【正文】
會產(chǎn)生一個縱向壓應(yīng)力分布,從零線性變化,在頂面最大的混凝土應(yīng)力, =,在底部,是從具體的質(zhì)心的距離在哪里底梁,橫截面的慣性的時刻,是梁的深度。 這種強加的縱向力,被稱為 1預(yù)應(yīng)力,即,壓縮力,部分預(yù)應(yīng)力沿跨度的結(jié)構(gòu)型元素之前死和活荷載或暫態(tài)水平活荷載橫向重力的應(yīng)用。在水泥的原料和最終產(chǎn)品的放射性變化,從一個國家到另一個內(nèi)同一類型的材料,從不同的地點。一個專用的軟件程序( 2020)從堪培拉精靈分析每個測量γ射線譜。儀器儀表和校準(zhǔn) 活度測量進行伽瑪射線光譜儀,采用 3“ 3”閃爍探測器。 25個樣品取自原材料(石灰石,粘土,礦渣,氧化鐵,石膏),這是在水泥行業(yè)中使用的所有原材料,最終產(chǎn)品的樣品取自 20艾斯尤特水泥( 波特蘭, ELMohands,白,耐硫酸鹽水泥( SRC)的)。但這些材料在埃及的放射性的信息是有限的。 建材及其組件的無線電元素濃度在人口風(fēng)險評估是重要的,因為大多數(shù)人花費 80%的時間是在室內(nèi)。帕雷德斯等人, 1987 年水泥或原料曝光水泥或它是必要的現(xiàn)實,所以我們應(yīng)該知道的水泥及其原料的放射性原料)的結(jié)果。這些天然放射性核素的活度濃度與其他國家報告的數(shù)據(jù)進行比較。 這也是必須考慮的前景問題,從不同的 房間,和那些在使用中最應(yīng)該盡可能最好朝南。無障礙公共交通已不再是決定性因素,在住房,因為大多數(shù)工人開著自己的車上班的人。一個客廳,一個廚房和廁所,公共建筑,可以在政治文化活動,管理工作和其他服務(wù),如學(xué)校,寫字樓,公園,醫(yī)院,商店,車站,影劇院,體育場館,賓館,展覽館,洗浴池,等等,他們都有不同的功能,這在需要以及不同的設(shè)計類型。 Tzortzis et al., 2020). But information about the radioactivity of these materials in Egypt is limited. Knowledge of the occurrance and concentration of natural radioactivity in such important materials is essential for checking its quality in general and knowing its effect on the environment surrounding the cement producing factories in particular. Because of the global demand for cement as a building material, the present study aims to: (1) Assess natural radioactivity (226Ra, 232Th and 40K) in raw and final products used in the Assiut cement factory and other local factories in Egypt. (2) Calculate the radiological parameters (radium equivalent activity Raeq, level index Iγr, external hazard index Hex and absorbed dose rate) which is related to the external γdose rate. The results of concentration levels and radiation equivalent activities are pared with similar studies carried out in other countries. 2. Experimental technique . Sampling and sample preparation Fifty seven samples of raw materials and final products used in the Assiut cement factories were collected for investigation. Twenty five samples of raw materials were taken from (Limestone, Clay, Slag, Iron oxide, gypsum) which are all the raw material used in cement industry, 20 samples of final products were taken from Assiut cement (Portland, ElMohands, White, and Sulphate resistant cement ()). For parison with products from other factories, 8 samples were taken from the ordinary Portland cement from (Helwan, Qena, Elkawmya, Torra) and 4 samples were taken of white cement (Sinai and Helwan). Each sample, about 1kg in weight was washed in distilled water and dried in an oven at about 110 176。 Kumar et al., 2020。 民用建筑分為兩大類:住宅建筑和公共建筑,住宅建筑應(yīng)滿足家庭生活應(yīng)包括至少有三個必要的房間:每個單位。不少家庭的首選國家住房郊區(qū)住房的大量的,因為他們的主要目的是遠離噪音,擁擠,混亂。連接天與客房的服務(wù)。從測得的γ射線譜,具體活動進行了測定。作業(yè)工人,尤其是在地雷和生產(chǎn)基地以及人們在很長一段時間,大約 80%的時間花在辦公室和家庭內(nèi)( Mollah等人,1986 年。低級別的伽瑪射線熒光光譜儀是適用于環(huán)境中的伽瑪射線發(fā)射核素( IAEA, 1989)定性和定量測定。 Tzortzis 等, 2020)。取樣和樣品制備 在艾斯尤特水泥工廠使用的原材料和最終產(chǎn)品的 57個樣品進行了調(diào)查收集的。 。背景光譜被用來糾正的凈峰面積測量同位素的 γ射線。因此,水泥制品不構(gòu)成重大建筑施工中使用時的輻射危害。的部分,然后能夠表現(xiàn)彈性,幾乎滿負荷生產(chǎn)的混凝土在壓縮,可以有效地利用各地的具體章節(jié)的整個深度時,所有負載結(jié)構(gòu)的行動。 相同卸載梁與預(yù)應(yīng)力強調(diào)高強度的肌腱作用力。 預(yù)應(yīng)力圓形,液體 containmeng坦克,管道,壓力反應(yīng)容器中,基本上遵循相同的基本原則,如不線性預(yù)應(yīng)力。所需的生產(chǎn)預(yù)應(yīng)力成員的預(yù)應(yīng)力鋼積極預(yù)裝的成員,允許一個相對高的開裂和撓度的控制復(fù)蘇。和間接的長期儲蓄是相當(dāng)可觀的,因為需要較少的維護,更長的工作壽命是可能的,因為更好的混凝 土質(zhì)量控制,并實現(xiàn)更輕的基礎(chǔ),由于上層建筑的累計重量較小。 線性預(yù)應(yīng)力繼續(xù)在歐洲和法國發(fā)展,特別是通過別出心裁的尤金的 Freyssi,提出在 1923年至 1928年的方法,通過使用高強度和高延性 ,他介紹了現(xiàn)在眾所周知和公認的 Freyssi系統(tǒng)。預(yù)應(yīng)力損失減少的結(jié)果。這些 20世紀(jì)的發(fā)展,導(dǎo)致在世界各地,特別是美國和預(yù)應(yīng)力的廣泛使用。經(jīng)過一段時間的流逝,在這期間沒有取得什么進展,因為不可用高強度鋼板,克服預(yù)應(yīng)力損失,重新蒔蘿,內(nèi)布拉斯加州,亞歷山德里亞公認的收縮和徐變預(yù)應(yīng)力損失的混凝土材料(橫流)的影響。因此,需要較少的混凝土預(yù)應(yīng)力成員,加固量的約 20%到 35%。鋼筋 混凝土,混凝土的抗拉強度是微不足道的,無視。負載引起的光束偏轉(zhuǎn),創(chuàng)建拉伸應(yīng)力在梁的底部。 首先,由負載引起的緊張局勢將不得不取消的預(yù)應(yīng)力,才可以破解的具體產(chǎn)生壓縮。 預(yù)應(yīng)力混凝土 具體是在壓縮強勁,但在 tesion弱:其拉伸強度變化從 8至 14%,其抗壓強度。 40K的活度濃度低于所有其他國家的相應(yīng)值。為了減少伽瑪射線背景圓柱底部固定和移動蓋( 100 毫米厚的鉛屏蔽)屏蔽探測器。 C,以確保徹底清除水分,對樣品進行粉碎,均質(zhì),并通過 200目,這是最佳的篩分在重礦物富集的大小。 ( 2)計算的放射性參數(shù)(相當(dāng)于鐳活動 Raeq,水平指數(shù) Iγ r,外部危險指數(shù)六角和吸收劑量率),這是關(guān)系到外部的γ劑量率。已支付的高度重視,以確定在許多國家建筑材料放射性核素濃度( Amrani 和 Tahtat, 2020。中 226Ra, 232Th和 40K的原材料和加工的內(nèi)容可以有很大的不同取決于其地質(zhì)源和地球化學(xué)特征。水泥不構(gòu)成重大建筑施工中使用時的輻射危害。 標(biāo)準(zhǔn)化是在工業(yè)大廈內(nèi)的小雖然這些建筑物仍然需要遵守當(dāng)?shù)氐某鞘幸?guī)劃法規(guī),現(xiàn)代趨勢是朝著輕,通風(fēng)的廠房。支付提供這些地區(qū)之間容易溝通。附近的房屋是如何糧店,糧食市場,學(xué)校,商店,圖書館,電影院,社區(qū)中心,家庭也會問。 由于其使用的分類,建筑主要有兩種類型:工業(yè)建筑和民用建筑各工廠或工業(yè)生產(chǎn)中使用的工業(yè)大廈,而那些居住,就業(yè),教育和其他社會活動的人使用的民用建筑。濰坊學(xué)院本科畢業(yè)論文 1 一、原文 building types and design A building is closely bound up with people, for it provides with the necessary space to work and live in . As classified by their use ,buildings are mainly of two types :industrial buildings and civil buildings .industrial buildings are used by various factories or industrial production while civil buildings are those that are used by people for dwelling ,employment ,education and other social activities . Industrial buildings are factory buildings that are available for processing and manufacturing of various kinds ,in such fields as the mining industry ,the metallurgical industry ,machine building ,the chemical industry and the textile industry . factory buildings can be classified into two types singlestory ones and multistory ones .the construction of industrial buildings is the same as that of civil buildings .however ,industrial and civil buildings differ in the materials used and in the way they are used . Civil buildings are divided into two broad categories: residential buildings and public buildings .residential buildings should suit family life .each flat should consist of at least three necessary rooms : a living room ,a kitchen and a toilet .public buildings can be used in politics ,cultural activities ,administration work and other services ,such as schools, office buildings, parks ,hospitals ,shops ,stations ,theatres ,gymnasiums ,hotels ,exhibition halls ,bath pools ,and so on .all of them have different functions ,which in turn require different design types as well. Housing is the living quarters for human beings .the basic function of housing is to provide shelter from the elements ,but people today require much more that of their housing .a family moving into a new neighborhood will to know if the avai