【文章內容簡介】 ore the sediment thickness of not more than 30cm。 when the hole wall is not easy to collapse, not more than 20cm. For the post, in water or shoot the breeze, sediment thickness less than 5cm. Hole cleaning method is to use different and flexible application of drilling rig. Usually you can use normal circulation rotary drilling rig, reverse circulation rotary machine vacuum suction machine and slay pumping cylinder hole cleaning. The mud suction machine hole cleaning, required equipment, convenient operation, hole cleaning is thorough, but unstable in the soil should be used cautiously. Its principle is to use pressor generates high pressure air into a suction dredge pipeline will mud blowing. (7) pouring underwater concrete After finishing hole, can be prefabricated reinforcement cage banging vertically into the hole, positioning to be fixed, and then using a perfusion catheter concrete, pouring concrete don’t interrupt, or prone to the phenomenon of broken pile. Effect of bored pile bearing performance factors In the construction process, construction machinery, due to geological effects, often caused by pile soil ( weak layers ), the thickness of ~, thick and up to 1m. Especially in soft soil with mud, drilling, hole bottom sediment is inevitable。 even after careful cleaning hole, the hole cleaning after and before concrete, will precipitate some sediment, and in drilling process, widespread presence on the hole wall and the hole bottom soil disturbance. All of these affect the bearing capacity of bored pile play. Pile static load test show that, bored pile end bearing capacity of only the ultimate load of the 15%~35%, the side resistance and tip resistance of the existing synchronization phenomenon. Give full play to the role of lateral friction resistance is only a few millimeters of the displacement of pile top, to give full play to the role of tip resistance of pile diameter, needed to reach 10%~30% of the displacement of pile top. Such a large displacement in engineering is not allowed. Pile side friction resistance to damage, and the damage limit is 10 reached, and the end resistance cannot get sufficient play, its potential is great. That is the ultimate bearing capacity of bored pile is not to cause. Research shows that, at the bottom of pile soil exists, not only affects the tip resistance of the play, also make the side friction resistance loss. The existence of weak interlayer of pile, the pile body and the soil friction between the nature of the change, the friction between pile and soil by load transfer, is very bad. This is the bored pile bearing not tall benefit is another reason. the bearing capacity of Bored Piles According to the bearing capacity of bored pile is not to cause analysis, engineering and some improving bearing capacity of pile foundation of the method, mostly around the elimination of pile bottom sediment, a pile of weak interlayer. (1) pre loading method in advance of the pile bottom for preloading, the pile soil paction, improve the bearing capacity of piles. But timeconsuming, costly, and not easy to implement. (2) extending end bearing area. The belled pile, in the past used in engineering is more, but on the bottom of pile soil are still incapable of action. (3) sand lining pile technology : the method for castinplace pile, construction, use double sleeve around the pile in sand filling, bee sand set of about 3~10cm, sand set can improve the lateral wall of the friction resistance of pile. (4) grouting technology : routing technology grouting method can be divided into the first grouting and grouting method. The first method of grouting is drilled in the Kong Zhuangcheng hole and before concrete grouting, the nozzle pipe into the hole bottom is inserted into the soil, spraying slurry, so that at the bottom of pile soil mixed with cement, then pile concrete. cap Cap refers to bear, distribution from pier to carry the load on pile top, set to connect all the top of the pile of reinforced concrete platform. Cap is piles and columns or piers contact part. The root cap, even ten piles are linked with the formation of the pile foundation. Cap for high pile cap generally above the ground or 11 water. High rise pile cap having a free length, the surrounding supporting body to withstand horizontal load. Pile stress situation is extremely unfavorable. Pile internal force and displacement under the action of extremely unfavorable. Pile internal force and displacement under the action of external force than the same level of low pile cap to be big, the stability is poor because of low pile cap. High rise pile cap is generally used for port, wharf, marine engineering and bridge engineering. Low pile cap is generally used in industrial and civil buildings. Pile head generally into platform meters, and a reinforced anchor into the cap. Platform to build on the columns or piers, forming a plete power transmission system. In recent years due to the large diameter bored pile, pile rigidity, strength is big, so high pile in bridge foundation construction has been widely used. 12 全站儀在公路導線和中線測量中的應用 摘 要 介紹全站儀在公路導線和中線測量等方面的應用技巧，提出全站儀使用中應注意的事項。 關鍵詞： 全站儀 ， 公路 ， 測量 ， 技巧 全站儀在導線測量中的應用 （ 1） 全站儀坐標法的優(yōu)點 采用全站儀測點可直接用坐標法，而不需要極坐標法，使儀器操作員從繁重的數(shù)據(jù)計算中解脫出來現(xiàn)在外業(yè)幾乎不用記錄，只是簡單記一下點號和點與點之間的關系，以備內業(yè)整理時參考，也不必配備記錄計算員。內業(yè)整理的時候只要將數(shù)據(jù)從全站儀傳輸至 PC2E500 計算器或直接將數(shù)據(jù)輸入到計算機中，經過坐標平差，在計算機上用 Auto CAD 等軟件繪出點位、取舍點位，求出每一彎道的偏角值、交點間距離以及逐樁坐標等即可。 （ 2） 注意應用國家控 制點及其三維坐標 在用坐標法測點前，盡量找到國家控制點和這些控制點的三維坐標，通過和這些控制點的聯(lián)測，不僅可以檢驗自己的測量精度，而且在誤差允許范圍內可以通過這些坐標進行平差，使測量精確度更高。 （ 3） 點的設置應兼顧放中線的需要 在設點時，不僅應設路線控制導線點，即轉點，也應為放中線做準備，在路線上通視條件好、地勢較高處可以布設一些架儀器的點，這樣做的好處是在放中線是有了更多的選擇機會，不必為增設架儀器點而多次讓儀器轉站。 （ 4） 儀器操作人員配置及后視人員的作用 一般用全站儀配合公路導線測量一共需要 5~6人，其中前視位置 3~4人，儀器操作員 1人，后視 1人。后視人員可讓全站儀記錄更多的點，對后期中線測量和路