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1、哈尔滨工业大学工学硕士学位论文 I 摘 要 目前我国机床制造业正在向现代化、大型化方向发展，全国各地经济开发区 内机械加工大型厂房如雨后春笋迅速拔地而起。根据机加工艺的需求，在单层工 业厂房中锻锤机器是必不可少的加工设备。锻造部件工艺中锻锤施加的往复循环 动荷载通过基础传给土层，再以波的形式在土中扩展，使得相邻锻锤基础的排架 柱基础下的持力层不仅承受上部结构的静荷载，而且动荷产生的附加动强度引起 附加沉降变形。本文结合某单层工业厂房墙体、排架柱开裂、吊车梁倾斜、加工 部件不能吊装到位，锻造工艺停止生产的具体工程事故提出增加地基刚度的方法， 通过有限元计算、加固设计、施工实施彻底改变工厂停工状况
2、，课题研究具有重 要的实际实用价值。解决了具体实际工程问题。 本文首先针对单层工业厂房排架柱基础加固设计查阅了大量国内、外相关资 料，归纳分析发生墙体开裂的主要影响因素。收集某墙体，排架柱开裂的单层工 业厂房的相关原始设计图纸，近期沉降观测资料，场地工程地质报告。进行实地 查勘，进行排架柱基础、5T 锻锤基础土层的加速度实测工作，得到了产生事故的 根本原因是动力机器基础加速度超过规范的允许值。对症提出了增强地基刚度的 方法，达到降低基础的沉降变形与加速度值的目的。 地基刚度是土层单位受力与其线位移之比，在排架柱荷载和动力往复循环荷 载传给基础顶部数值固定条件下，减小线位移的唯一方法是提高地基刚
3、度。针对 排架柱基础土层加固需在厂房内进行的实际情况，结合工程地质条件，提出采用 高压旋喷桩与原基础持力层共同工作组成复合地基提高地基刚度的技术思路。为 此利用有限元软件 PKPM 开展排架柱底部内力计算，沉降变形计算。设计高压旋 喷桩的桩径、桩长、平面布置，完成满足静、动荷载共同工作时土层承受荷载能 力的复合地基承载力设计值计算，和高压旋喷桩与柱独立基础可靠连接节点设计， 对加固前后的持力土层刚度进行对比评价。根据高压旋喷桩静载荷试验与现场原 位开挖实际量测，验证了计算结果的可靠性，桩径的实际保证程度，验证加固工 程设计的合理性与先进性。 最后根据治病要治本的要求，必须降低动力机器基础的往复
4、冲击荷载在土层 中产生的加速度值。根据牛顿第二定律，在惯性力的作用下，降低加速度的唯一 办法是增加动力基础质量和提高土层抗压刚度。本文针对 5T锻锤基础加速度与幅 值均超出规范允许值的实际情况，提出高压注浆灌注桩与大块动力基础组成组合 型基础的技术思路。为此本文结合基础的设计计算，创新提出了高压注浆灌注桩 基础与大块基础共同工作的技术措施，对比了加固前后持力土层抗压刚度，有力 地证明了降低基础沉降变形的新思路-增强地基刚度的方法是正确、合理、可靠的。 哈尔滨工业大学工学硕士学位论文 II 关键词：动力机器基础；加速度；地基刚度；复合地基设计；组合基础设计 Abstract Currently,
5、 machine tool manufacturing industry of our country is developing with more modernization and lager-scale, and a great deal of large-scale manufacturing factory buildings arise in economic development zones throughout our country. According to the requirement of machining process, forging hammer mac
6、hine is the one kind of the essential processing equipments for single-storey industrial buildings. The cyclic load caused by forging hammer is transferred through foundation to soil in the process of forging machine parts, then spreading in the form of waves, so the bearing stratum under bent frame
7、 column foundation of adjacent forging foundation not only supports the static load of upper structure, also settles with additional dynamic stress caused by dynamic load. Based on engineering accidents of single-storey industrial buildings, for instance, crack of wall and bent frame column, tilt of
8、 crane beam, and forge parts can not be lifted to right place, and whats worse, forging production has to stop work; thus, in order to resolve all these engineering problems, the method to strengthen foundation stiffness is proposed in the paper to thoroughly and completely solve the state of produc
9、tion halting by means of finite element calculation, reinforcement design and construction techniques. The research has important practical value in solving the above engineering problems. Firstly, on account of bent frame column reinforcement design of single-storey industrial building, a large num
10、ber of domestic and foreign related literature and data were obtained to summarize and analyze the most important influencing factors to crack of wall. The original design drawings of some single-storey industrial building with cracking wall and bent frame column were collected, as well as the recen
11、t settlement monitoring data and engineering geological report. By field surgery and measuring acceleration of soil layer of bent frame column foundation and 5t-forging foundation, it can be obtained that the primary cause of the engineering accident is that the acceleration of dynamic machine found
12、ation exceeds the allowed value of the code. The strengthening foundation stiffness method was proposed and the settlement deformation and the acceleration of foundation were successfully reduced. Foundation stiffness is the ratio of the unit force bore by soil to its linear displacement, so the onl
13、y method to increase foundation stiffness is to decrease the linear displacement when the load of foundation top is constant transferred from bent frame column and dynamic machines. On the basis of the soil of bent frame foundation must be reinforced in the industrial building and the engineering ge
14、ological conditions, the technology approach was proposed that high-pressure rotary jet grouting pile and the original foundation bearing stratum will be applied to increase the foundation 哈尔滨工业大学工学硕士学位论文 III stiffness as one kind of composite foundation. Therefore, the finite element software PKPM
15、was used to calculate the internal force of the bottom of bent frame column and the settlement displacement. The length, diameter and layout of high-pressure rotary jet grouting pile were designed to make the composite foundation provide enough bearing capacity with static and dynamic loads, and the
16、 reliable joints between high-pressure rotary jet grouting pile and independent column foundation were also designed, and the stiffness of foundation bearing stratum before reinforcement will be compared and evaluated to that after reinforcement. According to the results of in-situ static load test and in-situ excavation measurement of high-pressure rotary jet grouting pile, the reliability of calculation and the le
