裂缝的

The research contents mainly include: First, the influence of foundation constraint condition to the temperature stress is analyzed, the temperature stress formula of ultra-long concrete anchor plate is deduced, then the influence of length to structure crack can be gotten from the formula. Second, a breathing method is set up to solve the problem of temperature stress in ultra-long concrete constructions. By setting the sliding floor, a breathing system is built up and the temperature stress reduced distinctly. Third, the effect of prestress technique in the control of temperature stress is analyzed, it is simulated and calculated through FEA to get the right way to apply the prestress. Forth, the delay of temperature field and unsteady conduction is considered, the temperature field of ultra-long concrete structure with later poured band is simulated, then temperature stress distribution after casting the concrete is calculated, finally the effect of later poured band to temperature stress of ultra-long structure is analyzed.

本文的研究内容主要包括：(1)分析了基础约束对超长混凝土结构温度应力的影响，推导了超长混凝土地基板温度应力公式，从而得出长度对结构裂缝的影响；(2)针对超长混凝土裂缝问题，提出了一种可呼吸的解决方法，通过设置滑动层，使结构成为一种"可呼吸"体系，从而有效的降低温度应力；(3)分析了预应力技术在控制超长结构温度应力中的作用，通过有限元模拟计算，得到合理的预应力施加方式；(4)考虑温度场的滞后效应及不稳定传导，对带后浇带超长混凝土结构浇注后的温度场仿真模拟，计算浇注后的温度应力分布，分析后浇带对超长结构温度应力的影响。

The first batch cracks of concrete bodies in South China had been caused by temperature stresses of cement hydration heat.While the double-action of (1) expansion stress of concrete and (2) temperature stress of day and night's difference of temeperature had been mainly the cause of cracks.

在南方地区，混凝土墙体拆模后的第一批裂缝是由于水泥水化热引起的温度应力造成的，而混凝土收缩引起的收缩应力与昼夜温差引起的温度应力的双重作用，则是导致后续裂缝的主要原因。

On the basis of common theory about the probability-limited state for the structure, the author summarized the cracking law of this penstock and put forward a new definition of particular crack width to judge the structures limited state. This formula is simple and practicable, and it can be used for reference in engineering design.

文章从混凝土裂缝的基本理论出发，采用合理的计算模式，并结合压力管道结构的特殊性，推导出了在内水压力等因素的作用下钢衬钢筋混凝土压力管道最大裂缝宽度的计算公式，并和有限元软件ANSYS分析的结果进行了对比，两者的吻合程度较好。

According to the problems,it brings forward relative solving measures,so as to avoid the cracks happening and improve the capacity requirements of bricking structure.

强调了砌体出现问题在建筑中的危害性，分析了砌体裂缝产生的原因，针对出现的问题提出了相应的解决对策，从而避免裂缝的产生，提高砌体结构的承载力要求。

Horizontal well sectionalized hydraulic fractured technology has been a high speed development as a means of increasing production in low permeability reservoir, but compare to the fracture-extend model, temperature model, surface treatment pressure model, it advanced slowly in the proppant transport model.

水平井分级压裂技术作为水平井开发的低渗透油气藏主要的增产改造的工艺措施，受到了国内外各油田的高度重视并得到了长足的发展，但相对于水平井压裂单裂缝的延伸模型、温度场模型、施工压力预测模型来说，在水平井单裂缝的支撑剂输送模型的研究方面却进展缓慢。

This article study the most three factors of influence in pre-splitting blasting , which are powder capacity per meter 、 spacing of hole and decoupling. On the basis of ANSYS/LS-DYNA and establishing 3D model about two pre-splitting holes, numerical value sumilate expanded process of the crack , then estimates effect of the rock crash by analyzing stress , otherwise estimates effect of pre-splitting blasting by expanded picture .

本文研究了预裂爆破中影响最大的三个因素：线装密度、周边眼间距及周边眼的不耦合系数，并利用动力有限元分析软件ANSYS/LS-DYNA，建立两预裂孔爆破的三维模型，数值模拟出预裂爆破裂缝扩展过程，然后通过应力值的分析来判断岩石的破碎情况，另外利用预裂缝的扩展图分析预裂爆破的效果。

According to the cracks produced in aerated concrete block filler wall with frame structure the reasons caused the cracks are systematically analyzed;at the same time from design and construction aspects practicable control measures are proposed in order to eliminate cracks and ensure plastering quality of filler wall .

针对框架结构加气混凝土砌块填充墙墙面抹灰裂缝的现象，系统的分析了裂缝产生的原因，并重点从设计方面、业主方面、施工方面阐述了切实可行的控制措施，有效的保证了加气混凝土砌块填充墙墙面抹灰的质量。

The test result has been described and the causes of differential subsidence on the bottom of test pit have been analyzed from two aspects (deformation of loess collapse and slip and subside of wet soil mass along fracture). On this basis, the article summarized that Surface water and ground fracture in the activities is to promote mutual interaction.

通过对试验的几种不同沉降关系曲线和试坑沉降变形等值线图的描述，文章从可能引起试坑产生不均匀沉降变形的两个方面(黄土湿陷变形、浸湿土体沿裂缝滑移下陷)作了探讨，得出地表水与地裂缝的活动是相互促进相互影响的关系。

The test has been done to simulate the movement of ground fracture after surface water soaking in. The test result has been described and the causes of differential subsidence on the bottom of test pit have been analyzed from two aspects (deformation of loess collapse and slip and subside of wet soil mass along fracture).

通过对试验的几种不同沉降关系曲线和试坑沉降变形等值线图的描述，文章从可能引起试坑产生不均匀沉降变形的两个方面黄土湿(来源：ABC论4c文网www.abclunwen.com陷变形、浸湿土体沿裂缝滑移下陷作了探讨，得出地表水与地裂缝的活动是相互促进相互影响的关系。

The paper adopted the contract model according with the fact, studied the effect of contract condition on reflection cracking, analyzed the main factor of reflection cracking caused by temperature changes.

本文采用了更符合实际情况的接触模型，利用ANSYS 中热分析和接触分析的耦合技术，详细研究了在温度荷载作用下的接触条件对反射裂缝的影响，分析发现了接触条件是产生温度型反射裂缝的主导因素。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。