时序分析在开采沉陷动态参数预计中的应用

应用时间序列分析法,对开采沉陷动态过程的概率积分法预计参数进行分析,建立动态预计模型。用该模型可对参数的未来值进行预计,然后利用预计结果进一步预计地表的移动变形,解决了开采沉陷的动态预计问题。应用此法,地表下沉的相对预计误差一般为４％左右,与传统方法相比,预计精度可提高５％～１５％。     

厚松散层下开采预计的概率积分法修正模型

由于厚松散层下开采具有明显不同于一般地质条件下的沉陷特性,结果导致在用传统的概率积分法对其预计时,预计结果与实际往往偏差较大.基于厚松散层土体与基岩岩性不同,根据岩层移动分层传递的观点,结合厚松散层下开采地表移动特征,建立了厚松散层下开采地表移动预计的概率积分法修正模型,对厚松散层下开采地表移动预计及建筑物保护有一定指导意义.     

神府——东胜煤田地表塌陷预测及防治

根据钻孔资料，运用概率积分法预测了矿区的地表移动程度；并采用灰色模型对典型矿井综合开采面引起的地表最终塌陷值在实测数据的基础上进行了预测。该煤矿开采后，塌陷严重大部分矿井地表最大下沉值和水平位移值均超过有关设计规范允许值。在建筑物和线路及地表水体下开采时，除采取井下预留设保护煤柱和提前施工放水孔等措施外，还要加强井下观测，应用拉杆、圈梁等地面防护措施。塌陷地带用开采废弃土石和矸石充填后，及时种植树     

开采沉陷动态参数预计的三次指数平滑法

在我国,概率积分法是应用最多的一种开采沉陷预计方法．该方法中的预计参数在不同采动程度下是变化的．能否准确获知动态参数的变化规律将决定着开采沉陷的预计精度．为较好地解决这一问题,引入了一种动态参数预计的新方法,即三次指数平滑法．应用此方法对实测资料进行了预计和比较,结果表明,各预计参数的平均相对误差都小于4％．由此可见,该方法对开采沉陷的预测具有一定的应用价值．     

开采沉陷动态参数预计的三次指数平滑法

在我国,概率积分法是应用最多的一种开采沉陷预计方法.该方法中的预计参数在不同采动程度下是变化的.能否准确获知动态参数的变化规律将决定着开采沉陷的预计精度.为较好地解决这一问题,引入了一种动态参数预计的新方法,即三次指数平滑法.应用此方法对实测资料进行了预计和比较,结果表明,各预计参数的平均相对误差都小于4%.由此可见,该方法对开采沉陷的预测具有一定的应用价值.     

巨厚松散层下条带开采地表移动规律分析

巨厚松散层下条带开采引起的地表移动规律及地表移动参数有明显的特点 ,采用概率积分法预计地表移动变形结果的精确与否 ,关键在于地表移动参数 .针对焦作矿区内巨厚松散层的地层条件 ,以条带开采地表移动实测资料为基础 ,用数学方法分析了巨厚松散层下条带开采地表移动规律及地表移动参数 ,并得出地表移动参数与地质采矿条件之间的函数式     

Subsidence control method by inversely-inclined slicing and upward mining for ultra-thick steep seams

Ultra-thick steep coal seam mining will inevitably lead to the increase of greater and violent ground subsidence and deformation. A subsidence control method by inversely-inclined slicing and upward mining is proposed in this paper. By this method, the sequence of collapse of overlying strata and the direction of propagation of strata movement are changed, the extent of roof-side deformation thereby is lessened, and boundary angle of roof-side subsidence is reduced by 5°–10°. The mechanism of this mining method for control of strata movement has been evidenced by numerical simulation and experiments with similarity materials. A subsidence prediction model based on the variation of mining influence propagation angle can be used to evaluate the surface movement and deformation of the mining method. The application of the method in No.3 Mine in Yaojie mining area has yielded the expected result.     

巨厚松散层下条带开采地表沉陷机理及岩层移动模型的探讨

通过研究认为目前的岩层移动模型不能很好地分析巨厚松散层下条带开采岩土层的移动机理,对地表沉陷的主控因素和机理进行了理论分析和模拟试验,探讨了巨厚松散层下条带开采岩土层移动的复合介质模型.     

采动区地基、独立基础与框架结构共同作用的力学模型

根据采动区地表变形的规律和独立基础框架结构受力和变形特点，采用合理的地基模型、基础与上部结构共同作用模型和开采沉陷模型，综合应用结构力学、矿山开采沉陷学、土力学、材料力学等相关理论，建立了采动区地基-独立基础-框架结构共同作用的理论计算模型，该计算模型综合考虑了开采盆地形成过程中地表变形对建筑物的动态影响，从理论上揭示了建筑物位于下沉盆地不同位置时，地表变形与建筑物附加变形和附加内力的关系，并推导出计算采动区建筑物附加变形和附加内力的计算公式，通过计算实例进行了验证，为采动区上方框架结构建筑物的保护、加固和设计提供了理论计算依据．     

Hydraulic support crushed mechanism for the shallow seam mining face under the roadway pillars of room mining goaf

While the fully-mechanized longwall mining technology was employed in a shallow seam under a room mining goaf and overlained by thin bedrock and thick loose sands, the roadway pillars in the abandoned room mining goaf were in a stress-concentrated state, which may cause abnormal roof weighting, violent ground pressure behaviours, even roof fall and hydraulic support crushed(HSC) accidents. In this case,longwall mining safety and efficiency were seriously challenged. Based on the HSC accidents occurred during the longwall mining of 3-1-2 seam, which locates under the intersection zone of roadway pillars in the room mining goaf of 3-1-1 seam, this paper employed ground rock mechanics to analyse the overlying strata structure movement rules and presented the main influence factors and determination methods for the hydraulic support working resistance. The FLAC3 D software was used to simulate the overlying strata stress and plastic zone distribution characteristics. Field observation was implemented to contrastively analyse the hydraulic support working resistance distribution rules under the roadway pillars in strike direction, normal room mining goaf, roadway pillars in dip direction and intersection zone of roadway pillars. The results indicate that the key strata break along with rotations and reactions of the coal pillars deliver a larger concentrated load to the hydraulic support under intersection zone of roadway pillars than other conditions. The ‘‘overburden strata-key strata-roadway pillars-immediate roof" integrated load has exceeded the yield load that leads to HSC accidents. Findings in HSC mechanism provide a reasonable basis for shallow seam mining, and have important significance for the implementation of safe and efficient mining.     

采空区上覆岩层移动破坏动态力学模型的应用

采用采动岩体动态力学模型,对采动引起的覆岩移动破坏的时空规律进行了研究,结合兴隆庄矿５３０６工作面的地质、开采条件,对采动引起的断裂带发育发展规律,岩体内部离层发生发展规律、地表下沉规律等问题进行了分析,并对观测结果作出了较以前的各种理论模型更为符合实际的解释,该模型可在实际工作中得到了很好地应用。     

PTS采动沉陷模型研究

在厚冲积层条件下，采动沉陷盆地中基岩上表面形成的下沉空间可以认为是采空区向上传播的结果，也是地表得以下沉的必要条件。由于冲积层结构松散，抗弯能力低。抗剪强度也小，与基岩相比，属于软弱层，而基岩对整个上覆岩层的移动变形及破坏过程起着控制作用，因此，基岩可认为是地表沉陷的控制层。本文采用不同的思路和方法来建立厚冲积层条件下的采动沉陷模型，并推导出了计算公式最后用实例进行了验证。     

厚松散层放顶煤开采条件下地表移动参数研究

用概率积分法预计地表移动与变形,其准确度关键在于地表移动参数的选取精度.而厚松散层条件下开采地表移动参数,有其明显的自身特点和规律.在鹤壁矿区实测资料的基础上,用数学方法分析了厚松散层放顶煤开采条件下地表移动参数的特点,并得出地表移动参数与地质采矿条件之间的函数关系式,对厚松散层下厚煤层"三下"开采及地表移动预计有一定指导意义.     

矿山采动区砖砌体房屋三维有限元模型的建立与分析

本文针对矿山采动区砖砌体房屋的特点,建立了考虑地基与上部结构协同工作的三维有限元模型。文中给出了墙体、地基及滑动层等单元的破坏模式及处理方法。数值模拟分析及现场试验表明,三维有限元模型能够反映采动区砖砌体房屋的受力状态,理论分析与实测结果基本一致。     

Breaking process and mining stress evolution characteristics of a high-position hard and thick stratum

Based on the boundary support conditions of overlying high-position,hard and thick strata,a Winkler foundation beam mechanical model was built.Computational expressions for the characteristics and position of the bending moment for high-position,hard and thick strata were constructed by theoretical analysis,and the initial breaking position of high-position,hard and thick strata was also analyzed.The breaking process and evolution law of mining stress in high-position,hard and thick strata were studied by similar material simulation tests.Studies show that:due to the foundation deformation effect of the lower strata,the initial break position in high-position,hard thick layers is in the middle of goaf;vertical tension fractures first occur under the middle surface,then tilt tension fractures form at both sides and a non-uniform thickness of the fracture structure forms and produces subsidence deformation;behind the coal wall tilt fractures extend and eventually complete the migration.Mining stress produces obvious changes before and after the breakage of the high,hard and thick stratum;high stress concentration forms in front of the coal wall before breakage and fracture stress concentration significantly reduces after migration.Coal seam mining under high-position,hard thick strata can easily induce dynamic phenomena.     

村庄下双对拉工作面开采的地表和房屋变形

通过北宿煤矿村庄下双对拉工作面开采的地表移动观测,探讨了地表移动变形与房屋变形及其裂缝发育宽度之间的关系,获得了预测房屋裂缝宽度的典型曲线．该曲线可以对房屋裂缝的发育规律作出较为精确的定量预测,对房屋将出现的最大破坏程度有充分的估计．最后,给出了动态下沉系数和水平移动系数的修正公式．     

A roof model and its application in solid backfilling mining

Through changing the axial load on backfilling material compaction test to reflect different overlying strata pressure on backfilling material, the stress-strain relations in the compaction process of backfilling material under the geological condition can be obtained. Based on the characteristic of overlying strata movement in backfill mining, a model of roof thin plate is established. By introducing the stress-strain relation in compaction process into the model and using RIZT method to analyze the bending deformation of roof, the bending deflection and stress distribution can be obtained. The results show that the maximum roof subsidence and maximum tensile stress occurring at the center are 255 mm and5 MPa, respectively. Tensile fracture of roof under the geological condition of Dongping Mine did not occur. The dynamic measurement results of roof in Dongping Mine verify the theoretical result from the aforementioned model, thereby suggesting the roof mechanical model is reliable. The roof thin plate model based on the compaction characteristic of backfilling material in this study is of importance to research on backfill mining theories and application of backfilling material characteristics.     

Fracturing,caving propagation and influence of mining on groundwater above longwall panels——a review of predictive models

Historically there have been a number of different hypotheses and empirical models developed in an attempt to describe the nature of fracturing above longwall panels in underground coal mining. The motivation for such models varies, ranging from understanding the impact of mining on surface subsidence,to back-analysis of caving behaviour in the immediate roof behind the longwall face. One of the most critical motivating factors that is taking on increased importance in many coalfields, is the need for better understanding, and hence prediction of the impact of mining on overlying strata, particularly strata units acting as aquifers for different groundwater horizons. This paper reviews some of the major prediction models in the context of observed behaviour of strata displacement and fracturing above longwall panels in the southern coalfields of New South Wales, south of Sydney. The paper discusses the parameter often referred to as ‘‘height of fracturing" in terms of the critical parameters that influence it, and the relevance and appropriateness of this terminology in the context of overlying sub-surface subsidence and groundwater impact. The paper proposes an alternative terminology for this parameter that better reflects what it is and how it is used. The paper also addresses the potential role of major bedding shear planes mobilised by mining and their potential influence on overlying subsidence and groundwater interference.     

大采深巨厚砾岩综放开采地表沉陷规律

以常村煤矿工程地质资料和地表移动观测站资料为依据,详细分析了2113工作面地表终态下沉、动态下沉和终态水平移动的特征,从机理上研究了大采深巨厚砾岩开采条件下地表形变异常的原因.通过走向方向最大下沉点下沉速度的变化规律和工程实测资料,得出了地表形变与井下冲击地压的关系,确定了地表移动与变形的角量参数.结果表明,受关键层的控制,在整个观测过程中,地表始终处于缓慢下沉状态,且在沉降过程中不存在下沉突变点;下沉速度的反弹可以作为冲击地压危险的预报信息,巨厚砾岩层的运动是发生矿震的主要力源之一.     

Research on Ground Movement Laws for Strip Mining Under Thick Alluvium

With the discrete element method, the simulation and analysis of a series of numerical models were made. This research revealed ground movement laws for strip mining under thick alluvium and gave calculation formulae for the maximum ground subsidence and horizontal movement as a function of basement rock thickness and mining width, thus providing sound evidence for future strip mining under thick alluvium.