RCD砼垂直坝轴碾压的探讨

观音阁 RCD 砼浇筑时分仓次采用顺坝轴向碾压,但在1992年施工中也尝试了垂直坝轴碾压。对垂直坝轴碾压与平行坝轴碾压的有利因素和不利因素进行了对比分析、论证。认为垂直坝轴碾压是可行的。

RCD混凝土垂直坝轴碾压的探讨

观音阁 RCD混凝土浇筑采用顺坝轴向碾压，但施工中也尝试了垂直坝轴碾压。本文对垂直坝轴碾压的优缺点进行了对比分析，并就缺点提出了解决办法，结果是认为垂直坝轴碾压是可行的。

大跨度底轴旋转钢坝在高烈度地震区的应用

大跨度底轴旋转钢坝在高烈度地震区应用会遇到不均匀沉降的问题,可能会导致钢坝产生变形甚至失稳,采用弹性地基梁的方法及三维有限元的方法计算分析了大跨度底轴旋转钢坝在高烈度地震区的受力及变形,确定了大跨度底轴旋转钢坝在高烈度地震区应用具有可行性。

仙摘岩闸坝最佳加固改建方案比选

山溪型河流的治理在满足防洪和蓄水要求的同时还要考虑生态和景观效益。以天台县仙摘岩闸坝工程为例,对其被破坏现状进行分析,根据水文、地质以及工程条件进行坝型比选,给出底轴驱动翻板坝这一创新形式,介绍了底轴驱动翻板坝基本结构及原理,并通过科学水力计算得出合理的角度参数,实现壅水、行洪功能,改善了传统闸坝在大跨度、低水位河道控水性不足的弊端。改造后的仙摘岩闸坝结构刚度大,能承受一定的碎石冲撞及激流压力,较好地适应当地的水文特点,控制过水流量的操作便捷且安全,能有效地控制山溪型河流蓄水及泄洪过程。

景观生态闸闸型选择研究

近年来,各种类型的景观生态闸应运而生,常见的闸型有底轴旋转式钢坝、气盾式钢坝和液压翻板坝等。各闸型各有优缺点,不同闸型的工程呈现效果存在较大差异,需根据工程的特点及边界条件仔细甄别适应的闸型。基于此,文章深入分析了三种常见生态闸的闸型特点及使用效果,提出各闸适用性,为各工程水闸的合理选型提供了一定参考。

Triaxial creep tests of weak sandstone from fracture zone of high dam foundation

The lithology of fracture zone which was developed at the dam foundation of a hydropower station is weak sandstone with poor integrity and pore cementation contact.Its creep properties have a significant impact on the deformation and stability of the dam.Based on the characteristics of loose organizational structure,high moisture content and poor mechanical properties,the triaxial compression tests and creep tests were carried out,respectively.The results show significant non-linear,low strength and no obvious strength peaks.Both axial and lateral strains are achieved more than 3%when the tests are failed.The weak sandstone has a significant creep property,but only transient and steady state appear under low stress.Increased stress causes creep intensified and lateral strain gradually exceeds axial strain.In the failure stage,it has characteristics of large axial plastic deformation,obvious volumetric ductility dilation and large steady creep rate.The accelerated creep appears shortly after transient loading under confining of pressures 1.0 MPa and 1.5 MPa.Therefore,an improved Burgers creep model considering the non-linear characteristics of weak sandstone is built based on hyperbolic equation and the creep parameters are identified.This model can well describe the creep properties of weak sandstone.

底轴驱动翻板坝在福州生物医药和机电产业园规划区排涝工程中的应用

城市河道治理在满足防洪排涝功能性需求的同时还需发挥生态和景观效用。该文以福州市生物医药和机电产业园规划区排涝工程为例,分析底轴驱动翻板坝在河道行洪排涝、水环境改善等方面的优势,论述底轴驱动翻板坝工程布置方案及参数设计,通过科学合理调度,实现汛期卧门行洪排涝,非汛期立门挡水形成人工瀑布,营造良好水环境。

Creep failure mode and criterion of Xiangjiaba sandstone

Based on the results of conventional triaxial compression tests and triaxial compression creep tests on Xiangjiaba sandstone,the failure modes in short-term tests and creep tests,fractography of sandstone after creep failure,short-term and creep failure criterion are analyzed.In the short-term tests and creep tests,the sandstone samples fail in a mix mode consisting of shear failure in a single main plane and tensile failure.Confining pressure can restrict brittle failure and enhance the ductility of sandstone.In the creep tests,brittle fracture is reduced and plastic deformation can fully be developed compared to the condition of short-term tests.And the shear fracture surfaces are flat and they are covered by small particles as a result of friction.When confining pressure increases,particle size decreases while the degree of friction on shear plane increases.On the tensile failure plane,the tensile trace and direction of tearing could be clearly observed.There are obvious tearing steps on the tensile failure plane and tearing laminated structure on the front edge of tearing fracture.The same criterion can be used for the short-term and creep behavior,and the fitting effect using the MOGI criterion is better than the DRUCKER PRAGER criterion.The cohesion and friction angle calculated by the MOGI criterion are in good accordance with those calculated by the MOHR COULOMB criterion.

气盾坝技术在提升修竹溪下党乡集镇河段水景观中的应用

受上游浙江省境内水电站发电流量影响,枯水期修竹溪寿宁县下党乡集镇河段水量不稳定,水景观效果差,需要通过在上游建设低水头活动拦河坝调节下泄水量,用以美化集镇区水景观。该文分析比较底轴翻板钢坝、橡胶坝、液压支撑坝和气盾坝等4种低水头活动拦河坝,确定采用气盾坝调节景观流量。经结构分析计算,气盾坝支撑气囊所能承受的最大线拉力、锚固螺栓强度、钢盾板抗弯强度与挠度均满足规范要求,可供类似工程参考。