How to calculate the force if the hammer can't drive the pile

2. Drill a small drill and take samples for testing

3. If the pile can not be driven down, it means that the bearing capacity of the pile is enough, but a certain pile depth should be maintained. If it's not safe, add another one nearby.

4. Definitely want to increase the cost of construction units.

5. Hold supervision meeting
analyze the causes
come up with a solution.

6. If it is clayey soil, it will become immovable after a long intermission. For example, in sand layer, on the contrary, the surface seems immovable, but it can be continued after a while. This is e to the stream sliding effect of cohesive soil, which makes the pile easy to be driven down, but as soon as it stops, the cohesive force of the soil begins to work, and it can not be driven for a long time. On the contrary, e to the pressure of water in the sand, the penetration of pile driving is very small, but once the stress of water in the soil dissipates, pile driving is easier. Therefore, the pile with deep clay has high bearing capacity, while the pile passing through sandy soil has low bearing capacity. Therefore, when we pile in the sand area, even if the penetration meets the design requirements, we should continue to drive until the design depth.

7. Hammering is one of the driving methods of precast piles. It is convenient to drive the piles row by row and move the pile frame in one direction. The pile driving efficiency is high. However, the depth of the pile behind will be reced, resulting in uneven settlement, which is suitable for large pile spacing. It is more reasonable to play from the center to the edge and in sections. The function of mud is to fill the space in the soil with seepage to avoid water leakage in the hole. The mud is heavier than water, which also increases the water pressure in the casing, supports the hole wall and prevents hole collapse. In addition, it has the functions of slag carrying, cooling machine and cutting soil lubrication. The forward circulation pore forming equipment is simple, the technology is mature, the slag cleaning ability is weak, the reverse circulation pore forming efficiency is high, and the slag cleaning ability is strong, which is suitable for large diameter deep holes.
the hammer method uses the impact of the pile hammer to overcome the resistance of the soil to the pile, so as to make the pile sink to the predetermined depth or reach the bearing stratum
pile driving equipment includes pile hammer, pile frame and power plant
(1) pile hammer
pile hammer is the main machine to impact the pile and drive the pile into the soil. Pile hammers mainly include drop hammer, steam hammer, diesel hammer
and hydraulic hammer
① drop hammer
the drop hammer is simple in structure, easy to use, and can adjust the drop hammer height at will. Generally, the light drop hammer is driven by hoist. The proction efficiency of drop hammer is low and the pile body is easy to lose. The weight of drop hammer is generally 0.5 ~ 1.5T, and the weight of heavy hammer can reach several tons
② diesel hammer
diesel hammer uses the energy of fuel explosion to push the piston to move back and forth to proce impact to drive pile
the diesel hammer has the advantages of simple structure, convenient use and no external energy supply. But in too soft soil, because of the large penetration, the burning of
oil is not easy to break out, and the hammer often can not jump back, which will interrupt the working cycle. Another disadvantage is that it will cause noise and air
pollution and other public hazards, so the construction in the city is limited. The weight of impact part of diesel hammer is 2.0T, 2.5t, 3.5t, 4.5t, 6.0t and 7.2t. About 40 ~ 80 hammers per minute. It can be used for large concrete pile and steel pipe pile
③ steam hammer
steam hammer uses the power of steam to hammer
according to its working conditions, it can be divided into single acting steam hammer and double acting steam hammer. The impact body of the single acting steam hammer only consumes power when it rises, and falls by its own weight; The lifting of impact body of double acting steam hammer is driven by steam. The steam hammer needs to be equipped with a set of boiler equipment. The impact force of single acting steam hammer is large, and it can drive various piles. The common hammer weight is 3 ~ 10t. The number of hammers per minute was 25-30
times
the shell (cylinder) of the double acting steam hammer is fixed on the pile head, while the hammer moves up and down in the shell. Because of the high impact frequency (100 ~ 200 times / min), the work efficiency is high. The utility model is suitable for driving various piles, and can also be used for driving piles underwater and pulling out piles. The hammer weight is generally 0.6 ~ 6T< (4) hydraulic hammer is a new type of piling equipment, whose impact cylinder is lifted and lowered by hydraulic oil
the lower part of the impact cylinder is filled with nitrogen. When the impact cylinder falls, the first step is to apply pressure to the pile by the impact head, and then to apply pressure to the pile by the compressible nitrogen, so that the process of applying pressure to the pile by the impact cylinder is prolonged, so that greater penetration can be obtained with each blow. Hydraulic hammer does not emit any waste gas, no noise, high impact frequency, and is suitable for underwater piling. It is an ideal impact piling equipment, but the structure is complex and the cost is high
when the pile is driven by hammer, in order to prevent the pile from being damaged e to excessive impact stress, "heavy hammer and light hammer" shall be adopted. If light
hammering is used, a large part of the hammering function is absorbed by the pile body, the pile is not easy to drive, and the pile head is easy to break
(2) pile frame is a pile driving equipment that supports the pile body and hammer, guides the direction of the pile in the process of driving, and ensures that the hammer can impact along the required direction. There are many forms of pile frame. There are two basic forms of common pile frame (which can adapt to a variety of pile hammers): one is the multi-functional pile frame running along the track; the other is the multi-functional pile frame; The other is the pile frame installed on the crawler chassis. ① The multifunctional pile frame is composed of column, diagonal brace, rotary table, chassis and transmission mechanism. It has great mobility and adaptability, and can be used for 360 degrees in the horizontal direction ° Rotary, column can be tilted back and forth, chassis with iron wheel, can walk on the track. This kind of pile frame can be used for all kinds of prefabricated piles and also for cast-in-place pile construction. The disadvantage is that the structure is large, and the site assembly and demolition are troublesome.

8. Generally, the rotary drilling machine is used. In case of large boulder, it is very difficult to drill by hard drilling, so the percussion drilling can only be used. This method has been used normally.