本文選題：遼寧沿海灌區(qū) + 抗凍脹　； 參考：《沈陽農(nóng)業(yè)大學(xué)》2017年碩士論文

【摘要】：相關(guān)試驗資料表明,采用渠道防滲措施,水的滲漏損失可減少70%～90%,我國渠道防滲主要采用混凝土渠道防滲。在北方由于氣候等原因,混凝土防滲渠道有凍脹破壞現(xiàn)象,情況較為嚴(yán)重,而遼寧省水田灌區(qū)大部分分布在沿海區(qū)域,因此研究遼寧沿海灌區(qū)渠道的防凍脹破壞,對提高工程耐久性和遼寧省沿海地區(qū)的水稻種植產(chǎn)量并更有效地遏制灌溉用水的浪費現(xiàn)象具有重要意義。首先選取遼寧省內(nèi)距海岸線100km內(nèi)的灌區(qū),對其地下水位、離海岸線距離、設(shè)計灌溉面積三項指標(biāo)進行模糊聚類分析,得到離海岸線距離60km,地下水位在3m以下的灌區(qū)為沿海灌區(qū)。為了研究遼寧省沿海灌區(qū)襯砌渠道的防凍脹,根據(jù)土質(zhì)、地下水位、氣溫相似性,將沿海灌區(qū)劃分為四個片區(qū),其中葫蘆島與錦州為一個片區(qū),丹東與大連為一個片區(qū),營口與盤錦分別為一個區(qū),并選取典型灌區(qū)為海濱灌區(qū)、大洼灌區(qū)、營口灌區(qū)、紅旗水庫灌區(qū)。由于本文中最大切應(yīng)力與凍脹量的計算需要選取與土質(zhì)有關(guān)的參數(shù),所以采集了典型灌區(qū)的土樣,經(jīng)過比重試驗、顆粒分析試驗、界限含水率試驗,對其進行土質(zhì)命名。然后選取遼寧省沿海灌區(qū)襯砌渠道的典型斷面形式:底板寬0.8m,渠深0.8m,邊坡1:1.25,并根據(jù)王正中等建立的梯形混凝土襯砌渠道力學(xué)模型公式,以及抗裂條件公式σ0/Ec≤εt計算可知,采用C25混凝土,襯砌板厚為10cm,可滿足抗裂要求。又根據(jù)遼寧省水利科學(xué)研究所王希堯等人推出的凍脹量公式h=f Zd,和苯板保溫厚度選取的公式δx=αwαλx(R0-δc/λc),得到遼寧省沿海灌區(qū)襯砌渠道適合采用10cm厚的苯板結(jié)構(gòu),可以滿足抗凍脹要求。最后為了驗證以上計算的合理性,以海濱灌區(qū)為項目試點,建立了 12種不同結(jié)構(gòu)形式的襯砌,并實測了 2015年12月至2016年3月期間的渠基土 40cm、80cm的地溫、基土凍深和基土凍脹量3個指標(biāo),通過分析對比發(fā)現(xiàn)當(dāng)斷面形式為底板寬0.8m,渠深0.8m,邊坡1:1.25的襯砌渠道時,可選用C25混凝土,板厚10cm,鋪設(shè)10cm厚苯板結(jié)構(gòu),能夠有效的解決遼寧沿海灌區(qū)的襯砌凍脹問題。
[Abstract]:The relevant experimental data show that the leakage loss of water can be reduced by 70% 90% by adopting canal seepage control measures. In our country, concrete channel is mainly used to prevent seepage. In northern China, due to climate and other reasons, concrete seepage prevention channels have frost heaving damage phenomenon, and the situation is relatively serious. However, most of the paddy field irrigation areas in Liaoning Province are distributed in coastal areas, so the anti-frost heaving damage of the canal in Liaoning coastal irrigation area is studied. It is of great significance to improve the durability of the project and the yield of rice planting in the coastal areas of Liaoning Province and to curb the waste of irrigation water more effectively. Firstly, three indexes of groundwater level, distance from shoreline and designed irrigation area are analyzed by fuzzy cluster analysis. The irrigation area with water level below 3m is the coastal irrigation area, which is 60km from the coastline. In order to study the antifreeze expansion of lining canal in coastal irrigation area of Liaoning Province, according to the similarity of soil quality, groundwater level and temperature, the coastal irrigation area is divided into four regions, one of which is Huludao and Jinzhou, the other is Dandong and Dalian. Yingkou and Panjin are one area, and the typical irrigation areas are seaside irrigation area, Dawa irrigation district, Yingkou irrigation district and Hongqi reservoir irrigation area. Because the calculation of maximum shear stress and frost heave in this paper needs to select the parameters related to soil quality, soil samples from typical irrigation areas are collected and named after specific gravity test, particle analysis test and limit moisture content test. Then the typical section form of lining canal in coastal irrigation area of Liaoning Province is selected: base plate width 0.8m, channel depth 0.8m, slope 1: 1.25. according to the mechanical model formula of trapezoidal concrete lining canal established by Wang Zhengzhong, and the formula of anti-crack condition 蟽 _ 0% EC 鈮，

本文編號：2091758