Damage Evolution and Acoustic Emission Character of Coalrock under Unloading Condition

The damage failure mechanisms of coalrock under unloading condition during deep mining is different from those under traditional loading condition, starting from the unloading condition position to study the dynamic disaster of coalrock has become a new direction in the disaster study. The rock mechanics electrohydraulic servo test system (MTS815) and acoustic emission system (8CHS PCI 2) are used to study the coalrock deformation damage and acoustic emission (AE) characteristics. The results show that the failure of coalrock under unloading condition exhibits strong brittleness and happens in sudden and is mostly of tensile shear failure type. The evolution curve of cumulative ring down count of acoustic emission can better reflect the coalrock unloading damage evolution process, and the whole unloading failure process can be divided into three stages: the stage of damage weakening, damage stably development stage and the stage of accelerated damage development. During the mining process the confining pressure of the coalrock is unloaded, the coalrock rapidly arrives at the third stage of the whole unloading failure process, and the damage is accumulated rapidly and the fracture failure of coalrok occurred suddenly, then follows the coalrock dynamic disaster.     

Resettling,disconnecting or displacing? Attending to local sociality,culture and history in disaster settings

In many disaster settings, top‐down responses emphasise ‘expert‐led’ solutions that often involve relocating disaster‐affected communities. While the intention might be to move people from harm's way and facilitate recovery, failure to attend to local pre‐disaster circumstances as well as the interplay between power, resilience and vulnerability within and around affected communities often sees resettlement reconfigure as displacement or disconnection. This oversight may even usher in a new phase of dispossession and disadvantage for marginalised groups (particularly in colonial settings). This paper explores experiences in Australia, Japan and Taiwan to reflect on what issues of local sociality, local culture and local resilience need to be attended to in framing ‘better’ disaster responses.     

阴雨寡照灾害对云南烤烟的种植风险预测

阴雨寡照灾害在未来将具有"空间+时间动态性"的变化特征.笔者根据烤烟种植适宜性指标和阴雨寡照等级指标,利用1981-2010年连续30年的逐日气象观测资料和2021-2050年全球气候模式HadGEM2-ES的RCPs排放情景预估结果,结合灾害系统理论,采用多元回归、"距平逼近"插值和栅格运算等方法,分析阴雨寡照灾害对...     

日本冲绳本岛临海民居风景防护林的构建及对中国新民居建设的启示

为加快推进中国农村新民居建设,完善相关配套建设措施,笔者借鉴日本在防灾减灾理论和方法方面处于世界前列,以法律的形式保证规划先行的经验,通过对冲绳本岛相关历史资料分析、民意调查和实地调查,以及福木起源的追溯,福木数量和防护林密度的测算等,论证了福木风景防护林映衬红瓦木造建筑为冲绳典型集落（即村庄、村落）特征。风景防护林的构建源自于村民抵御自然灾害的本能和政府保一方平安的责任意识,最后发展为保护村民生活环境、保障社会安定的基础。同时防护林使冲绳自然环境更显生态美观,促进了旅游业的兴旺,旅游已成为冲绳的支柱产业。     

2010年湖南省农业气象灾害分析及减灾对策

农业气象灾害的发生及其危害是决定于气候异常与农业对象,农业生产不仅有明显的地域性,而且有很强的季节性,农业气象灾害是造成农业生产不稳定的主要因素之一。为此,对2010年对湖南省农业生产影响较大的主要气象灾害,主要有倒春寒、5月低温、洪涝灾害、季节性干旱、8月高温和寒露风等,及各自相应的分布特征和发生规律进行概述。同时,分析了所发生的各种主要农业气象灾害对湖南省农业生产造成的一些不利影响。针对各种主要农业气象灾害对湖南省农业生产产生的种种影响,提出了在农业生产中适宜于湖南省农业减灾防灾的主要对策。认为应分析湖南省主要农业气象灾害发生规律及发展趋势,以期更好的掌握气象灾害在湖南省不同地域的发生规律及对农业生产产生的影响,可通过品种选择与更换、加强田间管理、灾前预警、灾中调控和灾后补救等防灾减灾措施,以提高农业防灾减灾的能力,减轻气象灾害对湖南省农业生产的不利影响,从而为防御农业气象灾害,保障农业生产稳产、增产提供依据。     

基于投影寻踪原理的云南旱灾评估

为了能够对复杂的干旱灾害系统进行灾后评估,反映云南旱灾灾后综合损失,为云南防旱抗旱减灾策略提供理论依据。以云南1950-2009年的旱灾受灾、成灾面积,粮食损失为评价指标,采用投影寻踪法得到分级评估后的综合评价指标。计算结果表明：云南是一个干旱灾害频发且严重的省份,平均2.3年就会出现一次比较严重的旱灾,60年来重大灾害以上发生频次和旱灾损失程度不断上升,给云南经济社会带来了巨大影响,特别是2000年以来的10年期间,发生重大灾害以上次数高达9次,其中重大灾害1次,特大灾害8次。     

Optimal calculation method of stabilizing force for anti slide piles

A new efficient method named matrix method is presented based on the traditional calculation methods of stabilizing force. The method is derived from the thrust force method and designed to address the deficiency of traditional method. It cannot only get the best pile location with minimum stabilizing force when is applied to the design calculation of single row anti slide piles, but also be applied to the optimal calculation of multi row anti slide piles. The cases comparing results show the method is more reasonable. For major projects of landslide control, the combination of matrix method and finite element method can make the result safer and more accurate.     

河套灌区农业生产中的几种主要灾害及减灾对策

在分析河套灌区农业生产中的春潮、低温冷害、盐碱和霜冻等几种主要灾害的发生规律及其对粮油糖三大作物影响的基础上，先后提出了早播、玉米芽栽、浇水压盐及开沟起垅深穴覆膜栽培的减灾对策和措施，经各地试验、示范和大面积推广应用，获得了巨大效益。     

公元1400年以来陇中地区干旱灾害特征

通过对历史文献资料的整理与统计分析,对甘肃陇中公元1400-1999年干旱灾害的等级序列特征、年代际变化、季节变化、空间变化及气候背景进行研究.结果表明:陇中公元1400-1999年共发生旱灾280次,平均每2.14年发生1次.干旱灾害以中度旱灾为主,占旱灾总次数的45.4%,其次是大旱灾,占旱灾总次数的32.1%,特...     

暴发性水土流失防治思路探讨

滑坡与泥石流联系密切.滑坡、泥石流灾害属于水土流失的范畴,是与经常性水土流失相对应的暴发性水土流失类型,其造成的损失巨大,对它的防治要引起足够的重视,要彻底防治必须按照综合防治策略进行,最终效果要用综合效益进行全面评估.