皖中泥质岩工程性质探讨

历来对半胶结泥质岩风化等级划分都带有许多主观性,从而影响提承载力,有的规范要求可不对半胶结岩石进行风化程度划分,但有时要对这些岩石进行工程地质细分,从而准确确定各分层的承载力与摩阻力。统计了合肥、六安、淮南、安庆地区等大量实践资料,用标准贯入击数、重型圆锥触探实验击数等原位测试手段来划分泥质岩风化等级,并对泥质岩的承载力与摩阻力等工程地质性质做出了评价。     

注水煤体应力能 V-f 转化与释放机理研究

文章分析了在煤层注水湿润后煤体弹性能的转化与消耗过程，给出在湿润状态下能量由体变弹性能向形变弹性能转化进而自耗释放的理论模型。指出在坚硬干燥煤体中，注水后在水压力和毛细力的切割作用下，裂隙大量扩展，丰富了自由裂隙，产生更多的裂隙启发(裂隙切口)，使原来近似的刚性煤体变成由裂隙分割的块体组成的组合体或半组合体。裂隙中水的粘滞作用及水分子吸附力使块体问粘性结合、刚度降低、形变增大。煤体形变弹性能自身消耗释放的形式有3种：产生剪应力导致自由裂隙问错动摩擦；强度降低，使裂隙启发被劈裂成自由裂隙；湿润煤体蠕变性增强，产生整体性移动作功。初步给出能量消耗的量化表达式。通过这一理论，能建立煤层注水湿润度与冲击地压灾害发生的更直接的关系，使进一步量化该关系成为可能。从更深层次解释煤层注水防治冲击地压的机理。     

中超长钻孔灌注桩的沉降计算

针对现有的桩基沉降计算理论不仅难以完整地描述桩－土系统的复杂程度，在应用上也难以满足各方面的要求，根据中超长钻孔灌注桩的实际情况，采取一些合理的简化措施后，提出了一种实用的桩基沉降计算方法，实例分析表明，该方法可较好地预测桩的沉降量。     

钢筋砼摩擦耗能支撑框架结构的单元刚度和力学模型分析

为研究钢筋砼摩擦耗能支撑框架结构的动力反应性能 ,对其中的摩擦耗能器单元和框架杆单元的单元刚度和力学模型做了分析。钢筋砼摩擦耗能支撑单元由支撑杆单元和钢板—橡胶摩擦耗能器单元组成 ,支撑单元可取空间杆单元 ,摩擦耗能器单元为平面应力矩形单元。摩擦耗能器单元的剪切恢复力曲线为理想的弹塑性曲线 ,根据耗能器单元的力学模型 ,可确定其在每一时刻的刚度 ;框架结构空间杆单元的恢复力模型采用双线型模型 ,根据杆单元的力学模型 ,可确定其在每一时刻的刚度。并利用所编制的程序对十层单榀两跨空间普通框架和摩擦耗能支撑框架在地震作用下进行了弹塑性反应时程分析 ,结果表明耗能支撑框架的顶层最大位移明显小于普通框架     

辽阳化纤公司198#住宅楼短螺旋钻孔灌注桩施工及效益分析

介绍了辽化198#住宅楼短螺旋钻孔灌注桩施工方法，认为该工艺具有二效快、质量好、节约材料、降低二程成本，在适当条件下，采用这种方法可收到好的效益。     

填土引发的桩基负摩阻力问题及其灌浆处理技术

阐述了填土地基的沉降计算方法，分析了填土引发桩基负摩阻力的机理及危害，探讨了采用压力灌浆技术加固填土地基、消除桩基负摩阻力、控制桩基沉降的加固机理、施工工艺和应用效果。     

Interaction between two sliders in a system with rate- and state-dependent friction

This study examines slip recurrence patterns in a two-block spring-slider model with rate- and state-dependent friction. Both weak and strong heterogeneities are considered with different settings of coupling stiffness. The results show that the recurrence pattern of slips strongly depends on the degree of coupling between the two blocks. With strong coupling between the two blocks (e.g., kc/ki max >~1), the slip pattern of the system is simple and characterized by periodical stick-slips, with the two blocks slipping together. With strong heterogeneity in friction strength, period-2 motion is found for moderate coupling stiffness (kc/ki max=0.4) between the two blocks. More complicated patterns are found with weak coupling stiffness (kc/ki max=0.2) and strong heterogeneity. With strong heterogeneity, very weak coupling leads to chaotic slip patterns. With coupling stiffness kc=5 ki max and strong heterogeneity, chaotic slip patterns are not found, in contrast with the results by Huang and Turcotte who employed the classical static/kinetic friction law.     

Comparative study of the inelastic response of base isolated buildings

This article presents a numeric comparative study of the inelastic structural response of base isolated buildings. The comparative study includes the following isolation systems: laminated rubber bearings, New Zealand one, pure friction and the frictional pendulum ones. The study is based on obtaining non‐linear response spectra for various design parameters using six earthquake records. Usually the base isolation of a new building seeks to maintain the structure in the linear elastic range. The response of old weak buildings or the response of new ones subjected to extreme earthquakes may not be, necessarily, in the aforementioned ideal elastic range. Consequently, it is important to characterize the response of isolated buildings responding inelastically. A conclusion from this research is that the isolators affect significantly the structural response of weak systems. Rubber isolators seem slightly less sensitive to plastification that may occur in the structure compared to friction isolators. Ductility demands in the structure are affected significantly by friction and neoprene protected systems, in particular sliding ones where larger demands are obtained. Copyright © 2002 John Wiley & Sons, Ltd.     

横山水库除险加固工程的安全论证——土工膜与结构面摩擦试验

土工膜是工程防渗处理的一种主要材料[1]。斜坡面上土工膜与结构面的抗滑稳定直接影响到工程的安全运行。摩擦试验模拟了现场施工和运行情况,得到土工膜与结构面的抗滑剪力和摩擦系数,对工程的安全进行了论证。     

岩溶地区桩基的有限元分析

岩溶地区长桩存在着遇洞率的问题。为了研究岩溶地区桩的受力特点,采用有限元法模拟岩溶地区桩基的工作方式,分析了岩层厚度对桩的影响以及桩的受力状态,并研究了去桩的可能性。计算结果表明:岩层厚度对桩的影响较大,岩层的位置对桩的应力不产生影响,仅对桩的位移产生影响。