土建英語作業(yè)(中英文對照翻譯).doc

FoundationsAll structures designed to be supported by the earth, including buindings, bridges, earth fills, earth and rock and concrete dams,consist of two parts. These are the superstructure, or upper part, and the substructure element which interfaces the superstructure and supporting ground. In the case of earth fills and dams, there is often not a clear line of demarcation between the superstructure and substructure. The foundation can be defined as the substructure and that adjacent zone of soil and rock which will be affected by both the substructure element and its loads.The foundation engineer is that person who by reason of experience and training can be produce solutions for design problems involving this part of the engineered system. In this context,foundation engineering can be defined as the science and art of applying the principles of soil and structural mechanics together with engineering judgement to solve the interfacing problem.The foundation engineer is concerned directly with the structural members which affect the transfer of load from the superstructure to the soil such that the resulting soil stability and estimated deformations are tolerable.Since the design geometry and location of the substructure element often have an effect on how the soil responds,the foundation engineer must be reasonably versed in structural design. Foundations for structures such as buildings, from the smallest residential to the tallest high-rise, and bridges are for the purpose of transmitting the superstructure load. These loads come from column-type members with stress intensities rangeing from perhaps 140MPa for steel to 10MPa for concrete to the supporting capacity of the soil, which is seldom over 500kPa but more often on the order of 200 to 250kPa. Almost any reasonable structure can be built and safely supported if there is unlimited financing.Unfortunately, in the real situation this is seldom, if ever, the case, and the foundation engineer has the dilemma of making a decision under much less than the ideal condition, Also, even though the mistake may be buried, the results from the error are not and can show up relatively soon-and probably before any statute of limitations expires. These are reported cases where the foundation defects have shown up either during construction of superstructure or immediately thereafter. Since the superstructure is buried, or is beneath the superstructure, in such a configuration that access will be difficult, should foundation inadequacies develop after the superstructure is in place; it is common practice to be conservative. A one or two percent over design, in these areas produces a larger potential investment return than in the superstructure. The designer is always faced with the question of what constitutes a safe , economical design while simultaneously contending with the inevitable natural soil heterogeneity at a site. Nowadays that problem may be compounded by land scarcity requiring reclamation of areas which have been used as sanitary landfills, garbage dumps, or even hazardous waste disposal areas. Still another complicating factor is that the act of construction can alter the soil properties considerably from those used in the initial analyse of the foundation.These factors result in foundation design becoming so subjective and difficult to quantify that two design firms might come up with completely different designs which would perform equally satisfactory. Cost would likely be the distinguishable feature for the preferred design. This problem and the widely differing solutions would depend, for example, on the folling. 1)What constitutes satisfactory and tolerable settlement ; how much extra could, or should , be spent to reduce estimated settlements from say 30 to 15mm? 2)Has the client been willing to authorize an adequate soil exploration program?what kind of soil variability did the soil borings indicate?Would additional borings actually improve the foundation recommendations? 3)Can the buildings be supported by the soil using? 4)What are the consequences of a foundation failure in term of public safety? What is the likelihood of a lawsuit if the foundation does not perform adequately? 5)Is sufficient money available for the foundation? It is not unheard of that the foundation alone would cost so much that the project is not economically feasible. It may be necessary to abandon the site in favor of one where foundation costs are affordable? 6)What is the ability of the local construction force ? It is hardly sensible to design an elaborate foundation if no one can built it, or if it is so different in design that the contractor includes a large uncertainty factor in the bid. 7)What is the engineering ability of the foundation engineer? While this factor is listed last,this is not of least importance in economical design. Obviously engineers have different levels of capability just as in other professions and in the trades such as carpenters, electricians ,and painters. If the foundation fails because of any cost shaving, the client tends to be quickly lose appreciation for the temporary financial benefit which accrued. At this point , facing heavy damages and a lawsuit, the client is probably in the poorest mental state of all the involved parties. Thus, one should always bear in mind that absolute dollar economics may not produce good foundation engineering. The foundation engineer must look at the entire system,the building purpose, probable service-life loading, type of framing, soil profile, construction methods, and construction costs to arrive at a design that is consistent with the client needs and does not excessively degrade the environment . This must be done with a safety factor which produces a tolerable risk to both the public and the owner. Considering these several areas of uncertainty, it follows that risk and liability insurance for persons engaged in foundation engineering is very costly. In attempts to reduce these costs as well as produces a design , which could be obtained from several engineering firms there is active discussion of having the foundation engineer submit the proposed design to a broad of qualified engineers for a peer review. 中文翻譯： 地基基礎(chǔ) 所有由土基礎(chǔ)的結(jié)構(gòu)，包括建筑物，橋梁，土堤，土石壩和混凝土壩，都由兩部分組成，它們是上部結(jié)構(gòu)或者上面的部分和下部結(jié)構(gòu)單元，下部結(jié)構(gòu)介于上部結(jié)構(gòu)和支撐地層之間。對于土堤和壩來說，往往是沒有明確的劃分界限?；A(chǔ)可以定義為下部結(jié)構(gòu)，并且臨近的土和壩收到下部結(jié)構(gòu)單元和它的負(fù)荷的影響。 基礎(chǔ)工程師是，一個憂郁有經(jīng)驗和長期訓(xùn)練的原因，可以提供關(guān)于這部分的工程系統(tǒng)的設(shè)計問題的解決方案的人。在這種情況下，基礎(chǔ)工程可以被定義為應(yīng)用土和結(jié)構(gòu)力學(xué)結(jié)合工程判斷的原則，共同解決類似問題的科學(xué)和藝術(shù)。由于設(shè)計的的幾何形狀和下部結(jié)構(gòu)單元位置往往對土壤有效果，所以基礎(chǔ)工程師在結(jié)構(gòu)設(shè)計中必須合理精通的。 那些建筑物結(jié)構(gòu)的基礎(chǔ)，從最小的住宅，到最高的高層，和橋梁都是以傳遞上層建筑負(fù)荷為目的。這些荷載來自構(gòu)件柱形與構(gòu)件的應(yīng)力強度，也許從140MPa的鋼到10MPa的混凝土。土壤的支撐能力很少超過500kPa，但更多的時候在200250kPa之間。如果工程造價沒有限制的話，幾乎任何合理的結(jié)構(gòu)，都可以建立和安全支撐.但不幸的是，在實際情況中，幾乎是不可能的，如果有這種情況的話也是極少見的，基礎(chǔ)工程師也比理想的條件下更難以作出決定，另外，即使錯誤可以掩埋，結(jié)果也不可以掩埋，可能相當(dāng)快，或許在一切限制性的條例到期之前，就會顯現(xiàn)出來。 這些被報道的案例中基礎(chǔ)缺陷顯現(xiàn)或許在上部結(jié)構(gòu)工程建造期間出現(xiàn)或者緊隨其后的出現(xiàn)。由于上部結(jié)構(gòu)被掩埋，或者上部結(jié)構(gòu)的下方，在這樣的配置下，通道將是困難的，或許基礎(chǔ)缺陷，出現(xiàn)在上部結(jié)構(gòu)之后是合理的地方，它是常見的做法是保守的。如果將設(shè)計值超過的一個或兩個百分點在這些地方，可以比上層建筑產(chǎn)生更大的潛在投資回報。設(shè)計師總是面臨著怎樣構(gòu)成一個安全，經(jīng)濟的設(shè)計，同時關(guān)于不可避免的自然土壤不均勻性的問題的爭論在網(wǎng)站上上演。如今，這一問題可能會由于土地的稀缺而加劇了，在這種情況下要求土地的填海工程已采用衛(wèi)生填埋場，垃圾場，甚至是危險廢物處置領(lǐng)域的地區(qū)。還有一個復(fù)雜因素是，建設(shè)的行為可以從基礎(chǔ)的初始設(shè)計中改變土壤的屬性.這些因素導(dǎo)致基礎(chǔ)設(shè)計變得如此主觀的，難以量化，完全不同的兩個設(shè)計公司可能提出完全不同的設(shè)計方案，但結(jié)果執(zhí)行同樣令