【正文】 以便將雨雪水及時(shí)排除。城市道路根據(jù)城市道路系統(tǒng)中的地位和交通功能，分為快速路，主干路，次干路，支路。因此,在大力發(fā)展城市經(jīng)濟(jì)的同時(shí),必須將安全意識(shí)引入道路的設(shè)計(jì)中,通過(guò)加強(qiáng)科學(xué)合理的道路設(shè)計(jì),來(lái)有效地控制交通安全,實(shí)現(xiàn)城市社會(huì)的安全和平。對(duì)于道路上的排水設(shè)施要經(jīng)常的檢查和維護(hù),不能使雨天的積水對(duì)道路的交通有一定的影響。在交通事故發(fā)生的地點(diǎn)中,發(fā)生在交叉口的事故比例是相當(dāng)高的。平面線形設(shè)置是否合理,是否適合駕駛員的心理、視覺(jué)和習(xí)慣,是交通安全的一個(gè)重要因素?？v斷面設(shè)計(jì)必須滿足視距要求。阻車(chē)區(qū)內(nèi)砂礫厚度不小于30 cm, 應(yīng)保持松散狀態(tài),不必壓實(shí)。平縱組合設(shè)計(jì)應(yīng)綜合考慮汽車(chē)動(dòng)力學(xué)、駕駛員視覺(jué)和心理方面要求、路面排水要求等,以提供給道路用戶良好的駕駛環(huán)境。視線誘導(dǎo)設(shè)施應(yīng)根據(jù)公路線形、路側(cè)危險(xiǎn)程度和其他設(shè)施的應(yīng)用情況選擇合理的設(shè)施形式。思考題？答：是越小越好，上坡時(shí)燃油的內(nèi)能大部分轉(zhuǎn)變?yōu)闊崮?，坡度越小越?jié)省能源，爬起來(lái)越省力。根據(jù)道路在城市道路系統(tǒng)中的地位、作用、交通功能以及對(duì)沿線建筑物的服務(wù)功能，我國(guó)目前將城市道路分為四類(lèi)：快速路、主干路、次干路及支路。城市交通工具種類(lèi)繁多，速度快慢懸殊，為了避免互相阻礙干擾,要組織分道行駛,用隔離帶、隔離墩、護(hù)欄或劃線方法加以分隔。由于城市道路具有的公共性、公益性、交通特殊性，其與公路、林區(qū)道路、鄉(xiāng)村道路等相比具有其特殊性，這主要表現(xiàn)在：，城市道路不同其他道路，在進(jìn)行道路設(shè)計(jì)時(shí)不僅涵蓋電力管道、排水管道、道路照明、綠化等其他道路具備的要素外，還要涵蓋供熱、燃?xì)?、排污等要素。此外，城市道路的設(shè)計(jì)速度較低，一般不超過(guò)60Km/h。這樣，不僅能夠?qū)崿F(xiàn)城市道路的安全性和合理性，還能將城市道路建設(shè)為舒適、宜人、通暢的交通承載體，進(jìn)而實(shí)現(xiàn)現(xiàn)代城市的可持續(xù)發(fā)展。在城市道路施工設(shè)計(jì)時(shí)要充分的考慮路權(quán)分配問(wèn)題，綜合考慮路上行人、機(jī)動(dòng)車(chē)和非機(jī)動(dòng)車(chē)的交通運(yùn)行方式，并據(jù)此對(duì)不同的交通運(yùn)行體劃分合理的道路權(quán)限，實(shí)現(xiàn)道路資源分配的合理和公平，保障各交通運(yùn)行體的安全。生活性道路更多地考慮了人的需求，如人行道、人行橫道、公交車(chē)專用道等，實(shí)現(xiàn)了人車(chē)分離，在進(jìn)行生活性道路規(guī)劃時(shí)要細(xì)致入微，合理布局，增設(shè)各類(lèi)道路管理設(shè)施控制車(chē)流和車(chē)速，以便滿足行人的安全性和有效空間，創(chuàng)造出安全、舒適、宜人的道路交通環(huán)境。城市道路是交通的直接載體,道路橫斷面是道路的平、縱、橫三要素設(shè)計(jì)的有效組成部分。具體表現(xiàn)在以下方面:道路上行駛車(chē)種的典型變化是小汽車(chē)日益增多；貨車(chē)白天流量減少,夜間大貨車(chē)及特大型集裝箱車(chē)增多；自行車(chē)逐漸減少,摩托車(chē)數(shù)量可觀；隨著人們生活水平的提高,道路的步行、休閑功能日益增強(qiáng)。但我國(guó)城市道路橫斷面規(guī)劃設(shè)計(jì)在理清功能、分期實(shí)施、機(jī)非分流、保護(hù)城市特色等方面存在不少問(wèn)題,很難保障城市交通與城市特色的可持續(xù)發(fā)展。注重道路功能設(shè)計(jì),提高城市道路的宜人氛圍城市道路橫斷面分配必須體現(xiàn)不同類(lèi)別交通在不同類(lèi)別道路上的優(yōu)先級(jí)差異,從快速路到支路,行人、自行車(chē)優(yōu)先級(jí)應(yīng)越來(lái)越高,但小汽車(chē)等機(jī)動(dòng)車(chē)優(yōu)先級(jí)需愈來(lái)愈低。一般而言,道路等級(jí)越高,所需布設(shè)的管線就越多,對(duì)路側(cè)帶、非機(jī)動(dòng)車(chē)道的寬度要求就愈大,所以在道路橫斷面設(shè)計(jì)時(shí)這些寬度尺寸往往是由管線布置而不是交通的需要決定的。合理確定機(jī)動(dòng)車(chē)車(chē)道寬度,節(jié)約道路用地資源,降低工程造價(jià)。所以，咋拼接的時(shí)候，要認(rèn)真考慮到正交或較大角度斜交，最小交角不宜小于45176。交叉口應(yīng)盡量選擇在水平坡段上，如條件限制，亦應(yīng)設(shè)在平緩坡段上。這種方法的銜接點(diǎn)位置及銜接斷面與順坡法一樣的，區(qū)別在于銜接點(diǎn)后的線路縱坡不采用接既有路的路面橫坡進(jìn)行順坡而是以銜接點(diǎn)為變坡點(diǎn)，采用平坡或較緩的上坡為銜接縱坡。平交口立面設(shè)計(jì)主要是按照縱斷面，道路橫坡進(jìn)行設(shè)計(jì)，再設(shè)計(jì)的時(shí)候要盡量使路面等高線圓滑，不要有棱角突出，在車(chē)道轉(zhuǎn)彎的時(shí)候想到車(chē)道橫坡方向及大小，同時(shí)還要想到被交路是新建筑的道路還是老道路的問(wèn)題，更要想到交叉口排水的問(wèn)題。在設(shè)計(jì)的時(shí)候，切記一定要有一個(gè)道路的縱坡方向背離交叉口，去目的是有利于排出水。綜上所述,在路面大修及改擴(kuò)建工程中均會(huì)遇到縱斷面設(shè)計(jì)指標(biāo)難以達(dá)到,如強(qiáng)制執(zhí)行時(shí)可能會(huì)影響結(jié)構(gòu)安全、增加不必要的造價(jià)等問(wèn)題但從使用要求上又必須滿足行車(chē)平穩(wěn)、舒適且不影響交通安全等要求, road engineeringCity road is a certain technical conditions and facilities in the city within the to the road in the city road system status, function, traffic function and service function of the buildings along the city road, at present in our country will be divided into four categories: expressway, trunk road, secondary road and branch to be road connection between the city various activity centers, to shorten the distance running major part of the city to have road access, to facilitate the residents are concentrated in the city road within the limited area of the city, arranged in a crisscross pattern reticular formation, there are many influences the intersection of road traffic flow intersection, So it is necessary to take various measures, such as setting the color light signal control, ring cross, traffic, order to facilitate the smooth traffic traffic tools of various kinds, the speed gap, in order to avoid each other obstacles, to organize the traffic lane, isolation pier with belt, guardrail or scribing method to separate the public transportation shall set the parking platform, but also set the parking lot for parking set up a bridge or tunnel across the street for pedestrians to cross the busy street, to protect the safety of pedestrians and vehicles to avoid interference in traffic。s City planning and design in the clear road cross section the function, phased implementation, non diversion, there are many problems in protecting the city characteristics, it is difficult to guarantee the sustainable development of city traffic and city city is a pact layout, builtup area population density, per capita construction land index lower than the current level of western developed countries, large In the extreme shortage of land resources in the city, along with the social and economic development level of our country city and city level increases, this situation will further exacerbate the our country, on the one hand, the road construction funds is extremely limited, on the other hand the number of city vehicles are in rapid , how to scientific and reasonable city road cross section the distribution, how to adapt to the traffic demand as much as possible under the premise of improving the efficiency of utilization of land resources, how to improve the efficiency of capital is particularly important in the conditions of limited on road design, improve the urban road of urban road cross section distribution must reflect the different types of traffic on different road, from the road to the branch, pedestrian, bicycle priority should be more and more low, but the car and other vehicles priority should be reflected in a certain priority, improve public transport accessibility, to reflect the different types of traffic flow priority differences, proposed road non machine moving lane, pavement width design need to break the tradition, the width of the planning design with the road The level of the increase is country city underground pipe network layout has not been considered by speaking, the higher the level of the road, pipeline layout required more and more, the road side band width requirements of non motorized vehicle lane is big, so the road cross section design when the width is often determined by the pipeline layout rather than country city greening planning and design specification on all types of road greening rate put forward high requirements, our country city, in addition to the southern part of scenic tourist city, city road greening level does not meet the specification , in order to meet the road layout pipeline and other non transport function and increase the roadside sidewalk Degree can be set for the green belt, to improve the urban landscape, improve the urban road, pleasant atmosphere, reduce the noise of motor vehicle traffic, pollution and other environmental city traffic going through mechanization development, people should draw lessons from the United States in the planning and design of road construction, road transect, must consider the pedestrian friendly, on the street landscape design, focus on the construction of pedestria。s importance in the city road design, the basic functions of attenti