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will have to slow to 172 mph (277 kph). He will have a reserve parachute that will open automatically if he loses consciousness at mach speeds. Even if everything goes as planned, it won39。s like the set for a Gee Lucas movie floating to the edge of space. You and I will have the chance to watch a man take a leap into an unimaginable free fall from the edge of space live. The (lack of) air up there Watch man jump from 96,000 feet Tuesday, I sat at work glued to the live stream of the Red Bull Stratos Mission. I watched the balloons positioned at different altitudes in the sky to test the winds, knowing that if they would just line up in a vertical straight line we would be go for launch. I feel this mission was created for me because I am also a journalist and a photographer, but above all I live for taking a leap of faith the feeling of pushing the envelope into uncharted territory. The guy who is going to do this, Felix Baumgartner, must have that same feeling, at a level I will never reach. However, it did not stop me from feeling his pain when a gust of swirling wind kicked up and twisted the partially filled balloon that would take him to the upper end of our atmosphere. As soon as the 40acre balloon, with skin no thicker than a dry cleaning bag, scraped the ground I knew it was over. How claustrophobia almost grounded supersonic skydiver 專業(yè)好文檔 30 With each twist, you could see the wrinkles of disappointment on the face of the current record holder and cap (capsule munications), Col. Joe Kittinger. He hung his head low in mission control as he told Baumgartner the disappointing news: Mission aborted. The supersonic descent could happen as early as Sunday. The weather plays an important role in this mission. Starting at the ground, conditions have to be very calm winds less than 2 mph, with no precipitation or humidity and limited cloud cover. The balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our daytoday weather lives. It will climb higher than the tip of Mount Everest ( miles/ kilometers), drifting even higher than the cruising altitude of mercial airliners ( miles/ kilometers) and into the stratosphere. As he crosses the boundary layer (called the tropopause), he can expect a lot of turbulence. The balloon will slowly drift to the edge of space at 120,000 feet ( miles/ kilometers). Here, Fearless Felix will unclip. He will roll back the door. Then, I would assume, he will slowly step out onto something resembling an Olympic diving platform. Below, the Earth bees the concrete bottom of a swimming pool that he wants to land on, but not too hard. Still, he39。d hear my foot tapping rapidly under my desk. I39。s first satellite Sputnik. I also missed watching Neil Armstrong step foot on the moon and the first space shuttle take off for the stars. Those events were way before my time. As a kid, I was fascinated with what goes on in the sky, and when NASA pulled the plug on the shuttle program I was heartbroken. Yet the privatized space race has renewed my childhood dreams to reach for the stars. As a meteorologist, I39。 專業(yè)好文檔 29 Editor39。 ( 6)工程建設(shè)時(shí)應(yīng)按有關(guān)河道管理規(guī)定和要求辦理手續(xù),出現(xiàn)具體問題應(yīng)及時(shí)同有關(guān)部門聯(lián)系,協(xié)調(diào)解決。 ( 5)建設(shè)項(xiàng)目建在 石榴河兩 岸,在施工期完成后,應(yīng)保證河道防汛搶險(xiǎn)通道通暢,以不影響原有防汛搶險(xiǎn)通道為原則。 ( 4)工程施工應(yīng)盡量安排在非汛期進(jìn)行,施工機(jī)械、施工材料等汛前 要 進(jìn)行清理,使施工場(chǎng)地恢復(fù)原貌,工程施工基本對(duì)河道行洪專業(yè)好文檔 28 沒有影響。 ( 3) 目前,石榴河河道治理尚在可研階段,華北物流在廠區(qū)河段建橋和護(hù)坡應(yīng)與未來(lái)石榴河的治理工程相結(jié)合,避免因方案不同進(jìn)行了返工造成經(jīng)濟(jì)損失。需要重新制定設(shè)計(jì)方案。 石榴河年久失修,河道淤積嚴(yán)重,行洪能力已達(dá)不到 5 年一遇防洪標(biāo)準(zhǔn)。 專業(yè)好文檔 27 5 結(jié)論及建議 ( 1) 某項(xiàng)目 二期工程 位于 唐山市開平區(qū)西塔頭村西石榴 河 兩 岸,為保證河道行洪暢通和工程安全,根據(jù)《中華人民共和國(guó)水法》、《中華人民共和國(guó)防洪法》等法律法規(guī)的有關(guān)規(guī)定,對(duì)工程進(jìn)行防洪影響評(píng)價(jià)是必要的。 對(duì)第三人合法水事權(quán)益的影響分析 按原設(shè)計(jì)方案,項(xiàng)目建成后,不能滿足行洪要求,對(duì)上游 300m左右兩岸村莊及建筑物均有影響,原設(shè)計(jì)方案不可行。 建設(shè)項(xiàng)目防御洪澇的設(shè)防標(biāo)準(zhǔn)與措施是否適當(dāng) 按照 建設(shè)項(xiàng)目的規(guī)模和和遭受洪災(zāi)后的 損失和影響程度,以及災(zāi)后恢復(fù)生產(chǎn)能力, 依據(jù)中華人民共和國(guó)《防洪標(biāo)準(zhǔn)》確定建設(shè)項(xiàng)目設(shè)專業(yè)好文檔 26 防標(biāo)準(zhǔn)為 20 年一遇。遇超 20 年一遇洪水時(shí), 人員及可移動(dòng)設(shè)備、設(shè)施可以及時(shí)撤離到附近 較 高地帶。 二期工程 僅對(duì)項(xiàng)目所在河段附近有限范圍內(nèi)產(chǎn)生影響, 尤其是對(duì)上游 300m 左右范 圍影響較大, 對(duì)整個(gè)河段行洪能力和河道上的防洪工程、橋涵等河道設(shè)施影響不大,也不會(huì)影響整個(gè)河道的原有堤防工程的安全和防洪能力。華北物流二期工程的建橋方案,擬建橋長(zhǎng) 16m,比原斷面上口縮窄了 24m,形成卡口斷面,達(dá)不到河道防洪要求,需重新制定建設(shè)方案。經(jīng)計(jì)算,建設(shè)項(xiàng)目所在河段 20 年一遇洪水時(shí)洪峰流量為 189m3/s,現(xiàn)狀該河道未能達(dá)到 5 年一遇的防洪標(biāo)準(zhǔn),該項(xiàng)目實(shí)施后,將進(jìn)一步束窄河道斷面,降低河道行洪能力,影響行洪安全,原設(shè)計(jì)橋長(zhǎng) 16m 的方案不可行,應(yīng)規(guī)劃新的建設(shè)方案,使自身的防洪達(dá)到規(guī)定標(biāo)準(zhǔn),且不降低上游河段的行洪能 力。 與現(xiàn)有防洪標(biāo)準(zhǔn)適應(yīng)性分析 、 對(duì)行洪安全的影響分析 根據(jù) 中華人民共和國(guó)《防洪標(biāo)準(zhǔn)》 ( GB5020194,國(guó)家技術(shù)監(jiān)督局和建設(shè)部 95 年 6 月聯(lián)合發(fā)布)和 業(yè)主提供的《 某項(xiàng)目 項(xiàng)目簡(jiǎn)介 》,按照企業(yè)規(guī)模和遭受洪災(zāi)后的損失和影響程度,以及災(zāi)后恢復(fù)生產(chǎn)能力,確定該企業(yè)防洪標(biāo)準(zhǔn) 為 20 年一遇。項(xiàng)目建設(shè)符合開平區(qū)城市建設(shè)總體規(guī)劃要求,本項(xiàng)目建成后,可為當(dāng)?shù)貏?chuàng)造就業(yè)機(jī)會(huì)和稅收收入,促進(jìn)當(dāng)?shù)亟?jīng)濟(jì)發(fā)展。 跳河橋和兩岸堤坡應(yīng)由有設(shè)計(jì)資質(zhì)的設(shè)計(jì)部門進(jìn)行設(shè)計(jì),并考慮因建橋致使河道行洪斷面縮窄、水位壅高對(duì)上游兩岸的影響,建設(shè)單位在設(shè)計(jì)和修建橋梁時(shí),除滿足建設(shè)項(xiàng)目自身防洪標(biāo)準(zhǔn)外,還應(yīng)對(duì)上游壅水區(qū)范圍 內(nèi)兩岸堤防重新 設(shè)計(jì)和修建,使上游防洪標(biāo)準(zhǔn)不因本項(xiàng)目建設(shè)而降低。 經(jīng)過(guò)水文計(jì)算,建設(shè)項(xiàng)目所在河段 20年一遇洪峰流量為 189m3/s,通過(guò)對(duì)項(xiàng)目所在河段上、中、下三個(gè) 斷面現(xiàn)狀以及工程實(shí)施后形成的新河道斷面計(jì)算,均無(wú)法滿足 20 年一遇防洪要求,擬建橋長(zhǎng) 16m 的方案不可行??傊?,在河床糙率為 ,水面比降為 ‰的前提下,斷面條件必須達(dá)到 16732 ?AR ,并有一段較長(zhǎng)的河槽,才能使河道行洪能力達(dá)到 189 m3/s,滿足 20 年一遇行洪要求。 以上只是根據(jù)河道斷面現(xiàn)狀提出的一個(gè)方案,要求河寬達(dá)到40m。 考慮波浪爬高,風(fēng)壅增水高度和安全超高,安全超高采用 。 擬建橋處原河床斷面寬 ,右岸頂高程 ,左岸邊頂高程 ,河底高程 ,在原斷面的基礎(chǔ)上,對(duì)河道進(jìn)行整治,容易形成上寬 40m,底寬 26m,兩岸頂高程 ,河底高程 10m,邊坡比為 1:2 新斷面,見圖 34,圖中虛線即是要整治的目標(biāo)斷面線 。當(dāng)設(shè)計(jì)洪峰流量、水面比降和河床糙率確定之后,從公式 38 可以看出,斷面條件需滿足:2132IQnAR ? 。該工程的實(shí)施只能對(duì)石榴河部分河段進(jìn)行整治,在整條河流未進(jìn)行治理前,降低部分河段的河底高程是沒有意義的。可見在石榴河久未整治年久失修的情況下,繼續(xù)束窄河道是無(wú)法滿足防洪要求的。 上面只是分析計(jì)算了上中下 3 個(gè)斷面的最大過(guò)水能力,實(shí)際上,由于斷面兩岸高程均超過(guò) 14m,而中斷面右岸高程只有 ,上斷面右岸高程只有 ,當(dāng)下斷面水位平槽時(shí),中、上斷面處的洪水早已出槽,整個(gè)河段的過(guò)水能力將更小。 專業(yè)好文檔 17 根據(jù)上、中、下 3 個(gè)斷面的實(shí)測(cè)成果,同時(shí)因河道內(nèi)樹木較多,糙率取 ,按公式( 38)計(jì)算了各斷面不同水位的斷面面積和輸水率,繪制了 ZA, ZK 關(guān)系曲線,見圖 3 3 33。由于兩者只是比較接近,只能作定性的比較,華北物流擬建橋斷面的洪峰模數(shù)略大于司各莊,說(shuō)明設(shè)計(jì)洪峰流量是基本可靠的。 表 33 洪峰 模數(shù)比較 表 單位: m3/ 重現(xiàn)期( a) 斷面位置 5 10 20 小青龍河 司各莊 石榴河 華北物流擬建橋 從表 33 中可以看出 ,華北物流擬建橋斷面的洪峰模數(shù)大于司各莊,這是因?yàn)樾∏帻?河是平原河流,河槽比降較小,而石榴河發(fā)專業(yè)好文檔 16 源于丘陵區(qū),河槽比降相對(duì)較大。小青龍河流經(jīng)灤縣南部、灤南和唐海,系平原河流,司各莊集水面積 219km2。 洪峰模數(shù)的比較 由于石榴河上無(wú)可供分析的實(shí)測(cè)洪峰流量資料,只能同氣候因素及流域特征比較接近的小青龍河司各莊水文站的實(shí)測(cè)洪峰模數(shù)進(jìn)行比較。這是因?yàn)閱我蜃庸街豢紤]了集水面積因素,經(jīng)驗(yàn)性較強(qiáng),而另兩個(gè)公式,除集水面積因素外還考慮了暴雨、河流特征等成因因素,應(yīng) 更符合實(shí)際。 35 式中的匯流參數(shù) m 為: ??m ( 37) 式中:4131FJL