Trip Curve Calculator

Enter Hauling Inputs

Units

Speeds follow the same distance unit per hour.

One-way haul distance (km) *

Loaded speed (km/h) *

Empty speed (km/h) *

Route grade (%)

Used to reduce speeds with a simple factor.

Speed loss per 1% grade (%)

Load time (min)

Dump time (min)

Spot/turn time (min)

Queue / delay (min)

Payload per truck (units, loose)

Use m³, tons, or yd³ consistently.

Swell (%)

Bank = loose ÷ (1 + swell).

Availability (%)

Efficiency (%)

Hours per day

Number of trucks

Target daily output (units)

Cost per truck-hour

Curve Table Settings

Curve start distance (km)

Curve end distance (km)

Step (km)

Reset

Example Data Table

Parameter	Example value	Notes
One-way distance	1.8 km	Haul road centerline distance
Loaded / Empty speed	28 / 35 km/h	Use realistic site speeds
Load / Dump	2.5 / 1.5 min	Include operator variability
Spot + Queue	0.8 + 1.2 min	Traffic and maneuvering time
Payload (loose)	12 units	m³, yd³, or tons—stay consistent
Swell	20%	Converts loose to bank volume
Availability / Efficiency	85% / 80%	Applies to trips per hour

Formula Used

Travel time (minutes): t = (distance / speed) × 60

Cycle time (minutes): CT = t_loaded + t_empty + load + dump + spot + queue

Trips per hour: TPH = 60 / CT

Effective trips per hour: ETPH = TPH × (availability/100) × (efficiency/100)

Production per hour (loose): Q_loose = payload × ETPH

Production per hour (bank): Q_bank = Q_loose ÷ (1 + swell)

Unit cost: Cost_unit = (fleet_cost_per_hour) ÷ (fleet_production_per_hour)

Speed adjustment: speed_adj = speed × (1 − |grade| × loss_per_grade), limited to a minimum factor.

How to Use This Calculator

Choose your distance unit and enter the one-way haul distance.
Enter loaded and empty speeds based on actual site conditions.
Add loading, dumping, spot, and queue times to capture delays.
Enter payload and swell to convert between loose and bank outputs.
Set availability and efficiency to reflect real operating time.
Specify trucks, hours per day, and cost per truck-hour for economics.
Adjust curve settings to generate a distance-versus-output table.
Download CSV or PDF after calculating for reporting.

Trip Curve Guide for Hauling Planning

1) Why trip curves matter on site

A trip curve links haul distance to cycle time, trips per hour, and output. Small changes in distance or delays can shift daily production by many units. Use curves to compare routes, set expectations, and defend fleet choices with confidence.

2) Inputs that shape cycle time

Cycle time combines loaded travel, empty travel, and fixed delays. Typical speeds might be 20–35 km/h loaded and 25–45 km/h empty. Loading, dumping, spotting, and queue time commonly totals 4–7 minutes per cycle.

3) Converting distance to travel minutes

Travel time uses t = (distance ÷ speed) × 60. For a 2.0 km one‑way haul at 28 km/h loaded, loaded travel is about 4.29 minutes. If the return is 35 km/h, empty travel is about 3.43 minutes, forming the distance‑driven curve portion.

4) Managing delays and variability

Fixed delays often dominate short hauls. A one‑minute increase in queue time affects every cycle and can cut trips per hour by 5–10%. Update load and dump times from observations, and keep spot time as a buffer for turning, backing, and traffic control.

5) Availability and efficiency factors

Raw trips per hour assume perfect operation, so apply availability and efficiency. Availability covers breakdowns, fueling, and shift losses, often 80–90%. Efficiency reflects coordination and operator rhythm, commonly 70–85%. Multiplying both produces effective trips per hour.

6) Payload, swell, and bank conversion

Production per hour equals payload times effective trips per hour. If payload is 12 loose units and effective trips per hour is 3.0, output is 36 loose units per hour. With 20% swell, bank output becomes 36 ÷ 1.20 = 30 bank units per hour.

7) Fleet sizing and unit cost

Fleet output multiplies per‑truck output by truck count. If one truck produces 30 bank units per hour and you run four trucks, the fleet produces 120 bank units per hour. With a cost of 55 per truck‑hour, hourly fleet cost is 220; unit cost is 220 ÷ 120 ≈ 1.83.

8) Reading the curve table for decisions

As distance increases, cycle time rises and trips per hour falls, so unit cost climbs. Use the table to spot breakpoints where adding a truck is cheaper than extending shifts. Export CSV for estimating sheets, and keep a PDF snapshot for coordination.

FAQs

1) What is a trip curve used for?

It shows how haul distance affects cycle time, trips per hour, and output, helping you plan trucks, shifts, and costs for earthwork or material hauling.

2) Should I enter one-way or round-trip distance?

Enter the one-way haul distance. The calculator automatically adds the loaded and empty travel legs to form a full cycle.

3) How do availability and efficiency differ?

Availability covers downtime like fueling, breaks, and repairs. Efficiency reflects operating rhythm and coordination while running. Both reduce ideal trips per hour to realistic performance.

4) How do I choose payload units?

Use one consistent payload unit, such as m³, yd³, or tons. Production and unit cost will follow the same unit, so avoid mixing units across inputs.

5) What does swell change in results?

Swell converts loose volume to bank volume using bank = loose ÷ (1 + swell). It helps align hauling output with cut and fill quantities.

6) Why does unit cost rise with distance?

Longer hauls increase travel time, which reduces trips per hour. With hourly costs similar, fewer units moved per hour increases cost per unit.

7) How many rows can the curve table show?

The table caps at 60 rows for fast loading. Adjust start, end, and step sizes to focus on the distance range you need.