restoring force, mass distribution and nonlinear characteristics of the system are recognized effectively. Based on the structural excitation and its corresponding response time history, using the least square optimization algorithm and Newton's third law, starting from the structural dynamic equilibrium equation, The realization process of the method is discussed in the case of structural excitation integrity and nonholonomic respectively. 2. In the numerical simulation, the ideal double-flag damper (SMA damper) based on shape memory alloy (SMA) material is used in the numerical simulation. And three kinds of nonlinear models based on Magneto-Rheological dampers (Mr dampers) are used to simulate the nonlinear behavior of the structures, taking into account the influence of no noise and 6% ambient noise level, respectively. Compared with the existing identification methods based on the power series polynomial model, several nonlinear models are introduced into the multi-degree of freedom numerical example model to simulate the possible multiple damage of engineering structures, and different excitation positions are considered. The validity of the method is verified. 3. Mr dampers and SMA dampers are installed in a four-story frame model to simulate the nonlinear behavior of the structure. The dynamic experiments of the multi-degree-of-freedom nonlinear structure under different excitation modes are carried out by using the force hammer to exert the impact load. Based only on the structural excitation and its response, the time-domain signal is compared with the measured results. The recognition effect of nonlinear restoring force based on double Chebyshev polynomials on nonlinear restoring force and Mr damping force of structure and SMA damper is further verified.
【學(xué)位授予單位】：湖南大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2013
【分類號】：TU317;TU311.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 吳波,孫科學(xué),李惠,唐衛(wèi)勝;形狀記憶合金力學(xué)性能的試驗(yàn)研究[J];地震工程與工程振動;1999年02期

2 李惠,毛晨曦;形狀記憶合金(SMA)被動耗能減震體系的設(shè)計(jì)及參數(shù)分析[J];地震工程與工程振動;2001年S1期

3 周強(qiáng),瞿偉廉;磁流變阻尼器的兩種力學(xué)模型和試驗(yàn)驗(yàn)證[J];地震工程與工程振動;2002年04期

4 李惠,毛晨曦;新型SMA耗能器及結(jié)構(gòu)地震反應(yīng)控制試驗(yàn)研究[J];地震工程與工程振動;2003年01期

5 陳雋,徐幼麟,李杰;Hilbert-Huang變換在密頻結(jié)構(gòu)阻尼識別中的應(yīng)用[J];地震工程與工程振動;2003年04期

6 薛偉辰;鄭喬文;劉振勇;李杰;;結(jié)構(gòu)振動控制智能材料研究及應(yīng)用進(jìn)展[J];地震工程與工程振動;2006年05期

7 孫鴻敏,李宏男;土木工程結(jié)構(gòu)健康監(jiān)測研究進(jìn)展[J];防災(zāi)減災(zāi)工程學(xué)報(bào);2003年03期

8 廖富魁;切比雪夫多項(xiàng)式降階技術(shù)在設(shè)計(jì)數(shù)字濾波器中的應(yīng)用[J];四川兵工學(xué)報(bào);1998年01期

9 黃俊欽,劉整社;多項(xiàng)式模型方次與參數(shù)同時(shí)估計(jì)的正交化法[J];航空學(xué)報(bào);1987年01期

10 史麗萍,孫寶元,于浩洋;切比雪夫多項(xiàng)式回歸分析方法在測量數(shù)據(jù)處理中的應(yīng)用[J];黑龍江大學(xué)自然科學(xué)學(xué)報(bào);2003年02期

相關(guān)博士學(xué)位論文 前1條

1 賀佳;結(jié)構(gòu)非線性行為及動力荷載時(shí)域識別研究[D];湖南大學(xué);2012年

本文編號：1918126