Effect Blasting Excavation of Yujiapeng Tunnel on Stability of Nearby Giant Dangerous Rock Masses (DRM)

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节理岩体爆破数值模型及模拟研究

运用多刚体系统动力学及接触冲击理论建立了节理岩体弹塑性动态本构模型。基于DYNA－2D程序原理及其框架,利用所建模型,模拟了节理岩体的爆破过程,量化了节理岩体在爆炸载荷作用下不同时刻的应力场。     

高速公路堑沟石方深孔预裂爆破

论述了长治—邯郸高速公路某堑沟石方的深孔预裂爆破技术，包括爆破参数的计算与选取、爆破安全性验算、爆破效果等。     

岩体等效变形参数研究

岩体变形参数的确定对岩体稳定性模拟至关重要.提出了确定规则裂隙和不规则裂隙岩体等效变形参数的一种模型, 探讨了岩体等效变形参数的规律.通过对不考虑渗流-应力耦合时岩体等效变形性能的研究, 可以发现岩体的等效变形参数不仅与各组结构面的几何形态、结构面变形参数、岩块变形参数等有关, 而且与不同组系结构面间的交切形态有关.岩体的REVs具备以下几点规律: 首先REVs具有多尺度效应和不确定性.其次, REVs与结构面各几何形态要素之间有如下关系: 平均迹长越大, 平均间距越小, 方向角的方差越大, 结构面分布越凌乱, REVs的取值越小.REVs与岩块、结构面变形参数之间有如下关系: 结构面变形参数与岩块变形参数的差异程度对REVs的取值没有明显影响, 但是不同组系结构面或是同一组中的各条结构面, 其变形参数差异越小, REVs的取值将越小.      

钻头破岩振动低频特征室内实验研究

钻头破碎岩石时会产生宽频的振动信号,不同频段的信号蕴含了不同的信息,由于高频段信号能量低、衰减大,不易检测,因此,就钻头破岩信号在低频段特征进行了研究,通过不同岩性岩样的微钻实验数据分析,发现破碎不同岩性的岩石产生的信号在低频段具有固定的频率特征。     

声波测试技术在评价爆破震动对岩体的影响中的应用

在抽水蓄能电站上水库盆的岩体开挖过程中,通常采用工程爆破的技术手段。爆破施工中要尽可能减小爆破震动对上水库盆的影响,控制岩体松动破坏的范围,为下一步防渗工程的实施奠定基础。如何在提高工程施工效率的同时严格控制爆破震动对岩体产生影响,需要通过各种监测手段和技术方法来监测、分析和评价爆破施工对岩体的影响范围,然后来指导爆破施工。本文通过具体工程案例,介绍了施工前或施工后通过声波测试的实际应用,来评价爆破震动对周围岩体的影响,并圈定具体影响范围。     

核电站扩建工程基坑开挖爆破振动安全控制

结合秦山核电二期扩建工程,在已运行核电站附近新扩建核电站的大型基坑开挖过程中进行爆破振动的监测与爆破振动的控制。通过理论分析与监测等多种手段对爆破振动进行有效的控制,确保了正在运行核电站的安全。所总结的减震措施经验对其他核电站的爆破振动控制具有借鉴作用。     

链子崖危岩体的稳定性研究—中科院武汉岩土力学所历年工作概述

本文介绍我所历年来对链子崖危岩体开展的裂缝相对位移监测、力学试验和稳定性评价等研究情况。对链子崖危岩体裂缝相对位移的长期监测提出了测试原理和方法,制定了实施方案,分析了观测结果,给出了相应的结论。简述了危岩区各层岩土介质力学试验的原理、方法和获得的各项力学指标。根据所获得的资料,对链子崖危岩体和猴子岭斜坡体的稳定性作了评价。     

裂隙岩体渗流与应力耦合的试验研究

通过对较大尺寸的裂隙岩体试块进行不同侧压力和加载条件下的渗流试验结果研究，分析了裂隙岩体渗流与应力的耦合机理，得出了不同应力条件下裂隙岩体渗流量与应力成四次方的关系。并且得出并非压应力都引起裂隙岩体的渗流量减小，当裂隙岩体受平行于裂隙面方向的单向压应力时，渗流量随着压应力的增加而增加。     

Comparative Study on Calculation Methods of Blasting Vibration Velocity

Due to the extreme complexities in rock blasting and difficulties in theoretical or numerical analysis, and the enormous consumption of explosives in mining and construction operations, empirical or semi-empirical formulae for blasting vibration velocity (BVV) were obtained from observations and measurements in field blast tests and are still widely used all over the world. This paper investigates the fitting degree and characteristics of several calculation methods for BVV based on 34 sets of data samples from 27 projects belonging to 4 types. The results indicate that both the cube-root scaling formula and the square-root scaling formula have relatively good fitting degree, while the multiple regression analysis can give the best fitting outcome if the sample space satisfies certain requirements. Whether the cube-root scaling formula or the square-root scaling formula is chosen to analyze the relationship between BVV and scaled distance depends on the average scaled distance under cubic-root scaling. If the average scaled distance is over 0.1, the cube-root scaling formula should be used; otherwise, the square-root scaling formula should be used. Bigger samples integrated from data samples of different projects but in the same type were then analyzed to get the empirical relations for different types of projects. The correlation coefficients of these relations are quite good, thus these relations can be used for reference in other similar projects. This paper then discusses the physical meanings of parameters in different formulae, sample selection and parameter choice for BVV. It suggests that the current calculation methods for explosive charge, blasting-to-monitoring distance and scaled distance need to be improved. It also concludes that the integrated BVV from velocity components in three-dimensions is more reasonable on a theoretical basis. It can yield good results in predicting the blasting vibration, and should be used as widely as possible.     

A Survey of Blasting Vibration Regulations

In 1998, the Blast Vibration and Seismograph Section of the International Society of Explosives Engineers formed a working group to collect and compile a list of regulations limiting ground vibrations from blasting. The goal was to locate those countries, states, provinces, and cities that have such regulations, identify which governmental body enforces them, and determine what limits on ground vibrations are imposed upon the blasting operations, and if possible, determine the basis for such regulations. In the course of this study, data was collected from over 60 jurisdictions where peak particle velocity restrictions range from non-existent to very stringent. Some of the regulations were found to be based upon standards grounded in good science, while others possess little or no technical justification. This paper will summarize the findings of the subcommittee, focusing primarily on what the limits are, which type of blasting operations must adhere to them, and to what structures they apply. The degree to which these regulations are based upon valid scientific and engineering research will be discussed. A listing of specific locations having such regulations and information about those regulations will be provided.     

岩体结构对岩石爆破效果的影响

分析了爆破冲击波的传播特点，指出了对岩石破坏最大的是拉伸应力波，并对岩体结构对岩石爆破效果的影响进行了探讨。     

水下岩石爆破参数优化的研究

分析了水下岩石工程爆破技术的发展现状，通过对各方面影响因素的研究分析，认为影响水下岩石爆破炸药单耗的主要因素是岩石的RQD，水深H及岩性因素f，推导出了水下岩石爆破炸药单耗q的公式。     

A Numerical Study on Wave Transmission Across Multiple Intersecting Joint Sets in Rock Masses with UDEC

This paper presents a numerical study on wave transmission across jointed rock masses with UDEC, where multiple intersecting joint sets exist. The capability of UDEC of studying wave transmission across rock joints is validated through comparison with analytical solutions and experimental data. Through parametric studies on wave transmission across jointed rock masses, it is found that joint mechanical and spatial parameters including joint normal and shear stiffnesses, nondimensional joint spacing, joint spacing ratio, joint intersecting angle, incident angle, and number of joint sets together determine the wave transmission. And for P wave incidence, compared with other parameters, joint normal stiffness, nondimensional joint spacing, and joint intersecting angle have more significant effects on wave transmission. The physical reasons lying behind those phenomena are explained in detail. Engineering applications and indications of the modeling results are also mentioned.     

Estimating the Strength of Jointed Rock Masses

Determination of the strength of jointed rock masses is an important and challenging task in rock mechanics and rock engineering. In this article, the existing empirical methods for estimating the unconfined compressive strength of jointed rock masses are reviewed and evaluated, including the jointing index methods, the joint factor methods, and the methods based on rock mass classification. The review shows that different empirical methods may produce very different estimates. Since in many cases, rock quality designation (RQD) is the only information available for describing rock discontinuities, a new empirical relation is developed for estimating rock mass strength based on RQD. The newly developed empirical relation is applied to estimate the unconfined compressive strength of rock masses at six sites and the results are compared with those from the empirical methods based on rock mass classification. The estimated unconfined compressive strength values from the new empirical relation are essentially in the middle of the estimated values from the different empirical methods based on rock mass classification. Similar to the existing empirical methods, the newly developed relation is only approximate and should be used, with care, only for a first estimate of the unconfined compressive strength of rock masses. Recommendations are provided on how to apply the newly developed relation in combination with the existing empirical methods for estimating rock mass strength in practice.     

Study on the Safety of the Foundation Rock Masses in the Tangkou Bank of the Taipinghu Bridge

The Taipinghu Bridge is an important project, and the safety of rock masses of its foundation is very crucial. This article analyzes the potential causes of the deformation of the rock masses of the bridge foundation, and uses the Fast Lagrangian Analysis of Continua to analyze the geologic model. The simulating process shows that no mater in the excavating process or in the loading process the rock masses are suit for the engineering. The modeling and analyzing process can be used for reference.