Rapid consolidation and compaction method for soil improvement of various soil layers and intermediate geomaterial layers in soil deposits

Abstract

The rapid consolidation and compaction method includes: (i) first driving a hollow pipe, (ii) after filling and compacting the sand material in the pipe with a removable end plate, driving the pipe through the hollow pipe to the required depth, generating a high excess pore water pressure of 50 to 300 KPa in the clay soil, (iv) pulling out the pipe section leaving the removable end plate, thereby installing porous drainage piles, which allows the excess pore water pressure to be dissipated horizontally to the porous drainage piles, and the excess water flows vertically from the porous drainage piles to the ground, and (v) the drainage path length is reduced to half the spacing between adjacent porous drainage piles, allowing rapid consolidation to increase density. The installation of porous drainage piles in loose to medium dense sand layers results in an instantaneous increase in their density.

Description

Technical Field

[0001] This application claims a patent for an invention for densifying soil in soil layers and intermediate geotechnical material layers in soil deposits in the technical field of civil engineering and geotechnical engineering. This specification / description is complete in itself. This invention was not funded by federal research or development or sponsored or supported by any other organization. This invention was independently conceived, developed and completed by the inventor Dr. Ramesh Chandra Gupta, Ph.D., PE, President and sole proprietor of SAR6. The inventor Dr. Ramesh Chandra Gupta is a U.S. citizen. Background Art

[0002] The sand well technique (Kennedy and Woods, 1954) for strengthening weak soils has long been widely used. Bowles, 1988 summarized the sand well method for strengthening and consolidating clay soil layers that cannot bear the load of embankments or foundation construction. A circular casing or mandrel is driven vertically into the soft clay layer to the required depth. The soil in the casing or mandrel is removed and the hole is backfilled with clean sand under gravity to form a loose sand column layer around the weak clay soil. The mandrel or casing is then removed by pulling it out of the ground. The embankment is then built in stages on the top of the ground until the full height. If the full height of the embankment is 5 meters, an excess pore pressure of 49 kPa (7.1 psi) will be generated. After allowing sufficient time for consolidation, in order to dissipate the excess pore pressure generated by consolidation, which is usually up to 90%, the embankment is excavated in order to dissipate the excess pore pressure generated by consolidation, whether the embankment is retained in place by the highway or otherwise, and the required buildings, such as houses or airports, oil storage tanks, etc., are built on the original ground or at a certain depth below the original ground. Depending on the horizontal spacing of the sand wells and the coefficient of consolidation of the in-situ clay, consolidation times may vary from 6 months to a year or more. More recently, PVC drains or wick drains have generally replaced sand wells.

[0003] Mars (1978) described another method in which a sounding tube having two partially openable valves in the form of half cones at its ends is driven by a vibrating probe which, with the aid of liquid injection, erodes the in-situ soil around and below the probe to facilitate its penetration to the designed depth. The vibrating probe is very light and has very low centrifugal forces, so pre-drilling or liquid injection is required to erode the soil. The liquid injection tube is an integral part of the sounding tube, which penetrates into the in-situ soil at the end of the sounding tube. The probe has vertical strips at regular intervals around the probe. When the sounding tube is penetrated into the ground, the end valve is kept in the closed position and pebbles, stones, etc. are filled into the sounding tube by gravity through a chute to a very loose density. When the sounding tube is pulled out of the ground, the partially openable valve opens and allows gravel, stone or sand to fall in through its narrow opening, the cross-sectional area of ​​which appears to be less than 25% of the inner area of ​​the sounding tube, thereby forming a column of gravel, stone, etc., the cross-sectional area of ​​which is less than 25% of the inner area of ​​the sounding tube, because before the additional gravel, etc. falls in, the in-situ soil consisting of clay or sand in the remaining outer area of ​​the sounding tube and the strip will fall down quickly and collapse. Therefore, the gravel, etc. that falls in under the action of gravity can only form a column in a very loose state, the cross-sectional area of ​​which is significantly smaller than the inner or outer area of ​​the sounding tube. Loading the embankment in this area to compact it is not described in the method (Mars, 1978). The Mars (1978) method was developed to compact soil areas with low initial bearing strength, such as alluvial or sandy areas or hydraulic fill areas. Many organizations do not allow vibrating probes to be driven into pipes in clay soils. In the sand well technique, embankments are set in the worksite area to reinforce and densify the area, which also results in the densification of the sand wells consisting of loosely packed sand, but the Mars (1978) method does not use embankments that need to be built above the area that has been filled with loose gravel etc. in the vertical holes. Therefore, the Mars method will loosen the area instead of densifying it.

[0004] In this application, the invention comprises a Rapid Consolidation Compaction Method (RCCM) for rapid consolidation of clay soil layers to increase their density and consistency. RCCM comprises: (i) first driving a hollow pipe section to a depth to minimize leveling above the ground or soil layer to be improved, (ii) after filling and compacting the sandy material in the pipe section closed by the removable end plate, driving the soil displacement piles consisting of the pipe section with the removable end plate through the interior of the pre-driven hollow pipe section into the clay layer to the required depth, (iii) as the pipe section with the removable end plate acts as soil displacement piles, the in-situ clay soil is displaced and a high excess pore water pressure is formed, which is expected to be generally in the range of 100 to 800 kPa, but can be as high as 2500 kPa (Note: the value of excess pore water pressure should depend on the consistency and depth of the clay in the ground), (iv) before the pipe section is pulled out of the ground, a weight is placed on top of the compacted material inside the pipe section, (v) the pipe section is now removed or pulled out of the ground; the weight continues to push down the column of compacted sandy material and prevents any necking from forming in the compacted material column , (vi) the removable or separable end plate opens 100% of the interior area and thereby forms a column of compacted sand material having an interior area equal to the interior area, and the weight further applies a downward force which further displaces laterally to occupy a space equal to the exterior area of ​​the pipe section, (vii) therefore, the column of compacted sand material acts as a porous soil displacement pile embedded in the clay soil and allows excess pore water pressure to be generated first and then quickly dissipated, so that the excess pore water first flows horizontally to the porous soil displacement pile and then vertically through the porous soil displacement pile to the ground or the sand layer above or below the porous soil displacement pile, and (v) when the porous soil displacement piles adjacent to the first porous soil displacement pile are installed in a grid shape, the length of the drainage path is further reduced to half the spacing between the adjacent porous soil displacement piles, thereby allowing rapid consolidation of the clay soil layer, resulting in its density and consistency increasing to a level sufficient to support the load of the desired construction (e.g., road surface, civil structure, airport or oil storage tank, etc.). The porous soil piles are installed in a grid shape in a loose to medium dense sand layer, resulting in an instantaneous increase in its density. Therefore, the rapid consolidation compaction method (i.e., RCCM) proposed as an invention in this application improves and increases the density of all types of soil and intermediate geotechnical materials to support the load of engineering construction. Depending on the load support requirements of the building and the underground soil conditions, the sandy material is compacted inside the pipe section to a relative density equal to or greater than 70% or even up to 100%. The maximum value of the excess pore water pressure is at the surface of the cone penetrometer, and the value of the excess pore water pressure decreases rapidly with increasing radial distance from the cone penetrometer. It is expected that the same excess pore water distribution trend will appear around the porous soil piles during the penetration of the porous soil piles. When the length of the flow path is zero or a very short distance from the area with higher excess pore water pressure, the maximum excess pore water pressure near the surface of the porous soil pile will be rapidly dissipated through the porous soil piles.When adjacent porous piles are installed, the length of the flow path will be reduced to half the spacing between adjacent porous piles. For example, if the center-to-center spacing of the porous piles is 4 times the radius of their porous piles, the distance between the surfaces of the porous piles is only 3 times the radius, but from the midpoint between the porous piles is only 1.5 times the radius, which helps to dissipate excess pore water pressure very quickly. In a 30 meter high earth dam, up to 290 kNm is generated in the clay area. 2 The degree of excess pore water pressure requires the sand material to meet the filter criteria to prevent the migration of fine particles of clay soil while allowing free flow of excess pore water pressure. In view of this, the particle size distribution of the compacted sand material in the porous dump pile will also be designed to meet the filter criteria (Prakash and Gupta, 1972).

[0005] In many cases, it may not be practical to pull the pipe section out of the ground. Therefore, porous reinforced concrete piles with or without prestressing, or porous pipe sections with end plates, or pipe sections with small holes and end plates filled with compacted sandy material, should also be installed through the interior of non-displacement piles and used as porous displacement piles if (1) the soil can be driven into it by a pile hammer without exceeding the permissible pile driving stress, (2) free drainage and water flow are allowed and migration of fine particles of clay and silt or fine sand is prevented, and (3) the holes in the pipe or pipe section need to be sufficiently small to retain the sandy material in the pipe section during compaction. These porous displacement piles do not require the pipe section to be pulled out of the ground and installation becomes faster, and there is no noise generated during the extraction of the pipe section.

[0006] In the invention proposed in the present application, it is not necessary to construct an embankment to generate a uniform excess pore water pressure in clay soil, because the penetration of porous dump piles may generate a higher excess pore water pressure. Summary of the invention

[0007] (a) Technical issues of existing geotechnical methods for soil improvement

[0008] As mentioned above, the widely used methods for consolidating and densifying clay or silty soil layers are sand wells or drainage boards (PVC) which have been used for more than 50 years. Other methods such as infiltration are rarely used. Recently, several methods have been proposed that do not increase the consistency or density of clay or silty soil layers, but increase the bearing capacity by installing: (a) Geopiers or (b) stone columns or (c) jet grouting columns or (d) lime or cement mixed columns, in which clay soil is installed in the boreholes by drilling and auger method (Shaefer et al., 2016). Even the bottom feeding stone columns without drilling holes cannot successfully improve the density of clay soil layers, which may be because the extremely strong vibrations of the vibrating probe disturb the clay soil matrix and then cause the clay soil to flow into it. When the holes are excavated using the above methods, a large amount of excavated materials are placed around the engineering site, which must be properly handled to prevent any environmental problems. Reinforced concrete piles or H-piles standing on small footings and several layers of geotextiles separated by sandy materials have been used to support the load of embankments on soft to very soft soils. All of these methods do not increase the density and / or consistency of the soft to very soft soils, but directly support the weight of the embankment without allowing load on the soft clay layer. These methods are very expensive, including millions of dollars per mile (1 mile = 1.6 kilometers). There is no historical case history for the above newer technologies, which can indicate their successful long-term behavior.

[0009] For compacting the sandy material layers in soil deposits, there are several methods being used, such as dynamic deep compaction by dropping weights from a selected height, vibro displacement and vibro-displacement, geopiers using tamped gravel material, bottom-fed or top-fed stone columns, etc. The vibro-displacement or stone column equipment has a frequency of 3000 rpm, a centrifugal force of 30,000 kg, a weight of 9,000 kg, a height of about 2.5 meters, and an inner diameter of about 38 cm. The vibro-displacement and stone column vibration equipment has a central hole through which a water jet is ejected to erode the soil when the subsoil conditions are such that vibration alone cannot penetrate further into the soil or when the penetration rate becomes too slow. Rapid consolidation compaction using porous spoil piles is a new method that can successfully densify sandy materials without generating excess pore water pressure in the sandy material or, if it does, dissipates rapidly once generated. RCCM generally requires readily available instruments and machinery, such as cranes and pile hammers, extractors, flat or plate vibrators, etc., which can be rented or leased in most places or sold by the manufacturer.

[0010] (b) Problem-solving and beneficial effects of the present invention

[0011] As described above, the rapid consolidation and compaction method is provided to increase the density of sandy and clayey materials. Since sandy materials are very economical due to their very low cost compared to jet grouting columns, Geopier or cement columns or lime columns mixed with clayey materials, the cost of using the rapid consolidation and compaction method is much lower and can save millions of dollars on large projects. Depending on the selected spacing between adjacent porous piles and the relative density of the compacted sandy soil in the porous piles, the rapid consolidation and compaction method (i) densifies very soft to soft clayey soil into hard or very hard clayey soil, (ii) densifies medium hard clayey soil into hard or very hard clayey soil, (iii) densifies hard clayey soil into very hard clayey soil, and (iv) densifies very hard clayey soil into firm or very firm clayey soil. Similarly, depending on the selected spacing between adjacent porous soil removal piles and the relative density of the compacted sandy soil in the porous soil removal piles, the rapid consolidation compaction method (i) compacts very loose (relative density less than 15%) sandy soil into medium dense (relative density of 35% to 65%) sandy soil, (ii) compacts loose (relative density of 15% to 35%) sandy soil into medium dense or dense (relative density of 65% to 85%) sandy soil, (iii) compacts medium dense sandy soil into dense sandy soil, and (iv) compacts dense sandy soil into very dense (relative density greater than 85%) sandy soil. For the compacted sandy material in the soil removal pipe section with removable end plates (which is pulled out of the ground after installation to form the porous soil removal piles), when it is necessary to densify the in-situ soil to a higher density, the relative density of the sandy material in the porous soil removal piles can be selected to be more than 70% or even up to 100%. Both the layered densified in-situ clayey silt and in-situ sandy soil to the selected depth below the ground should be able to provide support for the building foundations with adequate bearing capacity and minimal settlement. During the construction of the building on the densified in-situ soil, any excess pore water pressure, if generated, will dissipate quickly and small settlement will occur before the building reaches its full height. When RCCM is selected, there is no need for embankments required for sand wells or PVC drain pipes and waiting for consolidation for 6 months to more than a year. Therefore, construction progress can become very rapid, which is very important for highway projects used to expand or widen existing roads and highways or for supporting various building foundations. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1A : Typical details showing installed non-displacement piles (120) and pipe sections (123) with removable or detachable end plates (124) and filled with compacted sand material.

[0013] Figure 1B : Typical details of a pipe section (123) driven to the designed depth with a removable or separable end plate (124).

[0014] Figure 1C: Typical detail showing a hammer or weight (126) placed on top of compacted sandy material (125) before pulling a pipe section (123) out of the ground.

[0015] Figure 2A : Typical detail of a column of compacted sand material used as a porous spoil pile (125) and a hammer or weight (126) remaining on the porous spoil pile (125) after the pipe section is pulled out of the ground.

[0016] Figure 2B : Typical detail of the porous spoil piles (125) below the installed end plate (124).

[0017] Figure 3A : Typical details of an arrangement for providing lateral support to a pipe section (123) during compaction of sandy material in the pipe section (123).

[0018] Figure 3B : Another typical detail of an arrangement for providing lateral support to a pipe section (123) during compression of sandy material in the pipe section (123).

[0019] Figure 4A : Typical detail of an articulated connection connecting a pipe section (123) to a removable and separable end plate (124).

[0020] Figure 4B : Typical detail showing the end plate becoming vertical during extraction of a pipe section (123) from the ground.

[0021] Figure 5A : Typical detail of a pipe segment (123) having a removable and detachable short tube (132) inserted inside the pipe segment (123), wherein the short tube (132) is attached to an end plate (124).

[0022] Figure 5B : Showing typical details of the removable and detachable spool piece (132) and end plate (124) left behind when the pipe section (123) is pulled out of the ground.

[0023] Figure 5C : Typical detail showing the removable end plate (124) attached to the connecting rod (133); the connecting rod (133) is fastened to the top of the pipe section (123) by bolts (13%).

[0024] Figure 5D : Shows typical detail of the tie rod (133) and removable end plate (124) left after the bolts (135) are removed during extraction of the pipe section (123) from the ground.

[0025] Fig. 6A: A typical detail of a removable end plate (124) connected to a pipe section (123) by means of a hinge (130) on one side and by means of an angle profile (137) also bolted to the pipe section (123) on the opposite side, for hoisting a pipe section (123) filled with compacted sand material to the position where it is to be driven into the ground.

[0026] Figure 6B : Typical detail of a pipe section (123) bolted to a short pipe section (132) attached to an end plate (124) for hoisting a pipe section filled with compacted sand material to the location where it is to be driven into the ground.

[0027] Fig. 7A : A typical plan view showing the grid lines (151) and locations (150) of porous spoil piles used for soil improvement beneath an extended footing.

[0028] Figure 7B : An elevation view showing the porous spoil piles (125) installed below the spread footing.

[0029] Fig. 8A : Typical details of porous spoil piles (125) installed beneath an embankment.

[0030] Figure 8B : Typical details of porous soil piles installed below an embankment, wherein the porous soil piles at a first position are installed in front of the embankment, and the embankment extends over the installed porous soil piles (125).

[0031] Fig. 9 : A typical plan view showing the grid lines (151) and locations (150) of porous spoil piles used for soil improvement beneath and near the foundations of the Leaning Tower of Pisa.

[0032] Fig.10 : Typical details showing the foundation and subsoil layers of the Leaning Tower of Pisa and the inclined porous spoil piles (125). DETAILED DESCRIPTION

[0033] The main motivation of the Rapid Consolidation Compaction Method (RCCM) of the present invention is to develop a method of soil improvement which can densify the soil layer or intermediate geomaterial (IGM) layer in soil deposits. Cohesionless soil is defined as N 60 Less than 50blows / 0.3m, and non-adhesive IGM Category 3 is defined as N 60 Greater than 50 blows / 0.3m (AASHTO, 2012). Cohesive soil is defined as having an undrained shear strength less than 0.25MN / m 2 , while cohesive IGM Category 1 is defined as an undrained shear strength greater than 0.25 MN / m2(AASHTO, 2012). The invention of the present application includes a rapid consolidation compaction method (RCCM) for forming a rapid consolidation of a clay layer to increase its density and consistency. The RCCM includes (i) first driving a hollow pipe section to a certain depth to minimize the leveling above the ground or soil layer to be improved, (ii) after filling and compacting the sand material in the pipe section closed by a removable end plate, driving a drainage pile consisting of a pipe section with a removable or separable end plate through the interior of the pre-driven hollow pipe section into the clay layer to the desired depth (iii) As the pipe section with a removable end plate acts as a drainage pile, the in-situ clay soil is displaced and a high excess pore water pressure is formed, which is expected to be generally in the range of 100 kPa to 800 kPa, but can be as high as 2500 kPa (Note: The excess pore water pressure value depends on the consistency and depth of the underground clay). Cooper Marl recorded pore water pressures ranging from 260 psi (1793 kPa) to 400 psi (2758 kPa). Peuchen et al. (2010) recorded pore water pressures ranging from 50 kPa (7.25 psi) to 800 kPa (261 psi) during penetration tests in heavily overconsolidated clay soils, (iv) a weight is placed on top of the compacted material inside the pipe section before the section is pulled from the ground, (v) as the section is removed or pulled from the ground, the weight continues to push down on the column of compacted sand material and prevents any necking from forming in the column of compacted material, (vi) the removable or detachable end plate opens 100% of the interior area and thereby forms a column of compacted sand material equal to the interior area, and the weight further applies a downward force which further displaces the compacted sand soil laterally to account for (vii) therefore, the compacted sand material column acts as a porous soil pile embedded in the clay soil and allows excess pore water pressure to be generated first and then quickly dissipated, so that the excess pore water first flows horizontally to the porous soil pile and then flows vertically from the porous soil pile to the ground or the sand layer above or below the porous soil pile, and (v) when the porous soil piles adjacent to the first porous soil pile are installed in a grid shape, the length of the drainage path is further reduced to half the spacing between adjacent porous soil piles, thereby allowing rapid consolidation of the clay soil layer, resulting in an increase in its density and consistency sufficient to support the load of the required construction (such as a road surface, civil structure, airport or oil storage tank, etc.). In the loose to dense sand layer, the installation of porous soil piles in a grid shape causes its density to increase instantly. Therefore, the Rapid Consolidation Compaction Method (i.e., RCCM) proposed as an invention in this application improves and increases the density of all types of soils and intermediate geotechnical materials (whether loose or dense, soft or very hard) to support the loads of engineering construction. The sandy material inside the pipe section is compacted to a relative density equal to or greater than 70% or even up to 100%, depending on the load support requirements of the construction and the underground soil conditions.When building footings on soils compacted by RCCM, the weight of the building further creates super-pore water, which also consolidates rapidly, and the footings may continue to settle evenly with very small amplitudes as the substructure and superstructure are constructed, but after the superstructure is completed there will be almost no settlement, if any, which will occur evenly. After the installation of the porous spoil piles is completed, the topsoil may be compacted by the general contractor using a compaction roller or sheepsfoot roller, etc., if required in accordance with the engineering drawings.

[0034] For the above process, the hollow pipe section (120) is driven into the soil to a selected depth (121) to reduce the leveling of the ground. The hollow pipe section has a very small annular area compared to its outer or inner area, so for geotechnical purposes, the hollow pipe pile is called a non-displacement pile. Similarly, a pile consisting of an HP section and a channel section, etc. is called a non-displacement pile. Figure 1A and Figure 1B As shown, after the non-displacement pile (120) is driven into the ground, the displacement pile consisting of a pipe section (123) with a removable end plate (124) and filled with compacted sand material (125) is driven into the layer to be densified. Since the end plate is attached to the bottom of the pipe section, when driven into the ground, the pipe section with a closed end displaces the in-situ soil, thereby reducing the void volume of the in-situ soil, or generates excess pore water pressure and occupies its space; thereby eventually densifying it. Figure 1C A weight or hammer (126) is placed on top of the sandy material and the pipe section is then pulled out of the ground, leaving a removable or detachable end plate at the bottom of the compacted sand column, as shown. Figure 2A As shown. The weight or hammer (126) helps to continue pushing down the sandy soil column and even helps to push the sand in the column laterally to occupy the space left by the thickness of the pipe section. During the extraction of the pipe section from the ground, as an option, several drops of the weight after lifting a few centimeters can further help to displace the sandy material into the void formed by the extracted pipe section (123). Thereafter, the non-drainage pile (122) is also extracted and several drops of the weight or hammer further help to displace and compact the sandy material (125) into the void formed by the extracted non-drainage pile (120). In this way, as Figure 2B As shown, porous spoil piles (125) composed of compacted sand material are installed at the depth of the ground where compaction or soil improvement is required.

[0035] The hollow pipe or pipe segment can be circular, square or rectangular or any shape available or made in the industry. Sometimes, two angle profiles or two channel parts welded together can also be used as hollow pipe segments. When these segments are attached with detachable or removable end plates and used as drainage piles to be driven into the ground, it is called drainage pile for geotechnical purposes because it displaces the soil by occupying the soil position. When these segments (i.e., hollow segments) without any end plates at their bottom are driven into the ground, it is called non-drainage piles for geotechnical purposes. If the land below it is dense enough to limit settlement so that the end plate is intact at the bottom of the drainage pile, the sandy material can be compacted at the position where the pipe segment is to be driven or in the ground instead of the position where the pipe segment is driven or other positions of the pipe segment after being driven into the ground.

[0036] The non-discharge piles are driven into the ground first so as to minimize the leveling of the ground or the top of the layer to be densified. Ideally, there should not be any leveling of the ground during the driving of the discharge piles, so as to achieve the maximum lateral displacement of the soil by the porous discharge piles, thereby achieving maximum densification. This is why, in order to minimize leveling, the non-discharge piles are first driven to a selected depth and then the discharge piles are driven through the non-discharge piles. If the step of driving the discharge piles through the non-discharge piles is omitted due to economy or any other reasons (such as being impractical at a particular location, etc.) and the discharge piles are driven directly, or when the non-discharge piles are not driven to a depth sufficient to minimize or prevent leveling, although the in-situ soil will not be completely densified due to some leveling of the ground, it can be considered satisfactory in some cases. In this case, the amount of densification is small because the volume of the in-situ soil displaced by the discharge piles will be the sum of the reduction in the voids in the in-situ soil plus the volume of the soil leveled on the top of the ground or the layer to be densified. When the weight of the covering soil above the bottom of the non-drainage pile (120) is sufficient to prevent the ground from leveling, the covering soil above the depth of the bottom of the non-drainage pile (120) plays a role in preventing the ground from leveling or minimizing the ground from leveling to a reasonable range. According to existing research, depending on soil conditions, a covering depth of 7 to 10 times or more may be sufficient to limit the ground from leveling. However, there is currently no sufficient or substantial research available to predict the reasonable depth in different types of soils of different densities or consistencies to prevent or minimize the ground from leveling when the drainage pile is driven into the ground (121). When implementing a project that includes the use of RCCM for foundation treatment, sufficient research should be conducted to predict the reasonable depth in different types of soils of different densities or consistencies (121).

[0037] The sandy soil (125) is filled in the pipe section (123) in layers and each layer is compacted by a specific number of drops of a hammer or weight (118) to achieve a specific dry density or relative density. A connecting pipe or connecting rod (127) connects the weight or hammer to the crane boom or pile hammer system ( Figure 1C Alternatively, the sandy soil may be filled in layers, and then a hammer or weight (118) may be placed on top of each layer, followed by vibrating by attaching a flat vibrator to the side of the pipe section (123), or by placing a vibrating probe / weight on top of each layer to compact the sandy soil to a specified dry density or relative density. The pipe section (123) with a detachable or removable end plate is typically kept vertical while the sandy material is filled and compacted therein.

[0038] Preferably, the density of the compacted sand material inside the pipe section (123) is generally based on a relative density of about 70%, as this is the requirement usually followed for compacting embankments. When it is necessary to compact hard to very hard clay into firm clay or to compact medium dense or dense sand into very dense sand, the relative density of the compacted sand material in the pipe section may be about 70% or more, and even up to 100% may be more appropriate. In seismic zones and on faults, or under nuclear power plants, even very hard clay or dense sand may require further compaction, in which case a relative density of more than 70% to even up to 100% may be specified for the compacted sand soil column used as porous spoil piles. However, when extremely soft clay or soft clay is compacted into medium-hard clay or loose or extremely loose sand is compacted into medium-dense sand, if the construction support requirement of the construction site can be met by porous soil removal piles containing compacted sandy materials with relatively low relative density, the relative density requirement can be relaxed. The relative density of medium-dense sand varies from 35% to 65%. If it is necessary to compact its underground layer to a relative density equivalent to the medium-dense sand state to meet the construction foundation support or overall ground support of the construction site, it is sufficient to set the porous soil removal piles composed of sandy material columns to the relative density required for medium-dense sand, so in this case, it is necessary to compact the sandy soil in the pipe section (123) to reach a medium-dense state. Therefore, according to the requirements of the engineering site, it is necessary to compact the sandy soil in the pipe section (123) to reach a medium-dense or dense or extremely dense state. Selection of appropriate porous spoil pile spacing and diameter is also important in determining the extent to which the porous spoil piles are displaced and compact the in-situ soil to densify it. To densify the sandy soil in the pipe section (123) to a greater relative density, only a few additional hammer drops are required on each layer of sandy soil in the pipe section (123), which is considerably easier, less time consuming, and requires only little additional cost. Porous spoil piles having a relative density greater than that of the densified in-situ soil densified by the rapid consolidation compaction method should act as reinforcement to share more of the load of the embankment or building foundation than that shared by the densified in-situ soil, thereby reducing the total settlement of the building and embankment. All of these technical points should be considered in the design of porous spoil piles for each project.

[0039] Figure 3AA typical example of a support system is shown which maintains the pipe section (123) in a vertical position during compaction of the sandy soil in the section, whereby it is desirable that the pipe section be laterally supported by horizontal cross braces (111). The horizontal cross braces are attached to the vertical column section (110) on either side. The column section is supported on a concrete pad or slab and fastened therein with nails or bolts (114). Alternatively, as Figure 3B The pipe section (123) shown is held vertically by sliding it into another pipe section (116) which has been driven into the ground to a sufficient depth to maintain lateral stability; this pipe section (116) also protrudes above the ground to maintain the vertical and lateral stability of the pipe section (123) when compacting the sandy material in the pipe section (123). Each project should be specifically designed for the lateral support system based on the length and size of the pipe section and the soil conditions, and these typical examples should also be considered at this time. When the submerged soil in a river or ocean is to be densified from a vessel or floating platform or large ship, the lateral support system should be discussed with the owner and specifically designed.

[0040] Various types of hammers / weights may be used to drop on the sandy soil placed inside the pipe section (123) to densify the sandy soil; any of these hammers / weights and their accessories may be used as deemed appropriate according to the equipment manufacturer's instructions or manuals. Various types of planar vibrators are available in the industry and may be used around the pipe to densify the sandy soil inside the pipe section (123) when weights or hammers have been placed on top of the sandy material to compact the sandy material, or vibrators are placed on top of plates or vibrating weights to densify the sandy soil inside the pipe; any available system may be used as deemed appropriate according to the manufacturer's manuals or instructions. There are many types of pile hammers, including industrially available vibrating pile drivers for driving non-discharge piles or discharge piles; any of these pile hammers may be used as deemed appropriate. There are various types of pile pipe pullers available in the industry, including vibrating pullers or pullers with hydraulically operated claws to grasp the pile, for pulling non-discharge piles or discharge piles out of the ground; any of these pullers may be used as deemed appropriate. The attachment between the pipe section or rod (127) and the crane by U-bolts or hooks etc. or the attachment between the puller and the pipe section (123) or the attachment between the flat vibrator and the pipe section (123) or vibrating plate etc. shall comply with the manufacturer's instructions and manual. When driving pipe sections, all accessories of the pile hammer shall comply with the pile driving specifications. Many organizations do not allow vibratory pile drivers to drive non-displacement piles or displacement piles in clayey silts because it is believed that the vibration reshapes and disturbs the matrix and lock-in-stresse of the clayey silt.

[0041] Figure 4A , Figure 4B , Figure 5A , Figure 5B , Figure 5C , Figure 5D , Fig. 6A and Figure 6B Several typical examples of detachable or removable end plates are shown in FIG. Figure 4A The detachable end plate is shown, which is attached to the hinged connection (130) at one end of the pipe section (123) by bolts (131); during the driving of the pipe section (123), the detachable end plate (124) remains attached to the bottom, but when the pipe section (123) is pulled out of the ground, as shown in FIG. Figure 4B As shown, the removable end plates (124) connected by hinges (130) become vertical, thereby assisting in pulling the pipe section (123) out of the ground while keeping the compacted sand material in place. Figure 5A A short pipe section or corrugated tube section (132) is shown located inside the pipe section (123) but attached to the end plate (124). During steady and careful driving, the short pipe section (132) and the end plate remain in place at the bottom of the pipe section (123), but when the pipe section (123) is pulled out of the ground, the end plate (124) attached to the short pipe or corrugated tube section (132) remains in the ground, as shown in FIG. Figure 5B As an additional option, the pipe segment (132) may also be attached to the pipe segment (123) by thin aluminum rivets, but these rivets may break when the weight of the compacted sand material exerts its weight to break the aluminum rivets. Figure 5C An end plate (124) is shown attached to a plurality of tie rods (133) mounted vertically upwardly on the exterior of the pipe segment (123) at diametrically opposed locations and secured by bolts (135) near the top of the pipe segment (123). The tie rods (133) pass through a circular plate (136) supported by a plurality of angle profiles (140) and secured by bolts (135) near the top of the pipe segment (123). The end plate (124) remains attached during driving of the spoil pile, but prior to extraction of the pipe segment (123), the bolts (135) are removed and the removable end plate (124) is left in the ground when the pipe segment (123) is extracted from the ground, as shown. Figure 5D In this way, the compacted sandy material is retained in place to form a porous spoil pile. In each project, the removable or separable end plates can be specially designed according to the soil conditions and the length and size of the spoil pile, and the above typical examples should also be considered.

[0042] The above details are applicable when compacting the sandy material in situ at the location where the pipe section (123) is driven. When the sandy material in the pipe section (123) is compacted at some other location and then transported to the selected location where it is to be driven into the ground, an additional attachment to the end plate (124) is necessary. In this case, Figure 5A and Figure 5B The detachable plate arrangement is still valid, but Figure 4A , Figure 4B , Figure 5A and Figure 5B Some improvements are needed. Fig. 6A As shown, a plurality of angle profiles (137) are attached by bolts to the pipe section (123) on diametrically opposite sides to each other and are also attached to the hinge connection (130). Figure 6B The short pipe sections (132) are shown attached to opposite sides of the pipe section (123) on the diameter thereof by a plurality of bolts. When the pipe section (123) is transported to the selected driving position, the bolts (138) must be removed and the angle profile (137) slid out. Similarly, when the end plate contacts the ground, the bolts (138) must be removed. Figure 6B The bolts (131) shown are then released and the crane slings are then released to lower the spoil pile above ground.

[0043] In order to successfully extract the pipe section (123) from the ground, the weight of the weight or hammer (126) maintained on top of the compacted sand material is designed based on the side friction resistance generated between the compacted sand material inside the pipe section (123) and the side friction resistance generated between the outside of the pipe section (123) and the in-situ soil surrounding it, as well as any suction exerted on the end plate by the in-situ soil during extraction of the pipe section. Similarly, the weight of the weight or hammer and the number and height of drops are designed to achieve a specified density. Although the structural members of non-discharge and drainage piles are described as being composed of circular sections as shown in the text and drawings, any unconventional sections of hollow rectangular or elliptical sections or any other unconventional sections can be used for RCCM and can be used according to customer needs. During the driving of non-discharge or drainage piles, it is sometimes important to limit noise and vibration, in which case it may become important to have a heavy hammer with a very small height drop or to hydraulically drive the pile into the ground in order to minimize or limit damage or risk to adjacent structures. To monitor settlement of adjacent structures, settlement readings may also be taken at the structure and ground level and at a depth below ground. In addition, it may be desirable to perform a wave equation analysis (Pile Dynamics, Inc., 2005) of the driven pipe section (123) using the selected hammer. In order to determine the amount of improvement and density increase of the improved in-situ soil, in-situ testing methods may also be used to perform underground detection and laboratory testing of samples extracted from the in-situ soil before and after the installation of the porous spoil piles.

[0044] In addition to densifying and improving the soil around it, the porous spoil piles consisting of compacted sand material columns have another important function, which is to prevent clay or silty particles from entering or migrating into the compacted sand material while allowing water to flow freely through the compacted sand material column to dissipate excess pore water pressure. The gradation of compacted sand material that performs the function of a filter to restrict the migration of fine materials and allow free flow of water should be designed based on the design standards for filters or filter tubes used in earth dams or earth-rock dams, using Terzaghi's standards (Prakash and Gupta, 1972) with or without some modifications made by different organizations (such as the US Bureau of Reclamation, etc.). The sand material can be composed of a mixture of sand and a small amount of small gravel, but it should meet the requirements of allowing free flow of water and preventing fine particles of the in-situ soil from migrating into the compacted sand material column. The sand material should not contain more than the specified amount of fine particles in order to maintain the free flow of water. Typically, well-graded clean sand is used in sand wells; the same type of material can be used for porous spoil piles when it meets filter standards.

[0045] In brief, Terzaghi's criteria can be described as follows:

[0046] (1) Standards for pipeline transportation or migration of particles: D 85(基础) Indicates the particle size that must be retained. D 15(过滤器) Represents the average pore size. The filter captures particles larger than about 0.1D 15(过滤器)

[0047] D 15(过滤器) <4 to 5D 85(基础)

[0048] Permeability or Free Flow Criteria:

[0049] D 15(过滤器) >4 to 5D 85(基础)

[0050] Grading control

[0051] D 50(过滤器) <25D 50(基础)

[0052] The sand material in the porous spoil piles acts as a filter. The in-situ clayey silt surrounding the compacted sand material of the porous spoil piles is used as the foundation in the above standards. 15 is 15% finer by weight of material, diameter, D 85is the particle size of 85% of the material by weight being finer. In geotechnical engineering, the concern of the engineer is usually to make the best use of the available soil near the site. If for any reason the sandy soil near the engineering site is slightly beyond the requirements of the conservative Terzaghi's standard, then laboratory tests such as those described in Prakash and Gupta, 1972 or in publications of the U.S. Bureau of Reclamation or other publications can be performed to check whether the sandy soil on site meets the filtration characteristics of the filter tube.

[0053] During pore pressure penetration testing in highly stratified and overconsolidated soft to hard soils, the cone tip penetration resistance (q c ) from 0.1 to 1 MPa, and the seepage pore water pressure ranges from 50 to 1.8 MPa (7.25 to 261 psi), with values ​​recorded increasing with depth below ground from the surface to depths of about 22 meters (Peuchen, 2010). Seepage pore water pressures of this magnitude are to be expected during the penetration of piles into cohesive soils. A seepage pore water pressure of 1.8 MPa is equivalent to a 183.6 meter head of water in a 183 meter (600 foot) high earth / concrete dam reservoir. Therefore, the compacted sandy soil of the porous piles can withstand such high pore water pressures and should meet the filter pipe standards for earth and rockfill dams. In this case, if an approximately 1" (25 mm) pipe with a porous plate at its bottom is driven into the porous pile, clear water can be seen flowing out of the top of the pipe.

[0054] Porous soil displacement piles comprising compacted sandy soil columns have been described above. Another equally attractive method is to install porous soil displacement piles to perform the same type of function, but which is more expensive than the methods already described. If (1) the soil can be driven into it by a pile hammer without exceeding the permissible pile driving stress, (2) free drainage and water flow are allowed and fine soil particles or fine sand of clay and silt are prevented from migrating into the porous soil displacement piles, and (3) the holes in the pipe or pipe section need to be relatively small to retain the sandy material during compaction of the pipe section, then porous prestressed reinforced concrete piles (or even without prestressing), or porous pipe sections with end plates, or pipe sections with small holes and end plates filled with compacted sandy material, can also be installed through the interior of non-soil displacement piles and used as porous soil displacement piles. These porous soil displacement piles do not require the pipe section to be pulled out of the ground, and installation will also be easier and faster. In many cases, where the soil layer consists of very sticky clay, or when inclined piles are involved, or when any more vibrations or noise cannot be tolerated, extracting the pipe section may be difficult or may not be permitted by the authorities.

[0055] In many areas, such as seismic zones, local building codes may not allow construction unless the relative density is above a certain value. Table 1 gives the relationship between earthquake magnitude and relative density for a groundwater level of 1.5 meters below the surface:

[0056] Table 1: Approximate relationship between earthquake magnitude, relative density (Dr) and liquefaction potential at a water table 1.5 m below the surface (from Seed and Idriss, 1971)

[0057] seismic acceleration High probability of liquefaction The likelihood of liquefaction depends on soil type and earthquake acceleration. Low liquefaction probability 0.10g <![CDATA[D r <33%]]> <![CDATA[33%<D r <54%]]> <![CDATA[D r >54%]]> 0.15g <![CDATA[D r <48%]]> <![CDATA[48%<D r <73%]]> <![CDATA[D r >73%]]> 0.20g <![CDATA[D r <60%]]> <![CDATA[60%<D r <85%]]> <![CDATA[D r >85%]]> 0.25g <![CDATA[D r <70%]]> <![CDATA[70%<D r <92%]]> <![CDATA[D r >92%]]>

[0058] In this case, RCCM is used to densify the subsoil in the 0.10g zone area to D as required. r If the relative density of the sandy soil in the pipe section is greater than 55%, it may be necessary to compact the relative density of the sandy soil in the pipe section to at least 55% or more. In the 0.15g zone area, RCCM is used to compact the underground soil layer to D r If the relative density of the sandy soil in the pipe section is greater than 75%, it may be necessary to compact the relative density of the sandy soil in the pipe section to at least 75% or more. In the 0.20g zone area, RCCM is used to compact the underground soil layer to D r If the relative density of the sandy soil in the pipe section is greater than 85%, it may be necessary to compact the relative density of the sandy soil in the pipe section to at least 85% or more to keep these areas at a low probability of liquefaction. In the 0.20g zone area, RCCM is used to compact the underground soil layer to D r If the relative density of sandy soil in the pipe section is greater than 85%, it may be necessary to compact the relative density of sandy soil in the pipe section to at least 85% or more to keep these areas at a low probability of liquefaction. In the 0.25g zone area, RCCM is used to compact the subsoil layer to 95% or greater D r , then the relative density of the sandy soil in the pipe section may need to be compacted to at least 95% or more to place these areas at a low probability of liquefaction. The spacing and diameter of the porous soil piles need to be designed to achieve the displacement of the in-situ soil and the reduction of the void volume to achieve the required densification and density of the underground layer at the site. From the above discussion, it can be seen that the requirements for compacting the sandy soil in the pipe section (123) to a specific relative density and the spacing and diameter of the porous soil piles depend on the underground soil conditions at a certain location and the required degree of densification of the underground layer at that location.

[0059] Typical examples of industrial applications of RCCM

[0060] Ground treatment beneath the extended footing

[0061] RCCM can provide an economical and very useful solution when the project requires ground improvement of the soil layer. For example, the extended footings of a bridge foundation will be built on soil consisting of a weak soil layer (140) and soil improvement is required to support the loads from the bridge superstructure. Fig. 7AA typical arrangement of grid lines (151) and center positions of porous soil piles (150) composed of compacted sand material (125) columns is shown in a square or rectangular grid pattern. The position marked by the number "1" at the grid intersection (150) is the first position where the porous soil pile is first installed using the method described in the above paragraph. The position marked by the number "2" at the grid intersection is the second position where the porous soil pile is installed after the installation at the first position is completed. The second position is usually selected at the center of the grid of the four first positions. The position marked by the number "3" at the grid intersection is the third position where the porous soil pile is installed after the installation at the second position is completed. The position marked by the number "4" at the grid intersection is the last and final position where the porous soil pile is installed after the installation at the third position is completed. Similar arrangements of the positions of the porous soil piles can also form a triangular pattern or a quadrilateral pattern, as is done for vibrodisplacement columns, or any other selected grid pattern selected for a specific configuration at the engineering site.

[0062] Figure 7B Show Fig. 7A Elevation view of the grid pattern shown. Figure 7B In the embodiment, a reinforced concrete foundation (146) has been laid on an anti-sinking plate (147). Porous drainage piles consisting of compacted sandy material are installed to a designed depth in the layer, in this case, in the soil layer (141). Example 1: Assume that the top layer (142) and the bottom layer (141) are composed of sandy material, and the interlayer (140) is composed of soft clay. In this case, if the layer (142) is thick enough to minimize the leveling of the top of the weak layer (140), the pipe section with a detachable end plate can be driven from the ground without first driving the non-drainage piles, otherwise it is advisable to first drive the non-drainage piles and then drive the pipe section (123) with a detachable end plate (124) through the inside of the non-drainage piles. Example 2: Assume that the top layer (142) is composed of clay, and the interlayer (140) is composed of loose sand and needs to be compacted. In this case, it is advisable to first drive the non-displacement piles into the bottom of the top layer (142) or into a small depth in the loose sand layer (140). It is advisable to drill out the clay soil from inside the non-displacement piles and drive the pipe section (123) with a detachable end plate (124) into the designed depth. This will avoid pushing the clay soil into the loose sand layer, which will prevent instantaneous compaction of the loose sand layer. Therefore, each project should carefully examine the underground soil profile and carefully design the installation method. In some cases, the design may not require the installation of porous drainage piles at the third position (3) or the last grid position (4).

[0063] Ground treatment below the embankment

[0064] RCCM can be used under mechanically stable walls (e.g., reinforced earth walls) to reduce and limit their settlement and also produce the required stability. Slopes that were found to have insufficient safety factors based on slope stability analysis can produce the required safety factors against landslides when densified using RCCM. Road embankments and highway embankments built on very soft soil layers sometimes sink and settle several inches or feet or meters; the 2H:1V slopes that are usually set on the opposite side of the embankment are found to be unstable, so a very flat slope is required. In this case, RCCM densifies the weak soil or soft soil under the embankment and reduces the settlement to a reasonable range and also improves the slope stability of the embankment slope without the need for a flatter slope. Fig. 8A and Figure 8B A typical example is shown in Fig. 8A As shown, a layer of sand material (142) is first laid on very soft clay soil to build a low-height embankment, which can be equipped with equipment to install porous soil piles composed of compacted sand material. After the porous soil piles are installed, the embankment is further raised to full height by an additional layer (143). Figure 8B As shown, the clay soil is very weak and cannot even support a low embankment on which the equipment is placed, so porous spoil piles at a first position (or even a second position) can be installed before the low embankment, and then the embankment is further extended, and then the porous spoil piles at the second and third positions can be installed.

[0065] Rapid Consolidation Compaction Method (RCCM) can also be used in coastal areas where the embankment will be extended further into the sea to build new land for airports and housing projects, etc., and where the subsoil consists of loose sand and soft to very soft clay. Similarly, new islands can be built even in cases where the subsoil consists of loose and soft and very soft soils, as these subsoils can be densified by the Rapid Consolidation Compaction Method. To reduce the downward resistance of driving piles in clay and silty soils, sand wells or PVC drain pipes (drain boards) are installed and embankments are built on top of them to consolidate the clayey silty layer for a period of time, usually up to 90% consolidation, and then the embankment is sometimes removed and the piles are driven in. Instead of sand wells or drain boards, RCCM can be used to install porous drainage piles, which will quickly consolidate the layer without the need to build an embankment and wait for up to 90% consolidation. RCCM can be used very economically in any soil layer or intermediate geotechnical material layer that requires soil improvement to densify it and can also be used in existing methods that are in use, such as jet grouting columns, cement columns or lime columns mixed with clay materials or Geopiers or vibro replacement using vibrating probes or vibro, bottom feed or top feed stone columns, etc.

[0066] For example, the foundation treatment under the leaning or tilted building of the Leaning Tower of Pisa

[0067] There are many buildings around the world that lean during construction or after construction is complete. Ground treatment using a rapid consolidation and compaction method to install porous soil piles can improve the foundation soil, which also results in a significant reduction in the tilt angle and allows the leaning building to approach nearly vertical. There are many other buildings in the city of Pisa, Italy, that lean like the Leaning Tower of Pisa, but not to this extent. Before considering installing porous soil piles to reduce the tilt of the Leaning Tower of Pisa, porous soil piles were installed at other leaning buildings in the city of Pisa to verify the effectiveness of soil improvement to successfully reduce the tilt under the underlying underground conditions. In order to reduce the tilt angle of the Leaning Tower of Pisa, (i) lead sinkers were placed on the north side of the prestressed concrete ring surrounding the foundation of the Leaning Tower of Pisa, (ii) steel cables were fixed to the north side of the tower to restrict movement to the south, (iii) drill holes were installed on the north side to remove soil from the drill holes, and (iv) some excavation was performed in the east-west direction (Jamiolkowsky, et al., 1993). However, while construction as described above is permitted on the north side, no construction is permitted on the south side in order not to disturb the tower, and even underground exploration including static penetration is permitted only 10 to 20 meters from the south edge of the tower. Before installing porous spoil piles, it may be considered to add steel cables to secure the tower to further secure the tower with steel cables in the northeast and northwest directions. If permitted by the relevant authorities, it is worth considering Fig. 9 and Fig.10 The porous soil pile installation scheme shown is used to consolidate and densify the upper clay between EI.-7m and -18m (locally known as Pancone clay), which has a cone tip penetration resistance q of only 1 to 1.5 MPa. c (Jamiolkowsky, et al., 1993). It is recommended that the porous soil piles be installed at an inclination of about 1V:2H (or even between 1V:3H and 1V:1H if necessary) to achieve the densification of the upper clay (163) and possibly raise the foundation of the south side of the Leaning Tower of Pisa. When the upper clay (160) is densified, its bearing capacity increases, resulting in a reduction in the south side settlement. When the inclination angle decreases, the south side bearing pressure decreases, while the north side bearing pressure increases, resulting in more settlement on the north side of the tower foundation and less settlement on the south side. In addition, after stabilizing and densifying the upper clay (163), the tendency of further tilting on the south side of the tower foundation in the future is prevented. The following description is to illustrate the industrial application of foundation treatment under a skewed building to reduce its tilt. For this purpose, the Leaning Tower of Pisa was selected. The following steps are desirable implementation plans:

[0068] 1. Conduct underground exploration near the south side of the tower.

[0069] 2. Install instruments to monitor vibration and settlement around the tower at selected depths above and below ground level.

[0070] 3. Before and during implementation, radar measurements are taken at designated points around the tower above ground level.

[0071] 4. Fig. 9 Grid lines (151) and grid line intersection locations (150) are shown where porous spoil piles are installed.

[0072] 5. Fig.10 It shows that: (a) the ground height is El.3.0m (170), (b) the bottom height of the clay and sandy yellow silt (162) is El.-7m (171), (c) the bottom height of the upper clay (163) is El.-18m (172), (d) the bottom height of the middle clay (164) is El.-22.5m (173), (e) the bottom height of the middle sand (164) is El.-24.5 (173), and (f) the lower clay (166) is located below the middle sand (165).

[0073] 6. The outer diameter of the tower base (162) is 19.58m, and the center is a circular space with a diameter of 4.5m. Fig.10 Indicated by reference numeral 161 in the figure. It is recommended to first drive the non-discharge piles (120) to the bottom elevation of the tower foundation at an inclination of 1H:2V. Then, a pipe section (123) with a detachable end plate (124) and filled with compacted sand material is driven through the non-discharge piles (120) to penetrate a short distance into the intermediate clay (164). After this, the pipe section is pulled out from the ground and then the non-discharge piles are taken out. As shown in the figure, the porous discharge piles (125) numbered 1 to 5 are driven first. The pipe section (123) and the detachable end plate (124) are not shown in the figure.

[0074] 7. Install the porous soil drainage piles in sequence at the grid intersection position No. 1 15 meters away from the south edge of the leaning tower, then at the position No. 2 about 12 meters away from the south edge, then at the position No. 3 9 meters away from the south edge, at the grid position No. 4 6 meters away from the south edge, and at the grid position No. 5 3 meters away from the south edge, continuously monitor and observe the settlement, vibration and movement, and analyze the impact of the porous soil drainage piles installed around the tower when they are located close to the tower base.

[0075] 8. When the recorded data is analyzed to determine the safety of the tower and when it is found satisfactory after the installation of each porous spoil pile, the installation of the remaining porous spoil piles can be considered.

[0076] 9. If permitted by the authorities, the installation at the first position may consider the following sequence: first positions 6 to 13, then 14 to 21.

[0077] 10. After the data is analyzed and deemed satisfactory to proceed, installation at the third position may be considered in the following order: positions 22 to 27 may be considered, then 28 to 47. The third position may be considered after assessing the reduction in the inclination of the leaning tower.

[0078] 11. After the porous spoil pile construction is completed, underground detection is carried out to evaluate the performance improvement of the upper clay.

[0079] 12. Despite Fig.10 Only the inclined porous spoil piles are shown, but in addition Fig. 9 and Fig.10 In addition to those shown in , vertical porous spoil piles can also be installed outside the tower foundation to increase the density of the upper clay outside the tower foundation. Load distribution for a tower or any foundation is considered to occur at a slope of about 60 degrees.

[0080] 13. Instead of installing porous soil-displacement piles consisting of compacted sand columns, porous soil-displacement piles consisting of porous pipe sections with attached end plates or pipe sections with holes and containing compacted sand material and end plates may be considered, as these pipe sections do not need to be pulled out of the ground and do not involve the disturbance and noise associated with pulling pipe sections out of the ground. These porous soil-displacement piles are also driven through the interior of non-soil-displacement piles.

[0081] The dense soil beneath the sinking building

[0082] When a building such as a house or oil or water tank continues to settle on all sides, inclined porous spoil piles that penetrate all sides below the building can be installed to significantly prevent or reduce further settlement. The inclined spoil piles need to be installed in a specific order so that at all times, they are evenly and symmetrically positioned around the building. The porous spoil piles can be composed of compacted sandy soil columns and installed as described above. To reduce vibration, noise and interference, it is also possible to consider installing porous spoil piles that include porous pipe sections or pipe sections with small holes and end plates and filled with compacted sandy soil. All spoil piles are driven through the interior of non-soil piles. Selection is made for a specific site based on soil conditions and the environment surrounding the building.

[0083] Teachings of this application

[0084] The various aspects described in the above sections can be used alone or in other combinations for other types of applications. The teachings of the present application are not limited to the industrial applications described above, but may have other applications. Therefore, the teachings of the present application have many advantages and uses. Therefore, it should be noted that this is not an exhaustive list and may have other advantages and uses not described herein. Although the teachings of the present application have been described in detail for the purpose of illustration, it should be understood that these details are only for this purpose and that those skilled in the art may change them without departing from the scope of the teachings of the present application. In addition to the explicitly described combinations, the features described in the previous description / specification may be used in combination. Although attempts have been made to focus on those features of the present invention that are considered to be particularly important in the previous description / description, it should be understood that the applicant and the inventor claim protection for any patentable feature or feature combination mentioned above and / or shown in the drawings, whether or not it is particularly emphasized. The term "comprising" used in the claims does not exclude other elements or steps. The term "one" or "a kind" used in the claims does not exclude multiple. A component or other device may implement the functions of several components or devices described in the claims. Because of the variety of possible embodiments that may make up the above-described invention, and because various changes may be made to the above-described embodiments, it is to be understood that all matter described herein or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

[0085] References

[0086] Bowles, EBFoundation Analysis and Design, Fourth Edition, 1981, McGraw-Hill Book Company, New York, New York, USA.

[0087] Jamiolkowski, M., Lancelotta, R., and Pepe, C. (1993) "Leaning Tower of Pisa-Updated Information", Proceedings, Third International Conference on Case Histories in Geotechnical Engineering, June 1-4, 1993, SOA, St. Louis, Missouri, USA.

[0088] Kennedy,G.D.,and Woods,K.B.(1954).“Vertical Sand Drains,”HighwayResearch Board,Bulletin 90,Washington,D.C.,USA.

[0089] Mars,B.N.,“Compaction of Soil,”Patent No.US 4,126,007,issued onNov.21,1978,United States Patent and Trade Mark Office,Alexandria,Virginia,USA.

[0090] Peuchen,J.,Berghes,J.F.V.,and Coulais,C.(2010),“Estimation of u1 / u2conversion factor for piezocone,”Second International Symposium on ConePenetration Testing,California,USA.

[0091] Pile Dynamics,Inc.(2005)“GRLWEAP,Wave Equation Analysis of PileDriving”,Cleveland,Ohio,USA.

[0092] Prakash,D.and Gupta,R.C.(1972),"Laboratory Studies on FilterMaterials Placed at Ramganga Main Dam,"Indian Geotechnical Journal,Vol.2,No.3,July 1972,pp.203-219,New Delhi,India.Schaefer,V.R.,Berg,R.R.,Collin,J.G.,Christofer,B.R.,DiMaggio.J.A.,J,A,Filz,G.M.,Bruce,D.A.,and Ayala,D.(2016).“Ground Modification Methods-Reference Manual”,Volume 1,GeotechnicalEngineering Circular No.13,FHWA-NHI-16-027,US Department of Transportation,Washington,D.C.USA.

[0093] Seed,H.B.,and Idriss,I.M.(1971)“Simplified Procedure for EvaluatingSoil Liquefaction Potential”,JSMFD,ASCE,Vol.97,SM 9,Sept.,pp.1249-1273.

Claims

1. A rapid consolidation and compaction method for densifying various soil layers and intermediate geotechnical material layers in a soil deposit, the rapid consolidation and compaction method comprising using a porous soil displacement pile comprising a compacted sandy soil column, or a porous reinforced concrete pile with or without prestressing, or a porous third pipe section with attached end plates, or a fourth pipe section with small holes and attached end plates and filled with compacted sandy soil, for rapid consolidation to densify at least one clayey silt layer and to instantaneously densify at least one sandy soil layer, When the porous soil removal pile is a compacted sandy soil column, the rapid consolidation and compaction method includes: (i) wherein a non-displacement pile including a first pipe section is first driven into the ground, (ii) wherein a displacement pile comprising a second pipe section having a removable end plate attached thereto and filled with a compacted sandy soil layer is driven through the interior of the non-displacement pile into at least one soil layer or intermediate geotechnical material layer, (iii) wherein after driving said spoil piles as described above, a weight or hammer is placed on top of said compacted sandy soil in said second pipe section before pulling said second pipe section out of the ground, (iv) wherein during extraction of the second pipe section of the spoil pile from the ground, the removable end plate opens 100% of the interior area of ​​the second pipe section, wherein during the extraction of the second pipe section of the spoil pile, the weight or hammer is placed on top of the compacted sandy soil in the second pipe section to continue to push the compacted sandy soil vertically downward to fill the compacted sandy soil in the space previously occupied by the second pipe section, wherein the weight or hammer is placed on top of the compacted soil in the second pipe section during extraction of the second pipe section from the ground to prevent necking in the compacted sandy soil column, and (v) wherein after the second pipe section of the spoil pile is pulled out from the ground, the compacted sandy soil column is left in the ground, wherein the cross-sectional area of ​​the compacted soil column is equal to or greater than the internal area of ​​the second pipe section, wherein the compacted sandy soil column remaining in the ground after the second pipe section is pulled out acts as a porous soil removal pile, up to the depth to which the second pipe section of the soil removal pile is driven; When the porous earth-removal pile is a porous reinforced concrete pile with or without prestress, or when the porous earth-removal pile comprises a porous third pipe section with an attached end plate, or when the porous earth-removal pile comprises a fourth pipe section with small holes, an attached end plate and filled with compacted sandy soil, the rapid consolidation and compaction method comprises: (i) wherein a non-displacement pile comprising a first pipe section is first driven into the ground, and (ii) wherein the porous soil displacement pile is driven through the interior of the non-soil displacement pile into the at least one soil layer or intermediate rock material layer; wherein the porous soil removal pile displaces soil and intermediate geotechnical materials away from the soil removal pile and pushes the soil and intermediate geotechnical materials laterally away from the soil removal pile; wherein the porous spoil piles occupy spaces previously occupied by clay silt and generate excess pore water pressure in the saturated clay silt by pressurizing pore water present in pores of the saturated clay silt, and generate excess pore water pressure in the partially saturated clay silt; wherein the excess pore water pressure generated in the clay silt is rapidly dissipated by the flow of pressurized pore water through the porous soil drainage piles toward the ground or toward the sandy soil layer located underground, thereby densifying the clay silt; wherein the porous soil displacement piles occupy the space previously occupied by the sandy soil, thereby reducing the void volume of the soil matrix and instantaneously densifying the sandy soil; wherein no excess pore water pressure is generated in the sandy soil and, if generated, dissipates immediately; The porous reinforced concrete pile, the third pipe segment and the fourth pipe segment do not need to be pulled out from underground; wherein a plurality of said porous spoil piles are installed spaced apart in a grid pattern throughout the area to be densified; The porous soil removal piles are installed vertically or obliquely.

2. The rapid consolidation and compaction method for densifying various soil layers and intermediate geotechnical material layers in soil sediments according to claim 1, the rapid consolidation and compaction method comprising: wherein the non-displacement piles are first driven into the ground to minimize the level deviation of the ground or the top of the layer to be densified; Wherein, if the non-drainage piles are not driven into the ground but the drainage piles are driven directly, or if the non-drainage piles are not driven to a depth sufficient to prevent leveling, the amount of compaction will be smaller because the soil displaced by the drainage piles is the sum of the reduction in voids in the soil plus the soil leveled at the ground or on top of the layer to be compacted.

3. The rapid consolidation and compaction method for densifying various soil layers and intermediate geotechnical material layers in soil sediments according to claim 1, the rapid consolidation and compaction method comprising: wherein the sandy soil is filled in layers, and each layer is compacted inside the second pipe section; wherein the sandy soil inside the second pipe section is compacted at the same position as the second pipe section to be driven into which the sandy soil is filled and compacted or at another position different from the second pipe section to be driven into which the sandy soil is filled and compacted, wherein the gradation, i.e., particle size distribution, of the compacted sandy material is designed to allow free flow of excess water to dissipate excess pore water pressure while preventing fine particles of the in-situ soil from migrating therein; The porous reinforced concrete pile, or the third pipe section, or the fourth pipe section is used as the porous drainage pile if (1) it can be driven into the soil by the pile hammer without exceeding the allowable pile driving stress, (2) free drainage and water flow are allowed while preventing the migration of fine particles of the in-situ soil, and (3) the small holes in the fourth pipe section are relatively small so that the sandy soil can be retained in the fourth pipe section during compaction.

4. The rapid consolidation and compaction method for densifying various soil layers and intermediate geotechnical material layers in soil sediments according to claim 3, the rapid consolidation and compaction method comprising: The sandy soil in the second pipe section is compacted using one of the following three methods: (i) wherein in the first method, the sandy soil is filled in the second pipe section in layers and each layer is compacted and densified by the falling of the hammer or weight, wherein the hammer or weight is connected to the boom of a crane or to a pile hammer via a connecting rod connecting the weight or hammer; (ii) wherein in the second method, each layer of sandy soil is filled in the second pipe section and the hammer or weight is placed on top of the sandy soil in the second pipe section, wherein a plane vibrator is attached to the side of the second pipe section and the second pipe section is vibrated to compact and densify each layer of sandy soil inside the second pipe section; (iii) wherein in the third method, each layer of sandy soil is filled in the second pipe section, and the hammer or weight is placed on top of the sandy soil in the second pipe section and the hammer or weight is vibrated to densify the sandy soil inside the second pipe section; wherein using these methods, the sandy soil in the second pipe section is compacted to a relative density that reaches a medium-compacted, compacted or extremely compacted sandy soil condition; wherein (a) the sandy soil in the second pipe section is compacted to a specific relative density, and (b) the spacing and diameter of the porous spoil piles in the grid pattern depend on the subsoil conditions of the site and the specifications to which the subsoil layers of the site are to be densified; wherein porous spoil piles having a relative density greater than that of the densified in-situ soil densified by the rapid consolidation compaction method are used as reinforcement to share more of the load of the embankment or building foundation than the densified in-situ soil shares, thereby reducing the total settlement of the building or embankment; During compaction of the sandy soil, the second pipe section is laterally supported to maintain the second pipe section in a vertical position.

5. The rapid consolidation and compaction method for densifying various soil layers and intermediate geotechnical material layers in soil sediments according to claim 1, the rapid consolidation and compaction method comprising: wherein the removable end plate is attached to the end of the second pipe section using one of the following three different methods; (i) wherein in the first method, the removable end plate is attached to the second pipe section by a hinged connection, wherein during the extraction of the second pipe section from the ground, the bottom of the second pipe section is completely opened because the removable end plate becomes vertical on one side of the hinged connection, thereby opening the bottom of the second pipe section in the vertical pile, wherein, for the inclined pile, the removable end plate with the hinged connection is aligned in the longitudinal direction of the inclination of the spoil pile, thereby opening the bottom of the second pipe section; (ii) wherein in the second method, a removable short pipe section is connected to the removable end plate and then the two are inserted together into the end of the second pipe section, The short pipe section is closely attached to the inside of the second pipe section, or the short pipe is attached to the second pipe section by a thin aluminum rivet, and when the second pipe section is pulled out, the thin aluminum rivet breaks. wherein during the extraction of the second pipe section from the ground, the second pipe section is fully opened and the short pipe section attached to the removable end plate is left at the bottom of the compacted soil column; (iii) wherein in the third method, a plurality of connecting rods are first bolted to the removable end plate at the bottom of the second pipe section, and then the connecting rods are fastened to the top of the second pipe section, wherein when the second pipe section filled with the compacted sandy soil has been driven into the ground, the bolts at the top of the second pipe section are loosened to allow the connecting rod and the attached detachable end plate to be detached from the second pipe section during the extraction of the second pipe section, wherein, when the second pipe section is pulled out from underground, the connecting rod and the removable end plate remain underground; For all of the above situations, no matter which one is selected, after the second pipe section has been taken out from the ground, the compacted sandy soil column installed underground acts as the porous soil removal pile.

6. The rapid consolidation and compaction method for densifying various soil layers and intermediate geotechnical material layers in soil deposits according to claim 5, wherein in order to transport the second pipe section filled with the compacted soil to another location, the rapid consolidation and compaction method comprises: wherein when the second pipe section has been filled and compacted at a position different from the position where it is to be driven, then for the first method, in addition to the hinged connection on one side, at least one angle profile is bolted to the removable end plate and to the second pipe section on the diametrically opposite side of the hinged connection, wherein after attaching at least one angle profile to the second pipe section and the removable end plate, the second pipe section filled with the compacted sand material is moved to the position where it is to be driven; wherein when the second pipe section has been filled and compacted at a location different from the location where it is to be driven, then for the second method, the short pipe section is attached to the removable end plate and the short pipe section is connected to the second pipe section by a plurality of bolts to keep the compacted sandy material in the second pipe section in place, The bolts are removed when the second pipe section has been transported to the position where the second pipe section is to be driven and when the removable end plate is in contact with the ground.

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