護(hù)坡樁就是沿基坑邊打的防止邊坡坍塌的樁，通常是在邊坡放坡有效寬度工作面不夠的情況下采用的措施，有了護(hù)坡樁可以防止臨近的原有工程基礎(chǔ)位移、下沉，有了護(hù)坡樁基坑放坡可以使坡比大化。那么護(hù)坡樁的施工工藝是怎樣的？

The slope protection pile is a pile driven along the side of the foundation pit to prevent the slope collapse. It is usually a measure taken when the effective width of the slope grading is not enough. With the slope protection pile, the displacement and settlement of the adjacent original engineering foundation can be prevented. With the slope protection pile, the slope of the foundation pit can be increased. So what is the construction technology of slope protection pile?

采用循環(huán)鉆機(jī)鉆進(jìn)成孔、鋼筋籠現(xiàn)場(chǎng)加工和吊裝、商砼運(yùn)輸至施工現(xiàn)場(chǎng)、導(dǎo)管法灌注工藝進(jìn)行施工,其施工工藝流程見下：

The construction process is as follows:

施工步驟

Construction steps

場(chǎng)地平整→測(cè)量放線→鉆機(jī)就位→校正→鉆進(jìn)成孔→成孔驗(yàn)收→下入鋼筋籠并對(duì)中固定→灌樁砼成樁。

Site leveling → surveying and setting out → drilling rig in place → correction → drilling and hole forming → hole forming acceptance → placing reinforcement cage and centering and fixing → pouring concrete into pile.

成孔

Porogenesis

鉆機(jī)移動(dòng)、就位。

Move and place the drilling rig.

對(duì)點(diǎn)、開鉆，由當(dāng)班技術(shù)員記錄開鉆時(shí)間，監(jiān)理工程師見證。

The technician on duty shall record the spud-in time for the point and spud-in, which shall be witnessed by the supervising engineer.

鉆進(jìn)，鉆進(jìn)前鉆機(jī)操作者調(diào)平鉆機(jī)并使鉆桿自然垂直于地面，當(dāng)班技術(shù)人員使用吊線垂檢查鉆桿的垂直度。

Before drilling, the rig operator shall level the rig and make the drill pipe naturally perpendicular to the ground. The technician on duty shall check the verticality of the drill pipe with a plumb bob.

成孔達(dá)到設(shè)計(jì)深度時(shí)，要進(jìn)行自檢，經(jīng)監(jiān)理工程師驗(yàn)收合格后進(jìn)入下一道工序施工。

When the hole reaches the design depth, self-inspection shall be carried out, and the next process shall be started after the acceptance of the supervising engineer.

鋼筋籠制作及安裝

Fabrication and installation of reinforcement cage

排鋼筋：按鋼筋下料單，將各種規(guī)格的鋼筋排布就緒，電焊機(jī)準(zhǔn)備就緒。

Arrangement of reinforcement: according to the reinforcement blanking list, the reinforcement of various specifications shall be arranged and the electric welding machine shall be ready.

焊接：主筋、加勁筋采用單面電弧搭接焊，螺旋筋采用梅花點(diǎn)焊連接。

Welding: the main reinforcement and stiffener are welded by single-sided arc lap welding, and the spiral reinforcement is connected by plum spot welding.

運(yùn)輸：鋼筋籠采用吊車倒運(yùn)，人力輔助的方式運(yùn)輸。

Transportation: The reinforcement cage is transported by crane and assisted by manpower.

吊裝：鋼筋籠采用吊車安裝就位，鋼筋籠周邊設(shè)船型定位卡，保證混凝土保護(hù)層厚度。

Hoisting: the reinforcement cage shall be installed in place by crane, and a ship-type positioning card shall be set around the reinforcement cage to ensure the thickness of the concrete protective layer.

就位：鋼筋籠就位時(shí)，三點(diǎn)起吊，應(yīng)吊直扶穩(wěn)，對(duì)準(zhǔn)孔位，緩緩放下，不得碰撞孔壁，到達(dá)設(shè)計(jì)樁頂標(biāo)高后將鋼筋籠上緣用吊筋與孔口鋼管固定。

In place: when the reinforcement cage is in place, it shall be lifted at three points, and it shall be lifted straight and stabilized, aligned with the hole position, and lowered slowly. It shall not collide with the hole wall. After reaching the design pile top elevation, the upper edge of the reinforcement cage shall be fixed with the steel pipe at the hole mouth with the hanging bar.

混凝土灌注

Concrete pouring

塌落度測(cè)量，采用高塌落度混凝土（180±20mm），導(dǎo)管法灌注砼成樁。

For slump measurement, high slump concrete (180 ± 20mm) is used, and concrete is poured into piles by tremie method.

試塊制作，混凝土留置試塊，每個(gè)灌注臺(tái)班不得少于1組。

The test blocks shall be made and reserved for concrete. Each pouring machine shift shall not be less than one group.

導(dǎo)管安裝，在樁孔內(nèi)設(shè)置導(dǎo)管時(shí)，導(dǎo)管下端距孔底距離宜為300～500mm，采用Φ225導(dǎo)管，法蘭盤連接，施工前導(dǎo)管應(yīng)試拼、試壓，保證整根導(dǎo)管順直，不漏水、不破裂。

For the installation of tremie, when the tremie is set in the pile hole, the distance between the lower end of the tremie and the hole bottom should be 300~500mm Φ 225 conduit is connected with flange plate. Before construction, the conduit shall be tested for assembly and pressure to ensure that the whole conduit is straight, free from water leakage and crack.

混凝土灌注，灌注混凝土應(yīng)連續(xù)進(jìn)行，不得中斷，并設(shè)專人隨時(shí)測(cè)定孔內(nèi)混凝土面上升高度，記錄混凝土投入量，計(jì)算混凝土充盈系數(shù)。

Concrete pouring shall be carried out continuously without interruption, and a special person shall be assigned to measure the rising height of the concrete surface in the hole at any time, record the concrete input, and calculate the concrete filling coefficient.

由于周圍場(chǎng)地條件或環(huán)境限制，不允許采取放坡法開挖深基坑時(shí)，一般都采用直立邊坡支護(hù)結(jié)構(gòu)的方法。常見的是采用護(hù)坡混凝土灌注樁，沿基坑邊界組成擋墻，以此來支護(hù)基坑邊坡，防止土體塌方。深基坑邊坡采用護(hù)坡樁，不僅減少由于放坡增加的大量土方開挖量，節(jié)省施工場(chǎng)地占用面積，同時(shí)也確保周圍建筑物在施工過程中的使用和安全。更多相關(guān)內(nèi)容就來我們網(wǎng)站http://www.yhyouao.com咨詢吧！

Due to the surrounding site conditions or environmental constraints, when the slope method is not allowed to excavate deep foundation pit, the method of vertical slope support structure is generally adopted. It is common to use slope protection concrete cast-in-place piles to form retaining walls along the foundation pit boundary to support the foundation pit slope and prevent soil collapse. The slope protection pile is adopted for the slope of deep foundation pit, which not only reduces the amount of earthwork excavation increased due to slope grading, saves the area occupied by the construction site, but also ensures the use and safety of surrounding buildings in the construction process. Come to our website for more relevant content http://www.yhyouao.com Ask!