MULTIPLE ABUTMENT STRUCTURES FOR REDUCED DEFLECTION

Abstract

ABSTRACT The present invention relates to multiple abutment structures 9 for reduced deflection, specifically focusing on the abutment 2 structures that enhance the stability of the approach embankment 4 and bridge abutment 2. More particularly, the present invention features multiple abutments 9 spaced depending on the vehicular load 6 within the approach embankment 4 that integrates with the approach slab 3 to effectively distribute lateral vehicular loads 7, reducing deflection and improving resistance to lateral forces. The said abutments 9 can be arranged in various configurations, including independent placements that offer construction flexibility. Predominantly, the present invention is beneficial in flood-prone areas, as it maintains access to the bridge even if parts of the approach embankment 4 are eroded. Additionally, it minimizes the frequency of maintenance and replacement needs of the backfill, providing a sustainable modern bridge infrastructure, ultimately contributing to enhanced safety and longevity of transportation networks.

Specification

Description:MULTIPLE ABUTMENT STRUCTURES FOR REDUCED DEFLECTION

FIELD OF THE INVENTION
[001] The present invention relates to structures that supports the bridge, more particularly the approach embankment of the bridge.

BACKGROUND OF THE INVENTION
[002] Background description includes information that may be useful in understanding the present invention.

[003] Bridge abutments are vital structural elements that support the ends of a bridge, connecting it to the ground. They play a critical role in the overall stability and safety of bridge structures. Their primary role is to bear the weight of the bridge and support the backfill of the approach embankment distribute loads safely to the foundation and underlying soil. Understanding their design, types, and functions is crucial in civil engineering and bridge construction that directly impacts the longevity and functionality of this vital transportation infrastructure.

[004] The challenges posed by approach embankments are also significant in bridge engineering, particularly concerning their stability and maintenance, as the lateral loads of the vehicles can lead to issues such as displacement, compression, and settlement. Over time, this often results in uneven settling and the formation of bumps or "camel backs," which can create hazardous conditions for drivers. Natural forces like rain or floodwaters can exacerbate these problems by eroding the embankment and increasing the risk of washouts. In flood-prone areas, severe damage can cut off access to towns and villages, leading to substantial economic and social impacts, as residents may face long detours or become stranded. Additionally, maintaining approach embankments requires regular upkeep, which can be costly, and in many cases, extensive repairs or replacements are necessary, causing significant traffic disruptions. Properly designed abutments not only support the physical structure of the bridge but also contribute to its resilience against settlements and environmental challenges.

[005] Settlement refers to the gradual sinking or downward movement of a structure, such as a approach embankment, due to the compression or shifting of the soil beneath it. This phenomenon can occur for several reasons, including soil compression under the weight of the structure and vehicular loads, the nature of the underlying soil particularly in clay or loose sand, which are prone to shifting and changes in moisture content that can cause soil expansion or contraction. Additionally, nearby construction activities or excavation can destabilize the ground, exacerbating settlement issues.

[006] The following papers of researchers are attempting to unravel the problem as to why the Approach slab which was designed to protect or make sure that bump does not form at the junction between the pavement and the bridge end up failing. One of the reasons for the failure could be that the horizontal component of the vertical load is acting on the abutment and is constantly deflecting the abutment, hence displacing the soil i.e. the back-fill in the approach embankment.

[007] Known in the art is Amr Abdelrahman, Mohammed Tawfik, A.El-Saify, (2018) which discloses that the settlement of the approach embankment is attributed to the time-dependent deformations of the soft sub-soil. Approach slabs also do not prevent the approach embankments from settlement.

[008] Known in the art is Carlos Zanuy and Luis Albajar, (2013) reveals that, in the long-term, the approach slab is deficient, requiring high maintenance or repair cost. Their study showed that a significant number of slabs could be classified as severely cracked or even broken, and the fatigue damage caused by heavy trucks was shown to be the main factor for the failing of the approach slab. Surface cracks have been reported to be one of the main reasons causing the deterioration of approach slabs.

[009] Also known in the art is Hj. Mohd Idrus B, Hj.Mohd Masirin and Rasimah Bt Md Zain. (2013) studied the differential settlement between bridges and pavement to understand the behaviour of soils and bridge structures; they disclosed that the introduction of approach slabs by many engineers has reduced some of the problems at the interface sections but only for a short period of time. Their study revealed that the differential settlements are common when road and bridge meet or interface. The difference in rigidity played an important element. However, different structural rigidity of different materials will react differently when subjected to a certain loading.

[010] Kun Zhang1, Di Feng1 and Zhikui Wang2 Zhang K, Feng D and Wang Z (2023) illustrated that the seasonal rains can cause havoc to some embankments where the clay content is more; in some instances, an entire embankment has collapsed causing a loss in millions. Their studies also showed that the shear strength of the soil decreases with the increase in immersion time of the embankment.

[011] Qiming Chen and Murad Y Abu-Farsakh (2014) explained that the ride quality of bridge approaches slabs still needs to be resolved. The complaints usually involve a ''bump'' that motorists feel when they drive on or off bridges. This problem is commonly referred to as the bump at the end of the bridge, mainly resulting from the differential settlement of the concrete approach slab relative to the bridge deck. It poses a safety hazard as well as being disruptive to motorists. Field observations indicated that either faulting at the road way pavement /approach slab joint (R/S joint) or a sudden change in the slope gradient at the approach slab/bridge deck joint (S/D joint) causes this bump.

[012] Randy D. Martin and Thomas H.K.King, (2013) revealed in his art that although the primary cause of approach slab problems is largely geotechnical in nature, the structural design of the approach slab is important to ensure that it performs its functions to an acceptable level over its service life and that said service life is reasonably long. Currently, design guides are not available, requiring practicing engineers and state departments of transportation to rely upon experience and frequent maintenance of the approach slabs.

[013] Furthermore, Wei CAO, Long XU, Yifan HU, Yanhui LU and Zhenzhen QUAN. (2022); the authors were of the view that the during the construction of the subgrade and pavement in the settlement section at the junction of road and bridge, uneven settlement of subgrade, irregular deformation of pavement, unevenness of pavement, cracking and other phenomena are more likely to occur, thereby reducing the smoothness of the pavement, resulting in bridge-head, bump, thereby impacting driving safety, stability and comfort.

[014] CN219772685 discloses Bridge abutment structure for bridge construction that pertains to anti settling mechanism and anti-seepage mechanism using filters. Further, CN109629455B also discloses the construction method for reconstructing bridge of highway

[015] US8925132B1 reveals bridge structures and constructional method of bridges and in particular to steel span bridges and the bracing of girders.

[016] The aforementioned prior art discloses various construction methods but fails to address the underlying causes of deflection in abutments and approach slabs. While these methods provide insights into structural design, they do not adequately investigate the factors contributing to deflection.

[017] Conventionally, the abutments do not provide support for the pavement (road). Moreover, in the event of flooding, the entire embankment on either side of the bridge, which is typically composed of soil, gets washed away.

[018] Some of the work conducted by scientists and researchers indicates that ongoing investigations aim to explore the failure of approach slabs and embankments due to various factors. These conventional studies have primarily focused on soil failure, concluding that the deterioration of the approach slab in front of the abutment is linked to multiple underlying causes. Ultimately, well-designed approach embankments enhance the safety, stability functionality of transportation networks, facilitating efficient traffic flow and access.

[019] Hence, there is a need for constructing retaining structures that exhibit reduced deflection, lower initial manufacturing costs, minimized total ownership costs, decreased inspection and maintenance expenses, reduced negative environmental impact, and simplified load-bearing designs. These attributes are essential for improving the economic feasibility and sustainability of abutment structures.

OBJECTS OF THE INVENTION
[020] Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:

[021] The principal object of the present invention is to provide multiple abutment structures in the approach embankment for reduced deflection of the Bridge abutment.

[022] Another object of the present invention is to provide reduced deflection of bridge abutment by distributing the lateral force of vehicular load.

[023] Another object of the present invention is to reduce the bump creation due to the vehicular load.

[024] Another object of the present invention is to minimize the replacement of approach embankments.

[025] Another object of the present invention is to have continual access to the bridge even when the backfill is washed out.

[026] Another object of the present invention is avoiding the replacement of back -fills in the approach embankment.

[027] Yet another object of the present invention is to provide independent multiple abutments on either side of the box culvert.



SUMMARY OF THE INVENTION
[028] The present invention aims to provide multiple abutment structures featured for reduced deflection by installing a plurality of abutments spaced within the approach embankment, allowing lateral vehicular loads to be distributed effectively. The spacing between adjacent abutments is optimized to ensure maximum load distribution and minimize stress concentrations. Additionally, the multiple abutment structure is intended for integration with approach slabs to provide a smooth and stable transition for vehicles entering and exiting the bridge. This system is also adaptable for use in flood-prone areas, maintaining access to the bridge even if portions of the approach embankment are compromised.

[029] According to an aspect of the present invention, a multiple abutment structures for reduced deflection comprising: at least one vertical structure structured within an approach embankment of the bridge; wherein the said vertical structures are a plurality of abutments constructed in series between the base foundation and the pavement of the approach embankment; characterised in that lateral vehicular load is distributed across the said abutments, and the said abutments are of sequentially increasing heights towards the bridge.

[030] It is another aspect of the present invention, wherein spacing between the said abutments that are adjacent depends on the vehicular load.

[031] It is another aspect of the present invention, wherein the spacing between the said abutments is flexible and is not limited to equidistant arrangements.

[032] It is another aspect of the present invention, wherein the spacing between the said abutments depends on location and function of the bridge.

[033] It is another aspect of the present invention, wherein the said abutments closer to the bridge are intended for integration with approach slab supporting the pavement.

[034] It is another aspect of the present invention, wherein each of the said abutments is constructed from reinforced concrete and the like.

[035] It is another aspect of the present invention, wherein the said structure allows access to the bridge even if portions of the approach embankment are battered.

[036] It is another aspect of the present invention, wherein allows the independent placement of abutments alongside other structural elements but not only limited to box culverts.

[037] It is another aspect of the present invention, wherein the percentage improvement of in reduced deflection ranges from 80% to 93%.

[038] It is another aspect of the present invention, a method for reducing the deflection in multiple abutment structures comprising: evaluating measurements and analysing vehicular load; erecting vertical structures that are a plurality of abutments in series between the base foundation and the pavement of the approach embankment which distributes the lateral vehicular load across the said abutments, designing the said abutments of sequentially increasing heights towards the bridge within in approach embankment.

[039] It is another aspect of the present invention, wherein the spacing between the said abutments of the method is flexible and is not limited to equidistant arrangements.

It is another aspect of the present invention, wherein the spacing between the said abutments of the method depends on location and function of the bridge.

[040] It is another aspect of the present invention, wherein the said abutments of the method are constructed from reinforced cement concrete and the like.

[041] It is another aspect of the present invention, wherein the method allows for independent placement of abutments alongside other structural elements but not only limited to box culverts.

[042] It is another aspect of the present invention, wherein the percentage change in reduced deflection by implementing this method ranges from 80% to 93%.

BRIEF DESCRIPTION OF THE DRAWINGS
[043] Reference made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in the context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
[044] FIG. 1 illustrates the isometric view of the multiple abutments according to the present invention.
[045] FIG. 2 illustrates the schematic representation of the typical Bridge Abutment and the approach embankment according to the present invention.
[046] FIG. 3 illustrates the loading for 4m high abutment according to the present invention
[047] FIG. 4 illustrates the loading for 8 abutments according to the present invention
[048] FIG. 5 illustrates the loading for 0.5 m height of abutment according to the present invention
[049] FIG. 6 illustrates the loading for 0.5m for 1m height of abutment according to the present invention
[050] FIG. 7 illustrates the loading for 0.5m for a 1.5m height of abutment according to the present invention
[051] FIG. 8 illustrates the loading for 0.5m for a 2m height of abutment according to the present invention
[052] FIG. 9 illustrates the loading for 0.5m for a 2.5 m height of abutment according to the present invention
[053] FIG. 10 illustrates the loading for 0.5m for a 3.0 m height of abutment according to the present invention
[054] FIG. 11 illustrates the loading for 0.5m for a 3.5 m height of abutment according to the present invention
[055] FIG. 12 illustrates the loading for 0.5m for a 4.0 m height of abutment according to the present invention
DETAILED DESCRIPTION OF INVENTION
[056] The subsequent segments will detail various examples and embodiments of the invention, emphasizing that the scope of the present invention extends beyond any specific instance presented. These details are intended for illustrative purposes only and should not be interpreted as restrictions on the invention's overall capitalizing breadth. In the accompanying figures, similar components are denoted by matching reference numerals. To maintain conciseness, the comprehensive description for one view is not repeated for others, as it is understood that the same description applies to all views.

[057] Various factors were considered for the settlement and failure of the approach slab, yet the impact of lateral forces from vehicular loads was often overlooked. This oversight contributed to an incomplete understanding of the underlying issues affecting the stability and performance of the approach slab. Addressing the influence of lateral forces, specifically the component PSinθ of the vehicular load P, is crucial for developing more effective design solutions and mitigating potential failures in bridge structures. Understanding how these lateral forces contribute to issues such as bumps and instability is essential for ensuring the overall safety and performance of the bridge.

[058] The present invention seeks to enhance bridge stability through a specially designed abutment structure aimed at reducing deflection by including the lateral vehicular load into consideration. This structure consists of multiple abutments 9 in series which are strategically spaced within the approach embankment 4, that allows for effective distribution of lateral vehicular loads. The multiple abutments 9 are built in sequentially increasing heights towards the bridge 1. The optimization of spacing between adjacent abutments is crucial for maximizing load distribution and minimizing stress concentrations, wherein the spacing between adjacent abutments 8 is determined by the vehicular load 6 as well as the intended purpose and location of the bridge 1. Furthermore, the abutment structure is designed for seamless integration with approach slabs 3, ensuring a smooth and stable transition for vehicles accessing the bridge. For example, in the case of a bridge spanning a water body, the spacing between multiple abutments may be less than 6 meters to effectively counter lateral vehicular loads and provide support for the reinforced concrete pavement of the approach embankment. Specifically, near bridges crossing water bodies, abutments can be constructed at intervals of 5 to 6 meters, designed to support the pavement with a reinforced cement concrete slab on top. This configuration ensures that even if the surrounding soil is eroded or approach embankment is battered or washed away, accessibility to the bridge can still be maintained. Generally, the distance between abutments remains flexible, allowing for adjustments based on the load from vehicular traffic. This innovative system is also suitable for flood-prone regions, ensuring continued access to the bridge even if sections of the approach embankment are compromised.

[059] The approach embankment 4 is continually subjected to lateral forces from vehicular loads, which apply pressure on the abutment 2. This can lead to deflection, ultimately causing failures in both the approach slab and the embankment itself. To address these challenges, incorporating multiple abutments 9 in the design of the approach embankment 4 presents a viable solution. By distributing loads more evenly across several abutments 9, the stress on each individual abutment can be reduced, which minimizes deflection and enhances the overall resilience of the embankment.

[060] Furthermore, the use of multiple abutments 9 can provide more robust support for the approach slab 3, significantly extending its lifespan. This arrangement not only ensures greater stability under the constant forces exerted by traffic but also facilitates a safer transition for vehicles as they enter and exit the bridge. Ultimately, this proactive design strategy can lead to reduced maintenance costs and improved safety for road users, reinforcing the importance of thoughtful engineering in bridge construction.

[061] The abutments are designed as cantilevers, featuring vertical support structures that extend from the base foundation to the pavement. This design enhances stability by providing additional resistance against lateral loads, which are generated by vehicular traffic and environmental forces. These abutments help distribute these lateral stresses more effectively, reducing the risk of deflection of the Bridge abutment and failure of the approach slab 3. By reinforcing the structure in this way, cantilevered abutments contribute to improved overall stability and durability, ensuring safer transitions for vehicles and prolonging the lifespan of the bridge infrastructure. While this text often refers to abutments specifically in relation to bridge and retaining structures, those with expertise in the field will understand that the structures and methods described can also be applied to abutments serving various other functions of constructions.

[062] Fig 1 of the present invention showcases an isometric view of multiple abutments 9, each strategically positioned at specific intervals to effectively distribute the transitional vehicular load 6. This arrangement of plurality of abutment enhances the stability and reduces the stress on individual abutments, ensuring a more resilient structure. By sharing the load across several points, the design aims to improve overall performance and longevity of the infrastructure, facilitating safer transitions for vehicles as they navigate the bridge approach. A sample dataset was gathered from the toll gate to calculate the cumulative vehicle load, as detailed in the report titled "Request for Proposal for Independent Engineer during Operation & Maintenance," published by the National Highways Authority of India in 2018. This data is crucial for understanding traffic patterns and vehicle volumes, which can inform maintenance and operational strategies for the highway infrastructure Referring to this data, various embodiments as mentioned further are being considered for studying and analysing the strength of vehicular load.

[063] The vehicles pass on the approach embankment 4 on either side of the bridge that is constructed over a water body, or another road (also called a Flyover). The approach embankment 4 is a raised alignment structure that connects a roadway to a bridge, facilitating load distribution and a smooth transition for vehicles as they enter or exit the bridge. Approach slab 3 is also a critical component of bridge design, serving as the transition surface between the bridge deck and the approach roadway. Typically constructed from reinforced cement concrete, the approach slab offers a smooth and stable surface for vehicles as they transition onto and off the bridge. This reinforced cement concrete slab, which rests on the abutment at one end and on the underlying soil at the other, is generally 300 mm thick and spans a length of 3 meters. The abutment 2 is structured adjacent to the bridge as retaining support between the pavement and the foundation. It acts as supporting structure to the approach slab 3 as well as approach embankment 4. The abutment 2 serves as a critical connection point, transferring the loads from the bridge to the ground while also retaining the earth behind it. By ensuring proper load distribution, abutments help maintain the integrity of both the bridge and the surrounding infrastructure, facilitating safe and efficient vehicle passage.

[064] The 'P' denoted as 6 is a vehicular load acting on the approach embankment according to the figure 2 of the present invention. The horizontal component of the Vehicular load 6 is the lateral load 7. As the angle of inclination increases the lateral load increases. The Morth ( Ministry of Road Transport and Highways) has a specified inclinations for Highways for different terrain. P is the load of the vehicle or vehicles travelling towards the Bridge. The below vector diagram depicts PSinθ as the lateral load of the Vehicles. The horizontal component herein acts as horizontal force which is PSinθ.
P=√((P〖Cosθ)〗^2+(P) 〖Sinθ)〗^2

[065] 'θ' is the gradient denoted as 8 which is an angle of inclination of the approach embankment, the angle of inclination 8 is governed by the (Ministry of Road Transport and Highways) for different terrains. As the vehicle passes by approach embankment, the horizontal force component of vehicular load 6 acts perpendicular to the structured abutment resulting in a lateral load 7 of the vehicle PSinθ whereas the vertical force component PCosθ acts towards the ground.

[066] During the vehicular weight calculation, a variety of vehicle types are taken into account, including cars, light commercial vehicles (LCVs), buses, trucks, medium and heavy vehicles (MAVs), oversized vehicles, and three-axle trucks. This comprehensive approach ensures that the calculations accurately reflect the diverse range of vehicles using the roadway. The approximate number of Vehicles at the Toll gate for a Single trip for 'a four lane' Road is 43,556. There are approximately 43,556 vehicles per month using a particular Highway.

[067] Table 1. The vehicular weight Calculation on 4-lane Highway
S.No. Name of the vehicle No of vehicles Approximate weight of vehicle (kN) Total weight of vehicles (kN)
1 Car 4289 35 150115
2 LCV * 1399 52.5 73447.5
3 Bus 2349 180 422820
4 Truck 1566 190 297540
5 3 Axle 15127 285 4311195
6 MAV ** 18790 490 9207100
7 Over Sized *** 36 550 19,800
Total Weight of the Vehicles 1.44,82,018

* LCV- Light Commercial Vehicle
** MAV- Multi-Axle Vehicle
*** Over Sized Vehicle- To be capped at 550kN as per Annexure -B of No. RT11028/11/2017-MVL; Ministry of Road Transport & Highways (Transport Division).

[068] Considering the approximate total weight of vehicles using a 4-lane road of 16.6m. is 14482018kN for a particular month on a flyover having the height of the abutment as 4m and for Plain and Ruling Terrain assuming an exceptional gradient of the approach embankment as 6.7% i.e. angle of the gradient as 3.8331°. Some of the gradients 'θ' are considered as per IRC: SP:23-1993, Table 1 and MORTH Pocket Book for Highway Engineers Table 4.14.
As observed from the Table 1, considering the approximate vehicle load to be approximately 14482018 kN per month (=14882018 )/30 = 482734 per day = 4382734/24 = 20114 kN/hr. i.e P =20114 kN/hr. For a gradient of the approach abutment as 3.8331°, the lateral force PSin(3.8331°) on the Abutment is 1344.62351 kN/hour.

[069] The abutment 2 herein are referred as cantilevers that are structured vertically with fixed end denoted as A and its free ends of the abutment or cantilever denoted as B as shown in Fig. 3 . The Length 'L' is the height of the abutment. L is the height between fixed end 'A' and free end 'B'. The cantilever or abutment (2) carries a uniformly distributed load over entire length. The free ends of the abutment 'B' is deflected alongside of the top of the approach embankment (4). The moment of Inertia for the abutment (2) is I=(b×d^3)/12 considering for 1metre breadth. The Moment of Inertia is the same for simply supported, fixed or cantilever.
wherein 'b' is the breadth of the cantilever and 'd' is the depth of the cantilever.
YB represent deflection for abutment (2) or cantilever.

[070] As depicted in Fig.3 illustrating the loading for 4m high abutment. Considering installing in the Highway to be a 4 lane of 16.6m, the load per /m = 1344.62351/16.6 = 81.00142 kN/m/hr.
[071] Assuming the abutment to be a cantilever of 0.6m depth and 4m height.
The moment of Inertia of the cantilever considering breadth(b) as 1m and depth (d) as 0.6m
I=(b×d^3)/12=(1.0×〖0.6〗^3)/12= 0.018 m4.
considering the grade of concrete as M30 grade of Concrete Ec=5000√fck =27386.13N/mm2=27386.13x106 N/m2

[072] As per table 2 of IS (Indian Standard) 456:2000. The M30 is the grade of concrete. It is compressive strength of a 150 mm cube of concrete at 28 days of curing which is 30 N/mm2. As per clause 6.23 of IS 456:2000, the modulus of concrete is Ec=5000√fck; where fck is the compressive strength of concrete which is 30 N/mm2 for M30.
[073] The approximate ratio of M30 concrete is 1 cement:0.75sand:1.5aggregate in apportion for 1cum of concrete mixed together with a particular quantity water which is called water cement ratio which is determined by conducting tests.
[074] For the abutment acting as a cantilever of L=4 m., the deflection of the abutment with the uniformly distributed load of 81.00142 kN/m/hr and for a gradient of 3.8331° only due to the horizontal component of the traffic load is
〖 y〗_B=(wL^4)/(8E_c I)=(81.00142×1000×4^4)/(8×27386.13×〖10〗^6×0.018) = 0.00526 m per hour = 5.26 mm per hour.

[075] The abutments herein are referred as cantilevers that are structured vertically with fixed end denoted as 1A to 8A and their free ends of the abutment or cantilever with free end denoted as 1B to 8B respectively. The Length 'L' is the height of the abutment. 'L' is the height between fixed end 'A' and free end 'B'. The cantilever or abutment carries a uniformly distributed load.

[076] The moment of Inertia for the abutment is I=(b×d^3)/12 considering for 1metre span wherein 'b' is the breadth of the cantilever and 'd' is the depth of the cantilever.
Y1B to Y8B represent deflections for abutments or cantilevers of different heights and loading condition.

[077] According to the preferred embodiment, in case of multiple abutments (9) as shown in figure 1, for the same approach embankment of a run (horizontal distance) of 59.7013 m and abutment of height 4m, the proposal is to have abutments of heights 0.5 m at 7.463m run, 1m height at 14.925 m run, 1.5 m height at 22.388 m run, 2 m height at 29.8506 m run, 2.5 m height at 37.3133 m run, 3m height at 44.776 m run, 3.5 m height at 52.2386 m run and 4m height at 59.7013 m run as shown in figure 4. The Lateral load on the first abutment is 0.5m. As the vehicle travels from 0.5m high abutment to 1.0m high abutment the lateral load on the 1.0m high abutment is 0.5m only. As the height of the abutments is increased by 0.5m, the lateral load acts only on 0.5m which is represented as 'a' in the drawings from figure 5 to figure 12. Various embodiments are considered for the research purpose to calculate the deflection for abutments of sequential heights and respective loads.

[078] 1. In one example, for a gradient of approach abutment as 3.8331° the lateral force PSin(3.8331°) on the Abutment is 1344.62351 kN/hour. Considering the Highway to be a 4 lane of 16.6m, the load per/m = 1344.62351/16.6 = 81.00142 kN/m.
[079] The Fig. 5 of the present invention illustrates loading for 0.5m height of abutment. Assuming the abutment to be a cantilever. of 1m breadth and 0.6 m depth and length L1= 0.5 m at 7.463 m run, the load is distributed on the entire length. The moment of Inertia of the cantilever considering breadth(b) as 1m and depth (d) as 0.6m
I=(b×d^3)/12=(1.0×〖0.6〗^3)/12= 0.018 m4.
[080] Considering the grade of concrete as M30 grade of Concrete Ec = 5000√fck = 27386.13 N/mm2=27386.13x106 N/m2 for the abutment acting as a cantilever of length L1=0.5m., the deflection of the abutment with the uniformly distributed load w= 81.00142kN/m/hr for gradient of 3.8331° only due to the horizontal component of the traffic load is y_1B=(w〖(L_1)〗^4)/(8E_c I)
(81.00142×1000×〖0.5〗^4)/(8×27386.13×〖10〗^6×0.018)
= 1.28375E-06 m per hour =1.28375E-03 mm per hour

[081] 2. In another example, as the vehicular load has passed 14.925 m run at the 1m high abutment the lateral load is effective only on the 0.5m height of the abutment.as depicted in Fig 6. Considering the load per metre of 81.00142 kN/m and assuming the abutment to be a cantilever of 0.6m depth and length L2 = 1.0 m. The moment of Inertia of the cantilever considering breadth(b) as 1m and depth (d) as 0.6m
I=(b×d^3)/12=(1.0×〖0.6〗^3)/12= 0.018 m4. considering the grade of concrete as M30 grade of Concrete Ec=5000√fck =27386.13 N/mm2 =27386.13x106 N/m2.
[082] Assuming the abutment to be a cantilever of length L2=1.0m stretches between 2A and 2B. The lateral load is considered only for (a)= 0.5m height of the abutment, the deflection of the abutment with the uniformly distributed load of w=81.00142 kN/m/hr for a gradient of 3.8331° only due to the horizontal component of the traffic load
y_2B=w/(E_(c ) I) [〖(L_2)〗^4/8-[〖(L_2-a)〗^4/8+(〖(L_2-a)〗^3×a)/6]]=
(81.00142×1000)/(27386.13×〖10〗^6×0.018) [1^4/8-[〖(1-0.5)〗^4/8+(〖(1-0.5)〗^3×0.5 )/6]]
= 0.000017545 m per hour =0.017545 m per hour.
[083] 3. In another example, as the vehicular load has passed 22.388 m run at the 1.5 m high abutment the lateral load is effective only on the 0.5 m height of the abutment. Considering the load per metre of 81.00142 kN/m and assuming the abutment to be a cantilever of 0.6 m depth and length L3 = 1.5 m. The moment of Inertia of the cantilever considering breadth(b) as 1 m and depth (d) as 0.6 m
I=(b×d^3)/12=(1.0×〖0.6〗^3)/12= 0.018 m4.
[084] Considering the grade of concrete as M30 grade of Concrete Ec=5000√fck =27386.13 N/mm2=27386.13x106 N/m2. For loading for (a)=0.5 m for a 1.5 m height of abutment as illustrated in Fig.7 Assuming the abutment to be a cantilever of length L3=1.5 m stretches between 3A and 3B. The lateral load is considered only for (a)=0.5 m height of the abutment, the deflection of the abutment with the uniformly distributed load of w=81.00142 kN/m/hr for gradient of 3.8331° only due to the horizontal component of the traffic load
y_3B=w/(E_(c ) I) [〖(L_3)〗^4/8-[〖(L_3-a)〗^4/8+(〖(L_3-a)〗^3×a)/6]]

(81.00142×1000)/(27386.13×〖10〗^6×0.018) [〖1.5〗^4/8-[〖(1.5-0.5)〗^4/8+(〖(1.5-0.5)〗^3×0.5 )/6]]

= 0.000069750 m per hour =0.06975 mm per hour.

[085] 4. In another example, as the vehicular load has passed 29.8506 m run at the 2.0 m high abutment the lateral load is effective only on the 0.5 m height of the abutment. Considering the load per metre of 81.00142 kN/m and assuming the abutment to be a cantilever of 0.6m width and length L4 = 2.0 m. The moment of Inertia of the cantilever considering breadth(b) as 1m and depth (d) as 0.6 m
I=(b×d^3)/12=(1.0×〖0.6〗^3)/12= 0.018 m4.
[086] Considering the grade of concrete as M30 grade of Concrete Ec=5000√fck = 27386.13 N/mm2= 27386.13x106 N/m2.
For loading for (a)=0.5 m for a 2.0 m height of abutment as shown in Fig.8. Assuming the abutment to be a cantilever of length L4=2.0 m spans between 4A and 4B. The lateral load is considered only for (a)= 0.5m height of the abutment, the deflection of the abutment with the uniformly distributed load of w=81.00142 kN/m/hr for a gradient of 3.8331° only due to the horizontal component of the traffic load
y_4B=w/(E_(c ) I) [〖(L_4)〗^4/8-[〖(L_4-a)〗^4/8+(〖(L_4-a)〗^3×a)/6]] =
=(81.00142×1000)/(27386.13×〖10〗^6×0.018) [〖2.0〗^4/8-[〖(2.0-0.5)〗^4/8+(〖(2.0-0.5)〗^3×0.5 )/6]]
= 0.000178441 m per hour =0.178441 mm per hour.

[087] In another example, as the vehicular load has passed 37.3133 m run at the 2.5 m high abutment the lateral load is effective only on the 0.5m height of the abutment.
Considering the load per metre of 81.00142 kN/m and assuming the abutment to be a cantilever of 0.60m depth and length L5 = 2.5 m.
The moment of Inertia of the cantilever considering breadth(b) as 1m and depth (d) as 0.6 m
I=(b×d^3)/12=(1.0×〖0.6〗^3)/12= 0.018 m4. Considering the grade of concrete as M30 grade of Concrete Ec=5000√fck =27386.13 N/mm2=27386.13x106 N/m2. For loading for (a)= 0.5 m for a 2.5 m height of abutment as shown in Fig.9.
[088] Assuming the abutment to be a cantilever of length L5=2.5 m is the height between 5A and 5B. The lateral load is considered only for (a)=0.5m height of the abutment, the deflection of the abutment with the uniformly distributed load of w= 81.00142 kN/m/hr for a gradient of 3.8331° only due to the horizontal component of the traffic load
y_5B=w/(E_(c ) I) [〖L_5〗^4/8-[〖(L_5-a)〗^4/8+(〖(L_5-a)〗^3×a)/6]]=
(81.00142×1000)/(27386.13×〖10〗^6×0.018) [〖2.5〗^4/8-[〖(2.5-0.5)〗^4/8+(〖(2.5-0.5)〗^3×0.5 )/6]]

=0.000364156 m per hour =0.364156 mm per hour.

[089] 6. In another example, as the vehicular load has passed 44.776 m run at the 3.0 m high abutment the lateral load is effective only on the 0.5 m height of the abutment.
Considering the load per metre of 81.00142 kN/m and assuming the abutment to be a cantilever of 0.6 m depth and length L6 = 3.0 m.
The moment of Inertia of the cantilever considering breadth(b) as 1m and depth (d) as 0.6 m
I=(b×d^3)/12=(1.0×〖0.6〗^3)/12= 0.018 m4. Considering the grade of concrete as M30 grade of Concrete Ec=5000√fck =27386.13 N/mm2=27386.13x106 N/m2.
For loading for (a) = 0.5m for a 3m height of abutment as shown in Fig. 10
[090] Assuming the abutment to be a cantilever of length L6=3.0 m spans between 6A and 6B. The lateral load is considered only for (a)= 0.5m height of the abutment, the deflection of the abutment with the uniformly distributed load of w=81.00142 kN/m/hr for a gradient of 3.8331° only due to the horizontal component of the traffic load
y_6B=w/(E_(c ) I) [〖L_6〗^4/8-[〖(L_6-a)〗^4/8+(〖(L_6-a)〗^3×a)/6]]

(81.00142×1000)/(27386.13×〖10〗^6×0.018 ) [〖3.0〗^4/8-[〖(3.0-0.5)〗^4/8+(〖(3.0-0.5)〗^3×0.5 )/6]]
= 0.000647437 m per hour =0.647437 mm per hour

[091] 7. In another example, as the vehicular load has passed 52.2386 m run at the 3.5 m high abutment the lateral load is effective only on the 0.5m height of the abutment.
Considering the load per metre of 81.00142 kN/m and assuming the abutment to be a cantilever of 0.6 m depth and length L7=3.5 m. The moment of Inertia of the cantilever considering breadth(b) as 1m and depth (d) as 0.6 m I=(b×d^3)/12=(1.0×〖0.6〗^3)/12= 0.018 m4. Considering the grade of concrete as M30 grade of Concrete Ec=5000√fck =27386.13 N/mm2=27386.13x106 N/m2.
For loading for (a)= 0.5m for a 3.5m height of abutment as illustrated in fig. 11

[092] Assuming the abutment to be a cantilever of length L7=3.5 m spans between 7A and 7B. The lateral load is considered only for (a)= 0.5m height of the abutment, the deflection of the abutment with the uniformly distributed load of w=81.00142kN/m/hr for a gradient of 3.8331° only due to the horizontal component of the traffic load
y_7B=w/(E_(c ) I) [〖L_7〗^4/8-[〖(L_7-a)〗^4/8+(〖(L_7-a)〗^3×a)/6]]
= (81.00142×1000)/(27386.13×〖10〗^6×0.018 ) [〖3.5〗^4/8-[〖(3.5-0.5)〗^4/8+(〖(3.5-0.5)〗^3×0.5 )/6]]

= 0.001048822 m per hour =1.048822 mm per hour

[093] 8. In yet another example, as the vehicular load has passed 59.7013 m run i.e. to the end of the approach embankment (4), for a 4.0m high abutment the lateral load is effective only on the 0.5 m height of the abutment. Considering the load per metre of 81.00142 kN/m and assuming the abutment to be a cantilever of 0.6 m width and length L8 = 4.0 m. The moment of Inertia of the cantilever considering breadth (b) as 1m and depth (d) as 0.6 m
I=(b×d^3)/12=(1.0×〖0.6〗^3)/12= 0.018 m4. Considering the grade of concrete as M30 grade of Concrete Ec=5000√fck =27386.13 N/mm2=27386.13x106 N/m2.
For loading for (a)= 0.5m for a 4m height of abutment as shown in fig. 12
[094] Assuming the abutment to be a cantilever of length L8=4.0m that stretches between 8A and 8B. The lateral load is considered only for (a)= 0.5m height of the abutment, the deflection of the abutment with the uniformly distributed load of w= 81.00142kN/m/hr for a gradient of 3.8331° only due to the horizontal component of the traffic load
y_(B_8 )=w/(E_(c ) I) [〖L_8〗^4/8-[〖(L_8-a)〗^4/8+(〖(L_8-a)〗^3×a)/6]]
= (81.00142×1000)/(27386.13×〖10〗^6×0.018 ) [〖4.0〗^4/8-[〖(4.0-0.5)〗^4/8+(〖(4.0-0.5)〗^3×0.5 )/6]]

= 0.001588851 m per hour =1.588851 mm per hour.
[095] Various embodiments of the present invention stretch a comprehensive understanding of how abutment height and loading conditions affect deflection. Table 2 recaps the details of all the deflections observed in various embodiments. This format provides a clear and concise summary of how different parameters, such as abutment height and loading conditions, affect deflection.

S.No Height of the abutment Distance of the load Depth Breadth of the Abutment Moment of Inertia Deflection of the abutment 'Y' Deflection 'Y'

L (m) a' (m) d (m) b (m) I=bd^3/12 (m/hr) ( mm/hr)
1 0.5 0.5 0.6 1 0.018 0.000001 0.00128
2 1 0.5 0.6 1 0.018 0.000018 0.01754
3 1.5 0.5 0.6 1 0.018 0.000070 0.06975
4 2 0.5 0.6 1 0.018 0.000178 0.17844
5 2.5 0.5 0.6 1 0.018 0.000364 0.36416
6 3 0.5 0.6 1 0.018 0.000647 0.64744
7 3.5 0.5 0.6 1 0.018 0.001049 1.04882
8 4 0.5 0.6 1 0.018 0.001589 1.58885


[096] The table above facilitates easy comparison and analysis of abutments with varying heights, ranging from 0.5 m to 4 m, with a lateral load distance of 0.5 m, a depth of 0.6 m, and a breadth of 1 m. The deflection of the abutments varies from 1.3E-03 mm/hr to 1.58885 mm/hr for a four-lane highway measuring 16.6 m in length. This data enables a comprehensive understanding of the factors influencing structural performance.
Maximum Arrived Deflection: 1.58885 mm/hr
Minimum Arrived Deflection: 1.283E-03 mm/hr (which is 0.0013 mm/hr)

[097] The average of all calculated deflections is approximately 0.489375mm/hr. The improvement in the performance depends on reduced deflection. The derived deflection without implementing multiple abutments is 5.11035 mm/hr and the average deflection by installing the multiple abutments is 0.489375 mm/hr.
Initial Deflection (without multiple abutments): 5.11035 mm/hr
Average Deflection (with multiple abutments): 0.489375 mm/hr

[098] Percentage change = ((0.489375−5.11035)/5.11035) × 100 = approximately 90.5% reduced deflection. This indicates a substantial reduction in deflection when multiple abutments are utilized. Specifically, this represents a percentage improvement demonstrating the significant decrease in the deflection achieved through the implementation of multiple abutments.

[099] This calculation emphasizes the effectiveness of using multiple abutments in structural designs, showcasing their role in enhancing stability and reducing deflection of the bridge abutment 1 in bridge structures This reduction in deflection helps maintain the integrity of the backfill and mitigates soil settlement, almost no bumps leading to smoother approach embankments 4.

[100] The method for reducing the deflection in abutment structures 9, comprising: evaluating measurements and analysing vehicular load; erecting a plurality of vertical structures that are abutments 9 in series between the base foundation and the pavement of the approach embankment 4 to distribute lateral vehicular load 7 across the said abutments 9 depending on the location and function or the intended purpose of the bridge1; and designing the said abutments 9 with sequentially increasing heights towards the bridge within the approach embankment 4 contributes to the construction of a sustainable bridge structure 1 and enhances its service life.

[101] The embodiments described herein are intended to demonstrate various aspects of the invention, and those skilled in the art should understand that modifications and variations may be made without deviating from the core principles of the invention. The scope of the invention is not limited to the specific embodiments shown; alternative constructions, configurations, and methods may be implemented within the spirit of this disclosure.

[102] Thus, it will be appreciated by those of ordinary skill in the art that the diagrams, schematics, illustrations, and similar representations serve as conceptual views or processes illustrating the systems and methods embodying this disclosure. The functions of the various elements depicted in the figures may be realized through careful observation of potential structures, with specific techniques being selectable by the entity implementing this disclosure.

[103] While embodiments of the present disclosure have been illustrated and described, it will be clear that the disclosure is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the disclosure, as described in the claims.

[104] ADVANTAGES OF THE PRESENT INVENTION

Reduced Deflection: The deflection of the bridge abutment caused by lateral forces from vehicular loads is substantially decreased, enhancing the structural integrity and longevity of the bridge abutment.
Flood Resilience: In bridges spanning water bodies, abutments can be spaced approximately 5 to 6 meters apart, with the pavement designed as a reinforced cement concrete slab supported by these multiple abutments. This arrangement ensures that even if part of the approach embankment backfill is washed out during floods, access to the bridge remains secure.
Lower Maintenance Frequency: The use of multiple abutments helps ensure that the approach embankments do not require frequent replacement, resulting in reduced maintenance efforts and costs over time.
Replacement of Old Structures: Multiple abutments can be constructed to replace old approach embankments that need backfill replacement, providing a more durable and effective solution for infrastructure upgrades.
Independent Construction: These abutments can be built independently on either side of a box culvert, offering flexibility in design and construction while enhancing overall structural support.
, Claims:WE CLAIM:
1. A multiple abutment structures for reduced deflection comprising: at least one vertical structure built within an approach embankment (4) of the bridge (1); wherein the said vertical structures are a plurality of abutments (9) constructed in series between the base foundation and the pavement of the approach embankment;
characterised in that
a. lateral vehicular load (6) is distributed across the said abutments (9), and
b. the said abutments (9) are of sequentially increasing heights towards the bridge (1).
2. The abutment structures as claimed in claim 1, wherein the spacing between the said abutments (9) that are adjacent depends on the vehicular load (6).
3. The abutment structures as claimed in claim 1, wherein the spacing between the said abutments (9) depends on location and function of the bridge.
4. The abutment structures as claimed in claim 1, wherein the spacing between the said abutments (9) is flexible and is not limited to equidistant arrangements.
5. The abutment structures as claimed in claim 1, wherein the said abutments (8) closer to the bridge are intended as integration with approach slab (3) supporting the pavement.
6. The abutment structures as claimed in claim 4, wherein each of the said abutment (9) is constructed from reinforced cement concrete and the like.
7. The abutment structures as claimed in claim 1, wherein the said structure allows access to the bridge (1) even if portions of the approach embankment (4) are battered.
8. The abutment structures (9) as claimed in claim1, wherein allows the independent placement of abutments (9) alongside other structural elements but not only limited to box culverts.
9. The abutment structures (9) as claimed in claim1, wherein the percentage improvement in reduced deflection ranges from 80% to 93%.

10. A method for reducing the deflection in abutment structures (1) comprising:
evaluating measurements and analysing vehicular load,
erecting vertical structures that are a plurality of abutments (9) in series between the base foundation and the pavement of the approach embankment which distributes the lateral vehicular load across the said abutments(9), and designing the said abutments of sequentially increasing heights towards the bridge within in approach embankment.
11. The method as claimed in claim 1, wherein the spacing between the said abutments (9) is flexible and is not limited to equidistant arrangements.
12. The method as claimed in claim 1, wherein the spacing between the said abutments (9) depends on location and function of the bridge (1).

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