【正文】
計(jì)算得到設(shè)計(jì)年限內(nèi)一個(gè)行車道上的累計(jì)標(biāo)準(zhǔn)軸次約為1200萬(wàn)次左右,根據(jù)規(guī)范推薦結(jié)構(gòu),路面結(jié)構(gòu)面層采用瀝青混凝土(12cm)、基層采用密級(jí)配瀝青碎石(24cm)、底基層采用二灰土(厚度待定)。密級(jí)配瀝青碎石層底: ∴查圖三層連續(xù)體系上層拉應(yīng)力系數(shù)諾謨圖得, , ∴查圖得, , ∴查圖得計(jì)算密級(jí)配瀝青碎石基層容許彎拉應(yīng)力:,底層彎拉應(yīng)力:,∴查圖三層連續(xù)體系中層拉應(yīng)力系數(shù)諾謨圖得:。 查規(guī)范可知:,相應(yīng)的彎拉彈性模量標(biāo)準(zhǔn)值為31GPa。確定可靠度系數(shù)為=.因而,所選普通混凝土面層厚度()可以承受設(shè)計(jì)基準(zhǔn)期內(nèi)荷載應(yīng)力和溫度應(yīng)力的綜合疲勞作用。根據(jù)公路等級(jí),由規(guī)范可知,考慮偏載和動(dòng)載等因素對(duì)路面疲勞損壞影響的綜合系數(shù)。1) 路面材料參數(shù)確定 查規(guī)范可知:,相應(yīng)的彎拉彈性模量標(biāo)準(zhǔn)值為31GPa。確定可靠度系數(shù)為=.因而,所選普通混凝土面層厚度()可以承受設(shè)計(jì)基準(zhǔn)期內(nèi)荷載應(yīng)力和溫度應(yīng)力的綜合疲勞作用。s lives has a very important role. In China39。s highway traffic extremely falls behind, in 1949 the national road was open to traffic the course only 8 0,700kilometers, road density only kilometers / hundred square kilometers. The early years of the new nation, after the highway traffic experiences section of times the restorations to start to obtain the considerable development, in 1952 the road course achieved126,700 kilometers. In the 5039。s first expressway Shanghai Baker Highway ( km) was opened to traffic. Since then, 375 have pleted a total length of the Shenyang Dalian highway km and 143 km along the highway. Entering the 1990s, the National Road Route overall planning and guidance, China to accelerate the pace of highway construction, each of the highway built by the tens of kilometers up to 1,000 kilometers above. As of the end of 1999, national highway mileage reached 11,600 km. 10 short years, China has traversed a highway on the general needs of the developed countries Highway 40 pleted the development process. Expressway and other highgrade highway construction, improvement in the technical level of highway structure, changed the highways of backwardness, but also significantly reduce China and the gap between the developed countries. highway construction problems existFrom a historical perspective, China39。s highways to the backward state. According to statistics, as of 1999, the National Highway mileage reached million km, Road density reaching 14. 1 km / 100 square kilometers, to the one in 1978. five times. 2% above the National Highway length of roads by the end of 1979 1. 3% in 1999 to 12. 5%, between the major cities of road traffic conditions improved significantly, highway traffic initial tensions eased. Meanwhile, the county, township highway mileage of rapid growth, quality has greatly improved, the country achieved a 100% of the counties, and 98% of the rural and 89% of the administrative villages Highway. Overall, a convergence Riganzhi, rational layout, ease of the national road network has initially taken shape. Particularly worth mentioning is the construction of expressways. Expressway construction is the reform and opening up of China39。s history and the current construction of highways issues modern history of highway development China39。附 錄:On highway construction and sustainable developmentAbstract: Highway, is in accordance with the national industry standard highway engineering standard construction, by the highway department in charge of the city finds acceptance, between urban and rural areas, the countryside primarily for the driving of motor vehicles on public roads. Highway development of the national economy39。板長(zhǎng)5m,l/r=,查規(guī)范得普通混凝土板厚h=。 方案三:1)普通混凝土面層厚度為26 cm;,基層選用石灰粉煤灰穩(wěn)定粒料,厚18cm;墊層用低劑量無(wú)機(jī)結(jié)合料穩(wěn)定土,厚15 cm;。復(fù)合式混凝土面層截面總剛度計(jì)算:復(fù)合式混凝土面層的相對(duì)剛度半徑計(jì)算:標(biāo)準(zhǔn)軸載在普通混凝土面層臨界荷位處產(chǎn)生的荷載應(yīng)力計(jì)算:普通混凝土面層,因縱縫為設(shè)拉桿平縫,接縫傳荷能力的應(yīng)力折減系數(shù);碾壓混凝土基層不設(shè)縱縫,不考慮接縫傳荷能力的應(yīng)力折減系數(shù)。板長(zhǎng)5m,l/r=,查規(guī)范得普通混凝土板厚h=。c)初擬路面結(jié)構(gòu)橫斷面根據(jù)規(guī)范:等級(jí)中級(jí)的變異水平為低,根據(jù)高速公路、重交通等級(jí)和低級(jí)變異水平等級(jí), 方案一:普通混凝土面層厚度為27 cm;,基層選用水泥穩(wěn)定粒料,厚18cm;墊層用低劑量無(wú)機(jī)結(jié)合料穩(wěn)定土,厚15 cm;。該公路為高速公路,面層是瀝青混凝土,半剛性基層總厚度大于20cm。水泥碎石層底: ∴查圖三層連續(xù)體系上層拉應(yīng)力系數(shù)諾謨圖得, , ∴查圖得, , ∴查圖得計(jì)算水泥碎石底基層容許彎拉應(yīng)力:,底層彎拉應(yīng)力:,∴查圖三層連續(xù)體系中層拉應(yīng)力系數(shù)諾謨圖得:。累計(jì)當(dāng)量軸次:::: 由上面的計(jì)算得到設(shè)計(jì)年限內(nèi)一個(gè)行車道上的累計(jì)標(biāo)準(zhǔn)軸次約為722萬(wàn)次左右,根據(jù)規(guī)范推薦結(jié)構(gòu),路面結(jié)構(gòu)面層采用瀝青混凝土(15cm)、基層采用水泥碎石(25cm)、底基層采用石灰土(厚度待定)。5 公路路面結(jié)構(gòu)設(shè)計(jì)計(jì)算安康至達(dá)州兩地之間修建一條高速公路,%,該路段處于v1區(qū), 組成巖石是古生界片巖、千枚巖、板巖、花崗巖、砂巖及石灰?guī)r。漿砌片石墻身應(yīng)在墻前地面以上設(shè)一排泄水孔。當(dāng)凍深超過1m時(shí),但基底應(yīng)夯實(shí)一定厚度的砂礫或碎石墊層。同理在k2+600到k+2680段內(nèi)同樣設(shè)置路肩墻。重力式擋土墻依靠墻身自重支撐土壓力來(lái)維持其穩(wěn)定。1) 中央分隔帶排水設(shè)施由縱向排水溝(明溝、暗溝)、滲溝、雨水井、集水井、橫向排水管等組成。、截水溝、排水溝、跌水井,渡水槽和急流槽,各類地段排水溝應(yīng)高出設(shè)計(jì)水位0~2m以上。2) 路堤基底范圍內(nèi)由于地表水或地下水影響路基穩(wěn)定時(shí),應(yīng)采取攔截,引排等措施,或在路堤底部填筑不易風(fēng)化的片石,塊石或砂、礫等透水性材料。橋涵臺(tái)背和擋土墻墻背填料,應(yīng)優(yōu)先選用內(nèi)摩檫角值較大的礫(角礫)類土,砂類土填筑。計(jì)算調(diào)運(yùn)數(shù)量和運(yùn)距調(diào)配的運(yùn)距是指計(jì)價(jià)運(yùn)距,就是調(diào)運(yùn)挖方中心到填方中心的距離見區(qū)免費(fèi)運(yùn)距、廢方數(shù)量和總運(yùn)量: 借方數(shù)量=填缺—縱向調(diào)入本樁的數(shù)量廢方數(shù)量=挖余—縱向調(diào)出本樁的數(shù)量總運(yùn)量=縱向調(diào)運(yùn)量+廢方調(diào)運(yùn)量+借方調(diào)運(yùn)量橫向調(diào)運(yùn)復(fù)核:填方=本樁利用+填缺挖方=本樁利用+挖余縱向調(diào)運(yùn)復(fù)核:填缺=縱向調(diào)運(yùn)方+借方挖余+縱向調(diào)運(yùn)方+廢方總調(diào)運(yùn)量復(fù)核:挖方+借方=填方+借方以上復(fù)核一般是按逐頁(yè)小計(jì)進(jìn)行的,最后應(yīng)按每公里合計(jì)復(fù)核。回頭曲線路段的土石調(diào)運(yùn),要優(yōu)先考慮上下線的豎向調(diào)運(yùn)。 超高過渡段僅在回旋線上的某一區(qū)段上進(jìn)行。為抵消車輛在曲線路線上行駛時(shí)所產(chǎn)生的離心力,將路面做成外側(cè)高于內(nèi)側(cè)的單向橫坡的形式,這就是曲線上的超高。本設(shè)計(jì)路段地處平原微丘區(qū),故宜采用梯形邊溝,內(nèi)側(cè)邊坡坡度為1:1。高速公路以小客車為折算標(biāo)準(zhǔn)。豎曲線設(shè)計(jì),首先確定合適的半徑。要注意保持技術(shù)指標(biāo)均衡,位置組合合理適當(dāng),盡量避免不良組合情況。如選擇高填深挖、擋土墻、重要橋涵及人工構(gòu)造物以及其它重要控制點(diǎn)的斷面等。以點(diǎn)定線就是按照縱面技術(shù)標(biāo)準(zhǔn)的要求,滿足“控制點(diǎn)”,參考“經(jīng)濟(jì)點(diǎn)”,初步定出坡度線,然后用三角板推平行線的辦法,移動(dòng)坡度線,反復(fù)試坡,對(duì)各種可能的坡度線方案進(jìn)行比較,最后確定既符合標(biāo)準(zhǔn),又保證控制點(diǎn)要求,而且土石方量最省的坡度線,將其延長(zhǎng)交出變坡點(diǎn)初步位置。該路地處平原區(qū),土地資源寶貴,本項(xiàng)縱斷面設(shè)計(jì)采用小縱坡,微起伏與該區(qū)域農(nóng)田相結(jié)合,盡量降低路堤高度,路線縱斷面按百年一遇,設(shè)計(jì)洪水位的要求和確保路基處于干燥和中濕狀態(tài),所需的最小填筑高度來(lái)控制標(biāo)高,線形設(shè)計(jì)上避免出現(xiàn)斷背曲線,反向豎曲線之間直線長(zhǎng)度不足3秒行程的則加大豎曲線半徑,使豎曲線首尾相接。4) 平面與橫斷面的綜合協(xié)調(diào)主要是超高的設(shè)計(jì)。b) :確定路基寬度時(shí),中央分隔帶寬度、左側(cè)路緣帶寬度、右側(cè)硬路肩寬度、土路肩寬度等的“一般值”和“最小值”應(yīng)同類項(xiàng)相加。涵洞及通道的標(biāo)高確定:涵洞在1km內(nèi)設(shè)置一到兩個(gè),涵底標(biāo)高為地面標(biāo)高且考慮流水,通道考慮原有路面標(biāo)高加上凈空要求及留1m左右涵洞高所確定的。對(duì)原有鄉(xiāng)村道路采用上跨方式。同理在k2+600到k+2680段內(nèi)同樣設(shè)置路肩墻。在路線設(shè)計(jì)的基礎(chǔ)上完成以下工作:路基、排水、防護(hù)、支擋工程、特殊路基等設(shè)計(jì);路面工程設(shè)計(jì)(路面的結(jié)構(gòu)組合設(shè)計(jì)、厚度設(shè)計(jì)與方案比選)。路面設(shè)計(jì)中,從經(jīng)濟(jì)實(shí)用的角度,對(duì)剛性路面和柔性路面進(jìn)行了了比較,最終選擇了瀝青混凝土路面。同時(shí)本設(shè)計(jì)體現(xiàn)環(huán)保意識(shí),強(qiáng)調(diào)環(huán)保。,充分考慮平縱組合平衡和填挖平衡的原則,對(duì)沿線地形、地質(zhì)、水文、排水等綜合考慮,全線共設(shè)4個(gè)豎曲線,%,%。5. 路面結(jié)構(gòu)設(shè)計(jì)以雙輪組單軸軸載100KN為標(biāo)準(zhǔn)軸載,選用瀝青混凝土路面。6號(hào)橋和7號(hào)橋之間有三條鄉(xiāng)村道路,稱為1,2,3號(hào)路,2號(hào)路是從1號(hào)路分離出去的,3號(hào)路距離2號(hào)路距離40米,距離7號(hào)橋87米左右,考慮高速公路盡量減少縱橫向干擾,將2,3號(hào)路與1號(hào)路合并。 考慮第二種方案:終點(diǎn)可以若是向上移動(dòng)些可以避過房屋和雞舍等,但是在交點(diǎn)1附近的路線將移到小山邊上,造成較大的挖方量,日后將要采取挖方通過,但與拆遷雞舍房屋相比較,考慮到挖方所得的土石可以用來(lái)鋪填路基,而且路線距離較陡的部分距離最小有20米,路線從緩坡處可以安全通過,決定采取終點(diǎn)上移的路線走向。在海拔2000m以上或積雪冰凍地區(qū)的四級(jí)公路,最大縱坡不大于8%。3) 注意綠化,對(duì)路基邊坡及中央分隔帶加強(qiáng)綠化和防護(hù),在護(hù)坡道上互通立交用地范圍內(nèi)的空地上均考慮綠化。:縱坡設(shè)計(jì)前,應(yīng)先根據(jù)中樁和水準(zhǔn)記錄點(diǎn),繪出路線縱斷面圖的地面線繪出平面直線,曲線示意圖,寫出每個(gè)中樁的樁號(hào)和地面標(biāo)高以及土壤地質(zhì)說(shuō)明資料,并熟悉和掌握全線有關(guān)勘測(cè)設(shè)計(jì)資料,領(lǐng)會(huì)設(shè)計(jì)意圖和要求。若有脫離實(shí)際情況或考慮不周現(xiàn)象,則應(yīng)全面分析,找出原因,權(quán)衡利弊,決定取舍;⑵對(duì)照技術(shù)標(biāo)準(zhǔn)。坡度值一般是用三角板推平行線法,直接讀厘米格子得出,要求取值到千分之一。4) 小橋涵上允許設(shè)計(jì)豎曲線,為保證路線縱面平順,應(yīng)盡量避免出現(xiàn)