Air-Decking Technique in Bench Blasting

The mechanism and the design parameters of blasting with air-decking are studied. The theory of detonation waves is used to investigate the processes of the one-dimensional plane detonation wave within a borehole. The interac- tion of the rarefaction wave with an interface and reflection on a rigid wall is also analyzed. The same courses of the shock wave are also investigated. This decides the distribution of the pressure of the explosion products changing with time along the borehole. Based on the above theoretical analysis, two conditions should be met for a reasonable range of values of the air-decking ratio in blasting rock. First, the rarefaction wave from the contact interface between detonation products and air reaches the bottom earlier than that of the reflected shock wave from the end of the stemming. Second, the reflected shock wave reaches the contact interface between the detonation products and air earlier than that of the reflected rarefaction wave from the bottom of the borehole. Finally, the reasonable value of the air-decking ratio must be decided theoretically in air-decking blasting. For different explosives, the reasonable range of air-decking ratio varies from 0.15 to 0.4. This result is well consistent with what was obtained by previous researchers.

New technique for identifying varieties resistance to rice blast

After 8 yrs lab experiments and field tests, an advanced technique for identifying varieties resistance to rice blast was developed by a research group in Plant Protection Institute, Zhejiang Academy of Agricultural Sciences. With this technique, the inoculum was prepared on a maize-rice-straw-agar media which was suitable for sporulation of most rice blast pathogen isolates. To avoid possible virulence variation during the vegetative growth, the conidia were harvested and preserved for later different sets of resistance evaluation tests. A simple and precise new method—smear inoculation was used for infection. The experi-

Numerical and Experimental Investigation into Plane Charge Explosion Technique

Plane charge explosion technique (PCET) is one of the major techniques frequently used in large-scale blast-resistant structure tests. An FEM model was established, which can simulate the process of air releasing from the blast cavity. The effects of the charge density, the interval of the charge strip, the distance of the charges from the structure, and the mass of backfill soil on the overpressures applied on the tested structures were analyzed by the FEM model. The quantitative relationships between the peak value and the duration of the overpressure and the above-mentioned affecting parameters were established. Agreement between numerical results and the test data was obtained.

Enhancing rock fragmentation prediction in mining operations:A hybrid GWO-RF model with SHAP interpretability

In the mining industry,precise forecasting of rock fragmentation is critical for optimising blasting processes.In this study,we address the challenge of enhancing rock fragmentation assessment by developing a novel hybrid predictive model named GWO-RF.This model combines the grey wolf optimization(GWO)algorithm with the random forest(RF)technique to predict the D_(80)value,a critical parameter in evaluating rock fragmentation quality.The study is conducted using a dataset from Sarcheshmeh Copper Mine,employing six different swarm sizes for the GWO-RF hybrid model construction.The GWO-RF model’s hyperparameters are systematically optimized within established bounds,and its performance is rigorously evaluated using multiple evaluation metrics.The results show that the GWO-RF hybrid model has higher predictive skills,exceeding traditional models in terms of accuracy.Furthermore,the interpretability of the GWO-RF model is enhanced through the utilization of SHapley Additive exPlanations(SHAP)values.The insights gained from this research contribute to optimizing blasting operations and rock fragmentation outcomes in the mining industry.

复杂地质条件下隧洞无爆破掘进技术研究

针对特殊、复杂不良地质条件下小断面隧洞掘进问题,以张掖市甘州区酥油口下库工程引水隧洞为例,对隧洞无爆破掘进技术展开研究。根据工程地质条件确定支护措施,在Ⅲ、Ⅳ、V类围岩变化不确定状态下,采用悬臂式掘进机作为施工坚硬岩层的无爆破破岩方法。研究结果表明,对于Ⅲ、Ⅳ、V类围岩,悬臂式掘进机利用率随着围岩类别降低,净掘进速度明显提高;对V类砂卵砾石围岩,悬臂式掘进机单循环掘进及一衬速率达到约7.0 m/d;施工效果较好。

水压爆破技术在水工隧洞施工中的应用

针对水工隧洞中常规爆破施工技术中存在的效率低、成本高等施工问题,开展水工隧洞中采用水压爆破技术的研究与评价具有重要的工程意义。依托秦岭输水隧洞工程,通过现场爆破实际监测数据分析评价了水工隧洞中的水压爆破施工工艺、炸药使用量、粉尘浓度、留孔痕迹以及爆破效果。研究表明,水压爆破在水工隧洞开挖中具有广泛应用的巨大潜力,其较常规爆破的炮眼利用率提高了13.3%,爆破后粉尘浓度降低了47.2%。

岩质边坡地质灾害治理中爆破技术的应用分析

岩质边坡地质灾害治理中爆破技术应用广泛,爆破技术能够快速、高效地瓦解岩石,加速地质灾害治理进程。相比传统的人工采石或机械拆除,爆破技术可以大幅节省时间和人力成本。通过合理的爆破设计和参数控制,可以实现对岩石的精确瓦解和控制破碎范围,减少对周围环境的影响,降低治理风险。基于此,文章在对边坡地质灾害治理及爆破技术进行概述的基础上,对岩质边坡地质灾害治理中爆破技术的应用进行研究,提出岩质边坡地质灾害治理中爆破施工的控制建议。

Mitigation of blast loadings on structures by an anti-blast plastic water wall

Seven in-situ tests were carried out in far field to study the blast mitigation effect of a kind of water filled plastic wall. Test results show that the mitigation effect of water filled plastic wall is remarkable. The maximum reduction of peak reflected overpressure reaches up to 94.53%, as well as 36.3% of the minimum peak reflected overpressure reduction in the scaled distance ranging from 1.71 m/kg1/3 to 3.42 m/kg1/3. Parametric studies were also carried out. The effects of the scaled gauge height, water/charge scaled distance(the distance between the explosive charge and the water wall), water wall scaled height and water/structure scaled distance(the distance between the water wall and the structure) were systematically investigated and compared with the usual rigid anti-blast wall. It is concluded that these parameters affect the mitigation effects of plastic water wall on blast loadings significantly, which is basically consistent to the trend of usual rigid anti-blast wall. Some formulae are also derived based on the numerical and test results, providing a simple but reliable prediction model to evaluate the peak overpressure of mitigated blast loadings on the structures.

高炉料面成像工业内窥镜的视场覆盖增强方法

高炉料面形状信息对调节布料操作具有重要参考作用.针对目前工业内窥镜对高炉料面成像视场覆盖范围较小的问题,提出了一种新的视场覆盖增强方法.首先,基于坐标系变换建立工业内窥镜的感知模型,定量刻画工业内窥镜参数与感知区域面积之间的关系;然后,在感知模型的基础上提出料面成像区域面积的计算方法,并提出基于粒子群优化算法优化感知方向的视场覆盖增强策略,实现最大面积的料面区域感知.最后,的实验和应用结果表明,提出的方法可有效提高视场覆盖的料面面积,具有很好的应用价值.

考虑损伤累积效应的矿山边坡稳定性分析及加固方案研究

矿山开采过程中,爆破作为一种极其常用的手段,对周围岩体产生了不可逆转的损伤,一旦超过岩体的损伤极限,将会造成边坡失稳,导致严重的安全生产事故。通过声波测试技术,以声波波速为介质定义了损伤变量,用于描述岩石的损伤程度,对矿山爆破损伤累积效应进行了现场测试,基于现场实测结果建立了考虑累积效应的损伤模型。将该模型进行二次开发,导入FLAC数值模拟软件,对持续爆破条件下矿山边坡的稳定性进行了分析,并提出了加固方案。研究表明:(1)随着岩体经历爆破次数增加,内部损伤程度逐渐增加,最终以突变激增的形式达到完全破坏;(2)通过拟合试验过程中损伤变量与爆破次数、爆破装药量的关系,认为损伤变量的增长与爆破次数的指数关系成正比,同时与爆破装药量的0.5次方成正比;(3)对频繁爆破条件下的边坡稳定性控制方法进行了分析,所提加固方案有助于控制损伤累积导致的边坡失稳。

优质抗病粳稻新品种扬香玉200的选育与应用

扬香玉200是江苏里下河地区农业科学研究所与江苏焦点富硒农业有限公司合作育成的稻瘟病抗性与优质高产协同提升的迟熟中粳稻新品种。该品种于2023年通过江苏省农作物品种审定委员会审定,具有稻米品质优、综合抗性好、高产广适等优点。介绍了该品种的选育过程、特征特性以及主要栽培技术。

三系杂交稻新组合瑜香优191的选育

瑜香优191是湖南湘穗农业科技开发有限公司用自选母本瑜香178A与自选恢复系R19–1配组而成的三系杂交晚籼早熟新组合,该品种株叶形态好、产量高、熟期适宜、抗稻瘟病、香型、米质优、适应广,2022年7月通过国家农作物品种审定委员会审定(国审稻20220236)。介绍了该品种的选育过程、特征特性、栽培技术和制种技术要点,以期为该品种的推广提供参考。

城区基坑开挖爆破振动预测及控制研究

为研究复杂环境下城区基坑开挖爆破振动预测及控制措施,依托现场爆破试验分析了质点峰值振速与主振频率的响应规律,基于以上两个因素提出了爆破振动预测方法。探讨了逐孔起爆与减振沟的降振效果,获得了减振沟的最佳降振范围,制定了爆破振动的控制措施。结果表明:在爆破振动预测方面,通过考虑实际最大单孔药量、实际总药量提出的质点峰值振速及主振频率预测公式实现了对爆破振动的综合预测,其预测值较仅以最大单孔药量的预测值更小,预测精度提高了3.2%。在爆破振动控制方面,现场实施的逐孔起爆与减振沟降振措施效果良好,爆破振动表现为低振速、高频率、短持时的特点。其中,减振沟的降振效果显著,综合考虑质点峰值振速、信号频带能量分布及瞬时输入能量的响应规律,在减振沟背爆侧1~6 m作用半径内降振效果最佳,1 m作用半径内的降振比率最高可达77.5%。对于类似工程,可借鉴爆破振动预测公式进行预先评估,当建筑物距离爆区≤10 m时,建议参考减振沟开挖规模实施降振措施。

煤矿岩巷掘进爆破封孔材料研究

为解决煤矿岩巷掘进爆破施工作业中封孔工艺复杂、易冲孔以及掘进效率低等问题,设计了一种新型流体封孔材料与高效的封孔工艺。该封孔材料是由大理石粉、水与瓜尔胶三者按照70300.15的质量比配制成的混合浆体,使用搅拌与泵送一体机,实现流体耦合封孔,并在顾北煤矿巷道掘进施工中得到应用。实验结果表明,该封孔材料具有黏度高、体系稳定和剪切变稀的流体特性,配合一体机使用,封孔工作效率提高304%,单循环进尺提高14.6%。封孔材料性能优良,封孔工艺简单,掘进效率与爆破效果得到明显提高。

深中通道桥梁工程钢箱梁智能涂装技术

深中通道桥梁工程钢箱梁制造总计约28万吨,钢箱梁制造节段数量多、涂装工作量大。为实现钢箱梁涂装提质增效,钢箱梁外表面和钢桥面采用自动化、智能化涂装生产线进行涂装,包括喷砂除锈、热喷锌铝、喷漆三部分。智能喷砂除锈设备采用喷砂机器人,由外部天车式喷砂机器人系统和地面轨道式喷砂机器人系统组成。智能喷锌铝设备采用热喷锌铝机器人,由2套喷涂小车组成,小车上搭载电弧喷涂电源、电弧喷枪系统和ABB机器人系统等。智能喷漆设备采用喷漆机器人,由2套轨道型多功能伸缩臂机器人系统组成。按照钢箱梁涂装工艺流程,分别采用喷砂机器人、热喷锌铝机器人和喷漆机器人进行相应的喷砂除锈、热喷锌铝和喷漆作业。通过涂装质量验收,喷砂机器人喷砂效率约为人工的4倍以上,一次合格率高;热喷锌铝机器人热喷锌铝效率约为人工的6倍,涂装膜厚均匀;喷漆机器人喷漆效率比人工略高,涂装膜厚均匀。智能化涂装技术提升了钢箱梁涂装质量,质量合格率为100%。

邻近既有线浅埋偏压隧道控爆开挖施工技术

随着日益增长的国家交通基础设施的建设,新建隧道邻近既有线隧道工程越来越多,有效控制新建工程对既有线隧道结构安全影响成为必须考虑的问题。本文结合某邻近既有线隧道的新建铁路浅埋偏压单线隧道施工实践,从施工防护、控制爆破设计、监控量测等关键技术进行介绍,为今后同类工程建设提供借鉴作用。

优质抗病杂交稻启优2165在南安市种植表现及高产栽培技术

启优2165系福建省农业科学院水稻研究所育成的优质、抗病杂交晚稻品种,2020年通过福建省农作物品种审定委员会审定。2021—2022年启优2165在南安市作晚稻试种,平均产量达8137.2 kg/hm^(2),表现生育期适中、米质优、抗性强等特点。总结了启优2165在南安市作晚稻种植的表现以及高产栽培技术。

高炉煤气和助燃空气“双预热”提高高炉风温的研究

介绍了以放散的高炉煤气在燃烧炉燃烧产生的烟气作热源，同时预热高炉煤气和空气的“双预热”方法，将煤气与空气预热至３００℃，实现１２００℃以上高炉风温。与其它提高风温工艺相比较，“双预热”工艺更适合大多数钢铁企业实现高风温，而且可以减少环境污染，有着良好的推广前景。

山区高等级公路石方爆破施工技术研究

按工程类型、地形和地质条件、爆破方法等因素对山区高等级公路石方工程进行了全面分类．根据现代控制爆破理论，提出了山区高等级公路石方爆破施工的系列关键技术，并运用于八达岭高速公路等工程中，均取得了良好的效果．

含钛高炉渣中钛组分的绿色分离技术

介绍了从含钛高炉渣中回收钛的绿色分离技术.该技术包括三个连续的单元操作过程:(1)促使渣中分散于各矿物相的钛组分选择性转移并富集于设计的矿物相-钙钛矿,实现“选择性富集;”(2)促进熔渣中富集相-钙钛矿的“选择性析出与长大;”(3)改性渣经选矿分离处理,完成“富集相-钙钛矿”的“选择性分离”.该技术特点是清洁,低成本和处理能力大.