The initial procedure is the identification of the sub-elements belonging to each element, and through visual inspection, the associated damage pathologies are detected, as shown in Table 6. Then, the total dimension measurements of the sub-elements and the deterioration of the measurement in the same sub-elements. This way, it is possible to quantify the damage density for each pathology identified with Eq. 1.

With the calculated damage pathology density, it is possible to define the density coefficient (D.C.) based on severity ranges that allow the affectations to be classified as low, medium, or high (1, 2, and 3, respectively) for the Sub Elements, the values mentioned are proposed in Table 6. The selection criteria of the severity ranges for the definition of the D.C. obeys the importance and degree of vulnerability generated in the entire structure in case of failure of the Sub Element.

Then, the importance coefficients (I.C.) are proposed, as shown in Table 1, with a variation on a scale from 1 to 5. These coefficients depend on the priority of each element for the optimal general behavior of the structure and the influence it has on adjacent structures. An example of the above is the effects on drainage; according to the visual inspection manual of bridges and pontoons of Invías, three types of pathology can be identified (plugged, absence, and insufficient drainage length), and each one of them has an I.C. different. Consequently, the most important is the absence of drains with a value of 5, because, in case of blockage or insufficient length, the adverse effects can be corrected with maintenance activities, but in the case of absence, there is a high probability of presenting filtration problems to other elements of the structure, such as the slab, beams, and supports. Therefore, it is highly probable that other types of more severe pathologies will be triggered.

Table 1

Element	Sub Element	I.C.
Expansion joints	Sealant	4
	Profile	2
	Corner guard	2
Platforms / kerbstone	Corner chipping	2
	Exposed steel	3
	Insufficient dimensions	3
Railings	Paint	1
	Poles	2
	Railing	3
Signaling	Horizontal	2
	Vertical	3
	Reducers	1
Drainage	Plugged	2
	Absence	5
	Insufficient length	3
Concrete structures	Design	3
	Construction	4
	Operation	2
Steel arches	Arch left and right	4
	Lateral bracing	2
Steel profiles	Beams	4
	Stringer	3
	Diaphragms	2
Steel trusses	Steel cords	3
	Steel uprights	4
	Steel diagonals	2
Steel connections	Welding	4
	Steel connectors	2
	Steel pins	1
Cables/ Struts/Towers	Cables	3
	Struts	4
	Towers	2

Source: Authors, 2022.

Obtained the Density Coefficients for each evidenced pathology and the Importance Coefficients for each sub-element, the weighted average (W.A.P.) of each registered pathology is calculated as shown in Eq. 2. Then, the Degree of Affectation of each Element (D.A.E. %) is calculated as shown in Eq. 3, where the sum of all the weighted averages of pathologies of each element must be considered and related to the coefficients D.C., and the coefficients I.C. of each pathology.

Consequently, the Degree of Affectation for each Subcategory (DASC%) is determined as shown in Eq. 4, where an Element Coefficient (E.C.) is assigned to each element. The influence criterion is considered in the general structure, a similar case for obtaining the I.C. The proposed values are presented in Table 2. Additionally, the Degree of Affectation of each Element (DAE%) is considered.

Table 2

Subcategory	E.C.
Expansion joints	3
Platforms / kerbstone	1
Railings	2
Signaling	2
Drainage	4
Bridge fins	4
Bridge abutments	4
Pillars	2
Slab	3
Beams	5
Strut	3
Bridge supports	5
Concrete arches	5
Steel arches	5
Steel profiles	4
Steel Trusses	4
Steel connections	5
Cables/ Struts/Towers	3

Source: Authors, 2022.

Subsequently, the Degree of Total Affectation of the bridge (DTA%) is calculated as evidenced in Equation 5, based on the weighted average methodology, for which the Categorical Element Coefficient (C.E.C.) is proposed, with similar criteria to those previously described for other coefficients as presented in Table 3.

Table 3

	C.E.C.
Surface and equipment	2
Substructure	5
Concrete superstructure	5
Steel superstructure	5

Source: Authors, 2022.

Finally, according to the Degree of Total Affectation of the bridge (DTA%) obtained by applying the WABIM methodology, comments related to the condition of the structure and maintenance recommendations are presented, increasing the objectivity of the analysis represented in the level of risk for the users. Therefore, the percentage ranges of total affectation, analysis, and recommendations are presented in Table 4.

Table 4

Ranges		Bridge condition	Recommendation
0%	10%	No deterioration	Schedule long-term maintenance
10.1%	40%	Low deterioration	Schedule maintenance
40.1%	50%	Moderate deterioration	Schedule short-term maintenance
50.1%	90%	Medium-high deterioration	Schedule immediate maintenance
90.1%	100%	High deterioration Susceptible to collapse	Maximum risk state - Close the use of the structure

Source: Authors, 2022.

When there is a value of DTA% between 0% and 10%, it is considered without deterioration. Therefore, long-term preventive maintenance programming is recommended. On the contrary, when the total deterioration values are between 10.1% and 40%, it is considered a low level of deterioration; a preventive maintenance intervention is necessary for the medium term, and some corrective maintenance activities may be necessary for the bridge. When a DTA% value between 40.1% and 50% is evidenced, it is considered moderate damage to the bridge. Consequently, it shows the short-term need for corrective and preventive maintenance.

Accordingly, when bridge deterioration values between 50.1% and 80% are present, the analysis must consider an immediate intervention of the structure through mainly corrective maintenance; it is considered a medium-high deterioration. Finally, when a DTA% value between 80.1% and 100% is presented, it is necessary to declare the structure in a maximum risk state due to its high deterioration with susceptibility to bridge collapse. Therefore, the immediate recommendation is the closure of the service.

Esneda bridge has two reinforced concrete abutments in good structural condition; however, there is biological contamination of the concrete generated by excessive vegetation, and there is no evidence of deterioration of the abutments due to the action of the river flow. The bridge's pavement is rigid (hydraulic concrete) without showing any visual pathology of deterioration; also, the expansion joints are in good condition. The bridge does not have signs or lighting, the structure does not have a pedestrian zone, and the passage is restricted to heavy vehicles.

The structural configuration of the bridge consists of warren-type steel trusses. The lower chord is made of W-type beams; the uprights and diagonals of each truss and the lateral bracing are made of simple and double-angle-type steel profiles. Additionally, the upper chord of the bridge is made of elements joined by steel rivets that form a box-type section. All connections are made with plates using steel rivets. Moreover, the bridge deck is a hydraulic concrete slab supported by a framework of W-type steel beams.

Table 6

Sub Category / Element		Sub Element	Low	Medium	High
Surface and equipment	Expansion joints	Sealant	Less than 5%	5%-25%	Greater than 25%
		Profile	Less than 20%	20%-50%	Greater than 50%
			Less than 3%	3%-7%	Greater than 7%
		Corner guard	Less than 15%	15%-30%	Greater than 30%
	Platforms / kerbstone	Corner chipping	Less than 15%	15%-30%	Greater than 30%
		Exposed steel	Less than 15%	15%-30%	Greater than 30%
		Insufficient dimensions	Less than 30%	30%-60%	Greater than 60%
	Railings	Paint	Less than 30%	30%-60%	Greater than 60%
		Poles	Less than 30%	30%-60%	Greater than 60%
		Railing	Less than 20%	20%-40%	Greater than 40%
	Signaling	Horizontal	Less than 20%	20%-40%	Greater than 40%
		Vertical	Less than 20%	20%-40%	Greater than 40%
		Reducers	Less than 20%	20%-40%	Greater than 40%
	Drainage	Plugged	Less than 15%	15%-30%	Greater than 30%
		Absence	Less than 15%	15%-30%	Greater than 30%
		Insufficient length	Less than 15%	15%-30%	Greater than 30%
Concrete substructure and superstructure	Design	AL, AL, VO	Less than 15%	15%-30%	Greater than 30%
		FIF, F.I.C., F.I.T.	Less than 10%	10%-30%	Greater than 30%
	Construction	S.E., H.O., F.I.R., J.F., RE, E.X.A.	Less than 5%	5%-25%	Greater than 25%
	Operation	IN, E.F., C.A.R., C.O.A., C.T.C., I.M.P., S.O.C.	Less than 20%	20%-50%	Greater than 50%
Steel superstructure	Steel arches, Steel profiles, Steel trusses	COL-COM-COS-PI-PGL-DX	Less than 15%	15%-30%	Greater than 30%
		FIV	Less than 10%	10%-30%	Greater than 30%
		I.M.P.	Less than 20%	20%-40%	Greater than 40%
	Steel connections	A.U.C., EX, T.P., A.P., DG, CT, B.Q., S.O.L.	Less than 20%	20%-40%	Greater than 40%
	Cables/ Struts/Towers	P.R.C., T.E.C., F.I.A., F.I.M., C.T.A.	Less than 10%	10%-30%	Greater than 30%
		P.L., PGL, FIV, DX	Less than 20%	20%-40%	Greater than 40%

Source: Authors, 2022.

Some of the deterioration detected in terms of the steel structure elements is the deterioration of paint. It becomes a slight corrosion phenomenon in specific areas of the upper chord. On the other hand, in the elements of the concrete substructure, there is evidence of biological contamination of the concrete and efflorescence in a large part of the abutments.

Starting from the qualitative methodology contained in the Manual of visual inspection of bridges and pontoons of Invías, the WABIM methodology was applied to the La Esneda bridge structure, allowing the generation of objective analysis and recommendations based on the deterioration measurement results of all the elements of the bridge presented in Fig. 4.

Figure 4 Source: Authors, 2022.

The category with the highest degree of affectation was that of surface and equipment with 31.55%; many specific areas of the railings show slight corrosion and paint detachment. Additionally, the bridge does not have signage or lighting. These deteriorations occur due to exposure to environmental conditions and lack of structural maintenance.

The substructure has 21.21% efflorescence due to the vegetation that the concrete abutments present, as shown in Fig. 5, which can cause significant damage in the future at the integral level of the structural reinforcing steel and the physicochemical composition of the concrete. Nevertheless, the integrity of the abutments has not been severely affected.

Figure 5 Source: Authors, 2022.

Efflorescence does not constitute a problem of durability of the structures; though, it affects the aesthetics and causes an increase in the porosity of the concrete and an increase in permeability, increasing the vulnerability of the concrete to other pathologies deteriorate the structure.

The concrete superstructure has a 4.98% impact on the slab due to some contaminated areas efflorescence on the sides. This agent is due to the high humidity in the area and lack of maintenance on the bridge. The steel superstructure has 18.57% damage, and the lower chords and the diagonals have slight corrosion, as shown in Fig. 6.

Figure 6 Source: Authors, 2022.

According to the results of DTA% shown in Table 7, the bridge presents low deterioration, for which it is recommended to schedule maintenance with activities focused on the installation of signage, lighting, and painting to avoid the progression of more serious pathologies, severe in steel elements. Cleaning and waterproofing of the concrete substructure are also necessary to prevent future damage to the steel-reinforced concrete elements.

Table 7

DTA% Results
DTA%:	16.88%
Bridge Condition:	Schedule maintenance Schedule short-term maintenance Low deterioration
Maintenance emphasis:	Signage and painting

Source: Authors, 2022.