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1.
通过现场爆破振动监测,获得了煤矿综采面硬岩段深孔松动爆破地震波的衰减规律;采用sym5小波基对典型振动信号进行分解,研究爆破地震波的能量分布特征。结果表明:深孔松动爆破振动的持续时间为150 ms左右,振动速度三方向分量中径向分量最大;主振频率分布在40~60 Hz,能量主要集中在30~65 Hz的频带范围,存在强烈爆破振动造成岩石崩落对管线设备造成危害的可能。根据衰减规律,得到深孔爆破的单段最大允许药量,提出施工时控制单段最大药量和加强爆破炮孔周围防护,保证了施工安全。  相似文献   

2.
工程爆破中的建筑物振动监测   总被引:20,自引:0,他引:20       下载免费PDF全文
首先就工程爆破施工中建筑物的振动监测问题进行了较为全面的介绍,从振动速度、频率、地基土壤性质等方面分析了爆破地震波引起结构物破坏的原因,并结合工程实例,就结构物的振动数据采集提出了见解.研究认为,建筑物的安全阈值应根据结构最易发生破坏的部位所采集的数据为标准来进行判断,而不是根据结构物地面所采集的数据来确定.  相似文献   

3.
罗沙隧道洞口爆破振动研究   总被引:2,自引:2,他引:0  
以罗沙隧道为研究背景,进行了高地应力下硬岩隧道洞口爆破开挖振动监测试验。对振动数据进行了归一化处理,得到了关于硬岩隧道洞口爆破振动的萨氏经验公式;为爆破开挖设计优化提供了参考价值。在爆破振动速度研究中,爆破振动速度的最大水平径向分量大于最大水平切向分量,最大水平切向分量又大于最大垂直分量,与软岩隧道得到的规律是相反的。达到洞口位置时,爆破振动速度呈现出明显的增加,坡表表面呈现出明显的振动放大效应,这与在软岩隧道中得到的规律是一致的。  相似文献   

4.
在建筑物附近进行爆破作业产生的爆破振动,会引起结构一定程度的损伤,对结构的安全性和耐久性产生影响。根据现场工程情况,采用有限元软件ANSYS建立砌体结构的计算模型,对爆破地震波作用下其受力和变形进行数值模拟分析。研究表明,爆破地震波作用时,房屋门、窗户的四角部位和墙角等是易产生应力集中和破坏的关键部位;结构对爆破振动的响应程度随着结构物高度的增加而增大;砌体结构设计施工和在砌体结构附近进行爆破作业时,应采取相应减振措施,以降低爆破振动的危害。  相似文献   

5.
针对岩溶地区隧道爆破开挖对溶洞围岩和施工安全的直接影响,对广东清(远)连(州)高速公路白须公隧道救援通道爆破震动进行了监测。通过对溶洞壁的质点振动速度峰值统计分析,总结了爆破地震波在溶洞壁上的衰减规律,得出了隧道爆破对于临近溶洞的安全质点振动速度峰值。监测结果表明:隧道爆破震动中,相邻的溶洞壁径向的振动速度较小,垂直切向和纵向的振速相当;随着比例药量的减小,垂直切向和径向的振速逐渐接近。  相似文献   

6.
针对台山核电厂一期工程取水明渠工程段陆上爆破挖岩对取水闸门的影响,根据实际开挖中的爆破振动监测数据,分析了取水闸门爆破振动特性,指出就所测数据而言,在垂直方向爆破振动速度峰值一般具有大于水平径向、水平切向的特点。回归分析了取水闸门地面质点振动速度在水平径向、水平切向和垂直方向的传播衰减规律,提出了为保证建筑物安全而控制不同爆心距下的单段最大段药量,对取水闸门上的实测爆破振动信号进行频谱分析,可知爆破地震波的主振频率主要集中在10~50 Hz,高于取水闸门自振频率5.26 Hz,一般不会产生较大的共振效应。研究对于以后爆破设计、施工有一定的参考意义。  相似文献   

7.
层状岩体中近邻双线隧道爆破的振动响应研究   总被引:1,自引:2,他引:1  
近邻双线隧道爆破开挖时,为了避免新建隧道爆破施工产生的地震波危夏既有隧道的安全和稳定。基于数值模拟和现场试验,分析了层状岩体中采用钻爆法修建近距离双绒隧道的爆破振动响应.结果分析表明,对于既有隧道,迎爆面侧墙处的振动速度和反射拉应力最大,而且振动速度具有很强的方向效应,隧道径向振动速度大于切向振动速度,其规律与现场爆破试验结果有较好的一致性.将爆破对新建隧道本身围岩的振动损伤度和对相邻隧道的振动影响结合起来综合考虑,提出了层状岩体隧道爆破施工中减轻振动的几种措施。并对隧道爆破参数进行了优化.图7,表4,参8.  相似文献   

8.
爆破引起的地面振动是一种复杂地质现象,爆破地震效应对建筑物的影响与多种因素有关.房屋的破坏程度不仅取决于爆破地震的强度,还与房址地形地貌、爆破地震波的频率特性以及房屋结构的固有频率、阻尼比等因素有关.在同样的爆源距下,不同房屋的损伤程度存在一定的差异.  相似文献   

9.
爆破振动频率影响因素分析   总被引:5,自引:1,他引:5  
为了分析影响爆破振动频率的各个因素,为结构物爆破振动安全评价提供可推依据。通过现场爆破振动测试,结合实际分析了频率在爆破振动中的作用,并分析了结构物爆破振动响应的频谱特性,发现爆炸能量、起爆段数、距离以及传播介质对爆破振动频率都有不同程度的影响。通过对爆破振动频率影响因素的分析,指出在爆破振动的测试分析中应充分注意到爆破条件和测试条件的变化。  相似文献   

10.
陶铁军  张光权 《科技信息》2011,(35):162-162
本文主要从以下几个方面对爆破地震效应的进行了研究:爆破地震动的衰减规律研究;爆破地震波信号的分析处理;爆破地震效应控制以及结构物的爆破振动安全强度问题的研究。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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