真空預壓施工

真空(kong)預(yu)壓(ya)(ya)(ya)(ya)法(fa)(fa)就是在(zai)需要加固(gu)的(de)軟基(ji)中插入豎(shu)向(xiang)(xiang)排(pai)(pai)水(shui)(shui)(shui)(shui)通(tong)(tong)(tong)道（如砂(sha)井(jing)(jing)、袋裝砂(sha)井(jing)(jing)或(huo)塑料排(pai)(pai)水(shui)(shui)(shui)(shui)板等(deng)），然后在(zai)地面鋪設(she)一層(ceng)(ceng)砂(sha)墊層(ceng)(ceng)，再(zai)在(zai)其(qi)(qi)上(shang)覆蓋一層(ceng)(ceng)不(bu)透氣的(de)薄膜。在(zai)膜下(xia)抽真空(kong)形(xing)成負(fu)壓(ya)(ya)(ya)(ya)（相對大(da)氣壓(ya)(ya)(ya)(ya)而言)），負(fu)壓(ya)(ya)(ya)(ya)沿豎(shu)向(xiang)(xiang)排(pai)(pai)水(shui)(shui)(shui)(shui)通(tong)(tong)(tong)道向(xiang)(xiang)下(xia)傳(chuan)遞 土(tu)體與(yu)豎(shu)向(xiang)(xiang)排(pai)(pai)水(shui)(shui)(shui)(shui)通(tong)(tong)(tong)道的(de)不(bu)等(deng)壓(ya)(ya)(ya)(ya)狀態又使負(fu)壓(ya)(ya)(ya)(ya)向(xiang)(xiang)土(tu)體中傳(chuan)遞，在(zai)負(fu)壓(ya)(ya)(ya)(ya)作用(yong)下(xia)，孔隙水(shui)(shui)(shui)(shui)逐漸滲(shen)流到豎(shu)向(xiang)(xiang)排(pai)(pai)水(shui)(shui)(shui)(shui)通(tong)(tong)(tong)道中而達(da)到土(tu)體排(pai)(pai)水(shui)(shui)(shui)(shui)固(gu)結、強度增長的(de)效果。真空(kong)預(yu)壓(ya)(ya)(ya)(ya)法(fa)(fa)作為新一代(dai)軟基(ji)加固(gu)方法(fa)(fa)，以其(qi)(qi)工(gong)期短、施工(gong)安(an)(an)全、無(wu)污(wu)染(ran)環境(jing)、費用(yong)低等(deng)優點而廣泛應用(yong)于港(gang)口、碼頭(tou)、機場、工(gong)業與(yu)民用(yong)建(jian)筑等(deng)工(gong)程建(jian)設(she)，但理論研(yan)究的(de)落后限(xian)制了其(qi)(qi)工(gong)程上(shang)的(de)進一步推(tui)廣應用(yong)。用(yong)真空(kong)預(yu)壓(ya)(ya)(ya)(ya)加固(gu)軟土(tu)地基(ji)，在(zai)固(gu)結過程中不(bu)僅土(tu)體產生(sheng)垂直(zhi)沉降(jiang)，側向(xiang)(xiang)也(ye)會產生(sheng)向(xiang)(xiang)著負(fu)壓(ya)(ya)(ya)(ya)源的(de)水(shui)(shui)(shui)(shui)平位(wei)移。當在(zai)真空(kong)預(yu)壓(ya)(ya)(ya)(ya)的(de)影響范(fan)圍內(nei)有(you)其(qi)(qi)他(ta)建(jian)筑設(she)施時，使用(yong)該法(fa)(fa)可能會危及其(qi)(qi)上(shang)部(bu)結構(gou)物的(de)安(an)(an)全。真空(kong)預(yu)壓(ya)(ya)(ya)(ya)法(fa)(fa)施工(gong)流程如下(xia)：測(ce)量(liang)放線→鋪設(she)主支(zhi)濾(lv)排(pai)(pai)水(shui)(shui)(shui)(shui)管→鋪設(she)上(shang)層(ceng)(ceng)砂(sha)墊層(ceng)(ceng)→砂(sha)面整平→鋪設(she)聚氯乙烯(xi)薄膜→施工(gong)密封溝→設(she)置測(ce)量(liang)標志→安(an)(an)裝真空(kong)泵→抽真空(kong)預(yu)壓(ya)(ya)(ya)(ya)固(gu)結土(tu)層(ceng)(ceng)。