岩溶发育地区桥梁深基础施工的几个问题

本文阐述了在岩溶发育地区建造桥梁深基础时有关勘察设计、施工及故障处理等技术问题,通过实践总结了经验。 在岩溶地质条件下进行桥梁基础的施工,难度是很大的。尤其是在某些岩溶十分发育的桥梁基础,需要穿透大量的溶沟、溶槽或溶洞而埋置在很深的可靠基岩上时,这种岩溶深基工程的施工将更加困难。 由于岩溶现象是某种可溶性岩层,受到水流常年的侵蚀,逐渐被溶蚀成各种形态的空洞,这些空洞一般都是以十分隐蔽的以各种各样极为复杂的形态出现在深浅不一的地下,它们的实际大小、走向和它们的分布规律都是变化莫测的。以现有国内的勘测手段要很详细而准确地摸清楚还是一件不容易的事情。因此,遇到这种复杂地质条件,要修建各种稳固的铁路桥梁基础,有很多问题需要不断摸索和探讨。 近年来,由于铁路建设事业的不断发展,新修铁路线要通过岩溶地区的可能性越来越大,加上在我国目前的铁路桥涵设计、施工规范里都还没有专门的章节和详细的技术条文对这种特殊基础工程加以说明。所以,岩溶桥梁深基础工程的施工方法和注意事项已引起很多施工单位的广泛注意。 为了及时交流有关这类地质条件下的深基工程的施工经验,现将我公司最近在衡广复线雅瑶大桥施工中遇到的一些实际问题,诸如:岩溶深基在设计时需要注意的问题;

北流县农村金融学会成立

北流县农村金融学会成立大会暨第一届年会于1992年9月18日召开。参加这次大会的有农行玉林地区中心支行、玉林地区农村金融学会、北流县委、县人民政府、县财委、县民政局、县人民银行及兄弟行的领导,北流县支行各股室和营业所、信用社的代表共130多人。

Comparison on construction of strut-and-tie models for reinforced concrete deep beams

With consideration of the differences between concrete and steel,three solutions using genetic evolutionary structural optimization algorithm were presented to automatically develop optimal strut-and-tie model for deep beams.In the finite element analysis of the first method,the concrete and steel rebar are modeled by a plane element and a bar element,respectively.In the second method,the concrete and steel are assigned to two different plane elements,whereas in the third method only one kind of plane element is used with no consideration of the differences of the two materials.A simply supported beam under two point loads was presented as an example to verify the validity of the three proposed methods.The results indicates that all the three methods can generate optimal strut-and-tie models and the third algorithm has powerful capability in searching more optimal results with less computational effort.The effectiveness of the proposed algorithm III has also been demonstrated by other two examples.

Flexural behavior of hybrid fiber reinforced high performance concrete deep beam

In order to reveal the flexural behavior of hybrid fiber reinforced high-performance concrete deep beam, 16 high-performance concrete deep beams of different fiber volume content have been tested according to the state standards and testing methods. The effects of hybrid fiber on the yield moment and bending bearing capacity of the cross-section have been analyzed, the calculation method for the bending capacity＇ is discussed and the propositional formula are provided as well. Results shoxv that the flexural properties increased obviously when add ≤1.0% of volume content steel fibers and ≤0.11% of volume content polypropylene fibers in to deep beam. The results are useful to the further amendments of fiber reinforced concrete structure technical regulation （CECS 38：2004）.

孰是孰非？──一起利用举报侵吞巨款案侦破纪实

孰是孰非？──一起利用举报侵吞巨款案侦破纪实方凤联频频举报１９９３年元旦刚过，广西壮族自治区人民检察院玉林分院就收到一封北流县松花镇松花村治保委员梁深全写的举报信，信中说：“１９９２年１０月中旬，松花村公所拟出售九套商品房，由该村干部梁望雄负责办理售...

Nonlinear vibration of edged cracked FGM beams using differential quadrature method

This paper investigated the nonlinear vibration of functionally graded beams containing an open edge crack based on Timoshenko beam theory.The cracked section is modeled by a massless elastic rotational spring.It is assumed that material properties follow exponential distributions through the beam thickness.The differential quadrature(DQ) method is employed to discretize the nonlinear governing equations which are then solved by a direct iterative method to obtain the nonlinear vibration frequencies of beams with different boundary conditions.The effects of the material gradient,crack depth and boundary conditions on nonlinear free vibration characteristics of the cracked FGM beams are studied in detail.