【摘要】：隨著經(jīng)濟(jì)的迅猛發(fā)展以及工程技術(shù)的不斷進(jìn)步,一大批超長(zhǎng)混凝土結(jié)構(gòu)不斷涌現(xiàn)出來,而建筑物由于受到季節(jié)溫度變化的影響,產(chǎn)生裂縫十分常見,并且地下建筑有防水要求,一旦墻板開裂造成滲漏其危害性很大。所以,對(duì)混凝土結(jié)構(gòu)裂縫控制的問題,成為現(xiàn)今關(guān)注的重點(diǎn)。本文首先介紹了關(guān)于超長(zhǎng)混凝土結(jié)構(gòu)溫度場(chǎng)和溫度應(yīng)力的基本理論。其次,本文以沈陽(yáng)市環(huán)境溫度為研究背景,采用環(huán)境溫度應(yīng)力分析理論,借助ANSYS有限元軟件,運(yùn)用三維有限元模型線彈性分析方法,建立超長(zhǎng)地下室結(jié)構(gòu)簡(jiǎn)化模型。在進(jìn)行超長(zhǎng)地下室結(jié)構(gòu)簡(jiǎn)化模型環(huán)境溫度作用分析時(shí),所施加的溫度荷載主要是氣溫驟降下的室內(nèi)外最不利溫差,不考慮其收縮的影響。然后進(jìn)行有限元線彈性分析,得出了墻板內(nèi)的溫度應(yīng)力分布規(guī)律。并進(jìn)一步研究分析了墻長(zhǎng)、墻高、墻厚、覆土厚度、內(nèi)外溫差以及混凝土強(qiáng)度變化對(duì)地下室墻板溫度應(yīng)力的產(chǎn)生范圍和分布規(guī)律的影響。在上述工作的基礎(chǔ)上取得的研究成果主要有：(1)地下室側(cè)墻,沿墻體長(zhǎng)度方向墻體為中截面溫度應(yīng)力大,并向兩端逐漸減小分布,而沿高度方向則為下部大向上逐漸減小分布,并且短墻的溫度應(yīng)力很小。經(jīng)分析得溫度應(yīng)力易出現(xiàn)在尺寸較長(zhǎng)的方向上。底板應(yīng)力集中在板中央向四周擴(kuò)散,一般為壓應(yīng)力,較不容易出現(xiàn)裂縫；(2)溫度應(yīng)力隨墻長(zhǎng)逐漸增加,但是最后趨近于一個(gè)定值(3)隨墻體高度的增加,溫度應(yīng)力逐漸減小,即墻體高度和最大應(yīng)力成反比；(4)隨墻體厚度的增加溫度應(yīng)力逐漸減小,底板對(duì)薄墻的約束較大,所以墻體越薄對(duì)溫度應(yīng)力越敏感。根據(jù)此規(guī)律,可對(duì)薄墻采取一定的保溫措施,從而減小溫度拉應(yīng)力；(5)覆土對(duì)地下室墻體具有保溫隔熱的作用,能減少環(huán)境溫度應(yīng)力對(duì)結(jié)構(gòu)的影響；(6)在墻體長(zhǎng)度為30m時(shí),改變其溫差得知,在溫差較小時(shí)墻體的應(yīng)力在整個(gè)墻體上變化不大。當(dāng)溫差大于40℃時(shí),墻體從30m～100m最大的溫度應(yīng)力值一般都大于混凝土抗拉強(qiáng)度標(biāo)準(zhǔn)值。因此對(duì)溫差的控制對(duì)地下室墻體很重要；(7)混凝土強(qiáng)度越高則結(jié)構(gòu)受環(huán)境溫度效應(yīng)影響就越敏感產(chǎn)生的溫度應(yīng)力就越大。最后,本文從分析結(jié)果出發(fā),在材料、設(shè)計(jì)構(gòu)造以及施工措施等方面介紹了地下室超長(zhǎng)混凝土結(jié)構(gòu)裂縫控制的一些技術(shù)措施。
[Abstract]:With the rapid development of economy and the continuous progress of engineering technology, a large number of super-long concrete structures continue to emerge, and due to the influence of seasonal temperature changes, cracks are very common in buildings, and underground buildings have waterproof requirements, once the crack of wallboards causes great harm to leakage. Therefore, the crack control of concrete structures has become the focus of attention. In this paper, the basic theory of temperature field and temperature stress of super-long concrete structure is introduced. Secondly, based on the environmental temperature of Shenyang, the simplified model of super-long basement structure is established by using the theory of ambient temperature stress analysis, with the help of ANSYS finite element software and the linear elastic analysis method of three-dimensional finite element model. In the analysis of the ambient temperature action of the simplified model of super-long basement structure, the temperature load applied is mainly the most unfavorable temperature difference between indoor and outdoor under the sudden drop of temperature, regardless of the influence of shrinkage. Then the finite element linear elastic analysis is carried out, and the distribution law of temperature stress in the wallboard is obtained. The effects of wall length, wall height, wall thickness, overlying soil thickness, internal and external temperature difference and concrete strength on the generation range and distribution of temperature stress of basement wall panel are further studied and analyzed. On the basis of the above work, the main research results are as follows: (1) in the basement side wall, the temperature stress of the middle section is large along the length of the wall, and the distribution decreases gradually to both ends, while the distribution decreases gradually along the height direction, and the temperature stress of the short wall is very small. It is found that the temperature stress is easy to appear in the direction of long size. The stress of the floor is concentrated in the center of the plate and diffuses around, generally compressive stress, which is not easy to crack. (2) the temperature stress increases gradually with the length of the wall, but finally approaches a fixed value (3) with the increase of the height of the wall, the temperature stress decreases gradually, that is to say, the height of the wall is inversely proportional to the maximum stress; (4) with the increase of the thickness of the wall, the temperature stress decreases gradually, and the constraint of the bottom plate to the thin wall is greater, so the thinner the wall is, the more sensitive it is to the temperature stress. According to this law, some thermal insulation measures can be taken for the thin wall, so as to reduce the temperature tensile stress; (5) the overlying soil has the effect of heat preservation and heat insulation on the basement wall, which can reduce the influence of the ambient temperature stress on the structure; (6) when the length of the wall is 30m, the temperature difference of the wall shows that the stress of the wall does not change much on the whole wall when the temperature difference is small. When the temperature difference is more than 40 鈩，

本文編號(hào)：2501461