Discussion of: A study on the application of the parallel seismic method in pile testing

This discussion is based on the paper by Lu et al. (2013) [1]. In this paper, the authors have presented a theoretical study on the PS testing based on the ray path theory and the elastodynamic finite integration technique. This discussion offers some comments on the proposed method for determining the pile length, the ray path of the first P wave arrival for PS testing and analysis results of that paper under discussion.     

Discussion on “Nonlinear seismic response of tall concrete-faced rockfill dams in narrow canyons”

This discussion is based on the paper by Panos Dakoulas [1]. In this paper, the author has presented a comprehensive study on the seismic behavior of tall concrete face rockfill dams in narrow canyons, based on numerical simulation of the staged construction, creep settlements, reservoir impoundment and seismic shaking of the dam. This discussion presents some comments on the input motions for dynamic response analysis, numerical simulated dynamic deformation and the conclusions of that paper, which imply that some aspects need further clarification and/ or improvement.     

Discussion of paper ‘Seismic behavior and modeling of steel reinforced concrete (SRC) walls’ by Xiaodong Ji,Ya Sun,Jiaru Qian and Xinzheng Lu,Earthquake Engineering and Structural Dynamics 2015; 44(6):955–972

The paper under discussion presents a series of quasi‐static tests used to examine the behavior of steel reinforced concrete (SRC) walls subjected to high axial force and lateral cyclic loading. A total of six wall specimens were designed, including five SRC walls and one reinforced concrete (RC) wall. In the ‘Summary’ section of the discussed paper, the authors state that: ‘The use of SRC walls has gained popularity in the construction of high‐rise buildings because of their superior performance over conventional RC walls’. The authors also proposed that, the SRC wall specimens showed increased flexural strength and deformation capacity relative to their RC wall counterpart. The discussion is prompted to rectify some statements and conclusions of the paper under discussion. Copyright © 2015 John Wiley & Sons, Ltd.     

Discussion on ‘a framework for the evaluation of ground motion selection and modification procedures’ by N. Simon Kwong,Anil K. Chopra,and Robin K. McGuire

The paper under discussion proposes a framework to evaluate ground motion selection and modification procedures and illustrates its application for two different procedures as applied to a non‐degrading bilinear inelastic single‐degree‐of‐freedom system. This discussion focuses on providing additional context that this writer feels is needed in relation to both the proposed framework and also its specific application in the paper, which are important for the conclusions made by the authors. Copyright © 2015 John Wiley & Sons, Ltd.     

Discussion on ‘relaxation method for pounding action between adjacent buildings at expansion joint’ by H. Takabatake,M. Yasui,Y. Nakagawa and A. Kishida

The paper under discussion presents a detailed study on the reduction of pounding force on buildings due to expansion joints being filled with rubber. From shake table experiments and numerical simulations, the authors of the paper concluded that the rubber can reduce the maximum pounding force and hence the pounding damage to buildings. However, the writers of this short communication observed some significant issues in the experimental results as well as the numerical simulations. These observations are presented and raise questions about the validity of the results and the subsequent conclusions. Copyright © 2014 John Wiley & Sons, Ltd.     

Response to Professor John Hall's discussion of Hardyniec and Charney's paper, ‘An investigation into the effects of damping and nonlinear geometry models in earthquake engineering analysis’

The discussion presents questions regarding the recommended damping scheme from the discussed paper and provides an alternative recommendation. The discussion also requests further explanation on behavioral differences between models incorporating the P‐delta and corotational approaches that are presented in the paper. Responses to these questions are presented. Copyright © 2016 John Wiley & Sons, Ltd.     

地震调查工作中有关烈度鑑定的一些问题

地震在不同的地质、地形、土质及地下水位等条件下,产生不同的影响。不同地区内各种条件所佔的比重不同,而彼此之间又相互影响;因此在鑑定烈度时,便造成许多困难。但是,如果结合各现象的产生环境,深入分析,全面地与烈度表进行对比,常能得出比较一致的数值。在目前国家建设期间,鑑定6度至10度的地震区域特别     

Discussion of ‘A new approach of selecting real input ground motions for seismic design: The most unfavourable real seismic design ground motions’ by C‐H Zhai and L‐L Xie

This discussion consists of two parts. The first part raises a few comments and questions on the method presented in the above paper. The second part proposes a measure for identifying resonant accelerograms in a set of earthquake records without the need for pre‐processing of the records or inclusion of the structure dynamic analysis. Copyright © 2008 John Wiley & Sons, Ltd.     

Discussion of ‘Seismic behavior of a single‐story asymmetric‐plan buildings under uniaxial excitation’ by A. Lucchini,G. Monti and S. Kunnath

This discussion examines the conclusion reached in the paper that in a single‐story asymmetric‐plan building the maximum displacement demand in the different resisting elements is reached for the same deformation configuration of the system and that the resultant of the seismic forces producing such demand is located at the center of resistance. It is shown that this conclusion is valid only for the particular model studied and cannot be generalized. Copyright © 2009 John Wiley & Sons, Ltd.     

威海市区地震地质研究

张家口－渤海－威海断裂带通过威海市区，加强该断裂带的研究对城市规划和建设具有重要意义。利用十几年来取得的地震、水文、工程地质资料，对该断裂进行了初步分析，认为其具有明显的新活动特征。结合已取得的历史地震资料，对本区的地震地质条件有了较深的认识     

绝对重力测量的进展及其研究动向

本文介绍了绝对重力仪和绝对重力测量的进展,提供了最近十几年来国际上绝对重力测量进行比对的结果。根据有关先进国家的研究计划,分析和讨论了绝对重力测量的发展趋势。     

Discussion of “The effect of energy concentration of earthquake ground motions on the nonlinear response of RC structures” by H. Cao,M.I. Friswell

This discussion raises a few comments and questions on the paper by Cao and Friswell [Cao H, Friswell MI. The effect of energy concentration of earthquake ground motions on the nonlinear response of RC structures. Soil Dyn Earthquake Eng 2009; 29: 292–9.]. The authors consider an interesting problem on seismic response analysis of nonlinear structures. Specifically, the study examines the implication of the energy concentration of the adopted ground acceleration record on the nonlinear response of reinforced concrete structures. The paper employs the wavelet transform to characterize the energy content of the ground acceleration in time and frequency domains.     

Discussion of ‘Modelling viscous damping in nonlinear response history analysis of buildings for earthquake excitation’ by Anil K. Chopra and Frank McKenna

This discussion deals with recommendations in the paper on appropriate damping formulations for use in nonlinear response history analysis of buildings. Concern over potentially excessive damping forces and moments should extend beyond the damping moments produced by the stiffness proportional part of Rayleigh damping that corresponds to rotational springs used to explicitly model plastic hinges. The key to an appropriate damping formulation for nonlinear analysis is a realistic mechanism that allows all damping forces and moments to be meaningfully assessed. Then features can be added to keep these forces and moments within reasonable bounds. Copyright © 2016 John Wiley & Sons, Ltd.     

地电场震前变化的探讨

地电场的地震预报研究目前处于摸索探讨阶段。本文主要利用西北地区的一些数字化观测资料对地电场的震前变化进行分析,并就地电场的预报提出一些看法和建议。     

The concentration of negative ions of oxygen and its combinations in the ionosphere

Summary There are some processes in the ionosphere which were or could be explained by means of negative ions, such as sunrise effects, echo duration anomalies of meteor train radar observations and others. Therefore the concentration of negative ions was computed in this paper for some electron density distributions in a stationary quasineutral model of the undisturbed ionosphere. Such an investigation seems necessary because in the last few years laboratory experiments and theoretical calculations give some improved values of attachment and detachment coefficients. The density of negative ions at 12 00 local time and at 00 00 local time in dependence on height was calculated. A discussion of these values shows that negative ions must be considered only in the lower ionosphere at most up to 130 km. This agrees well with the conclusions derived from the observations. By using the values derived in this paper it seems possible to explain some results of ionosphere measurements such as those concerning sunrise effects and others.Mitteilung Nr. 124.     

Calculating Internal Avalanche Velocities from Correlation with Error Analysis

Velocities inside avalanches have been calculated for many years by calculatingthe cross-correlation between opto-electronic sensors using a method pioneered by inlinecite Nishimura et al. and Dent et al. Their approachhas been widely adopted but there has been little discussion of the optimal designof such instruments and the best analysis techniques. This paper discusses some ofthe different sources of error that arise and how these can be mitigated. A statisticalframework that describes such instruments is developed and used to quantify the errors.     

气枪震源在地球深部结构探测中的应用研究进展

介绍了气枪震源的发展历史、工作原理、激发参数、性能指标,及气枪震源的最新发展动态.由于气枪震源的优越性,使得气枪震源成为新兴的、环保的、绿色的人工震源,在地球物理学中得到迅速推广和广泛应用,如国外的LARSE和SIGHT计划,及国内的南海东北部海陆联合勘探计划,都是利用气枪震源进行深部地球物理探测的成功实例.通过对气枪震源的容积能量、激发频率、沉放深度等的分析和讨论,探讨气枪震源在地球深部结构探测中的进一步应用.     

南宁9·13地震传言的公共危机分析与启示

介绍了2008年南宁9.13地震传言的处置过程,并运用公共危机理论剖析了此次地震传言的潜在危害性,探讨了政府主管部门应对此次地震传言的方法,得出了一些值得借鉴的启示。     

一种有苗头的临震前兆——对水平摆地倾仪波动异常的探索

六年来,我们用无阻尼水平摆地倾仪,在1.7秒—5秒的周期范围内,在一系列的强震发生前,分别记录到了一种明显的波动异常。並用它对不少的强震,诸如1976年8月16日松潘7.2级地震、1976年11月7日盐源6.9级地震,作了比较好的临震预报。实践证明这是一种有苗头的临震前兆。本文是对六年来探索工作的一个总结,並对其成因机制作了初步的探讨。     

低应变测桩承载力的理论与应用

本文简述了确定单桩承载力的各种方法及其适用性，着重论述了低应变测桩承载力的理论及影响因素以及用低应变测桩承载力的适用条件。