摘要：为了定量预测粗糙裂缝内支撑剂覆盖率,开展不同工况下粗糙裂缝内支撑剂覆盖率的试验研究。基于自主设计的粗糙裂缝试验装置,通过控制变量方法进行不同壁面粗糙度、泵注排量、支撑剂质量分数、压裂液黏度等条件下的输砂试验,定性揭示不同施工参数对支撑剂在粗糙裂缝中输送的影响规律,并基于试验结果提出粗糙裂缝内支撑剂覆盖率计算模型。结果表明:以分形维数(变差函数)为主的裂缝壁面粗糙度定量描述方法能够解释支撑剂在粗糙裂缝内运移沉降过程;支撑剂在粗糙裂缝内的运移、沉降和充填行为与光滑裂缝内有较大差异;不同的裂缝壁面粗糙度能导致支撑剂运移、沉降和充填方式的差异;粗糙裂缝输砂需要足够高的压裂液黏度及泵注排量才能保证支撑剂的有效流动;支撑剂质量分数越大需要与之匹配的流体黏度、携砂液排量越大;基于试验结果建立的粗糙裂缝内支撑剂相对覆盖率预测模型,能够实现对不同粗糙裂缝内不同施工参数组合下支撑剂覆盖范围的预测。

摘要：This paper proposes the cooling system type and cooling equipment type which are deep mine with high temperature during the construction,and presents auxiliary cooling measures making up duct temperature rise since compression and heat transfer temperature rise. The cooling system designed against Zhaolou mine's ground temperature and weather conditions,with its sprinkler room handling an average temperature difference up to 19.5～23.8 ℃,and the average enthalpy difference could reach 48.4～60.7 kJ/kg. At the same time,it gets a series of basic data used for mine construction during the cooling system design and equipment selection according to the measured results; using the analysis software Matlab,it obtains the change relations between the temperature of sprinkler room and fan export supply air temperature,wind casing temperature rise and fan export supply air temperature,working face temperature and supply air temperature,used for the mine cooling which has the similar conditions.

摘要：Segregation results in worse mechanical and durability performance of ***,an accurate modelling of segregation is required for reliable mesoscale *** this context,this paper presents a method to develop the geometric mesoscale modelling of concrete taking into account *** this method,coarse aggregate particles are generated as ellipsoids of random geometry and are randomly placed within *** specimen is stratified in different numbers of layers(NoL)that represent different segregation *** geometric models of four concrete mix designs are generated and the relevant key parameters,*** distribution are analysed and *** addition,the segregation level of generated models is classified based on the volumetric index and the correspondence between segregation level and the value of NoL is *** results show that 1)The generated geometric models with NoL ranging from 1 to 10 align well with real segregation in concrete and can accurately represent the majority of segregation cases resulting from various experimental factors;2)The NoL reflects the segregation level:more layers indicate a more heterogeneous mesostructure;3)The larger aggregates of the generated models tend to settle at the bottom,while smaller aggregates rise toward the top,leading to uneven vertical distribution,especially as the NoL increases;4)the mix 1 with low aggregate content can represent the construction material with large segregation,while the mix 2 is inverse.

摘要：矿山用工程机械轮胎价格十分昂贵、使用周期短、更换新胎成本很高,因此需要对其进行定期维护.刺扎、污染、磨耗和速度波动较大等恶劣的工作环境,致使工程机械轮胎使用寿命缩短.对于自卸车载重轮胎来说,使用时易发生胎面脱层、胎侧刺扎、冲击破裂和胎圈损坏等问题.为了满足矿山运输要求,必须改善轮胎胎面胶配方,从而提高胎面耐磨性能.

摘要：针对矿石破碎模型与实际矿石性质差异造成的破碎仿真不准确及磨矿工艺参数难以确定的问题,采用离散元法建立矿石颗粒黏结模型,重点研究基础颗粒的数量组合对颗粒黏结模型精度的影响。依据落重试验破碎的63~53 mm粒级矿石,构建了5组不同粒径颗粒的数量组合及对应的颗粒黏结模型。通过对颗粒黏结模型的破碎仿真及实际矿石的破碎试验,得到破碎后粒度分布结果,对比分析了仿真与试验的破碎后粒度分布差异。研究结果表明:当大颗粒体积不超过总体积的50%,且中间颗粒与大颗粒体积比为0.21~0.22时,破碎仿真粒度的分布与实际矿石破碎试验结果较为一致。在模型体积填充率不变的情况下,不同基础颗粒的数量组合对破碎后颗粒团簇粒度有较大影响,选择合适的基础颗粒数量组合能够提高颗粒黏结模型的精度。

摘要：为提高洞庭湖的防洪能力及增强其枯水期供水能力,提出了适用于洞庭湖区的新型防洪减灾措施——"河湖分离"方案。通过采用数值模拟方法,以洞庭湖1996年型洪水为例,探讨了"河湖分离"方案对洞庭湖区防洪效果的影响,并统计分析了在应用该方案后洞庭湖1996-2014年的蓄水能力。结果表明:洞庭湖实施"河湖分离方案"后,若遇1996年型洪水,湖内有效防洪库容可由1996年的20.91×108m3增加至119.01×108m3,从而增强了洞庭湖的削峰能力。通过统计分析发现,洞庭湖具有很大的蓄水潜力,即使在年极端干旱年份(比如2006及2011年),"河湖分离"方案仍能使得洞庭湖的可用蓄水量超过18.0×108m3,这说明"河湖分离"方案能有效地缓解洞庭湖区季节性缺水的状况。

摘要：With the expansion of a city,the urban green space is occupied and the urban heat island effect is *** the roof surfaces of urban buildings is an effective way to increase the area of urban green space and improve the urban ecological *** provide effective data support for urban green space planning,this paper used high-resolution images to(1)obtain accurate building spots on the map of the study area through deep learning assisted manual correction;and(2)establish an evaluation index system of roof greening including the characteristics of the roof itself,the natural environment and the human society *** weight values of attributes not related to the roof itself were calculated by Analytic Hierarchy Process(AHP).The suitable green roof locations were evaluated by spatial join,weighted superposition and other spatial analysis *** the areas within the Chengdu city’s third ring road as the study area,the results show that an accurate building pattern obtained by deep learning greatly improves the efficiency of the *** roof surfaces unsuitable for greening can be effectively classified by the method of feature extraction,with an accuracy of 86.58%.The roofs suitable for greening account for 48.08%,among which,the high-suitability roofs,medium-suitability roofs and low-suitability roofs represent 45.32%,38.95%and 15.73%.The high-suitability green buildings are mainly distributed in the first ring district and the western area outside the first ring district in *** paper is useful for solving the current problem of the more saturated high-density urban area and allowing the expansion of the urban ecological environment.

摘要：为获得核废料储罐与周围环境界面的温湿度信息,以便模拟不同地质处置时期储罐表面的腐蚀环境,通过对一些典型核能利用国家在高放核废料安全处置研究中对储罐表面温度的长期演变计算进行调研,结合不同埋藏模式推测出适于我国的核废料储罐表面温度演变规律。同时根据国内外对核废料储库中缓冲/回填材料饱和度的变化情况推测我国核废料储罐表面环境中膨润土含水量的时间演变趋势。研究表明,储罐表面初始时温度快速升高,至温度峰值后逐渐下降,为安全起见,最高温应设计低于100℃。膨润土的饱和度受到核废料衰变释热及地下水入渗的双重影响,早期以核废料衰变主导,后来受地下水入渗影响显著。一般认为储罐表面膨润土在3年左右含水量明显增加,约10年左右达到饱和。温湿度长期演变预测将为我国核废料储罐表面腐蚀演变研究奠定基础。