问题 问答题 简答题

沉管灌注桩在施工时应注意哪些问题?

答案

参考答案:

⑴套管开始沉入土中,应保持位置正确,如有偏斜或倾斜应立即纠正。⑵拔管时应先振后拔,满灌慢拔,边振边拔。在开始拔管时应测得桩靴活瓣确已张开,或钢筋混凝土确已脱离,灌入混凝土已从套管中流出,方可继续拔管。拔管速度宜控制在每分钟1.5m之内,在软土中不宜大于每分钟0.8m。边振边拔以防管内混凝土被吸住上拉而缩颈,每拔起0.5m,宜停拔,再振动片刻,如此反复进行,直至将套管全部拔出。⑶在软土中沉管时,由于排土挤压作用会使周围土体侧移及隆起,有可能挤断邻近已完成但混凝土强度还不高的灌注桩,因此桩距不宜小于3~3.5倍桩径,宜采用间断跳打的施工方法,避免对邻桩挤压过大。⑷由于沉管的挤压作用,在软粘土中或软、硬土层交界处所产生的孔隙水压力较大或侧压力大小不一而易产生混凝土桩缩颈,为避免这种现象可采取扩大桩径的“复打”措施。

改错题
完形填空
Once a man came to a wise man’s house and said, “I have many bad habits. Which one of them should I        first?” The wise man said, “Never tell lies        always speak the truth.” The man        to do so and went home.
At night the man was about to go out to steal. Before setting out, he        for a moment about the promise he made to the wise man. “If he asks me where I have been, what shall I say? Shall I say I went out       ? No, I cannot say that. But nor can I       . If I tell the truth, everyone will start        me and call me a thief. I would be        for stealing.” So the man        not to steal that night, and gave up this        habit.
The next day, he        to drink wine. When he was about to do so, he said to himself. “What shall I say to the wise man        he asks me what I did during the day? I cannot tell a lie.” And so he gave up the        of drinking wine.
In this       , whenever the man thought of doing something bad, he        his promise to tell the truth at all times.       he gave up all his bad habits and became a very        person.
Telling the truth is a very good       . If you always speak the truth, you can save yourself from a lot of        and become a person whom everyone        and admires.
Make a promise: I shall always speak the truth.
小题1:
A.give outB.give offC.give up D.give in
小题2:
A.butB.andC.or D.so
小题3:
A.persuadedB.preferredC.pretended D.promised
小题4:
A.drankB.concerned C.thought D.cared
小题5:
A.stealingB.drinkingC.talking D.walking
小题6:
A.sayB.lieC.help D.move
小题7:
A.catchingB.killingC.believing D.hating
小题8:
A.punishedB.ignoredC.hurt D.expected
小题9:
A.forgotB.decidedC.pretended D.asked
小题10:
A.specialB.unfairC.funnyD.bad
小题11:
A.wantedB.learntC.stopped D.promised
小题12:
A.sinceB.ifC.whether D.before
小题13:
A.wordB.reasonC.adviceD.idea
小题14:
A.houseB.placeC.way D.means
小题15:
A.plannedB.rememberedC.broke D.forgot
小题16:
A.At a timeB.At firstC.At last D.At present
小题17:
A.goodB.richC.calm D.poor
小题18:
A.hopeB.helperC.hobby D.habit
小题19:
A.treasureB.troubleC.pleasure D.wine
小题20:
A.cheatsB.dislikesC.servesD.likes