Methods for reinforcing existing lattice frame structures having hollow steel primary elements, particularly steel towers with tubular legs

Abstract

A series of alternative related methods for reinforcing an existing lattice frame steel structure, having substantially vertical Hollow Primary Elements, offering the option to choose between improving only compressive load-bearing capacity of said hollow primary elements, or improving both their compressive and the tensile load-bearing capacities. The compressive load-bearing capacity of said primary elements is increased by filling their internal cavities with non-shrink cement-based grout, in a slow and low-pressure procedure, hence ensuring the applicability of the present invention to practically any existing steel structure with hollow primary elements, regardless of their capacity to withstand internal pressure. The tensile load-bearing capacity of all, or any part of said primary elements is increased by the insertion, prior to the grout-filling, of a longitudinal, continuous and substantially concentric tensile reinforcement member into each respective primary element, and anchoring it properly to its bottom. An axial pretension of predetermined magnitude is applied to the tensile reinforcement member prior to the grout-filling.

1 . A method for reinforcing an existing lattice frame steel structure or tower ( 10 ) having substantially vertical Hollow Primary Elements ( 11 ), by filling the continuous longitudinal cavities of said Hollow Primary Elements with a non-shrink cement-based Grout, in a slow and low-pressure procedure, and in a sequential order, wherein said method comprises:
 a. Gaining access to said continuous longitudinal cavity of said respective Primary Element ( 11 ) through an Inlet Opening ( 16 ) located at its top, either by removing a cap plate or another bolted element sealing said existing Inlet Opening ( 16 ), or otherwise cutting or drilling such Inlet Opening through the top of said Primary Element ( 11 ) to be reinforced;   b. Lowering an Inserted Hosepipe ( 22 ) into each respective said Primary Element ( 11 ) to be reinforced, through said respective Inlet Opening ( 16 ), each of said Inserted Hosepipe ( 22 ) being long enough to reach substantially the bottom of said respective Hollow Primary Element ( 11 ), such that a relatively short part of said inserted Hosepipe ( 22 ) projects outward from the top of respective Primary Element ( 11 );   c. Sealing (in as much as necessary) any openings at the bottom of said Hollow Primary Elements ( 11 ) or at any higher point, through which the grout might leak out, except for the Inlet Opening ( 16 );   d. Preparing a Grout-Feeding Subsystem comprising:
 (i) A Bottom Grout Pump ( 24 ), which is a high-pressure grout-pump (typically of a type readily available in the market), located at ground level, near a Grout Mixing Device ( 25 ) (also typically of a type readily available in the market). Grout Pump ( 24 ) and Grout Mixing Device ( 25 ) may be combined in the same machine; and 
 (ii) A substantially vertical Exterior Grout Pipe ( 27 ), which is typically a flexible, high pressure hose available in the market as an accessory of Bottom Grout Pump ( 24 ), but may also be made of a tailored, rigid metallic pipe-line, laid between Bottom Grout Pump ( 24 ) and substantially the top of the Structure ( 10 ) being reinforced, its bottom end being connected to Outlet Stub ( 26 ) of Pump ( 24 ), and its top end being connected to one of the top intake-ends of said Inserted Hosepipes ( 22 ), through a Step-Down Hose-Coupler ( 28 ), fitted to engage the larger cross-section of Grout Pipe ( 27 ) on one side, and the smaller cross-section of Hosepipe ( 22 ) on the other; 
   e. “Feeding” said Bottom Grout Pump ( 24 ) with appropriate volume of fresh Grout mix, prepared using said Grout Mixing Device ( 25 ) in timed batched, as necessary to match the pace of the Grout filling process;   f. Pumping the Grout through said Exterior Grout Pipe ( 27 ) up to the top of Structure ( 10 ) and further into said respective Hollow Primary Element ( 11 ), through said Inserted Hosepipe ( 22 ), at such a slow pace (including possible planned pauses) that ensures that the height of the fresh Grout (i.e. the not yet hardened grout) within the Hollow Primary Element ( 11 ) does not exceed a predetermined value. During this process of grout filling of a single Hollow Primary Element ( 11 ), Hosepipe ( 22 ) is being retracted gradually upwards through said Inlet Opening ( 16 ), at a pace that matches the raise of the grout level within the respective Primary Element ( 11 ). Depending on the characteristics of Hosepipe ( 22 ), its retracted and exposed portion may be collected in hoops substantially at the top of Structure ( 10 ), or alternatively the exposed portion being cut off, from time to time, and the top end of the remaining Hosepipe ( 22 ) reconnected to said Grout-Feeding Subsystem;   g. Following the complete filling of the first Hollow Primary Element ( 11 ) with grout, up to the prescribed final level, repeating the procedure described in points e & f above for each of the other Hollow Primary Elements ( 11 ), in a sequential order.   
     
     
         2 . A method according to  claim 1 , wherein the handling of said Inserted Hosepipe ( 22 ) is assisted by auxiliary means comprising:
 a. Fixing a Hand Winch ( 100 ), equipped with compatible thin Winch Rope ( 101 ) with length equal at least to substantially the initial length of Inserted Hosepipe ( 22 ), above said Inlet Opening ( 16 ) of respective Primary Element ( 11 ), with a relatively small vertical gap there between;   b. Attaching said Winch Rope ( 101 ) to respective Hosepipe ( 22 ), before or during its insertion into Primary Element ( 11 ), by means of an End Fastening Device ( 102 ) located near said Hosepipe's Outlet End ( 105 ), and a plurality of Intermediate Fastenings ( 103 ) located in certain appropriate intervals throughout the inserted length of Hosepipe ( 22 ) and Winch Rope ( 101 ). The selection of specific appropriate materials and shape for Fastening Devices ( 102 ) and ( 103 ) is significantly governed by the dimensional constraints inside the cavity of said Primary Element ( 11 ), and also by the materials of Hosepipe ( 22 ) and Winch Rope ( 101 );   c. Retraction of Hosepipe ( 22 ) is facilitated by turning Hand Winch ( 100 ), while said small vertical gap between Inlet Opening ( 16 ) and Hand Winch ( 100 ) allows dismantling each Intermediate Fastening ( 103 ) as soon as it is exposed, thus allowing handling of the exposed portion of said Hosepipe ( 22 ) independently from the auxiliary means described herein.   
     
     
         3 . A method according to  claim 1 , wherein said Grout-Feeding Subsystem further comprises:
 (i) A grout Buffer Tank ( 20 ) of appropriate size, placed near the top of said Existing Structure ( 10 ) being reinforced, and having a bottom outlet nozzle; and   (ii) A Top Grout Pump ( 21 ) (electrical or manual), placed slightly lower than said Buffer Tank ( 20 ) and connected to said Tank's outlet nozzle, directly or through a relatively short pipe there between;   and wherein said top end of Exterior Grout Pipe ( 27 ), is placed right over said Buffer Tank ( 20 ) so as to feed it with fresh grout, such that Bottom Grout Pump ( 24 ) and Exterior Grout Pipe ( 27 ) are used only to “feed” Buffer Tank ( 20 ) with fresh grout at the required capacity, while Top Grout Pump ( 21 ) ensures required drive for the grout to flow along the entire length of Inserted Hosepipes ( 22 ), one of which is being connected directly to its outlet.   
     
     
         4 . A method according to  claim 3 , wherein said Grout-Feeding Subsystem does NOT include the Bottom Grout Pump ( 24 ) and the Exterior Grout Pipe ( 27 ), and instead the “feeding” of Buffer Tank ( 20 ) with fresh grout, which is being prepared utilizing said Grout Mixing Device ( 25 ) at ground level, is achieved by lifting the ready grout mix into said Buffer Tank ( 20 ) in buckets, utilizing any one of many practices exercised conventionally in the construction industry. 
     
     
         5 . A method according to  claim 4 , wherein said Grout Mixing Device ( 25 ) is located on an auxiliary platform, substantially at the top of said Existing Structure ( 10 ) being reinforced, such that it directly “feeds” Buffer Tank ( 20 ) with fresh grout, and wherein the dry grout bags may be positioned beforehand on said auxiliary platform or sufficiently close to it, so as to facilitate the mixing operation at the required pace. 
     
     
         6 . A method according to  claim 1 , wherein said filling of the cavities of said Hollow Primary Elements ( 11 ) with said Grout is done in an almost simultaneous manner (instead of sequentially), the method employing a plurality of said Inserted Hosepipes ( 22 ), such that each of said Hollow Primary Elements ( 11 ) has one of said Inserted Hosepipes ( 22 ) lowered there into, through its respective Inlet Opening ( 16 ), and the top intake end of each of said Inserted Hosepipes ( 22 ) is connected to said Grout-Feeding Subsystem only for a relatively short duration at a time, facilitating only partial filling of the respective Hollow Primary Element ( 11 ), following which the to intake end of another Inserted Hosepipe ( 22 ) is connected to said Grout-Feeding Subsystem only for a short duration, so as to facilitate similar partial filling of the other respective Hollow Primary Element ( 11 ), and this procedure is repeated with all said Inserted Hosepipes in a sequential and cyclic manner, maintaining the Grout level differences between the various Hollow Primary Elements within a predetermined value, until the grout level in all said Hollow Primary Elements ( 11 ) has reached the prescribed final levels. 
     
     
         7 . A method according to  claim 6 , wherein a Multi-Valve Distribution Block ( 23 ) is connected to the outlet of said Grout-Feeding Subsystem, the number of valves in said Distribution Block ( 23 ) being equal (or exceeding) the number of said Hollow Primary Elements ( 11 ) to be filled with Grout substantially simultaneously, and each of said top intake ends of Inserted Hosepipes ( 22 ) is connected to one respective valve in said Distribution Block ( 23 ), facilitating either simultaneous flow of the grout into all respective Hollow Primary Elements ( 11 ), or only into one of them at any given short duration, in a cyclic switching procedure, so as to achieve the same effect of almost simultaneous Grout filling at a higher comfort and speed. 
     
     
         8 . A method according to  claim 1 , wherein said filling, of said cavities, with said Gout, is monitored through a specialized Remote Portable Camera System, so as to verify that it is free of any unforeseen obstructions, the Camera (or plurality of cameras, respectively) of said System being appropriately small and durable, having an integrated flashlight; said Camera is lowered into the respective Hollow Primary Element ( 11 ) through said Inlet Opening ( 16 ) alongside with said respective Inserted Hosepipe ( 22 ), so as to provide a real-time, close-range electronic image of the filling process, and is also retracted upwards together with the respective Inserted Hosepipe ( 22 ), so as follow the rise of the grout level inside respective Primary Element ( 11 ) being filled. 
     
     
         9 . A method according to  claim 8 , wherein said Remote Portable Camera System further facilitates recording of the video signals obtained through said Camera (or plurality of cameras), thus the entire said Grout-filling process may be electronically-documented. 
     
     
         10 . A method for increasing the tensile load bearing capacity of all, or part of the substantially vertical Hollow Primary Elements ( 11 ) of an existing lattice frame steel structure ( 10 ), to be used in conjunction with grout-filling of said Hollow Primary Elements ( 11 ) performed by any method whatsoever, wherein said method comprises:
 a. Preparing a respective required quantity of a longitudinal, continuous Tensile Reinforcement Member ( 30 ), made of steel and having a Bottom End Fitting ( 51 ) designed to engage a respective Bottom Anchoring Apparatus ( 50 ), said Bottom End Fitting ( 51 ) being sufficiently small to pass through the respective top Inlet Opening ( 16 ) and through the narrowest part of the internal cavity of respective Hollow Primary Element ( 11 );   b. Preparing a respective required quantity of Top Tensioning Apparatus ( 60 ), each tailored to fit the respective typical existing top flange ( 15 ) or another existing connecting apparatus near top Inlet Opening ( 16 ) of the respective Hollow Primary Element ( 11 ), and constructed in a way that would not obstruct the insertion of the Tensile Reinforcement Member ( 30 ) into said respective Hollow Primary Element ( 11 ), and if applicable: would also facilitate the handling (namely insertion and retracting) of an Inserted Hosepipe ( 22 );   c. Inserting each of said Tensile Reinforcement Member ( 30 ) into the respective Hollow Primary Element ( 11 ), until its respective Bottom End Fitting ( 51 ) reaches the bottom of the respective Primary Element ( 11 ), and its top end is suspended from said Top Tensioning Apparatus ( 60 );   d. Installing and fixing the complete Bottom Anchoring Apparatus ( 50 ) between the bottom part of the respective Hollow Primary Element ( 11 ) and the Bottom End Fitting ( 51 ) of the respective Tensile Reinforcement Member ( 30 );   e. Applying an axial pretension of predetermined magnitude to said respective Tensile Reinforcement Member ( 30 ), through said Top Tensioning Apparatus ( 60 );   f. Filling the entire internal cavity of said respective Hollow Primary Element ( 11 ), or any part thereof as prescribed by the structural designer, with cement-based non-shrink grout.   
     
     
         11 . A method according to  claim 10 , wherein the tensioning means in said Top Tensioning Apparatus ( 60 ) comprises a conventional turnbuckle ( 61 ). 
     
     
         12 . A method according to  claim 10 , wherein the tensioning means in said Top Tensioning Apparatus ( 60 ) comprises a threaded rod ( 62 ) passing, substantially vertically, through a rigid top cover plate of Top Tensioning Apparatus ( 60 ), whereby the tensioning is applied by tightening of a top Tensioning Nut ( 63 ). 
     
     
         13 . A method according to  claim 10 , wherein said Tensile Reinforcement Member ( 30 ) is made of a plurality of long steel Rods ( 31 ) all of which having substantially equal cross-section, each of said Rods ( 31 ) having threaded end portions ( 34 ,  35 ) at both its ends, a plurality of Threaded Couplers ( 81 ) equipped with matching internal threads, and a Bottom End Fitting ( 51 ) equipped with matching internal thread as well, and wherein the process of installing said Tensile Reinforcement Member ( 30 ) starts with threading said Bottom End Fitting ( 51 ) onto the bottom-most of said steel Rods ( 31 ), then all said steel Rods ( 31 ) are sequentially coupled to each other, through said Threaded Couplers ( 81 ), during the process of inserting the Tensile Reinforcement Member ( 30 ) into the respective Hollow Primary Element ( 11 ). 
     
     
         14 . A method according to  claim 10 , wherein said Tensile Reinforcement Member ( 30 ) is made of a plurality of long steel Rods ( 31  through  33 ) made in several different cross-sectional dimensions, each of said Rods ( 31  through  33 ) having threaded end portions ( 34  through  39 ) at both its ends, a plurality of Threaded Couplers of several matching sizes ( 81 ,  82 ) equipped with matching internal threads, and a Bottom End Fitting ( 51 ) equipped with internal thread matching the bottom thread ( 39 ) of the bottom-most Rod. The number of Rods ( 31  through  33 ) may be larger than the number of different cross-sectional dimensions, such that a plurality of said rods may be of similar cross-section. Rods ( 31  through  33 ) make up a complete Tensile Reinforcement Member ( 30 ) such that its bottom portion is made of the largest cross-section Rods ( 33 ), and the cross-sections are stepping down in certain designed step-down coupling locations, wherein the top-end thread ( 36 ,  38  respectively) of the lower joining Rod ( 32 ,  33  respectively) is made smaller than the typical size thread ( 37 ,  39  respectively) of the respective Rod, so as to match the smaller size thread of the joining Coupler ( 81 ,  82  respectively), which in turn matches the thread ( 35 ,  37  respectively) of the upper joining Rod ( 31 ,  32  respectively), and wherein the process of installing said Tensile Reinforcement Member ( 30 ) starts with threading said Bottom End Fitting ( 51 ) onto the bottom-most of said steel Rods ( 33 ), then all said steel Rods ( 33  through  31 ) are sequentially coupled to each other, through said Threaded Couplers ( 82 ,  81 ), during the process of inserting the Tensile Reinforcement Member ( 30 ) into the respective Hollow Primary Element ( 11 ). 
     
     
         15 . A method according to  claim 10 , wherein said Tensile Reinforcement Member ( 30 ) is made of a single continuous Steel Wire Strand or Wire Rope, of uniform cross-section throughout its length, and is equipped with a Bottom End Fitting ( 51 ) engineered and mounted onto its bottom end according to any common practice known in the wire rope industry. 
     
     
         16 . A method according to  claim 10 , wherein said Tensile Reinforcement Member ( 30 ) is made of several segments of a Steel Wire Strand or Wire Rope ( 41  through  43 ), each made with a different cross-section, the bottom, thickest segment ( 43 ) is equipped with a Bottom End Fitting ( 51 ) engineered and mounted onto its bottom end according to any common practice known in the wire rope industry, and the other segments ( 42 ,  41 ) being coupled with each other and with the thickest segment ( 43 ) in a cross-sectional stepping down sequence, with splicing means ( 71 ,  72 ) based on any common practice known in the wire rope industry, so as to make up a complete Tensile Reinforcement Member ( 30 ). 
     
     
         17 . A method according to  claim 10 , wherein said Tensile Reinforcement Member ( 30 ) is made of a single continuous Steel Wire Strand, the cross-section of which consists several layers of wires arranged in concentric circles, said Tensile Reinforcement Member ( 30 ) being divided into a plurality of segments ( 141  through  144 ), the cross-sectional dimensions of said segments stepping-down respectively, said stepping-down of the Wire Strand's cross-sectional dimensions is obtained by peeling off a layer of the wires at each stepping down point, such that the cross-section of the bottom-most segment is equal to the Wire Strand's original cross-section, and the upper-most segment has the largest number of wire layers peeled off, and wherein said Tensile Reinforcement Member ( 30 ) further including a Bottom End Fitting ( 51 ) engineered and mounted onto the bottom end of its bottom segment ( 144 ) according to any common practice known in the wire strand industry. 
     
     
         18 . A method according to  claim 17 , wherein said Tensile Reinforcement Member ( 30 ) further includes protecting metal sleeves ( 149 ) of appropriate dimensions, fitted and crimped onto the Wire Strand's cross-sectional step-down points, so as to prevent undesired local deterioration of the Strand's structure at these locations during winding and handling. 
     
     
         19 . A method according to  claim 10 , wherein the longitudinal axes of all or part of the Hollow Primary Elements ( 11 ) of the existing structure have a breaking (turning) point at a certain intermediate location along their height, and said method includes the utilization of sufficient number of Restrainer ( 90 ), each being mounted onto a respective Hollow Primary Element ( 11 ) at a location close to said axial breaking point, after cutting or drilling an appropriate small opening through the wall of the respective Hollow Primary Element ( 11 ) at said location, each said Restrainer ( 90 ) being shaped and sized so as to maintain the axis of the Tensile Reinforcement Member ( 30 ) substantially concentric with that of the respective Hollow Primary Element ( 11 ). 
     
     
         20 . A method according to  claim 19 , wherein said Restrainer ( 90 ) comprises an Insert ( 150 ) inserted into the respective Hollow Primary Element ( 11 ) through a hole ( 160 ) drilled in its wall, Insert ( 150 ) being designed to stay permanently within the reinforced structure, and further comprises temporary supporting and fastening means, designed to firmly hold Insert ( 150 ) in place during the grout-filling process, all of said temporary supporting and fastening means being mounted on the exterior of the respective Hollow Primary Element ( 11 ) thus being removable and reusable; the length of insert  150  determined so as to restrain Tensile Reinforcement Member ( 41  in  FIGS. 20 ,  21 ) in the designed, substantially concentric location, its free end shaped with an alcove matching the cross-section of Tensile Reinforcement Member ( 41 ), and its rear end equipped with a threaded bore ( 158 ) so as to facilitate connection to said temporary supporting and fastening means by a removable bolt ( 155 ). 
     
     
         21 . A method according to  claim 20 , wherein said temporary supporting and fastening means comprise a clamping device fitted to the cross-section of Hollow Primary Element ( 11 ), made commonly of 2 parts ( 151 ,  152 ), bolted to each other with bolts ( 153 ) and nuts ( 154 ), one respective part of the clamp ( 151 ) having a drilled hole with a location and size matching those of said threaded bore ( 158 ) in Insert ( 150 ), and a bolt ( 155 ) which secures Insert ( 150 ) onto said clamp ( 151 ). 
     
     
         22 . A method according to  claim 10 , wherein the bottom end of said existing Hollow Primary Element ( 11 ) is fitted with a flat base flange ( 13 ) leaving an opening at its bottom, wherein a certain a deliberate Vertical Gap exists between the bottom surface of Flange ( 13 ) and the concrete foundation, wherein said Bottom Anchoring Apparatus ( 50 ) is designed as a simple, monolithic Beam ( 180 ) with a height not exceeding said Vertical Gap and a length sufficiently larger than the bottom opening in Flange ( 13 ), and wherein said Bottom End Fitting ( 51 ) is shaped uniquely as a Fitting ( 181 ) equipped with a bore substantially transverse to its longitudinal axis, shaped and dimensioned to facilitate the passage of Beam ( 180 ) there through, with good dimensional fit there between. 
     
     
         23 . A method according to  claim 10 , wherein the bottom end of said existing Hollow Primary Element ( 11 ) is fitted with a flat base flange ( 13 ) leaving an opening at its bottom, wherein a certain a deliberate Vertical Gap exists between the bottom surface of Flange ( 13 ) and the concrete foundation, wherein said Bottom End Fitting ( 51 ) comprises a top part ( 110 ) mounted onto the bottom end of the respective Tensile Reinforcement Member ( 44  in  FIGS. 10 ,  11  &  12 ), and heaving a substantially vertical threaded bore at its bottom, and a bottom part ( 111 ) which is a matching bolt, possibly having a specially shaped head, and wherein said Bottom Anchoring Apparatus ( 50 ) comprises a longitudinally & vertically split beam consisting two parts ( 112 ,  113 ) which may be identical or differ in shape, each containing a shaped groove, such that when the beam consisting the two parts ( 112 ,  113 ) is assembled, it snugly houses the head-part of bolt ( 111 ); the height of each beam part ( 112 ,  113 ) not exceeding said Vertical Gap, its length being sufficiently larger than the bottom opening in Flange ( 13 ), and the two beam parts ( 112 ,  113 ) being secured to each other after assembly with bolts ( 114 ) and nuts ( 115 ). 
     
     
         24 . A method according to  claim 10 , wherein the bottom end of said existing Hollow Primary Element ( 11 ) is fitted with a flat base flange ( 13 ) leaving a sufficiently large opening at its bottom, wherein a certain a deliberate Vertical Gap exists between the bottom surface of Flange ( 13 ) and the concrete foundation, wherein said Bottom End Fitting ( 51 ) is shaped as a Fitting ( 120 ) having two parallel flat faces on both its sides and a through-passing smooth bore with an axis substantially perpendicular to said two parallel flat faces and to the axis of the Tensile Reinforcement Member ( 44  in  FIGS. 13 ,  14  &  15 ), and wherein said Bottom Anchoring Apparatus ( 50 ) comprises two substantially identical beams ( 121 ) clamping End Fitting ( 120 ) there between, each of said beams ( 121 ) being made of a steel plate positioned vertically, having a transverse through-passing smooth bore matching in size said bore of said End Fitting ( 120 ), and shaped such that its central portion may be somewhat higher than said Vertical Gap, said Bottom Anchoring Apparatus further comprising a relatively thick Connecting Pin ( 122 ) dimensioned to sustain the expected shear loads and long enough to secure both beams ( 121 ) onto End Fitting ( 120 ), machined smooth along its central portion and having smaller diameter threads on both ends, so as to facilitate tightening with one or two nuts ( 123 ) and large washers ( 124 ) that are larger than said smooth bores. 
     
     
         25 . A method according  claim 24 , wherein said relatively thick Connecting Pin ( 122 ) does not have said smaller diameter threads at its ends, and said clamping of said End Fitting ( 120 ) between said two plate beams ( 121 ) is secured by separate, at least two long bolts, passing transversely through both said plate beams ( 121 ) without contacting said End Fitting ( 120 ), such that tightening said separate long bolts ensures that both plate beams ( 121 ) tightly abut said two parallel flat faces on both sides of End Fitting ( 120 ), while said Connecting Pin ( 122 ) is positioned in said through-passing smooth bores of said End Fitting ( 120 ) and of both said plate beams ( 121 ). 
     
     
         26 . A method according to  claim 10 , wherein the bottom end of said existing Hollow Primary Element ( 11 ) does not include any opening (or wherein a designer's choice is not to utilize such existing opening) wherein said Bottom Anchoring Apparatus ( 50 ) is designed as a simple Beam ( 132 ), passing transversely through said existing Hollow Primary Element ( 11 ), after cutting on site two openings in its walls in appropriate sizes and locations, and optional reinforcing of the cut openings by welded plates ( 133 ,  134 ), in one or more layers, may be utilized such that, while the field cuttings of said Primary Element ( 11 ) might be rough and the resulting openings too large, said reinforcing plated ( 133 ,  134 ) may have shop-machined openings, matching the cross-sectional shape of Beam ( 132 ), thus ensuring a tight fit there between, and wherein said Bottom End Fitting ( 51 ) of the Tensile Reinforcement Member ( 44  in  FIGS. 16 ,  17  &  18 ) is shaped uniquely as a Fitting  131  equipped with a transverse bore shaped and dimensioned to facilitate the passage of beam ( 132 ) there through, with a good geometric fit there between. 
     
     
         27 . A method according to  claim 10 , wherein said Tensile Reinforcement Member ( 30 ) is made of a combination of steel rods and wire strands or wire ropes, in various segments, spliced together so as to make up a complete Tensile Reinforcement Member ( 30 ) in the required length. 
     
     
         28 . A method according to  claim 10 , wherein the tensile load bearing capacity of the existing anchoring system, at the bottom of any Primary Element ( 11 ), is also reinforced by any procedure commonly practiced in the art, such as welding appropriate, substantially horizontal steel plates ( 204 ), having a required number of holes for additional anchoring bolts ( 200 ), onto the bottom end of said Primary Element ( 11 ), and drilling into the concrete foundation and installing with the utilization of appropriate epoxy resin ( 201 ) or the like, a required number of said additional anchor bolts ( 200 ), tightening the nuts ( 203 ) of said additional anchor bolts ( 200 ) after said resin ( 201 ) has cured, and possibly encasing the entire reinforced base in a protective mass of non-shrink concrete ( 202 ). 
     
     
         29 . A method according to  claim 10 , wherein the entire reinforcement of the structure further includes improving the load bearing capacity of secondary elements, namely certain lattice brace members of the structure, by any procedure commonly practiced in the art, such as the replacement of said certain lattice brace members of a bolted Existing Structure ( 10 ) with new brace members having larger cross-sectional area, and/or other improved properties.