WALL STRUCTURAL MEMBER AND METHOD FOR CONSTRUCTING A WALL

STRUCTURE

RELATED APPLICATION

This application claims the benefit of U.S. Patent Application Ser. No. 11/307,272 filed January 30, 2006, and U.S. Provisional Application Ser. No. 60/649,376 filed on February 1, 2005, each of which is incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to wall structures and a method of constructing the same. The invention provides a wall structure constructed in the ground using a structural member having pre-attached components that are protected during construction of the wall structure.

BACKGROUND OF THE INVENTION

Foundations for large structures, such as high-rise buildings, stadiums, bridges, tunnels, or other similar structures, are often constructed underground. Subways, tunnels, or subterranean structures, are by their nature usually constructed underground. Since these structures are frequently constructed in urban or developed areas, lateral support is generally provided for adjacent structures, streets or utilities, and the surrounding ground during construction. Several methods are commonly used to provide lateral support, including installation of sheet piles, soldier piles and lagging, and concrete wall structures. However, installation of sheet piles may cause considerable vibration and noise, disrupting nearby businesses or residences. Soldier piles and lagging may drain the surrounding soil, causing the ground and adjacent buildings to settle.

Concrete wall structures, on the other hand, may be constructed with minimal noise, vibration, or disruption, and can be incorporated into the foundation or finished structure. Concrete wall structures can contain structural beams and a reinforcing cage integrated with the concrete wall to provide additional strength. Concrete wall structures can also be constructed in unstable soil environments or under water, and do not drain the surrounding

soil. For example, a slurry displacement method or tremie system may be used to place concrete. U.S. Patent No. 3,412,562 to S. Dougherty and assigned to Ben C. Gerwick, Inc., describes such methods and systems and is incorporated herein by reference in its entirety.

Concrete wall structures suffer from other disadvantages. Reinforcement continuity is typically desired, allowing for vertical shear transfer, horizontal tension transfer, and moment continuity along the wall structure. However, reinforcement continuity has posed a significant problem in the art, particularly since wall structures may comprise multiple wall sections constructed at different times. In addition, the interface between the concrete wall and structural beams may provide a path for water flow through the wall structure. Changes in ambient temperature can cause unequal expansion and contraction of the structural beams and concrete wall. As a result, water may leak through a gap between a structural beam and concrete wall.

Reinforcement continuity is commonly provided by embedding rods in abutting wall sections. The rods are usually embedded in a first wall section before being embedded in a second wall section, and are implemented during construction of the wall sections in the ground. Methods have been developed that allow the rods to protrude from the first wall section without being fully embedded in the concrete of the wall, but these methods often rely on elaborate systems to partition the first wall section while the concrete hardens. The protruding rods are also exposed and susceptible to damage during construction of the second wall structure. Care usually must be taken not to bend or damage the rods during excavation for the second wall section, adding to the complexity of the construction process. In addition, these methods typically provide little or no moment capacity horizontally along the wall.

Water stops are known in the art for preventing water seepage through concrete joints. Water stops are commonly employed to seal joints between abutting concrete sections. Typically the water stops cover the exposed joint, or are incorporated into the joint. Water stops can also be embedded in abutting wall sections. However, embedding water stops into abutting wall sections suffers from many of the same difficulties discussed above with respect to reinforcement continuity. For example, the portion of the water stop that protrudes from the first wall section may be torn or damaged during construction of the second wall section.

Attaching components, such as reinforcing bars or water stops, to a structural beam during construction can be a complicated process. For example, weak concrete is often used to set the structural beam in a specific alignment in the ground. Slurry may be used to maintain the trench or the hole. The dimensions of the trench or hole may also make attachment difficult. However, many methods of constructing wall structures rely on attachment of components, particularly for reinforcement continuity, during construction. This may be because components that are pre-attached to the structural beam can be damaged by insertion of the structural beam into the ground, alignment of the beam, and by construction and excavation equipment. If weak concrete is used to set the structural beam, it may encase the pre-attached components before they can be embedded in the concrete wall.

Accordingly it would be desirable to provide a system that protects components pre-attached to a structural beam during construction of a wall structure in the ground. It would be further desirable to provide a system that permits continuity between a structural beam and a concrete wall of a wall structure, and along the wall structure. It would be also desirable to provide a system that inhibits water flow through the interface between a structural beam and a concrete wall of a wall structure. It would be further desirable to provide a method of constructing a wall structure in the ground or an extended wall structure including structural beams having pre-attached water stops or reinforcing bars according to the aforementioned system.

SUMMARY OF THE INVENTION

In one embodiment, a structural member that can be inserted into the ground and having one or more attached components is provided. The structural member comprises a removable shield that is coupled to a structural beam, defining a chamber between the shield and the structural beam. The components are attached to the structural beam so that they are disposed in the chamber when the shield is coupled to the structural beam. The shield is configured to be removable from the structural beam when the structural beam is inserted into the ground. The components may include reinforcing bars to provide reinforcement

- A - continuity in a wall structure. The components may also include water stops to reduce or eliminate water leakage through the wall structure.

A method for constructing a wall structure in the ground using a first structural member is also provided. The method can further include a second structural member. In addition, a method for constructing an extended wall structure in the ground is provided.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a cross-sectional view of a structural member according to one embodiment.

Figure 2 is a cross-sectional view of a structural member according to another embodiment.

Figure 3A is a top-view of one stage in the construction of a wall structure in the ground according to another embodiment.

Figure 3B is a top-view of a second stage in the construction of the wall structure in the ground depicted in Figure 3 A.

Figure 4A is a top-view of one stage in the construction of an extended wall structure according to yet another embodiment.

Figure 4B is a top-view of a second stage in the construction of the extended wall structure depicted in Figure 4A.

Figure 4C is a top-view of a third stage in the construction of the extended wall structure depicted in Figure 4A.

Figure 5 A is a top-view of one stage in the construction of a circular extended wall structure according to another embodiment.

Figure 5B is a top-view of a second stage in the construction of the circular extended wall structure depicted in Figure 5A.

Figure 5C is a top-view of a third stage in the construction of the circular extended wall structure depicted in Figure 5A.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will now be described in detail with reference to the drawings, which are provided as illustrative examples so as to enable those skilled in the art to practice the invention. It is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the spirit and scope of the present invention.

A cross-section of a structural member for use in a wall structure constructed in the ground according to one embodiment is depicted in Figure 1. Structural member 100 comprises a structural beam 110. Structural beam 110 has a length extending in a longitudinal direction (normal to the surface of the page). A shield 120 is coupled to structural beam 110, defining a chamber 152 between shield 120 and structural beam 110. Components are attached to structural beam 110 and disposed in chamber 152, including reinforcing bars 132 and 134, and water stop 142. Shield 120 can be removed from structural beam 110 to expose chamber 152 and any components disposed therein. Shield 120 protects components attached to structural beam 110 and disposed in chamber 152 during construction of the wall structure, allowing use of structural beams having pre-attached components (i.e., components attached to the structural beam before the structural beam is disposed in the ground). Shield 120 may be removed at a specific stage in construction to expose the components; for example, so that the components may be embedded in the wall of the wall structure.

The structural beam may be a flanged beam, such as an H-beam or an I-beam, or may be a channel beam. Structural beam 110 depicted in Figure 1 is a flanged beam, having a first flange 112, a second flange 114 spaced apart and parallel to first flange 112, and a web 116 between first flange 112 and second flange 114. Web 116 is perpendicular to first flange 112. Structural beam 110 has a size and length that is sized according to the depth of the hole or

height of the planned wall structure. By way of non-limiting example, a typical structural beam may be 12 inches wide by 36 inches deep, and extend between 30 feet to 100 feet in length. It is to be appreciated that structural beam 110 may have a different size and length depending upon the requirements of a specific construction project. In addition, a bottom plate 160 may be attached to the bottom end of structural beam 110. Bottom plate 160 covers the entire cross-sectional area of structural beam 110. The shape of bottom plate 160 may be varied according to the cross-sectional area of the type of structural beam used.

Shield 120 may include additional elements to couple the shield to structural beam 110, and to further define chamber 152. Shield 120 depicted in Figure 1 includes a shield member 122, shield guides 124 and shield spacer 126, and shield stops 128. Shield member 122 has a length extending in a longitudinal direction, and extends the length of structural beam 110. However, the shield member may have a length longer or shorter than the structural beam. For example, if structural beam 110 protrudes out of the ground, shield member 122 may have a length shorter than structural beam 110 so that shield member 122 only extends to ground level. Alternatively, shield member 122 may be longer than structural beam 110, so that shield member 122 protrudes past structural beam 110. It is to be appreciated that shield member 122 may have a different length depending upon the requirements of a specific construction project.

Shield member 122 is coupled to structural beam 110 in the following manner. Shield guides 124 and shield spacer 126 spacer are attached to shield member 122. Shield guides 124 aid in alignment of the shield member 122 with first flange 112 and second flange 114 of structural beam 110. Shield spacer 126 spaces shield member 122 from web 116. Shield stops 128 are attached to first flange 112 and second flange 114 to aid in alignment of shield member 122, and to help hold shield member 122 in place next to structural beam 110. Shield member 120 may also include attachment points or hooks at a top end to allow for construction equipment, such as a crane or a winch, to aid in placement or removal of the shield member.

According to one embodiment, first flange 112, second flange 114, shield stops 128, and bottom plate 160 work in combination to hold shield member 122 in place next to structural beam 110, but shield member 122 is not rigidly attached to structural beam 110. Shield

member 122 can be removed by sliding shield member 122 in the longitudinal direction toward the top end of structural beam 110. Thus, shield member 122 can be removed from structural beam 110 when structural member 100 is placed in the ground. Moreover, because shield member 122 is removed by sliding along the length of structural beam 110, shield member 122 may be removed when the structural member is placed in a constricted space that does not allow for other methods of removal (i.e., a hole diameter roughly equal to the width of structural beam 110).

According to another embodiment, shield member 122 may be temporarily fastened to structural beam 110, such as by bolts, clamping, welding, or other method known in the art, to aid in handling and placement of structural member 100, and later unfastened for removal. In yet another embodiment, shield stops 128 may be detached from structural beam 110 to facilitate removal of shield member 122, such as by allowing shield member 122 to be removed laterally from structural beam 110 into an open cavity or trench. It is to be appreciated that shield 120 can be coupled to structural beam 110 in a variety of different ways, and that shield 120 might include all, some, or none of the elements described above without departing from the scope of the invention. In addition, it should be realized that shield 120 can be removed from structural beam 110 in a variety of different ways, and that the above embodiments are provided as illustrative examples. Shield 120 is therefore adaptable to the requirements of a specific construction project.

It can be seen that when shield 120 is in place next to structural beam 110, shield 120 and structural beam 110 define a chamber 152. In particular, as depicted in the embodiment shown in Figure 1, chamber 152 is defined by shield member 122 and web 116. Chamber 152 extends in the longitudinal direction, and extends the length of shield member 122. If shield member 122 extends the length of structural member 110, chamber 152 may also extend the entire length of the structural beam. Chamber 152 is bounded on the bottom end by bottom plate 160. Chamber 152 may be divided into vertical sub-chambers, such as by shield spacer 126, but this is not necessary. According to an alternate embodiment, shield spacer may not extend the entire length of shield member 122, or might be omitted entirely from the shield 120 (e.g., shield guides 124 may serve as a shield spacer). In yet another embodiment, chamber 152 may be divided horizontally separated sub-chambers. Thus,

shield 120 and structural member 110 may be selected to define a specific shape or type of chamber depending upon the requirements of a specific construction project.

Chamber 152 is substantially enclosed by shield 120 and structural member 110. Removing the shield exposes the chamber. Referring to Figure 1, when shield member 122 is in place next to structural beam 110, chamber 152 is protected. For example, shield member 122 can be adapted to prevent intrusion of the ground, construction equipment, excavation equipment, and liquid or semi-liquid material into the chamber. Thus, components may be attached to structural beam 110 and disposed in chamber 152 before construction commences, and can be protected during construction until they are needed at a specific stage of construction. At that stage, the shield may be removed from the structural beam to expose the chamber and components. For example, the shield may be removed after excavation of a cavity or trench for the wall of the wall structure, and before formation of the wall, so that the concrete of the wall flows into the chamber as it is being placed in the cavity, embedding the components.

According to one embodiment, components disposed in chamber 152 may include reinforcing bars 132 and 134. The reinforcing bars may be part of a reinforcing bar assembly 130 that includes a plurality of reinforcing bars attached to web 116 along the length of structural beam 110 (i.e., in the longitudinal direction). Reinforcing bars of reinforcing bar assembly 130 are attached so that they are generally perpendicular to web 116, and so that they protrude into chamber 152. Reinforcing bars of reinforcing bar assembly 130 are used in conjunction with a reinforcing cage to reinforce the wall structure, and to provide continuity of shear reinforcement at the interface between the structural beam and the wall. The reinforcing bars should overlap with corresponding reinforcing bars of the reinforcing cage to fully develop the tension capacity of the reinforcing bars at the structural beam. The amount of overlap required is a function of the type and proximity of the two bars. For conventional reinforcing bars, the amount of overlap is typically 30 to 40 times the diameter of the bars. For headed reinforcing bars the amount of required overlap is substantially reduced. Reinforcing bars 132 and 134 shown in Figure 1 are headed reinforcing bars, but it is to be appreciated that in an alternate embodiment conventional reinforcing bars may be used.

The reinforcing bar assembly provides reinforcement continuity between the structural beam and the wall. Wall structures that do not have continuity at this interface usually do not allow for vertical shear transfer, horizontal tension transfer, and moment continuity horizontally across the wall structure, or moment continuity at the structural beam. This is particularly important in extended wall structures comprising multiple wall sections. Structural member 100 provides reinforcement continuity via reinforcing bar assembly 130 in an effective and efficient manner. For example, reinforcing bar assembly 130 does not require an elaborate system to partition a wall section, and the reinforcing bars are protected during construction of the wall structure. In addition, headed reinforcing bars of the reinforcing bar assembly provide for moment capacity horizontally along the wall. Thus, reinforcing bar assembly 130 may be pre-attached to structural beam 110 and protected during construction by shield 120, making use of the structural member simple and cost-effective.

According to another embodiment, components disposed in chamber 152 may include a water stop 140. As depicted in Figure 1, water stop 140 may include additional elements, such as a water stop element 142 and a water stop attachment 144 to attach water stop element 142 to web 116. Water stop 140 is attached along the entire length of structural beam 110. Water stop element 142 seals the interface between the structural beam and the wall when it is embedded in well-compacted concrete of the wall. Water stop element 142 also inhibits water flow by increasing the distance water must flow along the interface between the structural beam and the wall. The water stop may have a variety of cross- sectional shapes to facilitate this function, and to help anchor the water stop in the wall, and might include one or more vanes 146, or include ribs. In an alternate embodiment, water stop 140 may be attached over a shorter length of structural beam if, by way of non-limiting example, water will be present only along a shorter length of the structural beam. In another embodiment, water stop 140 may be attached to structural beam 110 at other locations, such as first flange 112 or second flange 114, which do not interfere with the operation of shield 120. In an yet another embodiment the water stop assembly may include multiple water stops, such as is depicted in Figure 2, to further reduce water flow along the interface between the structural beam and the wall. If multiple water stops are used, each water stop should be firmly and completely embedded in well-compacted concrete. Water stops that are

attached too closely together may collectively impede the flow of concrete and prevent each other from being firmly and completely embedded, reducing their effectiveness.

Water stop 140 reduces or eliminates potential leakage through the wall structure. Structural member 100 thus provides an effective and efficient way to seal the interface between the wall and structural beam, which is a potential cause of water leakage through the wall structure. In addition, water stop 140 may be pre-attached to structural beam 110 and protected during construction by using shield 120, so that use of the structural member is simple and cost-effective.

As depicted in Figure 1, reinforcing bar assembly 130 and water stop 140 do not extend past first flange 112 and second flange 114. Thus, reinforcing bars 132 and 134 and water stop element 142 are disposed in chamber 152 when shield member 122 is in place next to structural beam 110. In another embodiment, water stop element 142 may be constructed from a deformable elastic material which is coiled or compressed when the shield is in place. When the shield is removed, the water stop can expand past the edges of the first or second flanges. According to yet another embodiment, the shield can be modified to create a larger chamber to accommodate components that extend beyond the first and second flanges. Figure 2 depicts a modified shield 120, where shield member 122 extends beyond first flange 112 and second flange 114, forming a larger chamber 152. Modified shield 120 preferably does not increase the maximum width of structural member 100. By way of non-limiting example, if the width of shield spacer 126 is equal to or smaller than one-half the width of structural beam 110 (i.e., one-half the width of web 116), structural member 100 can still be placed in a hole having a diameter roughly equal to the width of structural beam 110. It is to be appreciated that shield 120 may be modified in a variety of different ways, and that the above embodiments are provided as illustrative examples. Thus, shield 120 can be modified according to the requirements of a specific construction project.

Structural beam 110 is steel. Structural beam 110 might alternatively be pre-cast concrete, pre-stressed concrete, or other suitable material, such as a composite, that can handle loads imposed on the finished wall structure. It is to be appreciated that a structural beam having a cross-section different from the cross-section of structural beam 110 may also be used, and

that the structural beam does not need to be a flanged beam or channel beam. A shield may be constructed to work a variety of different structural beams and structural beam cross- sections.

Shield 120 is steel. The shield and elements of the shield, including shield member 122, shield spacer 126, shield guides 124, and shield stops 128, may be constructed from any other suitable material known in the art. By way of non-limiting example, shield member 122 can be constructed from any material strong enough to resist damage from construction equipment, from excavation equipment, and from the ground itself. According to one embodiment, shield member 122 is solid or continuous along its length so that it can resist intrusion of liquid or semi-liquid material into chamber 152. For example, a weak hardenable material is often used to set the structural member in a particular alignment in the ground. Shield member 122 is constructed so that little or none of this material enters chamber 152, or so that this material does not encase reinforcing bar assembly 130 or water stop 140. In another embodiment, shield member 122 might be discontinuous, provided that the shield member still protects chamber 152. For example, shield member 122 might be discontinuous to reduce weight and facilitate handling, such as by having through-holes, if weak concrete or other weak hardenable material is not used to set the structural member. Shield stops 128 are coupled to structural beam 110 by welding. Alternate means of coupling, such as bolting, may also be used. Similarly, shield guides 124 and shield spacer 126 are attached to shield member 122 by welding, but may be attached by any other suitable form of attachment known in the art.

Bottom plate 160 is steel, but may be constructed from any material strong enough to resist damage from construction equipment, from excavation equipment, and from the ground itself. By way of non-limiting example, bottom plate 160 may be a plastic or composite material. Bottom plate 160 works in combination with shield member 122 and structural beam 110 to protect components disposed in chamber 152, particularly components disposed near the bottom end of the structural beam. Bottom plate 160 may be attached to structural beam 110 by welding, although another suitable form of attachment known in the art may be used.

Reinforcing bars of reinforcing bar assembly 130, such as reinforcing bars 132 and 134, are constructed from carbon steel and are attached to web 116 of structural beam 110 by welding. Water stop 140 may be constructed from various materials or composites. In one embodiment, water stop element 142 is constructed of a deformable elastic material such as a rubber or plastic to permit the water stop to stretch or compress in response to expansion or contraction of the wall structure. Water stop attachment 144 may be a backing bar attached to structural beam 110 that securely and continuously clamps water stop element 142. A water stop constructed with a deformable elastic material possesses the additional advantage of being compressible. The pressure of the initial head of liquid concrete of the wall encases the water stop and compressed the deformable elastic material. When the concrete solidifies, the compressed water stop exerts a constant pressure against the concrete, sealing the interface between the water stop and wall and inhibiting water flow through the wall structure. In another embodiment, water stop element 142 may be constructed from a rigid material, such as a copper or steel plate, and be attached to web 116 by continuous welding along the length of structural beam 110. In this embodiment water stop element 142 and water stop attachment 144 can be the same structure.

It is to be appreciated that according to various embodiments of the invention, the structural member may include multiple components, such as both a reinforcing bar assembly and a water stop, or may only include one component. The type and number of components attached to the structural beam may be varied according to the requirements of a specific construction project. In addition, the shield and components may be attached to either side of the structural member. Referring to Figure 1, structural member 100 includes a shield, a reinforcing bar assembly, and a water stop, located on both sides of structural beam 110. Figure 2, in contrast, shows a structural member having a shield and components located on only one side of the structural beam. The structural member of Figure 2 might be used at the end of a wall structure, for example, where additional components are not needed on the side of the structural beam opposite the wall. The description provided above is the same for the shield and components located on either side of structural member 100.

It is also to be appreciated that the methods of attachment discussed previously are not limited to a single type of attachment. For example, attachment by welding may include

welding by any type of arc welding, gas welding, or other welding method known in the art. In addition, attachment may include composite forms of attachment, such as by combination of bolting and welding, or other well-known attachment methods.

The abovementioned embodiments describe generally a structural member that provides a solution to problems existing in the art related to constructing wall structures in the ground. The structural member allows for efficient and cost-effective pre-attachment of components to a structural beam prior to construction, and provides a novel way of protecting those components from damage during the construction process. The structural member includes a shield that is robustly adaptable, simple to implement, and easy to remove; and can be used in a range of construction applications and in confined spaces. Embodiments of the structural member may include pre-attached reinforcing bars to provide reinforcement continuity between the structural beam and wall, along the wall structure, and across wall sections. The pre-attachment of reinforcing bars is an efficient and cost-effective way of providing reinforcement continuity in a wall structure. Other embodiments of the structural member may include pre-attached water stops to seal the interface between the structural beam and the wall, and to prevent water leakage through the wall structure. Still other embodiments may include both reinforcing bars and water stops, or other components. The structural member might include pre-attached sensing and monitoring devices; for instance, to monitor the load and/or conditions of the wall structure. While various embodiments of a structural member according to the invention have been described, it will be appreciated by those skilled in the art that changes to the embodiments may be made without departing from the principles and spirit of the invention.

The structural member described above, or an embodiment thereof, may be used to construct a section of a wall structure in the following general manner. The structural member is inserted into the ground with the shield in place. The structural member may be set using a weak hardenable material. A cavity is excavated in the ground adjoining the shield. Any material in front of the shield, including weak concrete material, is also excavated. The shield is removed from the structural beam, and the chamber and components attached to the beam are exposed to the cavity. A hardenable material is placed in the cavity, the hardenable material encasing any components in the chamber. The hardenable material is allowed to

harden, forming a wall in the cavity. The components attached to the structural beam are embedded in the wall, and the structural beam and wall form the section of the wall structure.

A method of constructing a wall structure in the ground using structural member 100 will now be described in detail with respect to Figures 3 A and 3B. Referring to Figure 3 A, a first structural member 200 and a second structural member 201 are inserted into ground 290 in holes 280 and 281, respectively. Ground 290 is typically the earth, but may be any material that allows for the formation of a wall structure below the surface of the material. For instance, the ground might be a mound of earth positioned specifically to construct the wall structure, or land-fill, artificial earth, or other man-made material. The ground might also be located in non-outdoor areas, such as within a structure (e.g., a stadium or a building) or in a subterranean space (e.g., a tunnel or other subterranean structure).

Holes 280 and 281 are spaced a distance that is comparable to the length of the planned wall structure or wall section, and are typically 3 meters to 6 meters apart. According to one embodiment, the planned wall structure is a vertical wall structure (i.e., perpendicular to the ground), the holes are vertical holes, and the first and second structural members are oriented vertically when inserted into the ground in the holes. In another embodiment, slanting wall structures, including horizontal wall structures, can be constructed that are offset from a vertical orientation, depending upon the requirements of a specific construction project. In this case, the first and second structural members are inserted into the ground in a non- vertical orientation that corresponds to the slant of the planned wall structure.

First structural member 200 comprises a structural beam 210, a shield 220 including a shield member 222, a reinforcing bar assembly 230, and a water stop 240. Reinforcing bar assembly 230 and water stop 240 are disposed in a chamber 252 formed between shield 220 and structural beam 210. First structural member 200 also comprises a bottom plate (omitted) attached to the bottom end of structural beam 210. Similarly, second structural member 201 comprises a structural beam 211, a shield 221 including a shield member 223, a reinforcing bar assembly 231, and a water stop 241. Reinforcing bar assembly 231 and water stop 241 are disposed in a chamber 253 formed between shield 221 and structural beam 211.

Second structural member 201 also comprises a bottom plate (omitted) attached to the bottom end of structural beam 211.

First structural member 200 is aligned in hole 280 such that a side 204 faces second structural member 201 in second hole 281. Similarly, second structural member 201 is aligned such that a side 205 faces structural member 200 in first hole 280. Sides 204 and 205 correspond to those sides of structural beam 210 and structural beam 211, respectively, having the shield, the reinforcing bar assembly, and the water stop. First and second structural members 200 and 201 are further aligned so that the flanges of structural beam 210 and structural beam 211 roughly correspond with a thickness of the planned wall structure.

At this stage of construction, shield member 222 and shield member 223 are kept in place next to structural beam 210 and structural beam 211, respectively. In this way, the components disposed in chambers 252 and 253 are protected from damage during insertion and alignment of first structural member 200 and second structural member 201; for example, from damage caused by falling objects or debris, construction equipment, or contact with the ground. Thus, reinforcing bar assemblies 230 and 231, and water stops 240 and 241, may be pre-attached to structural beams 210 and 211, respectively, before the first and second structural members are inserted into the ground. Pre-attachment of the components advantageously reduces cost and increases efficiency of the construction project, and provides additional benefits such as reinforcement continuity and reduction or elimination of water flow through the wall structure.

After alignment of first structural member 200 and second structural member 201, a weak hardenable material (not shown), such as a weak concrete, may be placed in holes 280 and 281 to set the first and second structural members. This concrete or other hardenable material is intentionally made weak (e.g., a foam type concrete with air bubbles) so that it may be excavated at a later time during construction. This weak hardenable material usually does not form a permanent part of the finished wall structure. Shield member 222 and shield member 223 are kept in place next to structural beam 210 and structural beam 211, respectively, and inhibit or prevent the weak hardenable material from entering chambers 252 and 253. Thus, a weak hardenable material may be used to set first structural member 200 and second

structural member 201 without encasing reinforcing bar assemblies 230 and 231, water stops 240 or 241, or other components disposed in chambers 252 and 253. This is particularly advantageous as it is difficult to expose an encased or embedded component efficiently and without causing damage to the component.

Referring now to Figure 3B, a cavity is 265 is excavated between first hole 280 and second hole 281. Cavity 265 substantially corresponds to the thickness and shape of the planned wall structure, and is excavated to a depth corresponding to a planned height of the wall. Typically this depth is the same as the depth of holes 280 and 281, and is approximately equal to the length of structural beams 210 and 211. Cavity 265 may be excavated using any excavation equipment used in construction, such as a clamshell bucket excavator, drill, milling device, backhoe, or pick and shovel, by way of non-limiting example. Cavity 265 is usually a trench, but might be a slot, panel, or other type of excavation in the ground.

At this stage of construction, shield member 222 and shield member 223 are kept in place next to structural beam 210 and structural beam 211, respectively, to prevent damage to the structural beams and any components disposed in chambers 252 and 253 during excavation. Any weak hardenable material located on side 204 and side 205 of holes 280 and 281 is also excavated. Excavation of the weak hardenable material from side 204 and side 205 exposes shield member 222 and shield member 223, respectively, to cavity 265.

After excavating cavity 265, shield members 222 and 223 are removed from structural beams 210 and 211. According to an embodiment, shield member 222 may be removed by sliding the shield along structural beam 210 in a longitudinal direction out of cavity 265. Similarly, shield member 223 may be removed by sliding the shield along structural beam 211 in a longitudinal direction out of cavity 265. Removing shield member 222 and shield member 223 exposes chambers 252 and 253, respectively, and thus exposes reinforcing bar assemblies 230 and 231, and water stops 240 and 241, to cavity 265. In another embodiment, shield stops (not labeled) in shields 220 and 221 may be detached so that shield members 222 and 223 can be removed laterally into the cavity, such as into an open trench.

A reinforcing cage 270 including a plurality of cage reinforcing bars 272 is set in cavity 265. Reinforcing cage 270 is aligned in cavity 265 so that cage reinforcing bars 274 overlap with reinforcing bar assembly 230 at one end of reinforcing cage 270, and so that cage reinforcing bars 275 overlap with reinforcing bar assembly 231 at the other end of reinforcing cage 270. The cage reinforcing bars are arranged in a lateral direction that is substantially orthogonal to the longitudinal direction, and are generally arranged in an orientation parallel to the reinforcing bars of reinforcing bar assemblies 230 and 231. Thus, where the wall structure is a vertical wall structure and the structural beams are oriented vertically, the cage reinforcing bars are typically horizontal reinforcing bars. The cage reinforcing bars and reinforcing bar assemblies may include headed reinforcing bars, as shown in Figure 3B. The reinforcing cage may be omitted if reinforcement continuity and wall reinforcement are not needed or desired for a specific construction project.

A hardenable material 267 is placed in cavity 265. Hardenable material 267 is placed in cavity 265 so that reinforcing bar assemblies 230 and 231, reinforcing cage 270, and water stops 240 and 241 are encased in the hardenable material. Hardenable material 267 is allowed to harden, forming a wall structure. Hardenable material 267 is typically a hardenable cementitious material, such as concrete or cement, by way of non-limiting example, that forms the wall between structural beam 210 and structural beam 211 of the wall structure. While the wall structure is formed in the ground, it is to be appreciated that the ground may be later excavated to expose the all or part of the finished wall structure. For example, the wall structure may form an exposed wall in a part of a larger structure, such as an underground parking garage.

In one embodiment, holes 280 and 281 may be formed by drilling or digging. The diameters of the holes are roughly comparable to the diagonal of the cross section of structural beams 210 and 211 plus an allowance for positioning tolerance of the hole excavation method. First and second structural members 200 and 201 may be inserted into the holes prior to alignment. In another embodiment, first and second structural members 200 and 201 may be driven into the ground to form first and second holes 280 and 281, respectively.

In one embodiment, holes 280 and 281, or cavity 265, may be maintained during construction in unstable soils to prevent the hole or cavity walls from collapsing. Often this is a concern where groundwater is encountered or where construction must take place under water. In such cases, a slurry mixture may be used to provide lateral support for the hole or cavity walls, during drilling, excavation, or placement of a hardenable material or weak hardenable material. Lateral support is generated by maintaining a slurry mixture level above the water level to produce a positive pressure on the sides of the hole or cavity. This positive pressure restricts water from entering the hole or cavity, and reduces the likelihood of collapse. Slurry mixtures may also induce caking along the walls of the hole or cavity to further restrict the entry of water. The same principles also reduce the likelihood of collapse where no water is present, but where the soil is unstable. The slurry mixture may be a mineral slurry, such as a Bentonite slurry or a driller's mud, or may be a polymer slurry, such as commercially available SuperMud manufactured by PDS Company or SlurryPro CDP manufactured by KB Technologies, Inc..

Slurry usage and slurry displacement methods, including tremie systems, are well known in the art. For example, slurry usage and displacement methods are described in U.S. Patent No. 3,412,562 to S. Doughty and assigned to Ben C. Gerwick, Inc., entitled "Structural Wall and Method", incorporated herein by reference. A tremie system typically uses a pipe or tube to place concrete in a hole or trench maintained with a slurry mixture, or to place concrete under water. A tremie pipe may comprise a pipe with an opening at both a top and a bottom end. The bottom end is placed near the bottom of the hole or trench, and wet concrete is introduced into the top of the pipe. The tremie pipe may be specially designed to facilitate this operation, such as by providing a conical top section to receive a charge of concrete. As the level of concrete rises, it buries the bottom end of the tremie pipe, and the tremie pipe is gradually raised. Slurry or water is displaced as the head of concrete grows. Placement of the concrete is continuous and without interruption. The tremie pipe is kept full with concrete, and the bottom of the tremie pipe remains buried in the growing head of concrete. Keeping the tremie pipe buried in the growing head of concrete prevents a charge of concrete in the tremie pipe from being washed out by the water or slurry. In this way, concrete may be deposited at the bottom of a hole or trench containing water or a slurry mixture.

Figures 3 A and 3B depict structural members including reinforcing bar assemblies and water stops. In another embodiment the structural members include only one type of component. Typically the first and second structural members will include matching components. Thus, if the first structural member has a reinforcing bar assembly, the second structural member will also have a corresponding reinforcing bar assembly. Similarly, if the first structural member has a water stop, the second structural member will also have a corresponding water stop. However, it should be appreciated that the type and number of components will be driven by the requirements of a specific construction project. If only the first structural member will be exposed to water, for instance, a wall structure might be constructed where only the first structural member includes a water stop. In addition, construction of the components may not be identical for each structural member. By way of non-limiting example, the first structural member may include a metal-type water stop, while the second structural member may include a deformable elastic material-type water stop, or may include additional or fewer water stops.

A method of constructing an extended wall structure in the ground using structural member 100 will now be described with respect to Figures 4A-4C. The method of constructing an extended wall structure is similar to the method of constructing a wall structure in the ground previously described in connection with Figures 3 A and 3B. Additional details regarding the steps of the current method may be found by referring back to that section.

Referring to Figure 4A, a plurality of structural members are inserted into the ground. Each of the structural members includes a shield on either side of the structural beam. In addition, each of the structural members may have reinforcing bar assemblies, water stops, or other components attached on either side of the structural beam. The structural members are placed in pre-drilled holes, or are driven into the ground. Some or all of the holes may be maintained with a slurry mixture, as required, to prevent intrusion of water or collapse of the hole.

The structural members are aligned so that the flanges of each structural beam roughly correspond with the thickness of the planned wall structure. A weak hardenable material may be placed in some or all of the holes, as required, to set the structural members. If a hole is

maintained with a slurry mixture, the weak hardenable material may be placed using a system.

Referring now to Figure 4B, a primary wall is constructed between alternate pairs of structural members according to the method described above in connection with Figures 3A and 3B. In other words, a primary cavity 365 is excavated between a first structural member 300 and a first adjacent structural member 301. Primary cavity 365 may be maintained with a slurry mixture, as required, to prevent intrusion of water or collapse of the cavity. Following excavation of the primary cavity, shields 321 and 322 on facing sides of the structural members are removed, while shields 325 and 326 on opposite sides of the structural members remain in place. For example, shield 321 is removed exposing components disposed in chamber 352, and shield 322 is removed exposing components disposed in chamber 353. A reinforcing cage 370 may then be set in the primary cavity and aligned with the reinforcing bar assemblies disposed in chambers 352 and 353 of structural beams 310 and 311, respectively. Next, a hardenable material is placed in the primary cavity, encasing the exposed reinforcing bar assemblies, water stops, and reinforcing cage. If the primary cavity is maintained with a slurry mixture, the hardenable material may be placed using a tremie system. The hardenable material is allowed to harden, forming a primary wall 368.

Primary walls are similarly constructed between other pairs of alternate structural members; for example, between structural member 303 and a corresponding adjacent structural member (not shown). These primary walls may be constructed concurrently with primary wall 368, or may be formed sequentially. At this stage of construction, the extended wall structure is composed of discrete primary wall structures as shown in Figure 4B.

Secondary walls are then formed to connect the primary wall structures and form the extended wall structure. Referring to Figure 4C, a secondary wall is formed between first structural member 300 and a second adjacent structural member 302 in a similar manner to the primary walls. First, a secondary cavity 366 is excavated between first structural member 300 and second adjacent structural member 302. If necessary, the cavity is maintained with a slurry mixture. Next, shield 325 and shield 323 are removed, exposing components of structural beams 310 and 312 to secondary cavity 366. A reinforcing cage may be set in the

cavity and aligned with the reinforcing bar assemblies. Next, a hardenable material is placed in secondary cavity 366, encasing the exposed reinforcing bar assemblies, water stops, and reinforcing cage. If the secondary cavity is maintained with a slurry mixture, the hardenable material may be placed using a tremie system. The hardenable material is allowed to harden, forming a secondary wall 369.

Secondary walls are similarly constructed between the other pairs of structural members; for instance, between structural member 301 and structural member 303. These secondary walls may be constructed concurrently with secondary wall 369, or may be formed sequentially. The secondary walls connect the primary wall structures and form a contiguous extended wall structure, as shown in Figure 4C.

A method constructing a circular extended wall structure using structural member 100 will now be described with reference to Figures 5A-5C. The method of constructing a circular extended wall structure is similar to the method of constructing an extended wall structure previously described in connection with Figures 4A-4C. Additional details regarding the steps of the current method may be found by referring back to that section.

Referring to Figure 5 A, a plurality of structural members, such as structural member 410 and structural member 411, are inserted into the ground. Each of the structural members includes a shield on either side of the structural beam. Each of the structural members may also include reinforcing bar assemblies, water stops, or other components attached on either side of the structural beam. The structural members are aligned so that the flanges of each structural beam roughly correspond with a perimeter and thickness of the planned circular extended wall structure. For example, the structural members are inserted and aligned along a desired radius, as shown in Figure 5A.

Next, primary walls are formed between alternate pairs of structural members according to the method described with respect to Figure 4B. Here, however, the primary walls are curved primary walls, such as primary wall 425 shown in Figure 5B. In addition, reinforcing cage 470 is a curved reinforcing cage that corresponds to the curvature of the desired wall section so that it may be set and aligned in the similarly curved primary cavity.

Secondary walls structures are then constructed between the other pairs of structural members. The secondary walls connect the primary wall structures to form a contiguous, circular extended wall structure, as depicted in Figure 5C.

Using structural members that include reinforcement assemblies attached on both sides of each structural beam throughout the circular extended wall structure provides additional benefits over other wall structures. In particular, the circular extended wall structure shown in Figure 5C acts as a composite cylinder rather than a series of adjacent panels, substantially increasing the bending and shear capacity of the wall structure. This increased capacity provides a significant benefit when the wall structure is used as a foundation for an overlying structure, for instance, when used as a foundation for a high-rise building or a bridge.

While the above method is described with reference to a circular extended wall structure, it is to be appreciated that the method may be used generally to construct a variety of curvilinear wall structures, and is not limited to construction of the wall structure shown in Figure 5C. In addition, the above methods may be used to construct composite wall structures that include both straight and curvilinear walls. Thus, the above described methods of constructing a wall structure using a structural member may be extrapolated to a broad range of construction applications.

Although the present invention has been particularly described with reference to the preferred embodiment thereof, it should be readily apparent to those of ordinary skill in the art that changes and modifications in the form of the details may be made without departing from the spirit and scope of the invention. It should be further apparent to those skilled in the art that the various embodiments are not necessarily exclusive, but that the features of some embodiments may be combined with the features of other embodiments while remaining with the spirit and scope of the invention.